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See detailBrain Trains: Intermodal Rail Freight Transport and Hinterland Connections - A Swot Analysis to Assess the Belgian Rail Practice
Troch, Frank; Vanelslander, Thierry; Sys, Christa et al

in Proceedings of the IAME Annual Conference 2015 (2015, August)

This paper focuses on transversal research of the role and influences of rail freight transport, as a part of intermodal transport in Belgium. The scope of the research concentrates on port hinterland ... [more ▼]

This paper focuses on transversal research of the role and influences of rail freight transport, as a part of intermodal transport in Belgium. The scope of the research concentrates on port hinterland flows. A large SWOT analysis of the current situation is conducted, starting from the actual weak usage of this mode of transport. Five different fields have been identified, impacting the economy and society. Each field indicates critical internal strengths and weaknesses for intermodal rail transportation in Belgium, and identifies possible future developments and setbacks. A Delphi-like approach is used, including a heterogeneous panel of experts discussing and validating the SWOT results. To prioritize the characteristics, a survey on the different SWOT elements was performed, asking the experts to rate each statement on its influence and likelihood of happening (level of uncertainty). [less ▲]

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See detailGenetic variability of MIR predicted milk technological properties in Walloon dairy cattle
Colinet, Frédéric ULg; Troch, Thibault ULg; Baeten, Vincent et al

in Book of Abstracts of the 66th Annual Meeting of the European Federation of Animal Science (2015, August)

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See detailStroke Volume Estimation using Aortic Pressure Measurements and Aortic Cross Sectional Area: Proof of Concept
Kamoi, Shun; Pretty, Christopher G.; Chiew, Yeong Shiong et al

in Proceedings of the 37th International Conference of the IEEE Engineering in Medicine and Biology Society (2015, August)

Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of ... [more ▼]

Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of measurement devices. Current devices for indirect monitoring of SV are shown to be inaccurate during sudden hemodynamic changes. This paper presents a novel SV estimation using readily available aortic pressure measurements and aortic cross sectional area, using data from a porcine experiment where medical interventions such as fluid replacement, dobutamine infusions, and recruitment maneuvers induced SV changes in a pig with circulatory shock. Measurement of left ventricular volume, proximal aortic pressure, and descending aortic pressure waveforms were made simultaneously during the experiment. From measured data, proximal aortic pressure was separated into reservoir and excess pressures. Beat-to-beat aortic characteristic impedance values were calculated using both aortic pressure measurements and an estimate of the aortic cross sectional area. SV was estimated using the calculated aortic characteristic impedance and excess component of the proximal aorta. The median difference between directly measured SV and estimated SV was -1.4ml with 95% limit of agreement +/- 6.6ml. This method demonstrates that SV can be accurately captured beat-to-beat during sudden changes in hemodynamic state. This novel SV estimation could enable improved cardiac and circulatory treatment in the critical care environment by titrating treatment to the effect on SV. [less ▲]

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See detailComparison between thermographic and holographic techniques for nondestructive testing of composites: similarities, differences and potential cross-fertilization
Georges, Marc ULg

in Mendoza Santoyo, Fernando (Ed.) SPECKLE 2015: VI International Conference on Speckle Metrology (2015, August)

Thermography and different variants of holography (holographic interferometry, speckle interferometry, shearography) are full-field non-contact techniques which are used in nondestructive testing ... [more ▼]

Thermography and different variants of holography (holographic interferometry, speckle interferometry, shearography) are full-field non-contact techniques which are used in nondestructive testing applications. In particular they are attractive for damage detection in composite materials compared to other methods measuring in one point and which require scanning and contact with the samples, like ultrasounds. Currently thermography is a step forward compared to holographic techniques for this application. Indeed it is easier to interpret. Many thermography configurations and variants exist, from exciting sources to post-processing. Such a variety exists also among the holographic techniques but to a less extent. We will see how these techniques can share some aspects and what distinguish them. Also the complementarity of both will be addressed and how to combine them. At last we will discuss how processing developed for thermography can benefit to holography and vice-versa, specifically in the domain of composite materials. [less ▲]

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See detailGenetic heritage of the Eastern Belgium Red and White breed, an endangered local breed
Colinet, Frédéric ULg; Bouffioux, Aude; Mayeres, Patrick et al

in Book of Abstracts of the 66th Annual Meeting of the European Federation of Animal Science (2015, August)

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See detailIs the Mehler reaction the main photoprotective mechanism occurring in Symbiodinium in hospite?
Roberty, Stéphane ULg; Beraud, Eric; Ferrier-Pagès, Christine et al

Poster (2015, August)

The ecological success of reef-building corals throughout tropical oligotrophic waters relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium. This ... [more ▼]

The ecological success of reef-building corals throughout tropical oligotrophic waters relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium. This association allows the transfer of highly energetic compounds and an efficient recycling of growth-limiting nutrients. In the natural environment the holobiont have to cope with significant daily variations in light intensities that sometimes exceed Symbiodinium photosynthetic capacity. Fortunately, these organisms possess regulatory features that help to ensure that high light intensities can be endured without the accumulation of photodamage. Among them, it has been found recently that photoreduction of oxygen downstream PSI by the so-called Mehler reaction was the main alternative electron sink at the onset and steady state of photosynthesis in different cultured strains of Symbiodinium. In this study, we investigated the occurrence and the relative amplitude of this photoprotective mechanism in Symbiodinium cells living within the tropical coral Stylophora pistillata and the sea anemone Anemonia viridis. To this end, joint measurements of oxygen evolution, PSI and PSII activities were conducted. The impacts of CO2 limitation and CO2 fixation on the photoreduction of oxygen by PSI was also studied by using several inhibitors targeting the carbon concentrating mechanism and the Calvin-Benson-Bassham cycle. Conversely to cultured cells, these measurements revealed that the Symbiodinium located in S. pistillata, under control conditions, rely on other photoprotective mechanisms than the Mehler reaction to prevent over-excitation of the photosynthetic apparatus. However, we observed an increased O2 uptake capacity during photosynthesis when the efficiency of the carbon fixation was reduced in S. pistillata. [less ▲]

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See detailIsolation and identification of anthropogenic particles in fish stomachs by Raman spectroscopy: a new method
Collard, France ULg; Gilbert, Bernard ULg; Eppe, Gauthier ULg et al

in Organohalogen Compounds (2015, August)

Microplastic particles (MP) contaminate oceans and affect marine organisms in several ways. Ingestion combined with food intake is generally reported. However, data interpretation is often circumvented by ... [more ▼]

Microplastic particles (MP) contaminate oceans and affect marine organisms in several ways. Ingestion combined with food intake is generally reported. However, data interpretation is often circumvented by the difficulty to separate MP from bulk samples. Visual examination is often used as one or the only step to sort these particles. However, color, size and shape are insufficient and often unreliable criteria. Here we present an isolation method of MP specially adapted to a subsequent analysis by Raman spectroscopy. This method avoids fluorescence problems allowing the identification anthropogenic particles (AP) from stomach contents of fish by Raman spectroscopy. It was validated with commercial samples of microplastics and cotton along with stomach contents from three different Clupeiformes fishes: Clupea harengus, Sardina pilchardus and Engraulis encrasicolus. The optimized digestion and isolation protocol showed no visible impact on microplastics and cotton particles while the spectroscopic analysis allowed precise identification of microplastics and textile fibers. This approach allowed us to isolate 35 particles. These were analyzed by Raman spectroscopy: eleven were microplastics and thirteen were made of cellulose or lignin, or both (mostly fibers). Some particles were not identified but contained artificial colorants. This isolation protocol will help to assess the presence, quantity and composition of AP in planktivorous fish stomachs. [less ▲]

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See detailGenetic heritage of the Eastern Belgium Red and White breed, an endangered local breed
Colinet, Frédéric ULg; Bouffioux, Aude; Mayeres, Patrick et al

Poster (2015, August)

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See detailModelling of the Nonlinear End-Systolic Pressure-Volume Relation and Volume-at-Zero-Pressure in Porcine Experiments
Davidson, Shaun M.; Kannangara, D. Oliver; Pretty, Christopher G. et al

Poster (2015, August)

The End-Systolic Pressure-Volume Relation (ESPVR) is generally modelled as a linear relationship between P and V as cardiac reflexes, such as the baroreflex, are typically suppressed in experiments ... [more ▼]

The End-Systolic Pressure-Volume Relation (ESPVR) is generally modelled as a linear relationship between P and V as cardiac reflexes, such as the baroreflex, are typically suppressed in experiments. However, ESPVR has been observed to behave in a curvilinear fashion when cardiac reflexes are not supressed, suggesting the curvilinear function may be more clinically appropriate. Data was gathered from 41 vena cava occlusion manoeuvres performed experimentally at a variety of PEEPs across 6 porcine specimens, and ESPVR determined for each pig. An exponential model of ESPVR was found to provide a higher correlation coefficient than a linear model in 6 out of 7 cases, and a lower Akaike Information Criterion (AIC) value in all cases. Further, the exponential ESPVR provided positive V0 values in a physiological range in6 out of 7 cases analysed, while the linear ESPVR produced positive V0 values in only 3 out of 7 cases, suggesting linear extrapolation of ESPVR to determine V0 may be flawed. [less ▲]

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See detailGenetic analysis to support the re-establishment of the Kempen breed
François, Liesbeth; Janssens, Steven; Colinet, Frédéric ULg et al

in Book of Abstracts of the 66th Annual Meeting of the European Federation of Animal Science (2015, August)

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See detailNiche-innovations between breaks and continuities with the regime? A case study into the dairy sector in Belgium
Feyereisen, Marlène ULg; Melard, François ULg; Stassart, Pierre M ULg

Conference (2015, August)

Today, the absolute dichotomy between alternative food networks (AFNs) and the conventional agrofood system tends to be obsolete. Indeed, many AFNs are far from being radical and are more likely to ... [more ▼]

Today, the absolute dichotomy between alternative food networks (AFNs) and the conventional agrofood system tends to be obsolete. Indeed, many AFNs are far from being radical and are more likely to maintain relations with the current socio-technical regime between breaks and continuities. This contribution is a complement to the Transition Theory and the Multi-Level Perspective by underlying the fragile borders between the two levels of the niche-innovations and the socio-technical regime: some imperfect projects, full of contradictions, are participating to the transition of the system. And this is particularly true in the case of highly locked in systems. The dairy sector in Western European countries is one of those highly locked in systems. Our case study, the Belgian fair-trade milk “Fairebel”, is a project built by dairy farmers to react to the 2009 dairy crisis and to the increasingly neoliberal dairy sector; and to get a better price (or fair price) for their activity. However, the concretization of this project brought its share of contradictions regarding the common definition of fair trade milk. As a result, the “Fairebel” project maintains relations between breaks and continuities with the regime. This contribution suggests modes of governance for the stakeholders of these non-radical niches which are precious to engage change in highly locked in system without being picked up by the dominant regime and thus, keep this regime under pressure. [less ▲]

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See detailSinging accuracy, listeners’ tolerance, and pitch analysis
Larrouy, Pauline ULg; Devaney, Johanna

Conference (2015, August)

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See detailLes carrières des cadres : regard croisé du sexe (genre) et de l'âge (générations).
Grodent, Françoise ULg; Cornet, Annie ULg

Conference (2015, August)

Ce papier a pour objectif la construction d'une grille d'analyse destinée à comparer les trajectoires professionnelles des hommes et des femmes cadres issus de trois groupes d'âge différents, à savoir les ... [more ▼]

