References of "Scientific congresses and symposiums"
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See detailPsychiatrie et liberté : approche phénoménologique
Englebert, Jérôme ULg; Cormann, Grégory ULg

Conference (2016, October 22)

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See detailThe Middle Ages: A New Age for the Reception of the Gods of Egypt
Veymiers, Richard ULg

Conference (2016, October 20)

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See detailQUALITY EVALUATION OF AMOXICILLIN AND COMBINATION OF AMOXICILLIN – POTASSIUM CLAVULANATE AS PART OF INVESTIGATION OF THE OFFICIAL AND PERIPHERAL DRUG MARKET IN KINSHASA, LUMBUBASHI AND KOLWEZI - DRC.
Kalenda Tshilombo, Nicodème ULg; Marini Djang'Eing'A, Roland ULg; Hubert, Philippe ULg et al

Conference (2016, October 18)

Drug substandard and counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of ... [more ▼]

Drug substandard and counterfeiting is a sad and worrisome reality, especially in developing countries where quality control is not effective and sometimes not existing at all despite political will of governments.In this context, we have focused our study towards amoxicillin alone and/or combined with potassium clavulanate since it is one the very used medicines in pediatric medications.Two analytical methods were developed based on the USP monograph. Prior to their application in routine, we evaluated the suitability of these methods through validation applying the accuracy profile of total error. The latter were able to allow monitoring the quality of the two active ingredients here above in the 50 samples from Congolese market. They were collected in Kinshasa, Lumbubashi and Kolwezi at official and non official medicines distributors, in peripheral area. The dramatic results obtained confirm that substandard and counterfeit medicines remain a crucial problem on public health in low-income countries [less ▲]

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See detailAnorexie et régulation émotionnelle
Englebert, Jérôme ULg

Conference (2016, October 08)

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See detailQuelques réflexions méthodologiques sur les abandons de sanctuaires en Grèce antique
Palamidis, Alaya ULg

Conference (2016, October 07)

The archeological identification of the abandonment of cults faces two main difficulties. First, the absence of material posterior to a certain date in an excavated sanctuary does not necessarily mean ... [more ▼]

The archeological identification of the abandonment of cults faces two main difficulties. First, the absence of material posterior to a certain date in an excavated sanctuary does not necessarily mean that the sanctuary was abandoned. Secondly, the abandonment of a sanctuary does not necessarily mean the abandonment of the cult, since the cult may have been transferred to another sanctuary. [less ▲]

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See detailShaping (im)mobility: borders, camps, and non-state actors
Da Silva, Amanda Carolina ULg

Conference (2016, October 07)

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See detailQuality Control Laboratories involved in the WHO Prequalification
Marini Djang'Eing'A, Roland ULg

Conference (2016, October)

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See detailOceanBrowser: on-line visualization of gridded ocean data and in situ observations
Barth, Alexander ULg; Watelet, Sylvain ULg; Troupin, Charles et al

Conference (2016, October)

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See detailA review of Silurian dispersed spore assemblages from the Arabian Plate: biostratigraphy and palaeogeography
Wellman, CH; Steemans, Philippe ULg; Breuer, P et al

Conference (2016, October)

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See detailUn chantier de modernisation des contextes de travail: le "New Way of Working" dans une compagnie d'assurances
Jemine, Grégory ULg

Conference (2016, October)

Dans les réflexions récentes portant sur l’organisation du travail en entreprise, nombreux sont les auteurs qui s’intéressent à la question des « nouvelles formes d’organisation ». Sous cette appellation ... [more ▼]

Dans les réflexions récentes portant sur l’organisation du travail en entreprise, nombreux sont les auteurs qui s’intéressent à la question des « nouvelles formes d’organisation ». Sous cette appellation se rassemblent des courants aux dénominations différentes (entreprise libérée, entreprise virtuelle, « holacracie »…) partageant cependant des principes fondateurs communs (tels que la flexibilité, l’autonomie du collaborateur ou encore la digitalisation des pratiques de travail). A travers une étude de trois mois au sein d’un département de protection juridique d’une importante compagnie d’assurances située à Bruxelles, nous étudions un projet de changement basé sur le « New Way of Working » (NWoW) – un chantier managérial se développant principalement aux Pays-Bas et en Belgique depuis une dizaine d’années, proposant une « nouvelle » vision des travailleurs dans le secteur tertiaire. Nous rendons compte des trois composantes clés du projet NWoW telles qu'il est problématisé dans notre étude de cas: les Bricks (travail en open-space, bureaux flexibles, travail à distance), les Bytes (nouveaux outils numériques, travail sans papier, connectivité) et les Behaviors (autonomie et responsabilité des collaborateurs, passage du contrôle à la confiance). Nous concluons par une réflexion structurée autour des "4C": dans ces nouveaux environnements de travail, de nouvelles questions émergent en termes de confiance, de contrôle, de cohésion et de coordination. [less ▲]

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See detailTransition to parenthood of lesbian parents: key processes and clinical implications
Scali, Thérèse ULg; D'Amore, Salvatore ULg; Haxhe, Stéphanie ULg et al

Conference (2016, September 29)

The transition to parenthood is a key process for understanding the development of family relationships in a systemic perspective. This process has been studied mostly in heterosexual families but very ... [more ▼]

The transition to parenthood is a key process for understanding the development of family relationships in a systemic perspective. This process has been studied mostly in heterosexual families but very few studies focus on families with same-sex families. This exploratory study analyzes the key passages of the transition from 17 lesbian headed families through a quantitative analysis of socio-demographic data, information about the coming-out, pair formation, project of the child, the child's arrival, as well as social and cultural pressures towards family and stressors. The main results show that the decision making to become parents is generally harmonious (70%) between the members of the couple, and only a few had substantial conflicts (17,1%). Moreover, the motivation to become parents seems to be stronger for the mother who carried the child (57, 1%)than for the social mother. The majority of the lesbian mothers reported no medical homophobia (64,3%) Regarding the caregiving tasks, they seem to be equally shared between social and biological mothers. In regards to the child, almost 70% are aware of their parents’ sexual orientation (as only 5.7% are not fully aware). Finally, no changes in the quality of relationship with the family of origin have been found after the birth of the baby. Clinical implications of these results will be discussed. [less ▲]

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See detailGenomics and ecological adaptation: metal hyperaccumulation in Arabidopsis halleri
Hanikenne, Marc ULg

Conference (2016, September 27)

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See detailComparison of temperature from DTS and ERT with direct measurements during heat tracer experiments in heterogeneous aquifers
Nguyen, Frédéric ULg; Hermans, Thomas ULg; Jamin, Pierre ULg et al

Conference (2016, September 27)

Geothermal field characterization and heat tracer experiments often rely on scarce temperature data collected in boreholes. Electrical resistivity tomography (ERT) and distributed temperature sensing (DTS ... [more ▼]

Geothermal field characterization and heat tracer experiments often rely on scarce temperature data collected in boreholes. Electrical resistivity tomography (ERT) and distributed temperature sensing (DTS) have the potential to provide spatial information on temperature changes in the subsurface. In this contribution, we show how DTS and ERT have been used to investigate the heterogeneity of a heterogeneous aquifer during a heat tracing experiment under forced gradient conditions. Optic fibers were installed in the heat injection well and in two piezometers intersecting the main flow directions at 8 m from the injection well. These piezometers were also equipped with ERT. The DTS measurement in the injection well clearly shows the two-layer nature of the aquifer. After the end of injection, the temperature in the bottom part of the well decreases faster than in the upper part due to the higher water fluxes. Those results are confirmed by DTS measurements in natural flow conditions during a heating wire test. DTS and ERT in the cross-panel both show the vertical and lateral heterogeneity of the aquifer. Temperatures only increase significantly in the bottom part of the aquifer where advection is predominant. However, strong differences are observed laterally. ERT additionally shows that the hot plume is divided in two main flow paths, which is confirmed by direct temperature measurements. The comparison of DTS and ERT shows that one of the well is suffering from water mixing. Indeed, temperature from DTS are homogeneous over the whole tichkness of the aquifer, whereas ERT temperature, less affected by local variations, are varying. Our study demonstrate the value of spatially distributed measurements for the monitoring of heat tracer experiment and highligths the issue of multilevel sampling. The detailed temperature measurements can be subsequently used in hydrogeological model to better estimates heat flow and transport parameters. [less ▲]