Ce papier a pour objectif la construction d'une grille d'analyse destinée à comparer les trajectoires professionnelles des hommes et des femmes cadres issus de trois groupes d'âge différents, à savoir les moins de 35 ans, les [35-50] ans et les plus de 50 ans. Le fait d’introduire la dimension de l'âge, en plus de celle du sexe, s’appuie sur la notion d’intersectionnalité qui vise à analyser la manière dont se combinent différentes caractéristiques de la diversité (ici le genre et l’âge) dans les trajectoires professionnelles des cadres. L’âge a été découpé en trois groupes de manière arbitraire, cela dans l’idée d’avoir trois catégories d’âge qui cohabitent actuellement et à la même période dans l’entreprise. Ces trois dernières peuvent recouper certaines générations, porteuses de diverses valeurs et représentations qui renvoient notamment aux rôles attribués aux hommes et aux femmes ainsi qu'à certaines attentes quant aux comportements de l’un et l’autre sexe. Cette comparaison intergénérationnelle nous permettra de mobiliser les théories du genre, à savoir les constructions socio-culturelles du féminin et du masculin, les rôles attribués aux femmes et aux hommes ainsi que les rapports sociaux entre les sexes, enracinés dans leur contexte historique. L’objectif est de proposer une grille de lecture qui sera utilisée pour l’analyse de données tant quantitatives que qualitatives collectées dans le cadre d'une thèse en cours de finalisation. Ce travail s’appuie sur une approche abductive, à savoir sur la volonté de faire des allers et retours entre des grilles d’analyse théoriques et des données inductives, utilisées à leur tour pour questionner et affiner les grilles d’analyse proposées. [less ▲]

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See detailApplication of next generation sequencing for study and diagnosis of plant viral diseases in agriculture
van der Vlugt, René; Minafra, Angelanotio; Olmos, Antonio et al

Poster (2015, August)

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See detailOn the use of novel milk phenotypes as predictors of difficult-to-record traits in breeding programs
Bastin, Catherine ULg; Colinet, Frédéric ULg; Dehareng, Frédéric et al

in Book of Abstracts of the 66th Annual Meeting of the European Federation of Animal Science (2015, August)

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See detailMid-winter surveys for sea ice biogeochemistry in bi-polar oceans
Nomura, D.; Delille, Bruno ULg; Dieckmann, G. et al

Conference (2015, August)

Sea ice has rarely been considered in estimates of global biogeochemical cycles, especially gas exchanges, because of the assumption that, in ice-covered seas, sea-ice acts as a barrier for ... [more ▼]

Sea ice has rarely been considered in estimates of global biogeochemical cycles, especially gas exchanges, because of the assumption that, in ice-covered seas, sea-ice acts as a barrier for atmosphere–ocean exchange. However, recent work has shown that sea ice and its snow cover play an active role in the exchange of gases between the ocean and atmosphere [1] [2]. Our results provide a useful reference for future studies as the ongoing drastic changes in polar climate and sea ice extent are likely to alter the biogeochemical cycles in polar ocean–sea ice–atmosphere system. However,, the lack of information for the winter-time sea ice biogeochemistry was pointed out, due to the difficulty to acquire data under harsh weather conditions. In this presentation, we will present our recent winter-time sea ice surveys of sea ice biogeochemistry on the R/V Aurora Australis off East Antarctica (SIPEX-II) in 2012 and the midwinter sea ice cruise on the R/V Polarstern in the Weddell Sea, Antarctica (AWECS) in 2013. In addition, we will also show the ongoing project of Norwegian Young sea ICE cruise (NICE2015) on the R/V Lance drifting for half a year in Arctic sea ice north of Svalbard in 2015. [1] Nomura et al. (2013) J. Geophys. Res. Oceans 118, 6511- 6524. [2] Delille et al. (2014) J. Geophys. Res. Oceans 119, 6340-6355. [less ▲]

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See detailDynamique de l'espace architectural : force, vitesse, déplacement dans l'oeuvre de Le Corbusier
Steinmetz, Rudy ULg

in Revue Philosophique de Louvain (2015, August), Tome 113(3), 425-447

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See detailThe effects of triclosan exposure in shape changes of sheepshead minnow (Cyprinodon variegatus) during early development and metamorphosis
Schnitzler, Joseph ULg; Frederich, Bruno ULg; Dussenne, Mélanie ULg et al

in Organohalogen Compounds (2015, August)

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation ... [more ▼]

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation, metabolism, somatic growth and post-hatching metamorphosis [1, 3, 4]. The regulation of thyroid hormone bioavailability in tissues and cells represents a very complex and unique web of feedback systems [2]. In fish and other vertebrates the thyroid cascade involves two components. First, thyroxine (T4) biosynthesis and secretion are largely under central control by the brain–pituitary–thyroid axis [5]. Second, there is the conversion of T4 to its biologically active form 3,5,3-triiodothyronine (T3) and its metabolism and receptor-mediated actions that seems largely to be under peripheral control in extra-thyroidal tissues [6]. The accumulation in the aquatic environment of anthropogenic chemicals, among which are endocrine disrupting chemicals (EDCs) that alter normal hormonal regulation, is having dramatic consequences for humans and wildlife. Numerous chemicals disrupt thyroid homeostasis affecting thyroid hormone (TH) synthesis and transport, and cellular uptake and metabolism [7, 8]. Triclosan (TCS) is a synthetic chlorinated phenolic compound with a generalized use as an antimicrobial and preservative in many personal care and household products [9-11]. As a result of disposal of TCS through sewage systems and insufficient/variable removal by wastewater treatment plants (WWTP) [9], widespread contamination with TCS has been detected in several countries, particularly in aquatic ecosystems, WWTP influents and effluents; sludges and biosolids; surface or ground water; drinking water; and aquatic sediments [9-11]. TCS and its metabolites have been detected in tissues and body fluids of aquatic organisms including fish, revealing they are accumulating in the food chain [9-11] and TCS has also been detected in human blood, breast milk and urine [9-11]. The structural similarity of TCS with THs [9] suggest it may have adverse effects on the thyroid system. However, little is known about the mechanisms by which TCS disrupts the thyroid axis. TCS effects on fish thyroid axis have not been investigated. It is possible, that the TCS toxic effects reported in fish embryos, larvae and adults [9-11] might be caused, at least in part, through its effect on the thyroid system. We determined how TCS affect ontogenic variations of thyroid hormones in developing sheepshead minnow larvae. Knowing that thyroid hormones are involved in somatic growth and post-hatching metamorphosis, we also tested the hypothesis that TCS alter the development of these larvae. To do this, we used landmark-based geometric morphometric methods. These methods allowed us to analyse the pure shape variations of our developing larvae, regardless orientation, position, and size. [less ▲]

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See detailPhysical modeling of lateral dike breaching due to overtopping
Rifai, Ismail; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in River, Coastal and Estuarine Morphodynamics, RCEM 2015 (2015, August)

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures ... [more ▼]

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures, combined with their increased vulnerability to extreme hydrological events may cause the dikes to breach, and subsequently to break. Furthermore, statistics show that flow overtopping is the main cause of dike failure, which emphasizes the need to understand thoroughly the process of breaching. Indeed, from a risk management perspective it is particularly important to have a detailed understanding of the mechanisms (e.g. internal erosion, overtopping erosion) underlying the formation of breaches due to overtopping and reliable information on flows passing through them. Conversely, the current knowledge of breaching mechanisms remains fragmented, especially because dike failure involves complex interactions between flows, materials of the structure, soil and foundations. The existing studies have addressed partially these interactions as the considered idealized dikes were generally homogenous, the piping erosion unaccounted for and the overtopping replicated in a dam-break like configuration. Yet, river embankments are subjected to high flow velocities parallel to the direction of the dike and to flow in the floodplain, which highly influence the shape of the breach and its evolution. The objective of the present work is to fill this gap. A laboratory experimental investigation is planned in the National Laboratory for Hydraulics and Environment (LNHE) of EDF R&D (France) and in the research group Hydraulics in Environmental and Civil Engineering (HECE) of the University of Liege (Belgium), reproducing realistic configurations of river dikes, accounting for the tangential flow in both main channel and floodplain. It enables thus the assessment of, on the one hand, the effect of the increase of the water level, and on the other hand, the influence of waves. The laboratory tests also consider the effect of a surface layer and composition of the dike core by testing different material mixtures. Geometry and composition of the idealized dikes are representative of typical field dikes, based on the similarity theory. [less ▲]

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See detailCritical role of oxygen photoreduction downstream of PSI in Symbiodinium: photoprotection, energetic adjustement and ROS production
Roberty, Stéphane ULg; Bailleul, Benjamin; Berne, Nicolas ULg et al

Conference (2015, August)

The ecological success of symbiotic cnidarians (reef building-corals and sea anemones) relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium ... [more ▼]

The ecological success of symbiotic cnidarians (reef building-corals and sea anemones) relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium. Photosynthetic organisms have evolved various photoprotective and regulatory mechanisms to cope with changing and high light intensities, but the nature and relative amplitude of these mechanisms is still a matter of debate in Symbiodinium. Few studies showed that molecular oxygen (O2) can be an efficient electron sink during photosynthesis in Symbiodinium, with an O2 uptake capacity that could represent up to half the maximum O2 evolution. In addition, members of clade A Symbiodinium were proposed to possess enhanced capabilities for alternative photosynthetic electron flows. In this work, the amplitude of photosynthetic alternative electron flows to oxygen (chlororespiration, Mehler reaction, mitochondrial respiration) and PSI cyclic electron flow were investigated in Symbiodinium strains belonging to different Clades (A, B and F). Joint measurements of oxygen evolution, PSI and PSII activities allowed us to demonstrate that photoreduction of oxygen downstream PSI by the so-called Mehler reaction is the main alternative electron sink at the onset and steady state of photosynthesis in all strains1. This mechanism in Symbiodinium sustains significant photosynthetic electron flux under high light, thus acting as a photoprotective mechanism and modifying the ratio of ATP/NADPH to match the requirements of carbon reduction. At higher temperature (26 to 33°C), the amplitude of Mehler reaction was still significantly increased but the capacity of enzymes responsible for superoxide detoxification largely decreased. This imbalance generated twice more ROS than during the treatment at 26°C, suggesting that under conditions known to induce coral bleaching, the photoprotective role of Mehler reaction can no longer be maintained, at least at short term. [less ▲]

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See detailTime-averaged phase-stepped ESPI with CO2 laser and shearography in the visible for identification of vibration mode shapes
Vandenrijt, Jean-François ULg; Thizy, Cédric ULg; Georges, Marc ULg

in Mendoza Santoyo, Fernando (Ed.) SPECKLE 2015: VI International Conference on Speckle Metrology (2015, August)

We present investigation of interferometric methods for vibration mode identification to be applied on shakers in industrial environment. We consider long wave infrared ESPI in time-averaged mode with the ... [more ▼]

We present investigation of interferometric methods for vibration mode identification to be applied on shakers in industrial environment. We consider long wave infrared ESPI in time-averaged mode with the use of phase-stepping which allows transforming Bessel fringes, typical to the time averaging, into phase values which provide a better way for identification of vibration mode shapes. The use of long laser wavelength allows measuring larger amplitudes of vibrations compared to what is achieved in visible light. Also longer wavelengths allow lower sensitivity to external perturbations. Time-averaged phase-stepped shearography in visible is also used as a compared alternative to LWIR ESPI for working in industrial environments. Although not demonstrated here, an interesting feature for the future investigations on LWIR ESPI is its potentiality of simultaneous temperature measurement during vibrations [less ▲]

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See detailEffects of Music and Language Expertise on the Implicit Learning of Musical and Linguistic Structures?
Larrouy, Pauline ULg; DeChristen, Eleonore; Kolinsky, Régine

Poster (2015, August)

1. Background The cognitive consequences of music and language expertise are rarely compared. Recently, we observed different profiles in music and language experts in implicit learning of linguistic ... [more ▼]

1. Background The cognitive consequences of music and language expertise are rarely compared. Recently, we observed different profiles in music and language experts in implicit learning of linguistic structures of sung material (Larrouy-Maestri, Leybaert, & Kolinsky, 2013), with music experts performing better. Yet, as the language experts were speech therapists, this could reflect their formal, late language training. 2. Aims We aimed at comparing informal vs. formal language training and at examining the effect of dual expertise (in music and language) on the implicit statistical learning of musical and linguistic structures. We therefore used the sung material of Larrouy-Maestri et al. (2013) and tested the ability of music and/or language experts as well as of dual experts to implicitly learn the linguistic and/or musical structure of this material. 3. Method 14 music experts, 14 bi- or multi-linguals and 8 dual experts (bi- or multi-linguals also experts in music) were asked to listen attentively to 7.30 min of a continuous stream made out of 6 trisyllabic nonsense “words” sung on 6 three-tone melodies. Each “word” (defined by transitional probabilities) carried its specific melody, as melodic and linguistic transitional probabilities were congruent. A two-alternative forced-choice required choosing between “words” and “partwords”, either spoken (in the linguistic test) or instrumental (in the music test) was used to test participants’ learning of the linguistic or melodic structure. 4. Results Expertise modulated performance in the linguistic test when including the speech-therapists of our previous study (F(3, 49) = 5.92, p = .002, η2 = 0.28), who performed the worst. In the musical test, there was no significant group effect (p = .25), but one-sample t-tests showed that only the dual experts performed above chance, with 62.5% correct (p < .01). 5. Conclusions Whereas informal language training and music expertise lead to similar abilities to implicitly learn linguistic - but not musical - structure, this was not the case of formal language expertise. The combination of music and informal language expertise led to a particular profile, i.e., to the ability to learn simultaneously the musical and linguistic structures of sung material. [less ▲]

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See detailThe Hydroxyl Nightglow Emissions on Earth, Venus and Mars
Soret, Lauriane ULg; Gérard, Jean-Claude ULg; Piccioni, G. et al

Poster (2015, August)

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See detailHabitat use of the endangered Lepilemur mittermeieri - Northwest Madagascar
Wilmet, Leslie ULg; Vermeulen, Cédric ULg; Beudels-Jamar, Roseline C et al

Conference (2015, August)

Genus Lepilemur is exemplary of the endemic mammalian fauna of the island of Madagascar. Sportive lemurs have small distribution ranges, and fairly small total populations and are particularly negatively ... [more ▼]

Genus Lepilemur is exemplary of the endemic mammalian fauna of the island of Madagascar. Sportive lemurs have small distribution ranges, and fairly small total populations and are particularly negatively affected by deforestation and habitat fragmentation. Our research focus on a poorly-known taxon, Lepilemur mittermeieri, whose distribution range is located on the Ampasindava peninsula in the northwest Madagascar. It has been described in 2006 on the basis of genetic material only. Since then, no further research has been conducted and general information of this endangered species is urgently requested. We will present our global project as well as the results of a second field mission conducted from March to June 2015 in order to specifically 1) investigate habitat use of 8 radio-collared Lepilemur mittermeieri by the analysis of their home range, feeding ecology and sleeping sites characteristics and 2) to complete forest characterization of the home range of each radio-collared animal. This study is conducted on the Ampasindava peninsula, a priority area for Malagasy conservation. [less ▲]

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See detailSpecies-rich anthropogenic grasslands and the problem of afforestation
Buisson, Elise; Le Stradic, Soizig ULg; Alvarado, Swanni et al

Conference (2015, August)

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See detailBifurcation analysis of a spacecraft structure using the harmonic balance method
Detroux, Thibaut ULg; Renson, Ludovic ULg; Masset, Luc ULg et al

in Proceedings of the ASME 2015 International Design Engineering Technical Conferences (2015, August)

The harmonic balance (HB) method has been widely used in the past few years, as a numerical tool for the study of nonlinear models. However, in its classical formulation the HB method is limited to the ... [more ▼]

The harmonic balance (HB) method has been widely used in the past few years, as a numerical tool for the study of nonlinear models. However, in its classical formulation the HB method is limited to the approximation of periodic solutions. The present paper proposes to extend the method to the detection and tracking of bifurcations in the codimension-2 system parameters space. To validate the methodology, the forced response of a real spacecraft is examined. The paper first provides some numerical evidence of the presence of quasiperiodic oscillations and isolated solutions. It then demonstrates how the tracking of Neimark-Sacker and fold bifurcations can help get a deeper understanding of these attractors. [less ▲]

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See detailHow can phenology contribute to ecological restoration?
Buisson, Elise; Alvarado, Swanni; Le Stradic, Soizig ULg et al

Conference (2015, August)

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See detailLes recherches sur la médecine dans l’Égypte gréco-romaine au Centre de Documentation de Papyrologie Littéraire (CEDOPAL) de l’Université de Liège
Marganne, Marie-Hélène ULg

in Histoire des Sciences Médicales (2015, August), 49(2), 233-237

The paper presents the research on medicine in Greco-Roman Egypt conducted in the last forty years at the Centre de Documentation de Papyrologie Littéraire (CEDOPAL) at the University of Liège. It ... [more ▼]

The paper presents the research on medicine in Greco-Roman Egypt conducted in the last forty years at the Centre de Documentation de Papyrologie Littéraire (CEDOPAL) at the University of Liège. It describes the main results obtained by deciphering, editing, translating and commenting Greek and Latin medical papyri, be they literary, documentary or magical. [less ▲]

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See detailHow do “scoops” influence the perception of singing accuracy?
Larrouy, Pauline ULg; Pfordresher, Peter

Conference (2015, August)

When we listen to a singer, a large amount of time-varying information is available on which evaluations of accuracy may be based. Most analyses of singing accuracy focus on relatively steady portions of ... [more ▼]

When we listen to a singer, a large amount of time-varying information is available on which evaluations of accuracy may be based. Most analyses of singing accuracy focus on relatively steady portions of sung notes, eliminating “scoops” of pitch that often occur at note beginnings and endings. However, it is likely that these scoops contribute to judgments of accuracy. We report results of three experiments designed to address the relative contribution of these scoops in contrast to a steady central portion of sung notes. Participants rated the pitch accuracy of 4-tone melodies where the 3rd tone was manipulated with respect to its center region (either correct, 50 cents sharp, or 50 cents flat) as well as the presence of a scoop at the start and/or the end of the tone, varying with respect to direction. We were particularly interested in contrasting scoops that maintained ‘continuity’ between tones (e.g., scooping up for an ascending interval) versus those that highlighted distinctions (the opposite). Further analyses evaluated whether reactions to scoops indicate a tendency to perceive the average pitch across the entire tone, or to treat scoops versus the tone’s center as separate features. Results suggest that listeners respond to scoops in a way that goes beyond role in forming the average pitch across a tone. Listeners respond differently to scoops at the beginning versus the end, showing more sensitivity to ending scoops. Furthermore, listeners do not necessarily prefer scoops that preserve continuity. Taken together, these results demonstrate that continuous time-varying pitch information is an important indicator of perceived singing accuracy, and should be considered more fully when assessing singing ability. [less ▲]

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See detailNew insight in lymnaeid snails (Mollusca, Gastropoda) as intermediate hosts of Fasciola hepatica (Trematoda, Digenea) in Ecuador
Caron, Yannick ULg; Celi-Erazo, Maritza; Hurtrez-Boussès, Sylvie et al

Conference (2015, August)

Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts are scarce in Ecuador. During 3 months, lymnaeid snails were ... [more ▼]

Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts are scarce in Ecuador. During 3 months, lymnaeid snails were sampled (n=1482) in Pichincha province in two sites located in a highly endemic area. The snails were identified (based on morphology and ITS2 sequences) and the infection status was established through microscopic dissection and a multiplex PCR-based technique. If morphologic-based techniques were not useful to accurately named the one species collected, alignment study ascribed it to L. schirazensis. Rediae were observed in 1.75 % (26/1482) and Fasciola sp. DNA was detected in 6% (89/1482) of the collected snails. The COX1 region permitted the parasite species identification: F. hepatica. The relative sensitivity and specificity of the microscope related to the PCR results was 25.84% and 99.78% respectively. The mean size of the snails recorded positive for F. hepatica through crushing and microscopy was significantly higher than the mean size of negative snails. There was not such difference in PCR positive snails. The role of G. schirazensis as an intermediate host of F. hepatica in Ecuador is discussed and a hypothesis of an adaptation of the snail to the trematoda is formulated. For the first time, an epidemiological survey, based on molecular biology-based techniques assessed the role of lymnaeid snail in the epidemiology of fasciolosis in Ecuador. [less ▲]

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See detailThe hidden face of the human macrophage chitotriosidase: taking a new look at this enzyme based on the biochemical and phylogenomic analysis of its chitin binding domain
Crasson, Oscar ULg; Legrand, François; Léonard, Raphaël et al

Poster (2015, August)

Carbohydrates recognition is a critical process involved in numerous aspects of the cell biology such as inflammation, innate immune responses and proliferation. Chitin is an homopolysaccharide composed ... [more ▼]

Carbohydrates recognition is a critical process involved in numerous aspects of the cell biology such as inflammation, innate immune responses and proliferation. Chitin is an homopolysaccharide composed of β-1,4-linked N-acetylglucosamine (GlcNAc) units that is an abundant structural component of various infectious organisms like protozoans, nematodes and fungi. As there is no endogenous chitin produced by mammals, this polymer appeared to be a strategic target for innate immune agents which is why various carbohydrate binding proteins, associated or not with catalytic domains, are synthetized by plants and animals and are known to play a crucial role in innate immunity. The macrophage chitotriosidase (HCHT) is one of the three active chitinases synthetized by humans and has triggered significant attention recently due to its association with various inflammatory disorders. HCHT belongs to the Glycosyl Hydrolase family 18 (GH18) and is known to be involved in innate immunity. Nevertheless, its precise physiological function remains unclear. As numerous GHs, HCHT is a modular protein composed of a catalytic domain (GH18) associated to a Carbohydrate Binding Module (CBM) which is essential to hydrolyse crystalline chitin. If the catalytic domain GH18 is highly common in other GHs from animals, plants, fungi, bacteria, archea and viruses, its CBM (named ChBD) is much less conserved which makes the association between these two domains particularly intriguing. This work aims to demystify HCHT’s physiological function. Firstly, using competitive inhibition assays, we have highlighted the ability of ChBD to interact with chitooligosaccharides (GlcNAc1-2-4-6) which suggests that ChBD can potentially act as a lectin domain. Secondly, to better understand the molecular basis for chitin recognition, we have used homology modelling to build, with high confidence, the 3D structure model of ChBD. Based on this model, a specific set of residues has been selected for alanine scan mutagenesis which has allowed us to define the minimum chitin binding interface of the protein. Thirdly, Phylogenomic studies were performed to analyse the evolutionary history of the isolated catalytic and ChBD domains and understand how these domains were combined. Based on all these results, we discuss a new way of looking at HCHT where its ChBD would be the key determinant that has guided the catalytic domain from a basic metabolic function to a critical component of innate immunity in human. Finally, we propose a mechanism that explains how this enzyme could act at the molecular level to defend us against chitin-containing pathogens. [less ▲]

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See detailMathematical modeling of extracorporeal CO2 removal
Habran, Simon ULg; Dauby, Pierre ULg; Desaive, Thomas ULg et al

Poster (2015, August)

Extra¬cor¬poreal CO2 removal devices (ECCO2R) can be used in clinics to decarboxylate blood externally for patients suffering from pulmonary insufficiencies like acute respiratory distress syndrome. In ... [more ▼]

Extra¬cor¬poreal CO2 removal devices (ECCO2R) can be used in clinics to decarboxylate blood externally for patients suffering from pulmonary insufficiencies like acute respiratory distress syndrome. In this work, a model of the respiratory system coupled with such a device is proposed to analyze the decrease of CO2 partial pressure in blood as a function of blood flow through the device. This model provides a mathematical tool which could help clinicians to choose the optimal settings of ECCO2R. [less ▲]

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See detailModelling of the Nonlinear End-Systolic Pressure-Volume Relation and Volume-at-Zero-Pressure in Porcine Experiments
Davidson, Shaun M.; Kannangara, D. Oliver; Pretty, Christopher G. et al

in Proceedings of the 37th International Conference of the IEEE Engineering in Medicine and Biology Society (2015, August)

The End-Systolic Pressure-Volume Relation (ESPVR) is generally modelled as a linear relationship between P and V as cardiac reflexes, such as the baroreflex, are typically suppressed in experiments ... [more ▼]