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See detailQuelles réponses face à la fatigue vocale? Variabilité inter-individuelle des modifications acoustiques de la voix au cours de la journée
Remacle, Angélique ULg; Gerber, Silvain; Garnier, Maëva

Poster (2016, September 26)

Objectifs: 1) décrire l’évolution de 4 indicateurs acoustiques de la fatigue vocale au cours d’une journée de travail et examiner leur universalité dans l'échantillon, 2) déterminer si différentes ... [more ▼]

Objectifs: 1) décrire l’évolution de 4 indicateurs acoustiques de la fatigue vocale au cours d’une journée de travail et examiner leur universalité dans l'échantillon, 2) déterminer si différentes typologies de réponse à la fatigue vocale peuvent être distinguées. Population: 22 enseignantes enregistrées le matin et le soir après leur journée de travail, à 3 temps de l’année: octobre, décembre, et février. Tâche: voyelle [a] tenue produite 5 fois à intensité et fréquence confortables. Paramètres mesurés avec Praat et moyennés sur les 5 répétitions: F0 (Hz), rapport harmoniques/bruit (HNR, dB), local Jitter (%), et local Shimmer (%). Les variations des moyennes entre le soir et le matin (Δ) sont calculées pour chaque paramètre. Résultats: En accord avec la littérature, le Δ moyen pour les 22 participantes aux 3 temps montre une augmentation de F0 et HNR, et une diminution de Jitter et Shimmer au cours de la journée. Cependant, ces résultats ne sont pas généralisés dans notre échantillon. Une analyse hiérarchique ascendante permet d'identifier 3 typologies de réponse à la fatigue vocale, observées suite à la journée de travail. Typologie 1: tendance inverse à la littérature (ΔF0 et ΔHNR négatifs, Δjitter et Δshimmer positifs). Comportement hypofonctionnel en réponse à la fatigue vocale. Typologie 2: tendance et amplitude similaires à la littérature (ΔF0 et ΔHNR positifs, Δjitter et Δshimmer négatifs). Réponse attendue, adaptation saine à la fatigue vocale. Typologie 3: tendance similaire à la littérature mais d’amplitude très marquée. Comportement hyperfonctionnel, suspicion d’un trouble vocal. [less ▲]

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See detailRelectures de La Misère du monde: Bourdieu, Sartre, Enzensberger
Cormann, Grégory ULg

Conference (2016, September 26)

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See detailApplications des relevés 3D au patrimoine, de l'acquisition au système d'information 3D
Hallot, Pierre ULg; Billen, Roland ULg; Poux, Florent ULg et al

Conference (2016, September 23)

Les techniques permettant l’acquisition 3D du patrimoine bâti sont maintenant assez mures et démocratiques pour être utilisées à grande échelle. De plus en plus d’édifices font l’objet d’une sauvegarde ... [more ▼]

Les techniques permettant l’acquisition 3D du patrimoine bâti sont maintenant assez mures et démocratiques pour être utilisées à grande échelle. De plus en plus d’édifices font l’objet d’une sauvegarde numérique sous la forme de nuages de points colorés. Il reste néanmoins de nombreux défis à relever notamment pour : harmoniser les pratiques d’acquisition en terme de qualité et de précision, assurer l’interopérabilité entre les jeux de données ; exploiter pleinement l’information ponctuelle collectée ; et proposer une visualisation adéquate de ces grands jeux de données. Dans le cadre des développements réalisés à l’Unité de Géomatique de l’ULg, nous travaillons à la mise au point de systèmes d’informations permettant d’assurer un lien entre les informations sémantiques issues des applications archéologiques, architecturales, d’histoire de l’art avec les modèles 3D réalisés. La mise en place de ces systèmes d’informations passe par plusieurs étapes de recherche relatives à la sectorisation automatique, les structures de données, la définitions d’ontologies thématiques et finalement les règles sémiologiques de représentations dans un environnement virtuel 3D. Au cours de cette présentation, nous proposons de parcourir trois projets de recherche en cours au sein de l’Unité afin l’illustrer nos propos. Nous présenterons plus particulièrement le cas de la cathédrale Saint-Paul de Liège. [less ▲]

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See detailInfluence d'un programme de revalidation multidisciplinaire post-cancer du sein sur la fonction physique
Leclerc, Anne-France ULg; Foidart-Dessalle, Marguerite ULg; BURY, Thierry ULg et al

in 9ème Congrès commun SFMES - SFTS : Abstract book (2016, September 22)

Objectif : Le cancer du sein ainsi que ses traitements sont à l'origine de nombreux effets secondaires indésirables, notamment sur la fonction physique. Cette étude a pour objectif de déterminer les ... [more ▼]

Objectif : Le cancer du sein ainsi que ses traitements sont à l'origine de nombreux effets secondaires indésirables, notamment sur la fonction physique. Cette étude a pour objectif de déterminer les bénéfices éventuels d’un programme de revalidation multidisciplinaire sur la santé physique des femmes ayant été traitées pour un cancer du sein et d'évaluer l'influence de certaines caractéristiques individuelles initiales sur la réponse du groupe expérimental au programme de revalidation. Matériel et méthodes : L'étude constitue un essai clinique contrôlé non-randomisé évaluant une population totale de 209 patientes, recrutées sur base du volontariat et réparties en deux groupes, soit un groupe contrôle (n = 106) et un groupe expérimental (n = 103). Ce dernier a bénéficié d’une revalidation de trois mois comprenant un entraînement physique supervisé à raison de trois séances par semaine et diverses sessions psycho-éducatives. Pour l'ensemble des participantes, des évaluations constituées d'une part de mesures physiques et fonctionnelles et d'autre part de mesures de composition corporelle ont été programmées à 0 et 3 mois. Celles-ci ont inclus un test de souplesse ("Sit and Reach"), un test d'effort maximal sur bicyclette ergométrique avec suivi cardio-respiratoire, un test de marche de six minutes et la mesure de l'indice de masse corporelle et du pourcentage de graisse corporelle. Afin d'affiner l'analyse, trois groupes ont également été constitués au sein du groupe expérimental à partir des caractéristiques individuelles de thérapie adjuvante (présence de chimiothérapie ou non), de chirurgie (mastectomie ou tumorectomie) et de délai de fin de traitement (délai ≤ 4 mois ou ≥ 8 mois). Résultats : Initialement, toutes les patientes présentent un état de déconditionnement physique, non influencé par le délai de fin de traitement ou par le type de chirurgie, mais bien influencé par la présence d'une chimiothérapie puisque la VO2max apparaît significativement plus faible dans ce cas. Au terme des trois mois, la souplesse (p < 0,0001), la consommation maximale d'oxygène (p < 0,0001), la puissance maximale aérobie (p < 0,0001) et la distance de marche en six minutes (p < 0,0001) s’améliorent significativement au sein du groupe expérimental. Au sein du groupe contrôle, aucune amélioration n'est constatée, excepté pour la distance de marche (p = 0,0031). Par ailleurs, une augmentation significative de l'indice de masse corporelle (p = 0,034) et du pourcentage de graisse corporelle (p = 0,034) est observée au sein du groupe contrôle alors que ce paramètre diminue significativement au sein du groupe expérimental (p = 0,037). Enfin, toutes les patientes du groupe expérimental présentent un même profil de progression quelles que soient leurs caractéristiques individuelles initiales. Conclusion : Cette étude démontre ainsi les effets bénéfiques, tant sur le plan physique que de la composition corporelle, d’une prise en charge multidisciplinaire chez des femmes ayant été traitées pour le cancer du sein. [less ▲]

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See detailDie Familie von Medem. Zur Verbindung von Bildung, Literatur und Politik in Kurland
Leyh, Valérie ULg

Conference (2016, September 21)

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See detailCompetition of phonon and magnon effects in the temperature dependence of spinwave stiffness
Ostler, Thomas ULg; Verstraete, Matthieu ULg; Di Gennaro, Marco ULg et al

Conference (2016, September 21)

Magnons are the elementary magnetic excitations in ordered solids. Understanding such collective excitations is important for a number of technologically relevant fields, such as, magnonics [1] or spin ... [more ▼]

Magnons are the elementary magnetic excitations in ordered solids. Understanding such collective excitations is important for a number of technologically relevant fields, such as, magnonics [1] or spin caloritronics [2]. The central interactions in spin caloritronics are the couplings of phonons with electrons and spin degrees of freedom. Furthermore, understanding the effects of temperature on the phonon and spin degrees of freedom adds a further complexity. In the present work we have developed a multiscale model of ferromagnetic materials and demonstrate the effect of temperature dependent phonon displacements on the magnons spectra. Our results show that the for Fe and Ni the effect of phonon displacements acts to reduce the Curie temperature, whereas for Permalloy the opposite is true due to an increased long-ranged exchange interaction. This increased exchange interaction results in an increasing spin-wave stiffness with increasing temperature, overcoming the usual decrease due to magnon softening. To determine the effects of increasing the phonon temperature we have developed a multiscale model whereby we begin by calculating the thermal displacement of phonons, $\sqrt{\langle u^2(T) \rangle}$, calculated using the phonopy software package [3] using electronic ground state and phonon properties determined using the ABINIT software package [4]. Then the exchange constants are determined using the SPRKKR package [5]. Finally, we use linear spin wave theory to determine the effect of the phonon temperature on the exchange alone, demonstrating an increasing frequency of the acoustic magnon branch. We take into account the thermal effects of the magnetic system through the use of the atomistic spin dynamics approach. Magnon softening due to thermal effects demonstrates a more modest increase in the exchange stiffness (over the purely phononic effect), however, an overall increase is still observed. \newline \newline [1] A. V. Chumak, V. I. Vasyuchka, A. A. Serga, and B. Hillebrands, Nature Physics, {\bf 11}, 453–461 (2015). \newline [2] G. E. W. Bauer, E. Saitoh, and B. J. van Wees, Nature Materials {\bf 11}, 391 (2012). \newline [3] Atsushi Togo and Isao Tanaka, Scr. Mater., {\bf 108}, 1-5 (2015) \newline [4] X. Gonze \textit{et al.} Computer Physics Communications {\bf 180}, 2582-2615 (2009). \newline [5] T. Huhne \textit{at al.} Physical Review B, {\bf 58}, 10236 (1998). [less ▲]

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See detailStudy on contribution of lipids towards the mechanical properties of milk fat globule membrane monolayer
Malik, Priyanka ULg; Danthine, Sabine ULg; Blecker, Christophe ULg

Conference (2016, September 20)

Milk fat globule membrane (MFGM) stabilizes fat globule in milk in form of emulsion. The primary monolayer of MFGM is rich in proteins and secondary bilayer is rich in polar lipids. MFGM finds application ... [more ▼]

Milk fat globule membrane (MFGM) stabilizes fat globule in milk in form of emulsion. The primary monolayer of MFGM is rich in proteins and secondary bilayer is rich in polar lipids. MFGM finds application as an additive in dairy and food industry (e.g. emulsions, infant formulas & reduced-fat products) for its emulsifying and stabilizing properties. MFGM received much attention in recent years due to both its health- beneficial & technological functionalities. This work has been carried out with the objective to understand contribution of various components towards the surface properties of complete MFGM. MFGM was isolated from fresh raw cream. During isolation of MFGM apart from polar lipids and MFGM proteins, neutral lipids are also isolated which have their origin in fat globules but are often considered as a constituent of MFGM. The MFGM was further fractioned into lipid fraction, defatted fraction and polar lipids. The mechanical properties of monolayer were studied for the above fractions using Langmuir film balance. Study of surface properties can also be linked to their techno-functional properties by calculating film elasticity of the compression isotherm which can be linked to emulsifying and stabilizing properties. The analysis of compression isotherms revealed that film elasticity is highly influenced by polar lipids. The behaviour of the MFGM appeared to be influenced by neutral lipid and defatted fraction during beginning of compression and by polar lipids at the end of compression. [less ▲]

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See detailValorization of Seeds from Some Field Border Flowering Seeds
Paul, Aman ULg; Danthine, Sabine ULg; Mutwale Kapepula, Paulin ULg et al

Poster (2016, September 20)

Flowering strips are now being increasingly cultivated along the fields to improve biodiversity. However after serving for the desired function, these plants have no utilization besides animal feed. It ... [more ▼]

Flowering strips are now being increasingly cultivated along the fields to improve biodiversity. However after serving for the desired function, these plants have no utilization besides animal feed. It could be really interesting to valorize some commonly grown plant in these strips to render food or health promoting compounds. With this objective in mind the seeds of Achillea millefolium, Anthriscus sylvestris and Prunella vulgaris were investigated for lipids, proteins and phenolic content. Further the lipids were analyzed for fatty acid profile using gas chromatography and the phenolic compounds in the methanolic extract of defatted seeds were identified using HPLC-DAD. The antiradical activity of the methanolic extracts obtained from defatted seeds was investigated using DPPH and ABTS assays. The anti-inflammatory potential of these seed extracts was evaluated on the reactive oxygen species (ROS) production by stimulated neutrophils and on the specific activity of myeloperoxidase (MPO), a pro-oxidant enzyme marker of inflammation. Seeds from all three plants were analyzed with interesting levels of lipids, proteins and phenolic content. Linoleic acid, oleic acid and alpha-linolenic acid were the major fatty acids analyzed in A. millefolium, A. sylvestris and P. vulgaris respectively. On the other hand different phenolic acid formed the major phenolic constituents. Seed extracts displayed high ABTS and DPPH radical-scavenging activities in a dose dependent manner. Also a strong dose dependent anti-inflammatory activity of all three extracts was observed against ROS production by neutrophils and MPO activity. Results indicate that these seed show a great potential to render lipids which could be utilized as human food, further the defatted seeds could be directly included in human diet due to interesting levels of proteins and anti-inflammation ability. [less ▲]

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See detailRelationships between mind-wandering, personal goals processing, and future thinking.
Stawarczyk, David ULg; D'Argembeau, Arnaud ULg

Conference (2016, September 20)

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the immediate environment and unrelated to the task currently being carried out. Although this ... [more ▼]

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the immediate environment and unrelated to the task currently being carried out. Although this phenomenon has been the object of increasing interest from the scientific community during le last decade, proportionally few studies have attempted to clearly determine the form, content, and possible functions of this particular kind of cognitions. In this presentation, we will review recent evidence from studies mainly performed in our lab suggesting that most instances of mind-wandering refer to the anticipation and planning of future events and are also closely related to the processing of personal goals. More specifically, we will first discuss the findings from behavioral research that examined the phenomenological features of mind-wandering with the use of experience sampling procedures during laboratory tasks. Results of these studies mainly revealed that most of reported mind-wandering episodes are temporally oriented towards the future and that this ‘prospective bias’ can be increased when participants’ attention had been oriented toward their personal goals prior to performing the tasks. We will next review the results of neuroimaging studies that investigated the neural correlates of mind-wandering and we will more specifically focus on meta-analytic evidences suggesting that the neural correlates of mind-wandering strongly overlap with those associated with episodic future thinking and personal goal processing. Together, these results suggest that mind-wandering may have an important adaptive value and could in particular play a key role in planning and preparing for upcoming events related to the individuals’ personal goals. [less ▲]

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See detailImpact du nombre d’alternatives lors d’une tâche de reconnaissance à choix-forcé sur les processus de reconnaissance dans le vieillissement normal
Simon, Jessica ULg; Gilsoul, Jessica ULg; Bastin, Christine ULg

Poster (2016, September 19)

Les tâches de reconnaissance à choix forcé sont classiquement utilisées pour évaluer la mémoire de reconnaissance. Cependant, aucune étude n’a spécifiquement investigué l’impact du nombre d’alternatives ... [more ▼]