The End-Systolic Pressure-Volume Relation (ESPVR) is generally modelled as a linear relationship between P and V as cardiac reflexes, such as the baroreflex, are typically suppressed in experiments. However, ESPVR has been observed to behave in a curvilinear fashion when cardiac reflexes are not supressed, suggesting the curvilinear function may be more clinically appropriate. Data was gathered from 41 vena cava occlusion manoeuvres performed experimentally at a variety of PEEPs across 6 porcine specimens, and ESPVR determined for each pig. An exponential model of ESPVR was found to provide a higher correlation coefficient than a linear model in 6 out of 7 cases, and a lower Akaike Information Criterion (AIC) value in all cases. Further, the exponential ESPVR provided positive V0 values in a physiological range in6 out of 7 cases analysed, while the linear ESPVR produced positive V0 values in only 3 out of 7 cases, suggesting linear extrapolation of ESPVR to determine V0 may be flawed. [less ▲]

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See detailPotential of visible-near infrared spectroscopy for the characterization of butter properties
Troch, Thibault ULg; Baeten, Vincent; Dehareng, Frédéric et al

in Book of Abstracts of the 66th Annual Meeting of the European Federation of Animal Science (2015, August)

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See detailGeophysical Investigation of the Pb-Zn deposit of Plombières, Belgium
Evrard, Maxime ULg; Pirard, Eric ULg; Nguyen, Frédéric ULg

in André-mayer, anne-Sylvie; Cathelineau, Michel; Muchez, Philippe (Eds.) et al Mineral resources in a sustainable worl, proceeding, volume 5 (2015, August)

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See detailHow novice and expert drivers adjust their driving behavior when they feel drowsy?
Berastegui, Pierre ULg; Piette, Christine; François, Clémentine ULg et al

Poster (2015, July 29)

This paper aims to explore adaptive behaviors developed by drivers to prevent drowsiness. Specifically, we postulate that driving expertise is associated with better drowsiness awareness, allowing experts ... [more ▼]

This paper aims to explore adaptive behaviors developed by drivers to prevent drowsiness. Specifically, we postulate that driving expertise is associated with better drowsiness awareness, allowing experts to adequately adjust their driving behaviors when they feel drowsy. The present study was carried on a high-fidelity driving simulator coupled with an innovative system allowing objective sleepiness assessment based on EEG and Eye-tracking data. The Karolinska Sleepiness Scale was used to evaluate subjective drowsiness. The ratio between objective and subjective assessments gave an indicator of drowsiness awareness. Standard Deviation of Lateral Position (SDLP) was used as a measure of performance while driving speed and ocular fixations were recorded in order to highlight adaptive behaviors. 16 subjects were recruited from general population and categorized in two groups of expertise based on the Belgian Institute for Road Safety’s criteria. Our results show that expert drivers show better drowsiness awareness than novices and mobilize speed increasing and vigilance reallocation strategies to maintain satisfactory level of drowsiness. [less ▲]

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See detailProbing the conformational changes during desolvation of ions using orthogonal mobility methods (CE-IMS)
Far, Johann ULg; Kune, Christopher ULg; Delvaux, Cédric ULg et al

Poster (2015, July 29)

The transfer of ions from the solution to the gas phase is a critical step to produce « native species ». Coming from a highly solvating medium, ionic species will tend to find a new equilibrium ... [more ▼]

The transfer of ions from the solution to the gas phase is a critical step to produce « native species ». Coming from a highly solvating medium, ionic species will tend to find a new equilibrium conformation in the gas phase. The pathway to reach the thermodynamically stable conformation involves crossing potential barriers of different heights. When these barriers are too high compared to the internal energy of the ions, it will result in “partial memories” (as structural preservation) of the conformation in solution. In order to evaluate the effect of the solvent evaporation and of the various collision processes encountered by the ions in the mass spectrometer, we developed two strategies: The first strategy consists in comparing in a single experiment the shape of the ions in solution and in the gas phase. Data are obtained by coupling capillary electrophoresis with Ion Mobility Mass Spectrometry. Drift times in solution and in the gas phase are directly compared. Deviations from their correlation points out changes in folding upon desolvatation. Preliminary results show that among peptides issued from tryptic digest of BSA some of them clearly change their conformation during desolvatation. The second strategy consists in probing changes of conformation once the ions are in the gas phase. The ions are rapidly heating by collisions ions during their transfer to the IMS. The heating is obtained by increasing their collision energy, rapidly followed by thermalisation in the IMS cell. The ions may be kinetically trapped in their new conformations. This allows comparing barriers between different ions geometries. In summary this work intends to evaluate the extent of conformational “memory” of the ions of different nature for best experimental condition allowing “native mass spectrometry” [less ▲]

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See detailCONTRIBUTION OF ION MOBILITY FOR STRUCTURAL ANALYSIS AND ANALYTICAL CHEMISTRY: THE USE OF PROBE LIGANDS AND SELECTIVE IMS SHIFT REAGENTS
Kune, Christopher ULg; Far, Johann ULg; Delvaux, Cédric ULg et al

Conference (2015, July 28)

Ion mobility is a gas phase separation technique sensitive to the Collisional Cross Section (CCS) difference of ions (as CCS/ΔCCS). It discriminates isobaric and isomeric ions when CCS difference is ... [more ▼]

Ion mobility is a gas phase separation technique sensitive to the Collisional Cross Section (CCS) difference of ions (as CCS/ΔCCS). It discriminates isobaric and isomeric ions when CCS difference is larger than the instrumental resolution (roughly 50). To overcome the usual resolution of ion mobility (IM), it is necessary to use new strategies in addition to the optimization of the ion mobility parameters. This work proposes a new method to bypass this limitation while providing additional structural information by the use of Selective Shift Reagents (SSR). A SSR can specifically bind with a target ion depending of their physicochemical properties like chemical groups, steric hindrance, polarity, space charge effects… In this strategy, the choice of SSR is fundamental. SSR could be empirically selected or assisted and designed by computational chemistry prediction. SSR can be used as a chemical probe which can support physicochemical properties and help or confirm hypotheses for structural elucidation. They can also drastically change the CCS of a target ion present in a complex mixture (e.g. biological origin sample) as shifting reagent for e.g. quantification purpose. Models used for the proof of concept have been selected in order to lead to an expected or predictive result. Firstly crown ethers have been used as SSR in IMS to shift the protonated valine drift time from the protonated proline drift time according to their chemical groups and especially amino groups. The selectivity of SSR leads to an improved separation between valine and proline. Secondly three structural isomers of diaminonaphthalene were investigated experimentally and theoretically using computational chemistry support after the addition of different crown ethers or β-cyclodextrin as SSR to improve the separation of these isomers by IMS. Finally, the concept of SSR was successfully applied to biological origin samples to elucidate structure and allows the quantification of selenium (Se) containing compounds present in an aqueous extract of Se rich yeast. [less ▲]

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See detailSedimentological and geochemical evidence to detect arid periods recorded in wadi deposits: a case study from northern Morocco
El Ouahabi, Meriam ULg; Bartz, Melanie; Rixhon, Gilles et al

Poster (2015, July 27)

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See detailIdentification of VZV ORF9p potential cellular partners that could be important for the viral egress.
Lebrun, Marielle ULg; riva, laura; Rambout, Xavier ULg et al

Poster (2015, July 26)

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate ... [more ▼]

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate of the viral kinase ORF47p and that its ORF47p-dependent phosphorylation is important for the secondary envelopment process. We also have identified an acidic cluster (AC) within the protein that is important for its correct localization in the infected cells and for the interaction with ORF47p. The recombinant VZV expressing ORF9p-ΔAC presents an accumulation of capsids in the perinuclear space. ORF9p seems then to play an important role in several steps of the egress process. In this context, we sought to identify cellular partners of ORF9p that might be important for these functions. We performed a yeast two hybrid screen against the human ORFeome 5.1. and picked out 44 candidates among which 5 proteins playing roles in membrane organization and targeting. We currently are trying to confirm these interactions in infected cells and to assess the role of these interactions for the viral lytic cycle. [less ▲]

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See detailEthnic Differences in Travel Time Expenditure
Cools, Mario ULg; Eftekhar, Hamed ULg

in Proceeding of the 14th International Conference on Travel Behaviour Reresearch (IATBR 2015) (2015, July 23)

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See detail« Rien dans tout cela où ne soit Zeus ». L'eau du ciel, un domaine exclusivement jovien ?
Lebreton, Sylvain ULg

Conference (2015, July 23)

Si les anciens Grecs ont donné en partage leurs paysages aquatiques – sources, fleuves et rivières, mers et océans – à un grand nombre de divinités différentes, il semble bien qu'ils faisaient de Zeus le ... [more ▼]

Si les anciens Grecs ont donné en partage leurs paysages aquatiques – sources, fleuves et rivières, mers et océans – à un grand nombre de divinités différentes, il semble bien qu'ils faisaient de Zeus le seul dieu compétent en ce qui concerne la pluie. Depuis le « Zeus pleut » homérique, la littérature grecque abonde en effet de témoignages suggérant ce rapport d'exclusivité. Sans prétendre changer fondamentalement la donne, une analyse des données cultuelles – à partir des sources épigraphiques notamment – permettra sans doute de préciser, d'ajuster cet état de fait qui semble de fait souffrir de bien peu d'exceptions. Un examen systématique des nombreuses épiclèses « pluvieuses » du polythéisme hellénique tend en effet à confirmer le caractère spécifiquement jovien de ce domaine de compétence – les autres divinités ne semblant y intervenir qu'à ses marges (Apollon et la grêle par exemple). Mais le constat de la richesse et de la diversité de ces épithètes cultuelles constitue surtout le marchepied nécessaire à une réflexion sur les fondements et les modalités des adresses des Grecs à leurs dieux – leur Zeus en l'occurrence – pour tenter de gérer au mieux l'eau du ciel. Une étude exhaustive de ces épiclèses et des données cultuelles qui leur sont associées permet en effet de souligner en outre les spécificités de ce champ de compétence divin, dans le temps – à la fois sur le plan du temps rituel, mais aussi des évolutions depuis l'époque archaïque jusqu'à la période impériale – comme dans l'espace. Sur ce dernier point en effet, force est de constater que les épiclèses pluvieuses de Zeus ont partie liée à l'emprise spatiale du dieu, sommitale en l'occurrence. Plus globalement, elles ne se limitent pas à ce strict domaine d'intervention ; inversement, d'autres épithètes non explicitement pluvieuses peuvent aussi désigner le Zeus faiseur de pluie. Ainsi, ces épiclèses se trouvent au sein d'un réseau de champs de compétences joviens qui ne sont pas isolés, mais bien articulés les uns aux autres. Et c'est dans ce réseau qu'il est possible de déceler, in fine, la cohérence de cette construction culturelle qu'est Zeus. Sans pouvoir prétendre aborder l'ensemble des conceptions grecques en matière de pluie, ce parcours à travers les épiclèses pluvieuses de Zeus permettra néanmoins d'évoquer quelques dossiers relevant tant du rite (cas de la danse de la pluie, cadres rituels, calendaires par exemple), que de la pluviométrie (précipitations et sécheresse) ou encore de l'agriculture, le tout s'inscrivant dans les récents débats conceptuels relatifs à la cohérence du polythéisme. Compte tenu de sa richesse, la documentation attique sera privilégiée, sans toutefois négliger les parallèles extra-athéniens, depuis l'époque archaïque jusqu'au Haut-Empire. [less ▲]

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See detailImpact of phenotypic heterogeneity and metabolic specialisation on metabolic engineering strategies: case of study of E.coli as a representative microbial cell factory
Brognaux, Alison ULg; Delepierre, Anissa ULg; Pecheux, Hélène ULg et al

Conference (2015, July 21)

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant ... [more ▼]

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant protein and pDNA production in bioprocesses. This phenotypic heterogeneity, first due to the noise, is reinforced by environmental heterogeneities occurring at large scale during fed-batch processes. This phenotypic heterogeneity has been tracked according to GFP reporter strains (biosensors) that circulate in the bioreactor and encounter environmental heterogeneities. First, we have highlighted the simultaneous occurrence of several phenotypes with distinct metabolic functions. Indeed, a diversity of glucose uptake strategies has recently been noticed with the PtsG and MglABC transporters. Moreover, when E.coli encounters zones of glucose excess, acetate is produced through the overflow metabolism. Only the sub-population with high acs expression (acetate transporter) could consume this acetate. GFP reporter strains have thus been constructed for PtsG, MgIABC and acs genes. In addition of the stable GFP, two destabilized GFP variants for each gene have been used to obtain more instantaneous responses. The response of these biosensors have been followed by on-line flow cytometry. In the end, this experimental strategy for direct phenotyping at the single cell level will also be used to investigate the impact of metabolic engineering strategies on phenotypic heterogeneity, robustness and fitness of microbial population in industrial conditions. [less ▲]

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See detailExploratory study of narratives in children with attention deficit hyperactivity disorder
Boulard, Aurore ULg; Pignatiello, Laure ULg; Leclercq, Cédric

Poster (2015, July 21)

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See detailA viscoelastic-viscoplastic-damage constitutive model based on a large strain hyperelastic formulation for amorphous glassy polymers
Nguyen, Van Dung ULg; Morelle, Xavier; Lani, Frédéric et al

in proceedings of the 20th International Conference on Composite Materials, Copenhagen, Denmark, 19-24th July 2015 (2015, July 20)

The aim of this work is to develop an efficient large-strain hyperelastic constitutive model for amorphous polymers in the glassy state. These materials exhibit a complex rate- and pressure-sensible ... [more ▼]

The aim of this work is to develop an efficient large-strain hyperelastic constitutive model for amorphous polymers in the glassy state. These materials exhibit a complex rate- and pressure-sensible behavior in both elastic and plastic regimes. After an initial linear elastic region, a nonlinear stage continues until reaching a peak stress, which is followed by a softening stage. At large strains, when the softening is saturated, a re-hardening stage is reached. The viscoelastic effect is captured using the generalized Maxwell model. The viscoplastic effect is considered using a Perzyna-type flow rule incorporating a pressure sensitive yield surface and a non-associated flow potential. This yield surface is extended from the Drucker-Prager one. The saturated softening phenomenon is modelled using an isotropic numerical damage variable progressed by a saturated softening law. With the introduction of the damage parameter, a non-local implicit gradient damage model is used to avoid the loss of the solution uniqueness. Through experimental comparisons, it is shown that the proposed model has the ability to model the complex mechanical responses of amorphous glassy polymers. [less ▲]

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See detailFunctionality of microbial phenotypic heterogeneity in bioprocessing conditions: an analysis based on the use of on-line flow cytometry
Delepierre, Anissa ULg

Conference (2015, July 20)

Microbial phenotypic heterogeneity is known to be naturally present in isogenic population and can be attributed to the stochastic nature of the biochemical reactions. An important question at this level ... [more ▼]

Microbial phenotypic heterogeneity is known to be naturally present in isogenic population and can be attributed to the stochastic nature of the biochemical reactions. An important question at this level was to determine whether such stochastic behavior exhibits some functionality, i.e. how single cell heterogeneity leads to population level strategies. One of this strategies, called bet-hedging, is known to give a competitive advantage to the population, by leading for example to a persistent phenotype able to survive to antibiotics exposure. Among the single cell toolbox available for the analysis of phenotypic heterogeneity, flow cytometry present the advantage of being compatible with bioprocess cultivation tools. In this work, we present an on-line analytical workflow based on automated flow cytometry that can be used to monitor simultaneously several bioreactors, testing different bioreactor operating conditions, in combination with fluorescent transcriptional reporter strategies: promoter involved in metabolism fused to a gene expressing an unstable variant of GFP , and viability fluorescent tagging: propidium iodide uptake, correlated with membrane permeability. [less ▲]

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See detailTowards an "African Stylistics": Apprehending Cross-Cultural Creativity in the Works of Chris Abani
Tunca, Daria ULg

Conference (2015, July 18)

Anglophone African literatures have often been praised for their linguistic originality. More often than not, critics interested in the stylistic inventiveness of works from the continent have focused ... [more ▼]

Anglophone African literatures have often been praised for their linguistic originality. More often than not, critics interested in the stylistic inventiveness of works from the continent have focused their attention on these texts’ specifically “African” features, from the use of proverbs to the presence of words from indigenous languages. While these scholarly studies have done much to demonstrate the richness of African aesthetic standards, they have also tended to obscure other facets of the creativity of African writers who, just like their counterparts all over the world, make ample use of such devices as metaphor, irony, and unreliable narration. After a brief examination of the methodological and epistemological issues that have shaped the elusive field of “African stylistics”, I propose to investigate how contemporary stylistic theories may contribute to the understanding of the multiple forms of creativity found in the works of the US-based Nigerian writer Chris Abani. A self-proclaimed “global Igbo” (after the name of his father’s ethnic group), Abani boldly combines in his work African cosmology with influences from the Catholic and Buddhist traditions, also using formal devices – such as minor sentences and poetic metaphors – whose significance can only be fully appreciated through extensive stylistic analysis. Mainly focusing on Abani’s novella Becoming Abigail (2006), I will suggest that a combination of traditional culture-oriented approaches to African literatures and more typically “mainstream” stylistic techniques is needed to apprehend the Nigerian writer’s complex cross-cultural worldview. [less ▲]

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See detailCombining mindfulness and ACT to learn how to manage emotions and to engage in valued activities: Assessment of the feasibility of a training group and its efficiency
Wagener, Aurélie ULg; Dierickx, Christophe; Blairy, Sylvie ULg

Poster (2015, July 18)

BACKGROUND Managing painful emotions could be an issue for a lot of adults. Indeed, learning how to manage painful emotions is an often-requested demand in psychotherapy. Mindfulness-based programs and ... [more ▼]

BACKGROUND Managing painful emotions could be an issue for a lot of adults. Indeed, learning how to manage painful emotions is an often-requested demand in psychotherapy. Mindfulness-based programs and acceptance and commitment therapy (ACT) offer useful tools which aim to guide in this learning process. ACT also provide guidelines to engage in valued activities. In order to help community adults to manage their painful emotions and to engage themselves in valued activities, we offer training group cycles combining tools of mindfulness-based programs and ACT. This study aims to assess the feasibility of such training groups and their efficiency. METHODS A longitudinal design with three assessment-times (T0, T1 and T2) is employed. Participants to the training group attend to three three-hours training sessions on a six-weeks period. They are assessed before the training sessions (T0), directly after (T1) and at three-months follow-up (T2). Questionnaires assess these variables: sociodemographic data, mood, mindfulness, psychological flexibility, cognitive coping strategies and behavioural activation. Student t tests for paired samples are conducted. RESULTS Fifty-four adults participated to four training cycles (the cycles are all identical). Until now, 28 participants (21 women) completed the T0 and the T1 (mean age = 41.43, SD = 11.83). Student t test indicate a significant decrease of depression (t(25) = 4.53, p < 0,001), anxiety (t(25) = 6.23, p < 0.001) and non-adaptive cognitive coping strategies (t(24) = 3.76, p < 0.001). Student t test also indicate a significant increase in mindfulness (t(26) = -3.87, p < 0.001), psychological flexibility (t(26)) = -5.48, p < 0.001) and behavioural activation (t(26) = -4.86, p < 0.001). DISCUSSION Preliminary results indicate the feasibility of training groups combining tools of mindfulness-based programs and ACT. Results show a decrease in several variables (depression, anxiety and non-adaptive cognitive coping strategies) and an increase in other variables (mindfulness, psychological flexibility and behavioural activation). These results seem to indicate that participants benefit from the training groups. Data collection is still ongoing and a control group (waiting-list) is currently being composed. Results and clinical implications will be further discussed during the congress. [less ▲]

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See detailVirtual plaster cast: digital 3D modelling of paws and tracks via photogrammetry
Marchal, Antoine ULg; De Bruyn, Nico; Lejeune, Philippe ULg

Conference (2015, July 17)

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See detailIsolation and identification of potential antimalarial compounds from endemic plants of Reunion Island
Bordignon, Annélise ULg

Poster (2015, July 16)

Malaria is known as the most important parasitic disease around the world with 584 000 malaria deaths worldwide in 2013 [1]. Due to the problem of increased parasite resistance, natural products from ... [more ▼]

Malaria is known as the most important parasitic disease around the world with 584 000 malaria deaths worldwide in 2013 [1]. Due to the problem of increased parasite resistance, natural products from endemic plants of Reunion Island, hot spot of promising biodiversity, could represent an important source of new antimalarial drugs. The aim of this thesis research focuses on the evaluation of potential antiplasmodial activity of medicinal plants from Reunion Island. A global screening of plants extracts from Reunion Island was performed on Plasmodium falciparum 3D7 chloroquine-sensitive strain revealed by colorimetric method as described in previous reports [2]. Monimia rotundifolia was then selected due to its promising in vitro activity against Plasmodium. Bioguided fractionation was realized using Prep HPLC techniques and led to the isolation of aporphine-type alkaloids from Monimia rotundifolia leaves dichloromethane extract. Further investigations are in process to confirm the antiplasmodial activities of these alkaloids and to determine their structures. References: [1] WHO, World Malaria report 2014. [2] Jansen O. et al., Evaluation of 13 selected medicinal plants from Burkina Faso for their antiplasmodial properties. J Ethnopharmacol 2010, 130:143-150. [less ▲]

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See detailMetabolomics analysis of Galium odoratum (L.) Scop.: impact of the plant population origin and growth conditions.
Ledoux, Allison ULg; Martin, Bertrand; De Tullio, Pascal ULg et al

Poster (2015, July 16)

Galium odoratum is a plant used in traditional medicine and to prepare beverages. This work aimed at studying the impact of plant origin and growth conditions on the metabolite content of the plant ... [more ▼]

Galium odoratum is a plant used in traditional medicine and to prepare beverages. This work aimed at studying the impact of plant origin and growth conditions on the metabolite content of the plant. Material and methods- Aerial biomass of Galium odoratum was collected from five natural populations (in situ conditions) and from controlled environment (ex situ conditions). Results- Quantitative analysis of selected phytochemicals including phenylpropranoids and iridoids showed clear differences between the plants from nature and those of controlled growth conditions as well as internal variation within the group. The metabolomic approach emphasized the decrease of the secondary metabolites pool paralleled by an increase of the carbohydrates in ex situ conditions. Conclusion- Metabolomics approaches using 1H-NMR and HPLC is worth to consider for studying the impact of climate factors on the regulation of the phytochemical profile in relation to the origin of the plant material. [less ▲]

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See detailDevelopmental profiles of GFAP-positive astrocytes in sheep cerebellum
Salouci, Moustafa ULg; Antoine, Nadine ULg; Shikh Al Sook, Mohamad Khir ULg et al

Poster (2015, July 16)

Astroglial cells make up the largest glial population in the brain and play a variety of vital functions in the development of the CNS. Defects in the development of these cells may induce various ... [more ▼]

Astroglial cells make up the largest glial population in the brain and play a variety of vital functions in the development of the CNS. Defects in the development of these cells may induce various neurodegenerative disorders and result in neural disease. The aim of this study is to investigate the normal development of astrocytes in sheep in various zones of the cerebellum during the different stages of gestation. 19 ovine fetuses, one lamb in the first postnatal week and three adult sheep. Sections of the cerebellum were embedded in paraffin and processed for immunohistochemistry for GFAP. The current study indicates that the first appearance of astrocytes occurs around the 8th week of gestation from restricted zones in the cerebellum. Bergmann cells were present around the 15th week of gestation. Our findings suggest that the maturation of astrocytes begins in the caudal parts of the cerebellum from their initial ventral regions to dorsal regions radially within the white matter followed by the more rostral parts of the cerebellum and that the astrocytes proliferate in the vermis before the cerebellar hemispheres. Our study provide a bases for future studies focusing on the pathological changes in the CNS of both human and sheep. [less ▲]

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See detailEffect of calving interval on the economic results of dairy farms based on their typology.
Dalcq, Anne-Catherine ULg; Beckers, Yves ULg; Wyzen, Benoit et al

Conference (2015, July 15)

The calving interval (CI) can influence the milk production (MP) and the economic results of a farm. This research aimed to highlight the most economically important CI, on the basis of the accounts of ... [more ▼]