Les tâches de reconnaissance à choix forcé sont classiquement utilisées pour évaluer la mémoire de reconnaissance. Cependant, aucune étude n’a spécifiquement investigué l’impact du nombre d’alternatives sur les performances mnésiques des participants âgés. Nous voulons déterminer, d’une part, si le nombre d’alternatives proposées - deux ou trois – et d’autre part, si le degré de similarité entre la cible et ses leurres ont un impact sur les stratégies de récupération mises en place au cours de la tâche. Pour ce faire, nous avons recruté 20 participants jeunes et 20 participants âgés. Lors de la tâche de reconnaissance, nous leur avons demandé de choisir, parmi deux ou trois photographies de visages, celui qui a été présenté précédemment. Certains couples cibles-leurres étaient plus similaires que d’autres (partage de 60% de caractéristiques communes, contre 40%). Pour chaque item sélectionné, les participants devaient expliquer ce qui a guidé leur choix. Les premières analyses (ANOVA à mesures répétées 2 (groupes) x 2 (alternatives) x 2 (similarité) sur les deux dernières mesures, p<0,05) montrent que les performances entre les groupes sont équivalentes pour la tâche de reconnaissance à deux alternatives. A l’inverse, nous avons observé que les participants jeunes avaient significativement de meilleures performances que les âgés dans la tâche de reconnaissance à trois alternatives. Les profils mnésiques des participants seront étudiés à la lumière des modèles à deux processus de la reconnaissance. Nous faisons l’hypothèse d’un recours plus fréquent à la recollection chez les jeunes dans la tâche de reconnaissance à trois alternatives (vs deux alternatives), alors que le choix de l’item se ferait chez les âgés, en comparant directement les degrés de familiarité associés à chaque item et en sélectionnant le plus familier (Norman & O’Reilly, 2003). [less ▲]

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See detailOn-farm Evolution of Genetic Diversity of Four Old Varieties of Phaseolus vulgaris L.
Caproni, Leonardo; Raggi, Lorenzo; Klaedtke, Stephanie ULg et al

Poster (2016, September 16)

On-farm evolution of crop genetic diversity has a key role in adaptation of agricultural systems to changes. The aim of this work was to understand how four different old common bean varieties, which ... [more ▼]

On-farm evolution of crop genetic diversity has a key role in adaptation of agricultural systems to changes. The aim of this work was to understand how four different old common bean varieties, which being made of different genotypes can be referred to as populations, evolved on-farm during three years of multiplication (from 2012 to 2014) in two different experimental sites (Brittany and Luxembourg) under organic farming conditions. The four populations (Flageolet Chevrier Vert, Rognon de Coq, Roi des Belges, Saint Esprit à Œil Rouge) were chosen among those grown by two small-scale organic seed farmers while the commercial variety (Calima) was included as control. In 2015 the initial and the evolved populations were grown in a common field and characterized with morpho-phenological traits. In the same year, young leaf tissues were collected from 94 samples per population (total of 470 samples) for DNA extraction and molecular characterization. Genotyping was carried out using 22 SSR loci and fluorescent PCR amplicons analysed on an ABI3130xl sequencer. Molecular data were then used for multivariate analysis, analysis of molecular variance and pair-wise Fst statistics calculation. Genotyping resulted in the production of about 20K data points. A total of 83 different alleles were identified in 16 polymorphic loci ranging from two (BMb293, BM156, BMd-44) to 18 (BMd-43). The first two axis of the Principal Coordinates analysis (PCoA) explained 76,13% of total diversity and clearly distinguished the five groups of populations. Analysis of Molecular Variance (AMOVA) showed that 76, 20 and 4% of total diversity is among populations, individuals and within individuals, respectively. Only for multiplications carried out in Luxemburg significant differentiation between the original populations and final populations were found in two old varieties (Flageolet Chevrier Vert and Rognon de Coq, Fst = 0.117 and 0.143, respectively, P≤0.001). The results showed that in Luxemburg farmer practices and pedo-climatic conditions significantly shaped the diversity of the two populations. This is confirmed by phenotypic observations, as these multiplications also significantly differed (p<0.05) for flowering date for all varieties except 'Roi des Belges'. [less ▲]

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See detailMetabolites from media supplemented with 3’-sialyllactose and fermented by bifidobacteria have an antivirulent effect against intestinal pathogens
Bondue, Pauline ULg

Poster (2016, September 16)

Introduction Complex oligosaccharides from human milk (HMO) promote growth of bifidobacteria such as Bifidobacterium bifidum [1]. Whey, a by-product of dairy-industry, contents complex oligosaccharides ... [more ▼]

Introduction Complex oligosaccharides from human milk (HMO) promote growth of bifidobacteria such as Bifidobacterium bifidum [1]. Whey, a by-product of dairy-industry, contents complex oligosaccharides (BMO) similar to HMO, which are mainly represented in colostrum by 3’-sialyllactose (3’SL) [2]. Bifidobacterium crudilactis, a species of bovine origin, encodes for β galactosidases and α-glucosidases and could therefore be able to metabolise those BMO [3; 4; 5]. In addition, fermentation products from bifidobacteria can produce antivirulent activity against intestinal pathogenic bacteria [6; 7]. This study focused on capacity of bifidobacteria to metabolise BMO, more particularly 3’SL, and on potential antivirulent effect of cell-free spent media (CFSM) against virulence gene expression of pathogenic bacteria. Material and methods B. bifidum BBA1 and B. crudilactis FR/62/B/3 isolated respectively from breastfed children feces and from cow raw milk cheese were grown on media supplemented with BMO or 3’SL, as sole source of carbon. The CFSM were harvested after centrifugation of cells culture, freeze-dried and concentrated 10 fold. Next, their effects were tested against virulence gene expression using ler and hilA promoter activity of luminescent constructs of Escherichia coli 0157:H7 ATCC 43888 and Salmonella Typhimurium SA 941256, respectively. The effect was confirmed on wild type strains of E. coli O157:H7 ATCC 43890 and S. Typhimurium ATCC 14028 using RT-qPCR. Results Both strains were able to grow in presence of whey or 3’SL, but B. crudilactis showed the best growth compared to B. bifidum. The highest cell concentrations were observed with media containing whey (8.9 ± 0.6 log cfu/ml and 8.1 ± 0.3 log cfu/ml, respectively). CFSM from fermented media supplemented with 3’SL resulted in under-expression of hilA and ler genes for the luminescent constructs and in under-expression of ler (ratios of -15.4 and -8.1) and qseA (ratios of -2.1 and -3.1) genes for the wild type strain of E. coli O157:H7. No effect was observed for the wild type strain of S. Typhimurium. Discussion B. crudilactis presented the best growth potential probably because its genome encodes the enzymatic machinery to use BMO (β galactosidases and α-glucosidases) [3; 4; 5]. The positive effect of media supplemented with milk products on growth of probiotics has been demonstrated previously [8]. CFSM obtained from media supplemented with 3’SL down-regulate several virulence genes of E. coli O157:H7 and potentially S. Typhimurium. This effect has been observed previously with CFSM obtained from fermentation of lactic acid bacteria or bifidobacteria, by production of antivirulent metabolites [2; 3]. BMO combined with some bifidobacteria strains of bovine or human origin could therefore be an interesting synbiotic to maintain or restore the intestinal health of young children. These effects observed in vitro will be further investigated regarding the exact nature of the active molecules. References 1. Garrido D. et al. (2013). Microbiology 159: 649-664. 2. Urashima T. et al. (2013). Biosci Biotechnol Biochem 77: 455-466. 3. Sela D. A. (2011). Int J Food Microbiol 149: 58-64. 4. Milani C. et al. (2014). Appl Environ Microbiol 80: 6290-6302. 5. Bondue P. & Delcenserie V. (2015). Korean J Food Sci Anim Resour 35: 1-9. 6. Medellin-Pena M. J. et al. (2007). Appl Environ Microbiol 73: 4259-4267. 7. Bayoumi M. A. & Griffiths M. W. (2012). Int J Food Microbiol 156: 255-263. 8. Champagne C. P. et al. (2014). Can J Microbiol 60: 287-295. [less ▲]

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See detailWhat’s the difference? Results of a functional study of Aterian and Mousterian tools from the site of Ifri n’Ammar (Morocco)
Tomasso, Sonja ULg; Rots, Veerle ULg

Conference (2016, September 16)