The calving interval (CI) can influence the milk production (MP) and the economic results of a farm. This research aimed to highlight the most economically important CI, on the basis of the accounts of breeders. The data set contained 1,318 accounts spread between 2007 and 2012. Technical information such as mean CI of the herd, percent of cows with a CI of less than 380 d (m380), between 380 and 419 d (e380419), between 420 and 459 d (e420459) and more than 459 d (p459), mean MP of the herd; as well as typological information such as quantity of equivalent concentrate (CC), number of ares of grass (GR) and of corn silage (CS) per livestock unit (LU); and economic information such as mean gross margin per cow were available. The relation between CI and the gross margin showed that if a single economic optimum of CI cannot be determined, this optimum could depend on the typology of the farm. Therefore, 4 groups were created by using a multiple correspondence analysis, including quantity of equivalent CC, number of ares of GR and of CS per LU as variables. The first group was the most intensive one with a feeding based mostly on CC and CS; the second group was similar but less intensive. The third group was the most extensive with high GR consumption. The fourth group was characterized by a near absence of CS but more CC. Moreover, m380, e380420, e420459, p459 were transformed from quantitative to qualitative variables by using numerical classification. A qualitative variable CI profile was created as a summary of all these variables. In each group, MP was modeled using the different CI variables. The assumption behind this modeling was that for a typological profile, the breeder must have the highest MP to maximize the gross margin. These models showed that MP is maximized when p459 is lower than 26%, lower than 37%, above 27% for the group 1, 2, 3 respectively. For the group 4, the model with the variable CI profile suggested that the economic optimum of CI is intermediate. These results underlined that the economic optimum of CI is related to the typology of the considered farm. Studying individual data is a perspective to determine more precisely CI with the best economic results. [less ▲]

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See detailA general lotsizing problem with uncertain product returns
Amand, Guillaume ULg; Arda, Yasemin ULg

Conference (2015, July 15)

We consider a single-stage system that produces a range of final products. The demands of the final products are supposed deterministic over a finite planning horizon. Each unit of demand has to be ... [more ▼]

We consider a single-stage system that produces a range of final products. The demands of the final products are supposed deterministic over a finite planning horizon. Each unit of demand has to be fulfilled at the period that it appears using either the production of that period or the inventory carried over from the earlier periods. The final products can either be manufactured using purchased materials or remanufactured using remanufacturable returned products. For each final product, the manufactured and remanufactured items are perfectly substitutable. The returned products are collected at the start of each period but the quantities obtained are unknown until the collection. The return inventories accumulate as remanufacturable returned items are received. The manufacturing and remanufacturing processes of all the final products are executed on a same machine. In each time period, multiple products can be processed but the total production quantity is limited by the time availability of the machine during this period. Whenever production is switched from one final product to another, a sequence dependent setup cost is incurred and a sequence depen- dent setup time is consumed from the available time capacity. Different stochastic combinatorial optimization methods as well as dynamic programming methods are proposed, tested and compared. [less ▲]

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See detail«Aménager un environnement : bienveillance et non-vouloir»
Brahy, Rachel ULg; Servais, Véronique ULg

Conference (2015, July 14)

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See detailPersonnalité antisociale et psychopathologie
Englebert, Jérôme ULg

Conference (2015, July 14)

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes ... [more ▼]

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes contradictions propres au diagnostic qui nous mèneront à l’identification du critère « primaire » de cette entité qui est l’« incapacité à se conformer aux lois et normes sociales ». Nous confronterons ensuite à des situations cliniques l’hétérogénéité des profils pouvant répondre à ce diagnostic. Nos constats nous conduiront à mettre en doute la validité apparente du concept de personnalité antisociale, puisqu’il recouvre des modes de fonctionnement psychologique variés. La valeur discriminative faible, en matière de fonctionnement psychologique, suggère que c’est une dimension autre que psychopathologique qui organise ce diagnostic. Dénuée de toute attention pour les modes d’interactions, pour le vécu émotionnel et pour les états de subjectivité, la notion de personnalité antisociale ne porte pas d’intérêt à l’individu qu’elle catégorise, mais bien à l’acte délinquant commis par ce dernier. Nous conclurons sur le constat de l’absence de dimension psychopathologique de la personnalité antisociale, qui se révèle être un diagnostic principalement criminologique, à l’inverse des fondements de l’éthique psychopathologique. [less ▲]

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See detailEarly Carboniferous events along the north-eastern Gondwanan margin: an example from the Mobarak Formation of the Central Alborz Mountains, Northern Iran.
Sardar Abadi, Mehrdad ULg; Da Silva, Anne-Christine ULg; Poty, Edouard ULg et al

Poster (2015, July 14)

The transition from the Late Devonian to the Early Carboniferous was marked by tectonic events, environmental change and global oceanic biological turnover that influenced sedimentary regimes. The end ... [more ▼]

The transition from the Late Devonian to the Early Carboniferous was marked by tectonic events, environmental change and global oceanic biological turnover that influenced sedimentary regimes. The end-Devonian faunal extinction event, for example, eliminated most of the reef building taxa, which, coupled with an increasing rate of subsidence in response to the opening of the Paleo–Tethys and a sea-ward shift of carbonate factories during the Lower Carboniferous, led to the formation of extensive carbonate ramp platforms along the Laurasian and Gondwanan margins. This development has already been reported from the western Gondwanan and southern Laurasian margins but not from northern to north-eastern Gondwanan margin yet. We aim to improve the knowledge on the main factors controlling the development and growth of carbonate ramps during the Lower Carboniferous by examining the Alborz basin along the northern margin of Gondwana. The Lower Carboniferous Mobarak Formation records the development of a storm-sensitive pervasive carbonate factory on the southern Paleo-Tethys passive margin following the opening of the Paleo-Tethys Ocean into the Alborz basin along the northern margin of Gondwana. Four outcrops in the central Alborz Mountains were studied: the Jaban, Aroo, Shahmirzad and Labnesar sections. Four events have been described as the principal factors controlling carbonate platform evolution in the Lower Carboniferous: (1) A transgression linked to global temperature rise in the Early Tournaisian (Middle Hastarain) resulted in the formation of thick-bedded argillaceous limestones. This interval is represented by massive beds of dark mudstones–wackestones to packstones that laterally interfinger with finely laminated limestones, and with bed thickness ranging on the centimeter to meter scale. This interval correlates with Lower Tournaisian nodular to argillaceous limestones of the Moravia Basin (Czech Republic), the Rhenish Slate Mountains (Poland) and the Dinant Basin (Belgium). (2) Late Hastarian–Early Ivorian glaciations were identified in Southern Gondwana but had not been evidenced in Northern Gondwana yet. This glaciation regime is recorded through the appearance of inner-ramp channel-form facies in mid– and outer-ramp settings. (3) During Late Ivorian–Early Visean?, a differentiation block faulting regime along the basin’s margin caused uplift of the westernmost parts of the Alborz basin and resulted in a sub-marine collapse in the eastern part of the central basin. This caused vast sub-aerial exposure and brecciation the top of the Mobarak Formation at the Jaban and Aroo sections. The sub-marine collapse was recorded through the occurrence of Zoophycos bearing fine-grained limestones in the top of the Labnesar and Shahmirzad sections. (4) Tectonic activity that coincided with considerable and abrupt sea level falls as an indirect consequence of the Viséan and Serpukhovian glaciations phases. This progressive sea level drop led to the stagnation of the carbonate factory, which is expressed as an erosional surface at the top of the Mobarak Formation. [less ▲]

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See detailDevelopment of a simple approach for ultrasensitive detection of bisphenols by multiplexed surface enhanced Raman scattering
De Bleye, Charlotte ULg; Dumont, Elodie ULg; Netchacovitch, Lauranne ULg et al

Poster (2015, July 13)

A very simple, cheap and fast SERS method using functionalized silver nanoparticles was developed to detect bisphenols. This method was applied for the semi-quantitative detection of bisphenol A (BPA ... [more ▼]

A very simple, cheap and fast SERS method using functionalized silver nanoparticles was developed to detect bisphenols. This method was applied for the semi-quantitative detection of bisphenol A (BPA), bisphenol B (BPB) and bisphenol F (BPF) separately. Afterwards, a feasibility study of performing a multiplex SERS detection of BPA, BPB and BPF was successfully carried out. Finally, this developed method was applied on real samples which were solutions comprising cash receipts collected from different stores. [less ▲]

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See detailFeasibility-oriented Branching Strategies for Global Optimization
Gerard, Damien ULg; Köppe, Matthias; Louveaux, Quentin ULg

Conference (2015, July 13)

We study the spatial Brand-and-Bound algorithm for the global optimization of nonlinear problems. In particular we are interested in a method to find quickly good feasible solutions. Most spatial Branch ... [more ▼]

We study the spatial Brand-and-Bound algorithm for the global optimization of nonlinear problems. In particular we are interested in a method to find quickly good feasible solutions. Most spatial Branch-and-Bound-based solvers use a non global solver at a few nodes to try to find better incumbents. We show that it is possible to improve the branching rules and the nodes priority by exploiting the solutions from the non global solver. We also propose several smart adaptive strategies to choose when to run the non global solver. We show that despite the time spent in solving many more NLP problems in the nodes, the new strategies enable the algorithm to find the first good incumbents much faster and to prove the global optimality faster. NLP instances from the COCONUT library are benchmarked. All experiments are run using the open source solver Couenne. [less ▲]

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See detailEthnopharmacology and malaria in Africa
Frederich, Michel ULg; Jansen, Olivia ULg; Muganga, raymond et al

Conference (2015, July 12)

According to the last World Malaria Report [1], there were 584 000 deaths for 198 millions malaria cases worldwide in 2013. Particularly, the disease caused an estimated 437 000 African children died ... [more ▼]

According to the last World Malaria Report [1], there were 584 000 deaths for 198 millions malaria cases worldwide in 2013. Particularly, the disease caused an estimated 437 000 African children died before their fifth birthday, still in 2013. Malaria is caused by a parasite, Plasmodium sp. and transmitted by Anopheles mosquitoes. The problem of parasite resistance towards common available medicines such as chloroquine, mefloquine, quinine, is increasing. In this context, the vegetal kingdom remains the main source of pharmacologically active compounds against this parasitic infection as attested by the famous quinine, isolated from Cinchona sp., artemisinin extracted from Artemisia annua and also atovaquone derived from lapachol found in several Bignoniaceae. All these substances are related to plants with traditional use against fever and malaria. Beside these well-known examples, various new antiplasmodial compounds are frequently discovered from Nature, particularly following an ethnopharmacological approach, as reviewed by several authors in recent years [2-6]. Then, the pharmacological and phytochemical study of plants from traditional pharmacopoeias can be of first interest not only to discover new antimalarial “lead compounds”, but also to valorize local vegetal species whose efficacy and safety would have been demonstrated in laboratory and clinical investigations [7]. As demonstrated in several works from Willcox [8], better knowledge of plants from traditional pharmacopoeias and local valorization of validated traditional remedies in Improved Traditional Medicine (ITM) could allow the access to effective, standardized, available and affordable therapeutics for management of malaria by local populations. After this introductive section, the second part of the talk will be dedicated to the presentation of some results obtained in Liège with Dicoma tomentosa from Burkina-Faso [9], Strychnos icaja from Cameroun [10] and Terminalia mollis from Rwanda [11]. 1. WHO, World Malaria Report 2014, December 2014, Geneva (http://www.who.int/malaria/publications/world_malaria_report_2014/en/). 2. Batista R, Silva Ade J Jr, de Oliveira AB: Plant-derived antimalarial agents: new leads and efficient phytomedicines. Part II. Non-alkaloidal natural products. Molecules 2009, 14:3037-72. 3. Bero J, Frédérich M, Quetin-Leclercq J : Antimalarial compounds isolated from plants used in traditional medicine. Journal of Pharmacy and Pharmacology 2009, 61:1401–1433. 4. Bero J and Quetin-Leclercq J: Natural products published in 2009 from plants traditionally used to treat malaria. Planta Medica 2011, 77:631-40. 5. Kaur K, Jain M, Kaur T, Jain R: Antimalarials from nature. Bioorganic & Medicinal Chemistry 2009, 17:3229–3256. 6. Nogueira CR and Lopes LMX: Antiplasmodial Natural Products. Molecules 2011, 16:2146-2190 7. Ginsburg H and Deharo E: A call for using natural compounds in the development of new antimalarial treatments – an introduction. Malaria Journal 2011, 10 (suppl. 1):S1 8. Willcox M, Graz B, Falquet J, Diakite C, Giani S, Diallo D: A “reverse pharmacology” approach for developing an antimalarial phytomedicine. Malaria journal 2011, 10(suppl1):S8 9. Jansen, O., Tits, M., Angenot, L., Nicolas, J.-P., De Mol, P., Nikiema, J.-B., & Frédérich, M : Anti-plasmodial activity of Dicoma tomentosa (Asteraceae) and identification of urospermal A-15-O-acetate as the main active compound. Malaria Journal 2012, 11, 289. 10. Tchinda, A. T., Jansen, O., Nyemb, J.-N., Tits, M., Dive, G., Angenot, L., & Frédérich, M. Strychnobaillonine, an unsymmetrical bisindole alkaloid with an unprecedented skeleton from Strychnos icaja roots. Journal of Natural Products 2014, 77(4), 1078–82. 11. Muganga, R., Angenot, L., Tits, M., & Frédérich, M : In vitro and in vivo antiplasmodial activity of three Rwandan medicinal plants and identification of their active compounds. Planta Medica 2013, 80(6), 482-489. [less ▲]