Until today, the definition of the North African Mousterian has been based on a systematic comparison with the European Mousterian. Particularly the “Aterian” and its tanged tools have been widely ... [more ▼]

Until today, the definition of the North African Mousterian has been based on a systematic comparison with the European Mousterian. Particularly the “Aterian” and its tanged tools have been widely discussed. Researchers considered the tanged Aterian tools as early indications of the existence of hafting techniques [1]. It is currently not entirely understood how the Aterian relates to the Mousterian in North Africa, whether tanged tools can indeed be linked with hafting, and whether non-tanged tools were also hafted, which could indicate that a variety in hafting techniques existed. The site of Ifri n’Ammar presents an ideal chance to compare Aterian and Mousterian technocomplexes. The rock shelter is located in the eastern Moroccan Rif and has a rich and well preserved stratigraphy where Middle Paleolithic tools are abundantly represented [2]. At Ifri n’Ammar, the Aterian and Mousterian assemblages are inter-stratified, which means that the relationship of these industries cannot simply be explained in terms of chronological succession [2,3]. The density of retouched artefacts differs between the Aterian and the Mousterian levels and tanged tools are present in the denser Aterian levels only. These levels also show a higher overall tool frequency. We present the results of a functional study focusing on the artefacts from the upper levels (“Occupation supérieure”) of Ifri n’Ammar, dated between 83 ± 6 ka and 130 ± 8 ka [3]. The functional study was combined with a specific experimental program designed to address questions raised during the analysis of the archaeological material, with a specific focus on hafting. Diagnostic microscopic wear patterns confirm that the tanged tools were used while hafted. Tanged tools did not prove to be related to hunting activities only, but various tool uses could be identified. They all fit, however, within the context of hunting and animal processing activities. The reuse of hafted armatures for other activities is not evident in the present sample. [less ▲]

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See detailFirst come first served: “priority effect“ benefits Ambrosia artemisiifolia L. more than other ruderal Asteraceae species
Ortmans, William ULg; Mahy, Grégory ULg; Monty, Arnaud ULg

Poster (2016, September 14)

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of ... [more ▼]

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of central and southern France, and northern Italy. Northwards beyond the edge of this range, occurrence of casual population have been described for years, but these populations do not appear to become invasive, and the species does not seem to spread. This situation raises the following question: Has the invaded range reached a limit or will the species continue its invasion northwards? To answer this question, we followed two complementary approaches. First we set up an experimental garden in Belgium, 250 km north to the current invaded range, to see if the local climate allows the completion of the species reproduction cycle. Second, we performed an in situ measurement campaign in 12 population located beyond the edge, within the range but near the margin, and in the center of the invaded range. The aim of this campaign was to test whether the species had reduced plant performance towards range margins. The results showed that the species is able to establish populations with high growth rates in Belgium. Furthermore, the species expressed similar performance across the considered areas, even beyond the current invasion front. No evidence of processes constraining the invasion was found, which suggests a great potential for invasion north to the current invaded range. In this uncertain situation, awareness actions should be considered in the northern countries. [less ▲]

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See detailAssessment of vertical contamination of Cd, Pb and Zn in soils around a former ore smelter in Wallonia, Belgium
Liénard, Amandine ULg; Colinet, Gilles ULg

Conference (2016, September 14)

Examples of sites contaminated by atmospheric fallouts are numerous across former industrial areas, among which the valleys of Sambre and Meuse in Wallonia hosted metal ore treatment factories. We have ... [more ▼]

Examples of sites contaminated by atmospheric fallouts are numerous across former industrial areas, among which the valleys of Sambre and Meuse in Wallonia hosted metal ore treatment factories. We have studied the fate of Cd, Pb and Zn in soils affected by atmospheric deposition in the vicinity of old smelters. The importance of vertical redistribution of contaminants in soils is questioned and the aims of this paper are to i) characterize the vertical distribution of TEs and soil properties along diverse soil profiles, ii) evaluate enrichment or impoverishment of TEs along the profiles to discriminate anthropogenic or geogenic origin of contaminations and iii) evaluate whether soil type or land use influenced the mobility of contaminants in the selected profiles. Concentrations of trace elements (Cd, Co, Cr, Cu, Ni, Pb, and Zn) and major elements (Ca, Mg, K, Fe, Al, and Mn) as well as pHKCl and TOC were measured on 22 profiles located in a 3 km radius of a former ore treatment plant in Wallonia (Belgium). Enrichment factor (EF), vertical impoverishment factor (VIF), and availability ratio (AR) were used as diagnostic tools of contamination and migration of Cd, Pb, and Zn in profiles. Data revealed that soil profiles are significantly contaminated. The ranges of enrichment factors for Cd (17-3570), Pb (1-2883), and Zn (2-309) are very broad with the higher EF in the topsoil of profile. VIFs of subhorizons are rarely above 1. In a few remaining cases with VIF > 1, the main factor explaining is soil type (especially, Colluvic Regosols, Luvisols, and, Cambisols with shale load). Cd, Pb and Zn ARs are strongly correlated with TOC and to a lesser extent with pHKCl. Pb and Zn ARs are influenced by soil type and land use only plays on Zn AR. The Cd availability is independent by these two factors. The contents of trace elements measured in soil profiles are very high especially in topsoil. Until now, the Cd, Pb, and Zn vertical distribution shows a low migration from topsoil up to depth. However, we must not minimize the hazard of a future potential transfer. [less ▲]

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See detailExtremophile plants as source of biopesticides against European damageable plant pathogens
Ben Kaab, Sofiène ULg; Parisi, Olivier ULg; De Clerck, Caroline ULg et al

Poster (2016, September 14)

The use of plant-derived products in postharvest disease management may be a valid alternative to conventional chemical treatments (Pane et al., 2016). Unfavorable environmental conditions (such as salt ... [more ▼]

The use of plant-derived products in postharvest disease management may be a valid alternative to conventional chemical treatments (Pane et al., 2016). Unfavorable environmental conditions (such as salt and drought) increase production and accumulation of reactive oxygen species (ROS). Consequently, extremophile plants have developed adaptive responses including the synthesis of specific bioactive molecules used for medical and nutritional purposes (Ksouri et al., 2012). In that context, the main objective of the present study was the identification of effective plant extracts and essential oils from extremophile plants against the most important plant pathogens in Europe (in term of loss, treatment necessity and/or cost). The study began with the selection of four endemic medicinal species suspected to be antimicrobial due to their wealth of phenolic and terpene compounds, such as flavonoids, phenolic acids, and coumarins (Ksouri et al., 2012). Each of the aerial plant materials was grounded and macerated with solvent (methanol or chloroform) for 24 h. The solvent was then eliminated along rotavapor. The yield of plant extract varied between 1.56 and 6.7%. Kinetics of growth of the 3 pathogens cultivable in liquid medium was determined before testing the impact of plant extracts and essential oils. Methanolic and chloroform plant extracts (EM1, EM2, EC1 and EC2) and essential oils (EO1, EO2) were compared for their antifungal potential. The chemical composition of the essential oils obtained by hydrodistillation from the aerial parts was analyzed by GC/MS. Yield of essential oil varied between 0.7 and 1.2%. Therefore, antifungal activity of plant extracts and essential oils was evaluated using ELISA microplates with a blocked randomized design, as described previously (Parisi et al., 2013). The results obtained showed that EM2 at 7 mg/ml has a very high fungistatic activity against Fusarium culmorum, F. oxysporum and Penicillium italicum. It was characterized with a high amount of polyphenols, flavonoids and condensed tannins. Statistical analysis showed that the efficiency of methanol extracts significantly differed from those of the chloroform extracts. In addition, essential oils significantly reduced spores germination in a dose-dependent manner. Their fungistatic activity reached 100% at 6000 ppm. In conclusion, this work allowed us to open new perspectives on the application of extremophile plant extracts as novel biocontrol strategy against plant pathogens. [less ▲]

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See detailTHERMO-ECONOMIC OPTIMIZATION OF ORGANIC RANKINE CYCLE SYSTEMS FOR WASTE HEAT RECOVERY FROM EXHAUST AND RECIRCULATED GASES OF HEAVY DUTY TRUCKS
Guillaume, Ludovic ULg; Legros, Arnaud; Lemort, Vincent ULg

Conference (2016, September 14)

Waste heat recovery (WHR) ORC is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks (HDT). Nonetheless, the adoption of this ... [more ▼]

Waste heat recovery (WHR) ORC is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks (HDT). Nonetheless, the adoption of this technology in the automotive domain requires specific R&D activities going from the system definition to the on-board integration. This study focuses on the preliminary design phase of ORC systems recovering the heat wasted from two of the sources available on a HDT: the exhaust and recirculated gases. From these heat sources and their combinations, 6 possible architectures are identified. On the other hand, 4 volumetric expansion machine technologies are considered (Scroll, Screw, Piston and Vane Expanders). At the end, 24 topologies are modelled considering only the main components (Pump, Heat exchangers, Expansion machines). A three-step optimization method is proposed to identify the most promising system. First, the most suitable design conditions are identified using a simple model of expansion machine. In a second step, the design phase, using more detailed models for the expansion machines, a thermodynamic and economic optimizations are performed. Finally, in a third step, the output power of the latter system models is maximized in off-design conditions. [less ▲]

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See detailDYNAMIC MODELING OF WASTE HEAT RECOVERY ORGANIC RANKINE CYCLE SYSTEMS IN THE AMESIM PLATFROM
Guillaume, Ludovic ULg; Ameel, Bernd; Criens, Chris et al

Conference (2016, September 14)

ORC waste heat recovery is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks. Because of the transient nature of the heat sources ... [more ▼]

ORC waste heat recovery is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks. Because of the transient nature of the heat sources encountered on a truck, dynamic simulations are an essential part of the design process of ORC systems for truck applications. Dynamic models are useful for component design, control design and transient evaluation of ORC systems. To ease the burden of building numerous dynamic models of different candidate ORCs while the design process is ongoing, a library of generic dynamic models of ORCs is built in this work. These models work in synergy with a steady-state ORC design tool in which is added a function to automatically populate the parameters of the dynamic models. In this work, the dynamic model library and their parameterization process in LMS AMESim are described. The platform is largely used in automotive industry and offers a variety of libraries: Engine, Control, Two-Phase Flow, etc. Finally, the dynamic models are compared against the steady-state models and experimental data. [less ▲]

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See detailOrganocatalytic ring-opening polymerization towards polyphosphoesters
Clément, Benoit; Vanslambrouck, Stépanie; Carion, Stéphan ULg et al

Conference (2016, September 13)

Hydrolytically degradable and biocompatible aliphatic polyesters are widely applied for biomedical applications as implants, scaffolds for tissue engineering and, finally, as nanocarriers for drug ... [more ▼]

Hydrolytically degradable and biocompatible aliphatic polyesters are widely applied for biomedical applications as implants, scaffolds for tissue engineering and, finally, as nanocarriers for drug delivery. Aliphatic phophoesters, known since the pioneering work of S. Penczek in the 70’s, exhibit the same properties of hydrolytic degradability and biocompatibility and are thus more and more studied for biomedical applications as well. In the field of materials, anti-fire properties opens up new perspectives. The difference between polyesters and polyphosphoesters in terms of synthesis and properties will be highlighted. Polyphosphosphoesters are synthesized by step-growth and chain growth polymerization. When these polyphosphoesters are synthesized by ring-opening polymerization of cyclic phosphoesters, organocatalysts turned out to be very efficient compared to coodination processes. The last part of the talk will deal with te implementation of ROP of cyclic phosphates towards a series of amphiphilic PEO-block-polyphosphate copolymers of tailored hydrophobicity depending on the length of the lateral alkyl group. These polymers are able to self assemble into nanoparticles by direct dissolution in water, thus in the absernce of any organic solvent. The so-obtained micelles were studied by a set of techniques (Pyrene Fluorescence, Dynamic Light Scattering, Tensiometry). Finally, the influence of the hydrophobicity of the polyphosphate block of the micelle on the encapsulation and the release of a model drug was investigated. [less ▲]

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See detailInvestigating the effect of plant-derived amendments on PAHs degradation in brownfield contaminated soils
Davin, Marie ULg; Starren, Amandine ULg; Colinet, Gilles ULg et al

Conference (2016, September 13)

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistant organic compounds of major concern that tend to accumulate in the environment, damaging ecosystems and health. Brownfields represent an ... [more ▼]

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistant organic compounds of major concern that tend to accumulate in the environment, damaging ecosystems and health. Brownfields represent an important tank for PAHs that require remediation. As an alternative to environmentally aggressive, expensive and often disruptive soil remediation strategies, experiences have been carried on to understand and develop techniques based on bioremediation and phytoremediation. PAHs degradation experiments were conducted in microcosms (laboratory scale) in order to determine whether several plant-derived amendments could enhance bioremediation. Briefly, samples of aged contaminated soils were treated with different concentrations of Medicago sativa or Trifolium pratense root exudates or dried roots, commercial saponin, a natural surfactant found in some plant roots such as some Fabaceae, and some samples were left unamended as controls. Soil samples were incubated for two and four weeks at controlled temperature (28°C). Carbon dioxide emission was monitored throughout the whole incubation. At the end of each experiment, dehydrogenase activity was measured as an indicator of microbiological activity and residual PAHs were determined using High-Performance Liquid Chromatography with Fluorimetric Detection (HPLC-FLD). In total, eleven amendment modalities and two incubation periods were tested and repeated four times. Preliminary experiments show promising results as amended samples seem to show different respiration activities. Ongoing studies will allow discussion as to whether or not PAHs degradation is influenced by the different modalities and if there are any differences according to the nature and concentration of the amendment. [less ▲]

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See detailOrganocobalt complexes as source of radicals for the controlled polymerization of unconjugated monomers
Demarteau, Jérémy ULg; Cordella, Daniela ULg; Kermagoret, Anthony et al

Poster (2016, September 12)

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See detailSynthesis and characterizations of non-isocyanate polyurethane (NIPU) hydrogels
Gennen, Sandro ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

Poster (2016, September 12)

Polyurethane (PU) is on of the most used polymers for the preparation of hydrogels due to its good biocompatibility, biodegradation and excellent mechanical properties. PU hydrogels are found in lot of ... [more ▼]

Polyurethane (PU) is on of the most used polymers for the preparation of hydrogels due to its good biocompatibility, biodegradation and excellent mechanical properties. PU hydrogels are found in lot of applications such as wound dressing, soft contact lenses, drug delivery and scaffolds for tissue engineering. Classicaly, PU is produced by a step-growth polymerization between diols and diisocyanates. However, in order to avoid the use of harmful isocyanates compounds and because of regulations which tend to ban the use of isocyanates, we developed hydrogels based on a non-isocyanate polyurethane (NIPU) chemistry by valorizing CO2-sourced cyclic carbonates and amines. Precisely, NIPU hydrogels were prepared by a solvent-free copolymerization between bifunctional hydrophilic polyethylene glycol cyclic carbonates and diamines in presence of a triamine as a crosslinker, followed by a water swelling of the obtained cross-linked gel. Parameters such as the cross-linking ratio and diamine’s nature were optimized. Different clay contents (cloiste 30B) as nanofiller were dispersed in the ideal cyclic carbonate/diamine/triamine formulation prior polymerization in order to reinforce the compression properties of NIPU hydrogels. Finaly, we were able to prepare NIPU hydrogels with water content up to 80 % and good compression properties using low clay content. [less ▲]

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See detailPAI Annual Meeting
Ouhib, Farid ULg; Aqil, Abdelhafid ULg; Dirani, Ali et al

Poster (2016, September 12)

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See detailPolyphosphoester containing amphiphilic block copolymers as drug nanocarriers
Ergül, Zeynep ULg; Vanslambrouck, Stéphanie; Thiry, Justine ULg et al

Poster (2016, September 12)

The design of drug delivery systems often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, supramolecularly self-assembled ... [more ▼]