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See detailPRESSÃO PARCIAL (PCO2) E FLUXO DE DIÓXIDO DE CARBONO (CO2) EM AMBIENTES DE VÁRZEA AMAZÔNICOS
Amaral, JHF; Barbosa; Kasper, D et al

Conference (2015, July 12)

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See detailSmall Heat Shock Proteins (sHSPs), specific markers of exercise-induced muscle damage
Hody, Stéphanie ULg; Simonet, Arnaud ULg; Lacrosse, Zoé ULg et al

Poster (2015, July 12)

Unaccustomed eccentric (ECC) exercise may cause exercise-induced muscle damage (EIMD) whereas repeating submaximal ECC sessions is known to prevent this damage. The present study aimed to better ... [more ▼]

Unaccustomed eccentric (ECC) exercise may cause exercise-induced muscle damage (EIMD) whereas repeating submaximal ECC sessions is known to prevent this damage. The present study aimed to better understand the molecular mechanisms underlying EIMD and subsequent adaptation. C57BL adult mice were submitted to different treadmill running protocols: IEE (intense ECC exercise), ET (ECC training), CT (concentric training), LT (level training), ET+IEE, CT+IEE. A 2D-DIGE proteomic analysis on mouse quadriceps muscles revealed that HSP25 and alpha-crystallin B chain were significantly more abundant in IEE, CT+IEE, ET+IEE and ET groups compared to unexercised mice. Interestingly, immunofluorescence analysis highlighted that all damaged fibers also showed positive staining for sHSPs. In contrast, sHSPs+ fibers are not necessarily damaged, suggesting that the sHSPs response precedes increased sarcolemma permeability. Our data demonstrate that ECC exercise specifically increases sHSPs expression which may represent an early marker of damage and/or adaptation of the muscle fibers to ECC contraction. [less ▲]

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See detailCrop supplemental irrigation experiences in Burkina Faso
Zongo, Bétéo ULg; Diarra, Abdoulaye; Barbier, Bruno et al

in Field, Christopher; Jouzel, Jean; Le Treut, Hervé (Eds.) Our ender common climate future change, Abstract Book (2015, July 10)

This study assesses the impact of supplemental irrigation from small man-made basins on cereal production in climate variability and change context marked by dry spells in the Sahelian zone of Burkina ... [more ▼]

This study assesses the impact of supplemental irrigation from small man-made basins on cereal production in climate variability and change context marked by dry spells in the Sahelian zone of Burkina Faso. After two years, the experiments showed that this innovation in family farms increases maize yield and allows growing a second crop with the surplus of water available in the basin. At the end of the 2012-2013 campaign, the average maize yield was estimated 2.5 t/ha on experimental plots (EP) and 1.7 t/ha on control plots (CP). The average yield of the 2013-2014 campaign was evaluated as 3.3 T/ha and 0.9 t/ha for EP and CP respectively. Increase in yield is 0.8 t/ha for the 2012-2013 campaign and 2.4 t/ha during 2013-2014. It appears as well as the yield obtained on EP in 2012-2013 and 2013-2014 for bridging cereal need of 2 and 6 additional persons respectively in agricultural households compared to the CP. The review of the Net present value, Internal rate of return and the Net benefits increase ratio show that the profitability to practice supplemental irrigation depends on the types of basins. [less ▲]

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See detailDeterministic Manufacturing constraints for Optimal Distribution in the Case of Additive Manufacturing
Bauduin, Simon ULg; Collet, Maxime ULg; Duysinx, Pierre ULg et al

Conference (2015, July 09)

An overview of the difficulties of coupling additive manufacturing to topology optimization with various solution founded and implemented.

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See detailAlgorithmic aspects of converting surface mesh data to volumetric images
Plougonven, Erwan ULg; Léonard, Angélique ULg

Conference (2015, July 09)

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data ... [more ▼]

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data, point sets, finite elements, vector fields, implicit surfaces, graphs, basic shapes (spheres, cylinders, or cubes), etc. The work presented here discusses the problem of converting a triangulated surface mesh to a 3D image, a need that arises for example when using active surface-type segmentation methods of 3D images, shape-fitting, or combining data from laser surface scanning with 3D imaging. During the course of numerous projects, two main classes of mesh-to-image conversions have appeared: those identifying voxels (pixels in a 3D image) that intersect the mesh, or voxels that are contained in the mesh, supposing it defines a closed surface. [less ▲]

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See detailA probabilistic multi-scale model for polycrystalline MEMS resonators
Lucas, Vincent ULg; Wu, Ling ULg; Paquay, Stéphane et al

Conference (2015, July 09)

The size of micro-electro-mechanical systems (MEMS) is only one or two orders of magnitude higher than the size of their micro-structure, i.e. their grain size. As a result, the structural properties ... [more ▼]

The size of micro-electro-mechanical systems (MEMS) is only one or two orders of magnitude higher than the size of their micro-structure, i.e. their grain size. As a result, the structural properties exhibit a scatter. As an example we study the beam resonator illustrated in Fig. 1(a), made of poly-silicon material, in which each grain has a random orientation. Solving the problem with a full direct numerical simulation combined to a Monte-Carlo method allows the probability density function to be computed as illustrated in Fig. 1(b). However this methodology is computationally expensive due to the number of degrees of freedom required to study one sample, motivating the development of a non-deterministic 3-scale approach [3]. In a multiscale approach, at each macro-point of the macro-structure, the resolution of a microscale boundary value problem relates the macro-stress tensor to the macro-strain tensor. At the micro-level, the macro-point is viewed as the center of a Representative Volume Element (RVE). The resolution of the micro-scale boundary problem can be performed using finite-element simulations, as in the computational homogenization framework, e.g. [2]. However, to be representative, the micro-volume-element should have a size much bigger than the microstructure size. In the context of the MEMS resonator, this representativity is lost and Statistical Volume Elements (SVE) are considered. These SVEs are generated under the form of a Voronoi tessellation with a random orientation for each silicon grain. Hence, a Monte-Carlo procedure combined with a homogenization technique allows a distribution of the material tensor at the meso-scale to be estimated. The correlation between the meso-scale material tensors of two SVEs separated by a given distance can also be evaluated. A generator at the meso-scale based on the spectral method [4] is implemented. The generator [3] accounts for a lower bound [1] of the meso-scale material tensor in order to ensure the existence of the second-order moment of the Frobenius norm of the generated material tensor inverse [5]. Using the random meso-scale field obtained with the meso-scale generator, which accounts for the spatial correlation, a Monte-Carlo method can be used at the macro-scale to predict the probabilistic behavior of the MEMS resonator. [less ▲]

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See detailSimplified fatigue resistance in mechanical engineering using topology optimization
Collet, Maxime ULg; Bruggi, Matteo; Bauduin, Simon ULg et al

Conference (2015, July 09)

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See detailCitizen Science and Democratic Citizenship
Van Oudheusden, Michiel ULg; Meyer, Morgan

Conference (2015, July 08)

Citizen science (CS) is now widely recognized as a scienti c research practice that engages "nonscientists," such as journalists, artists, hackers, and entrepreneurs. Examples of CS include amateur ... [more ▼]

Citizen science (CS) is now widely recognized as a scienti c research practice that engages "nonscientists," such as journalists, artists, hackers, and entrepreneurs. Examples of CS include amateur astronomy, biohacking, video gaming, and ornithology, among many others. As many of these practices serve public purposes (e.g. educational goals) and emanate within participatory cultures (e.g. the open science movement), CS can be inscribed in a politics of openness, transparency, and inclusion. These politics are potentially reinforced by the policy uptake of CS (e.g. EU White Paper on CS). Yet, despite its growing public significance and potential to render science more inclusive, CS embeds divergent, often conicting, assumptions about the means and ends of science and the role of the citizen/scientist in contemporary democracy. For instance, in its 'purest' form, CS emerges as a reaction against industry and institutional science, in so far as these institutes are seen to inhibit open knowledge sharing. On the other hand, CS sometimes links to commercial endeavors. CS should thus be approached as a multilayered practice that has the power to reshape existing policies, categories, and identities. Taking these reflections into consideration, this panel asks how CS (re)constructs the contemporary citizen, scientist, and citizen scientist. How are citizens transformed into active 'co-creators' of science? Which political rights do citizen scientists claim, as individuals or as groups? Which tools do citizen scientists mobilize to build communities around scientific endeavor? How local or global are the politics of CS? How do policymakers act as facilitators, patrons, or challengers of a more collective, open science? These questions demand critical attention, as CS is performative of democratic citizenship. The panel's questions resonate with the following conference themes: How are publics constructed by policies? To what extent are groups and identities shaped in the policymaking process? How do publics express themselves? [less ▲]

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See detailOpen pits or deep mines used for Underground Pumped Storage Hydroelectricity (UPSH): impacts on groundwater exchanges
Pujades, Estanislao ULg; Willems, Thibault ULg; Orban, Philippe ULg et al

Poster (2015, July 08)

UPSH using abandoned works is an attractive alternative to improve the efficiency of power plants, which cannot regulate the amount of electricity generated according to the demand (wind, solar or nuclear ... [more ▼]

UPSH using abandoned works is an attractive alternative to improve the efficiency of power plants, which cannot regulate the amount of electricity generated according to the demand (wind, solar or nuclear). UPSH plants can store (pumping water from an underground to an upper reservoir) or produce energy (releasing water from an upper to an underground reservoir) during the low or high demand periods. However, it is mandatory to determine 1) the impacts caused on aquifers and 2) the role played by the aquifer characteristics in order to assess the suitability of UPSH plants. Numerical simulations are developed in order to ascertain the groundwater flow impacts and the variables involved in the process. Given the earlier stages of our study, results are obtained considering regular pumping-injection cycles and simplifying the shape of the mine/open pit. The most noticeable effect consists in an oscillation of the groundwater. The hydraulic head around which groundwater oscillates, the magnitude of the oscillations and the time to achieve a pseudo-steady state (magnitude and head reached during oscillations do not vary anymore with time) depend on the boundaries, the parameters of the aquifer and the characteristics of the underground reservoir. [less ▲]

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See detailLa presse vidéoludique française : périodisation et enjeux
Dozo, Björn-Olav ULg

Conference (2015, July 08)

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See detailShewhart Control Charts with Guaranteed In-Control Performance
Faraz, Alireza ULg; Heuchenne, Cédric ULg; Woodall, W.H.