The design of drug delivery systems often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, supramolecularly self-assembled amphiphilic block copolymers into spherical micelles are appropriate carriers for poorly soluble drugs. In that framework, we have designed novel functional poly(ethylene oxide)-b-polyphosphoester amphiphilic block copolymers able to cross-linked under UV and degrade in response to a reduction of the pH from neutral conditions. Therefore, an unsaturated alkene side-chain was introduced on the cyclic phosphate monomer according to a one-step reaction followed by its organocatalyzed polymerization initiated by a poly(ethylene oxide) macroinitiator. After self-assembly into water, the micelles were cross-linked by UV irradiation. Then, these cross-linked micelles have been loaded by doxorubicin, i.e. a drug used in cancer therapy. We observed that the doxorubicin loading increased with the number of double bonds on the polyphosphate block of non-cross-linked micelles. This diblock amphiphilic copolymer bearing pendant unsaturations appears thus particularly promising candidate to build micellar drug delivery systems for intravenous injection. [less ▲]

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See detailInfluence of grain boundaries on the COads monolayer oxidation and oxygen reduction reaction kinetics
Asset, Tristan ULg; Chattot, Raphaël; Nelayah, Jaysen et al

Conference (2016, September 12)

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See detailOverhanging Constraints in Addivitive Manufacturing Using Two Different Tools
Bauduin, Simon ULg; Collet, Maxime ULg; Duysinx, Pierre ULg

Conference (2016, September 12)

Topology optimization is widely used as a design tool for advanced application in mechanical, aerospace and automotive industries. This technique offers an optimal distribution of a predetermined amount ... [more ▼]

Topology optimization is widely used as a design tool for advanced application in mechanical, aerospace and automotive industries. This technique offers an optimal distribution of a predetermined amount of material in a given design space. In the last years, a lot of efforts has been invested into the development of high performance methods such as homogenization, SIMP or BESO. However as the state of the art in manufacturing experiences evolution, a coupling between topology optimization and additive manufacturing is needed. Additive manufacturing has numerous advantages that fits the characteristics of topology optimized designs. It can manufacture highly complex design without high cost increase and furthermore continuous density material of the SIMP method could be manufactured by lattice structures. With all the opportunities given by the additive manufacturing the urge to bind the last one to topology optimization is heavily required. Specific constraints related to manufacturing issues have to be taken into account such as the need of supports structures to ensure a good heat evacuation during the manufacturing process, as well as to hold up overhanging section. Some researches have been done to try to include this constraint in the optimization problem such as Leary and al or Andrew T. Gaynor. However this work focuses on 2 different methods (projection scheme and mechanical approach) to tackle the overhanging problem and compare them . [less ▲]

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See detailGeometallurgical Modelling of Low-Grade Itabirite Iron Ores from the Iron Quadrangle, Brazil
Martino, Rémi ULg; Correa de Araujo, Armando; Gotelip Barbosa, Marcela et al

in Proceedings of the XXVIII International Mineral Processing Congress (IMPC 2016) (2016, September 11)

The Iron Quadrangle district is a world-class iron ore mining district in the region of Belo Horizonte, capital of Minas Gerais state, in Brazil. Many mining companies have been mining high-grade hematite ... [more ▼]

The Iron Quadrangle district is a world-class iron ore mining district in the region of Belo Horizonte, capital of Minas Gerais state, in Brazil. Many mining companies have been mining high-grade hematite ores for decades throughout the region. The mines reserves often include itabirite ores which are available in high volumes, but have lower iron grades than hematite ores and require elaborated mineral processing to meet the requirements of downstream steelmaking. Itabirite ores have acquired importance, with the depletion of high-grade hematite reserves due to their intensive mining. The objective of this paper is to propose a geometallurgical model for the processing of itabirite ores from an Iron Quadrangle deposit, which will allow predicting the behaviour of ores throughout the deposit, according to their local variations. An initial step consists in characterizing representative samples of the different ores to acquire mineralogical and textural data. Then, itabirite ores of known characteristics are processed with different techniques, in order to extract the trends and key parameters upon which the geometallurgical model is developed. At first, the model takes into account the particle size distribution and its shift during mining and screening, as well as the chemistry and mineralogy of the material. Then, using the previously identified key parameters such as iron recovery, the model predicts the composition of the processing products. Finally, this data is used to model the mineralogy and mass recovery of the products. The geometallurgical model is of great importance, as it is able to model the processing of any sampled ore throughout the deposit. The incorporation of the results in a mining block model will assist mine planning and opens new opportunities for an optimized mining schedule. [less ▲]

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See detailA new toolbox for the identification of diagonal Volterra kernels allowing the emulation of nonlinear audio devices
Schmitz, Thomas ULg; Embrechts, Jean-Jacques ULg

in Schmitz, Thomas (Ed.) International Congress on Acoustics : ICA, Argentine 5-9 Septembre 2016 (2016, September 10)

Numerous audio systems are nonlinear. It is thus of great importance to study them and understand how they work. Volterra series model and its subclass (cascade Hammerstein-Wiener model) are usual ways to ... [more ▼]

Numerous audio systems are nonlinear. It is thus of great importance to study them and understand how they work. Volterra series model and its subclass (cascade Hammerstein-Wiener model) are usual ways to modelize nonlinear systems. However the identification methods of these models are still considered as an open topic. Therefore we have developed a new optimized identification tool ready for use and presented as a Matlab toolbox. This toolbox provides the parameters of the optimized sine sweep needed for the identification method, it is able to calculate the parameters of the Hammerstein model and to emulate the output signal of a nonlinear device for a given input signal. To evaluate the toolbox, we modelize a guitar distortion effect (the Tubescreamer) having a total harmonic distortion (THD) comprised in the range 10-23\%. We report a mean error of less than 0.7\% between the emulated signal and the signal coming from the distortion effect. [less ▲]

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See detailLinkages and production and marketing of rice vermicelli in traditional craft villages of Bac Giang province
Le Thy Long, Vy; Nguyen Huu, Nhuan; Lebailly, Philippe ULg

Conference (2016, September 10)

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See detailThe Assumptions Underlying Identity in Entrepreneurship Research: A Systematic Review in Leading Academic Journals
Aouni, Zineb ULg; Artemis, Chang; Biga-diambeidou, mahamadou

in The Conference Proceedings from the 2016 British Academy of Management Conference (2016, September 09)

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See detailImplications de la perspective en première personne en psychopathologie : le cas de la schizophrénie
Englebert, Jérôme ULg; Valentiny, Caroline

Conference (2016, September 09)

Les approches traditionnelles de la schizophrénie en psychiatrie se centrent essentiellement sur une perspective que l’on peut qualifier de perspective en « troisième personne ». Ces considérations ... [more ▼]

Les approches traditionnelles de la schizophrénie en psychiatrie se centrent essentiellement sur une perspective que l’on peut qualifier de perspective en « troisième personne ». Ces considérations tentent, de l’extérieur, de circonscrire les difficultés auxquelles sont confrontées les personnes affectées d’une psychopathologie. Dans le cas de la schizophrénie, les manuels insistent notamment sur les symptômes délirants et hallucinatoires – signes sur lesquels, de facto, le clinicien et le patient ne peuvent s’entendre et rencontrer une phénoménologie commune. Une autre voie d’approche, s’inscrivant dans la tradition phénoménologique, propose d’explorer les phénomènes à partir du discours et du vécu subjectif des patients – dans une perspective en « première personne ». À partir d’une recherche récemment menée, nous explorerons le vécu subjectif de six patients schizophrènes à l’aide de l’échelle EASE (Examination of Anomalous Self-Experience). Cette échelle pose des balises dans la co-construction d’une narrativité permettant l’investigation d’expériences liées aux troubles du soi. Ce choix méthodologique s’ancre dans une volonté de laisser la place à l’étonnement, de ne pas pré-penser, ou le moins possible, le recueil d’expériences. Les analyses des phénomènes décrits par les patients se nourrissent des travaux de la psychopathologie phénoménologique (Blankenburg, Minkowski, Tatossian, Stanghellini, Sass, …) et se veulent un aller-retour constant entre théorie et clinique. Dans ce contexte, nous approfondirons l’hypothèse proposée par Louis Sass selon laquelle la folie, du moins dans certaines de ses formes, pourrait dériver d’une intensification plutôt que d’un affaiblissement de la conscience. L’hyper-réflexivité schizophrénique – indiquant une focalisation explicite et réflexive sur des phénomènes a priori implicites et préréflexifs – sera particulièrement analysée à partir des descriptions recueillies. Après avoir développé, à partir des cas cliniques, cette hypothèse d’une « hyper-conscience » comme symptôme cardinal de l’expérience subjective de la schizophrénie, nous analyserons les implications du recours à la perspective en « première personne » sur la prise en charge, les modèles de soins et la manière de concevoir le rapport au monde de ces patients. [less ▲]