Conference (2015, July 08)

The in-control performance of the Shewhart X ̅ and S2 control charts with estimated in-control parameters has been evaluated by a number of authors. Results indicate an unrealistically large amount of ... [more ▼]

The in-control performance of the Shewhart X ̅ and S2 control charts with estimated in-control parameters has been evaluated by a number of authors. Results indicate an unrealistically large amount of Phase I data is needed to have the desired in-control average run length (ARL) value in Phase II. To overcome this problem, it has been recommended that the control limits be adjusted based on a bootstrap method to guarantee that the in-control ARL is at least a specified value with a certain specified probability. In our paper we present simple formulas for the required control limits so that practitioners do not have to use the bootstrap method. An assumption of normality is required. The advantage of our proposed method is in its simplicity; there is no bootstrapping and the control chart constants do not depend on the Phase I sample data. [less ▲]

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See detailBeyond indiscipline of Labor Market Intermediaries : The Case of Public Employment Services and Private Providers Partnerships
Remy, Céline ULg; Beuker, Laura ULg; Gérard, Julie ULg

Conference (2015, July 08)

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling ... [more ▼]

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling readability needs and modernization of Public Employment Services (PES) have appeared. Meanwhile, a spectacular growth of private employment operators - market and non-market - was recognized by the International Labor Organization in all member states, in order to respond effectively to the increased requests of support and training for the beneficiaries of the PES. In this new context, PES are invited by the European Union (EU) – particularly through its multiple directives – to rethink and reposition their traditional activities of placement, training and support for jobseekers according to a "mixed" management of the labor market. Therefore, PES entrust operation and management of their activities to private providers, as part of a contractual agreement. In this way, these operators provide a "back office function for SPE via a system of delegation governed by a specific division of labor formalized in a partnership agreement between PES and the private provider". Thus, these private labor market intermediaries (LMI’s) as active members on the public orders market work both on their own behalf and on behalf of the public authority. These new collaborations, qualified public-private partnerships (PPPs), allow PES to outsource and delegate a part of their missions they could not achieve internally. So PES combine the role of "actor" and the role of "manager" / "principal" in the labor market. To facilitate the coordination of their activities with the private sector, PES made the decision to create a partnerships service. The officers of this service have the mission to oversee this new form of regulation of the labor market. While collaboration rules are initially determined by the PES, the agents are required to implement them and have the private operators following them. Our interest is to study how these actors – or stakeholder of the PPPs – implement this public action device. Despite differences in both organizational and cultural (for instance bureaucratic rigidity versus informal structure, constraint reporting, management autonomy, etc.), public and private actors work together to serve community and beneficiaries of the PES for their professional integration in the labor market. To analyze how these actors interact and live the partnership relationship, established between agreement and disagreement, we will rely on the economy of conventions and especially on the theoretical contributions of the Theory of justification. In this way, we will identify the different logics of action (present in the merchant, civic, industrial worlds, etc.) that guide the practices of stakeholders, from their discourse and in particular the underlying arguments to justify their actions. Our analysis is rooted in empirical material composed of semi-structured interviews (N=89) and various observations of interactions made within the partnership services and with providers (N=132). These observations focused on three key moments in the life of the partnership: the selection of projects, the monitoring and evaluation of projects by the agents. With this approach, our goal is twofold. On the one hand, we want to highlight the moments when the actors "interpret" the regulatory framework that structure their actions within the partnership relationship. On the other hand, we want to understand the arguments used by actors to justify and legitimize their indiscipline. [less ▲]

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See detailAttitudes toward Gay and Lesbian Marriage and Parenting in Italy
Baiocco, Roberto; D'Amore, Salvatore ULg; Green, Robert-Jay et al

Conference (2015, July 08)

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See detailAttitudes toward Gay and Lesbian Marriage and Parenting Across Seven European Countries
D'Amore, Salvatore ULg; Green, Robert-Jay; Katzuny, Katy et al

Conference (2015, July 08)

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See detailDe "Poétique" à "Points Essais" : (ré)invention du livre ?
Lorent, Fanny ULg

Conference (2015, July 08)

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See detailControlled clinical trial of repeated left prefrontal transcranial direct current stimulation in patients with chronic minimally conscious state
Thibaut, Aurore ULg

Poster (2015, July 08)

Thibaut A., Bruno MA., Wannez S., Donneau AF., Martial C., Chatelle C., Laureys S. Background: A recent study showed that single-session anodal transcranial direct current stimulation (tDCS) applied to ... [more ▼]

Thibaut A., Bruno MA., Wannez S., Donneau AF., Martial C., Chatelle C., Laureys S. Background: A recent study showed that single-session anodal transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal cortex (LDLPF) transiently improves consciousness in 43% of patients in minimally conscious state (MCS) (1). We here test the potential effects and safety of repeated tDCS in severely brain-damaged patients with MCS. Methods: In this double-blind cross-over sham-controlled experimental design, we delivered two sessions of repeated (5 days of stimulation) tDCS, either anodal or sham in a randomized order. We stimulated the LDLPF cortex (Figure 1) during twenty minutes in 20 MCS patients (12 men, aged 48±16 years, time since onset 78±95 months, 12 post-traumatic). Consciousness was assessed by the French adaptation of the Coma Recovery Scale Revised (CRS-R; 2) before and after each stimulation (Figure 2). Results: A treatment effect was observed for the comparison between CRS-R total scores at baseline and after 5 days of real tDCS (p<0.01). Behaviorally, 10/20 patients showed a tDCS- related improvement; 5 patients responded after the first stimulation and 5 other patients responded after 2, 3 or 4 days of stimulation (Figure 3). No side effect (e.g. epilepsy, sign of pain, drowsiness) was reported. Conclusion: Our results demonstrate that repeated (5 days) anodal LDLPF tDCS is safe and might improve signs of consciousness in about half of patients in MCS. It is important to note that the first session is not predictive for a future positive effect of the efficacy of the non-invasive electrical stimulation. References: 1. Thibaut A, Bruno MA, Ledoux D, Demertzi A, Laureys S. tDCS in patients with disorders of consciousness: sham-controlled randomized double-blind study. Neurology. 2014 Apr 1;82(13): p. 1112-8. 2. Schnakers C, Majerus S, Giacino J, Vanhandenhuyse A, Bruno MA, Boly M, Moonen G, Damas P, Lambermont B, Lamy M, Damas F, Ventura M, Laureys S. A French validation study of the Coma Recovery Scale-Revised (CRS-R). Brain Injury. 2008 Sep ;22(10): p. 786-92. [less ▲]

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See detailModelling Uncertainties in Long-Term Predictions of Urban Growth: A Coupled Cellular Automata and Agent-Based Approach
El Saeid Mustafa, Ahmed Mohamed ULg; Saadi, Ismaïl ULg; Cools, Mario ULg et al

in Ferreira, Joseph; Goodspeed, Robert (Eds.) Proceedings of CUPUM 2015 (2015, July 07)

Modelling the growth of urban settlements is of considerable interest for different applications, amongst which integrated flood management. This study aims at modelling urban growth for a long time ... [more ▼]

Modelling the growth of urban settlements is of considerable interest for different applications, amongst which integrated flood management. This study aims at modelling urban growth for a long time horizon up to 2100 and to integrate the model outcomes with a hydrological model for the same time horizon. Forecasting land-use change over such time frames entails very significant uncertainties. In this regard, the main focus of this paper is attributed to the handling of uncertainty in an urban growth model. To this end, we examine a Monte Carlo Simulation method, which is integrated in the proposed urban growth model. Transition probabilities for each non-urban cell are estimated by a coupled Cellular Automata-Agent-Based ap-proach. The results help to handle uncertainty over long time horizons and to assess the increment in degree of uncertainty at every time-step. [less ▲]

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See detailMethane distributions and sea-to-air fluxes in the South China Sea and the West Philippines Sea
Tseng; Chen; Borges, Alberto ULg et al

Poster (2015, July 07)

Detailed reference viewed: 16 (3 ULg)
See detailCO2-sourced non-isocyanate polyurethanes: from the monomer synthesis to the elaboration of polymeric materials
Gennen, Sandro ULg; Grignard, Bruno ULg; Gilbert, Bernard ULg et al

Conference (2015, July 07)

Due to problems related to the rarefaction of fossil resources and the global warming that comes from CO2 emissions, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and ... [more ▼]

Due to problems related to the rarefaction of fossil resources and the global warming that comes from CO2 emissions, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and environmentally friendly must be explored to produce chemicals. Besides the valorization of bio-based raw materials, the use of CO2 as a C1 carbon source into added-value products has gained interest in both academic and industrial fields. One promising way to valorize CO2 relies on its chemical fixation onto epoxides to produce cyclic carbonates that find applications as electrolytes in lithium ion batteries, as aprotic polar solvents or as useful intermediates for polycarbonates. Cyclic carbonates also react with primary amines to produce 2-hydroxyethylurethane. This reaction can be extrapolated to the synthesis of non-isocyanate polyurethanes (NIPU) by polyaddition of bifunctional cyclic carbonates with diamines.5 This study focusses on (i) the synthesis of cyclic carbonates using new highly efficient organocatalysts and (ii) their valorization as monomers to produce non-isocyanate polyurethanes. First, we have identified a bicomponent organocatalyst for the very fast synthesis of cyclic carbonates from CO2 and epoxides under very mild reaction conditions. Kinetics of reactions were followed by online Raman spectroscopy. NMR titrations were realized to evidence the mechanism of activation of this novel organocatalytic system that will be discussed in detail this talk. The second objective relies on the development of new efficient organocatalysts for the synthesis of high molar masses NIPUs in short reaction times. Organic compounds interacting with the cyclic carbonate by hydrogen bonding were identified and their catalytic activity was highlighted by a model reaction between ethylene carbonate and a primary amine before extrapolation to the synthesis of NIPUs that find applications as coatings or foamed materials. [less ▲]

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See detailTreatments for patients with disorders of consciousness
Thibaut, Aurore ULg

Conference (2015, July 07)

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See detailStress constrained topology optimization for additive manufacturing: Specific character and solution aspects
Duysinx, Pierre ULg

Conference (2015, July 07)

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress ... [more ▼]

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress constraints are rather limited (Duysinx & Bendsoe, 1998). More recently the generalized shape optimization approach using level set methods (see for instance Allaire, Jouve, Troader, 2004, Belytchko, Xiao, Parimi, 2003) has followed the tracks of topology optimization and has mainly been focusing on compliance minimization problems. The ‘compliance type’ formulation has produced quite interesting results in many problems because controlling the energy and the displacements under the loads is generally favourable for deflection control and because, for one load case, the compliance minimization leads to a fully stressed design nearly everywhere in the structure. However there are theoretical results that clearly show that the strongest and the stiffest structural layout can be quite different. As demonstrated in Rozvany & Birker (1994) truss topology optimization can lead to different results when there are several load cases, different stress limits in tension and compression, or when there are several materials involved. Therefore, the first goal of the paper points out the importance of considering stress constraints as soon as the preliminary design phase, that is, to include stress constraints in the topology optimization problem. Revisiting some contributions of the authors, this paper aims at illustrating the key role of stress constraints in the framework of topology optimization of continuum structures. The recent developments are able to treat: • Integrated stress criteria (i.e. global) relaxed stress constraints that aggregate the stress constraints in each finite element in order to be able to circumvent the large scale character of the local stress constraints. • Stress criteria that are able to tackle non equal stress limits in tension and compression. The usual von Mises criterion is unable to predict real-life designs when the structure is made of materials with unequal stress limits like concrete or composite materials. These different behaviours in tension and compression result in quite specific designs. Numerical applications make possible to point out the different nature of structural lay out for maximum strength and maximum stiffness. This one is clearly demonstrated in two kinds of particular situations: once several load cases are considered and when unequal stress limits in tension and compression are involved. The second contribution of the paper deals with the solution aspects of large scale constrained optimization problems. Because of the huge number of design variables, dual methods combined with local convex approximations such as CONLIN (Fleury, 1989) or MMA (Svanberg, 1987) are well indicated to solve classical topology optimization methods. However stress constrained problems introduce also a so large number of active constraints that one comes to a rather delicate situation. We show that the optimizer effort increases mostly as the cube of the number of constraints. In order to circumvent the problem, the idea developed in the paper is to combine first or second order approximations (Bruyneel, Duysinx, Fleury, 2002) with zero order approximations of stress constraints, especially for the subset of restrictions that are likely not to be active or not to change too fast. At first the paper presents the way to derive zero-order approximations of -relaxed stress constraints (that is necessary to cope with the singularity phenomenon of stress constraints in topology optimization). Then the proposed hybrid approach mixing approximation of different orders is benchmarked on numerical applications illustrating the reduction of computation time for solving optimization problems without sacrifying to the robustness and efficiency. Numerical applications will investigate topology optimized benchmark examples combined with additive manufacturing fabrication to illustrate the developments. [less ▲]

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