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See detailMeasurement of Innovation: Where Do We Stand?
Artige, Lionel ULg

Conference (2016, September 08)

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See detailUnified treatment of microscopic boundary conditions in computational homogenization method for multiphysics problems
Nguyen, Van Dung ULg; Wu, Ling ULg; Homsi, Lina ULg et al

Conference (2016, September 08)

Computational homogenization (so-called FE2) method is an effective tool to model complex behavior of heterogeneous media allowing direct coupling between the structure response and the evolving ... [more ▼]

Computational homogenization (so-called FE2) method is an effective tool to model complex behavior of heterogeneous media allowing direct coupling between the structure response and the evolving microstructure not only in purely mechanical problems but also in multiphysics problems [1]. The basic idea of this method is to obtain the macroscopic constitutive relationships from the resolution of the microscopic boundary value problem (BVP) defined on a representative volume element. This method does not requires any constitutive assumption at the macroscopic level, but an appropriate microscopic boundary condition has to be defined. Our work focuses on the unified treatment of the microscopic boundary condition in a multiphysics microscopic BVP. In particular, an efficient way to compute the tangent operator is developed for an arbitrary kind of boundary conditions. When considering the FE2method, the homogenized stresses and homogenized tangents at every macroscopic integration points are required. From the energy consistency condition between macroscopic and microscopic problems, the homogenized stresses can be easily computed by the volumetric averaging integrals of the microscopic counterparts. The required homogenized tangents often follows a stiffness condensation from the microscopic stiffness matrix at the equilibrium state [2]. When using the stiffness condensation, the microscopic stiffness matrix needs to be partitioned, and dense matrices based on Schur complements (under a matrix form 𝐊̃ 𝑏𝑏=𝐊𝑏𝑏−𝐊𝑏𝑖𝐊𝑖𝑖−1𝐊𝑖𝑏) have to be estimated. The matrix operations based on Schur complements require a large time consuming and a lot of memory when increasing the number of degrees of freedom of the microscopic BVPs. This work proposes an efficient method allowing to compute the homogenized tangents without significant effort. The microscopic stiffness matrix does not need to be partitioned. The homogenized tangents are computed by solving a linear system, which is based on the linearized system at the converge solution of the microscopic BVP, with multiple right hand sides. With proposed numerical improvements, the FE2 method is used in a fully thermo-mechanically-coupled simulation. The temperature-dependent elastoplastic behavior, thermal conduction as well as the heat conversion from the mechanical deformation are considered in the hyperelastic large strain framework. [1]. Geers, M. G. D., Kouznetsova, V. G., Brekelmans, W. A. M., 2010. J. Comput. Appl. Math. 234 (7), 2175-2182. [2]. Kouznetsova, V., Brekelmans, W. A. M., Baaijens, F. P. T., 2001. Comput. Mech. 27 (1), 37-48. [less ▲]

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See detailSécurité et santé au travail dans les bassins miniers wallons des années ’50
Geerkens, Eric ULg

Conference (2016, September 08)

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See detailSimulations of composite laminates inter and intra-laminar failure using on a non-local mean-field damage-enhanced multi-scale method
Wu, Ling ULg; Adam, Laurent; Bidaine, Benoît et al

Conference (2016, September 07)

The failure of carbon fiber reinforced composite laminates is studied using a multiscale method. A non-local mean-field homogenization (MFH) method accounting for the damage evolution of the matrix phase ... [more ▼]

The failure of carbon fiber reinforced composite laminates is studied using a multiscale method. A non-local mean-field homogenization (MFH) method accounting for the damage evolution of the matrix phase of the composite material [1] is considered in each ply in order to capture the intra-laminar failure. In that formulation, an incremental-secant MFH approach is used to account for the elastic unloading of the fibers during the strain softening of the matrix. In order to avoid the strain/damage localization caused by the matrix material softening, the damage enhanced MFH was formulated in an implicit non-local way [2]. Accurate predictions of the composite softening behavior and of the different phases response is then achieved. The delamination process is modeled by recourse to a hybrid discontinuous Galerkin (DG)/ extrinsic cohesive law approach. An open-hole composite laminate with a quasi-isotropic sequence ([90/45/-45/90/0]S) is then studied experimentally and using the multiscale method [3]. The numerical model is found to predict the damage bands along the fiber directions in agreement with the experimental samples inspected by X-ray computed tomography (XCT). Moreover, the predicted delamination pattern is found to match the experimental observations. Finally, with a view to stochastic analysis, the effect of the volume fraction and orientation variations on the failure is studied by defining them as random variables. REFERENCES [1] L. Wu, L. Noels, L. Adam, I. Doghri, An implicit-gradient-enhanced incremental-secant mean- field homogenization scheme for elasto-plastic composites with damage, International Journal of Solids and Structures, 50, 3843-3860, 2013. [2] R. Peerlings, R. de Borst, W. Brekelmans, S. Ayyapureddi, Gradient-enhanced damage for quasi-brittle materials. International Journal for Numerical Methods in Engineering, 39, 3391-3403, 1996. [3] L. Wu, F. Sket, J.M. Molina-Aldareguia, A. Makradi, L. Adam, I. Doghri, L. Noels, A study of composite laminates failure using an anisotropic gradient-enhanced damage mean-field homogenization model, Composite Structures, 126, 246–264, 2015. [less ▲]

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See detailInterfaces in multi-material architectures fabricated by polyjet printing
Zorzetto, Laura ULg; Rink, Marta; Briatico Vangosa, Francesco et al

Conference (2016, September 07)

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See detailHow do droplets form?
Van Loo, Stéphanie ULg; Stoukatch, Serguei ULg; Kraft, Michael ULg et al

Poster (2016, September 07)

In microfluidics, flow focusing is widely used to produce water-in-oil droplets in microchannels at high frequency. We here report an experimental study of droplet formation in a microfluidic cross ... [more ▼]

In microfluidics, flow focusing is widely used to produce water-in-oil droplets in microchannels at high frequency. We here report an experimental study of droplet formation in a microfluidic cross-junction with a minimum number of geometrical parameters. We mostly focus on the squeezing regime, which is com- posed of two distinct steps : filling and pinching. The duration of each step (and corresponding volumes of each liquid phase) are analyzed. They vary according to both water and oil flow rates. These variations provide several insights about the fluid flows in both phases. We propose several scaling laws to relate the droplet volume and frequency to the flow rate of both phases. We also discuss the influence of surfactant and channel compliance on droplet formation. [less ▲]

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See detailA coupled electro-thermo-mechanical discontinuous Galerkin method applied on composite materials
Homsi, Lina ULg; Noels, Ludovic ULg

Conference (2016, September 07)

Carbon fiber reinforced polymer composites have become increasingly important due to their unique properties which are appreciated in many practical applications such as low weight, low cost, low density ... [more ▼]

Carbon fiber reinforced polymer composites have become increasingly important due to their unique properties which are appreciated in many practical applications such as low weight, low cost, low density, high mechanical characteristics. Moreover the range of their electrical conductivity can be controlled by the amount of carbon fibers. Carbon fiber reinforced polymer composites consist of at least two components, a polymer matrix (generally dielectric) and electrically conductive fillers. This combination results in multifunctional composites, both structural and conductive. The existence of the polymer matrix will avoid catastrophic failure due to fiber breaking, and the existence of the carbon fibers will enhance strength and stiffness on one hand, and will allow to a significant temperature gradient when electric current is applied on the other hand. The objective of this paper is to study the response of the carbon fiber reinforced polymer composites when an electric power is applied and to determine the effective properties. To this end governing equations describing electro-thermo-mechanical coupling in composite materials are developed and discretized using the Discontinuous Galerkin (DG) finite element method. DG methods have many advantages such as optimal convergence and local approximation properties in addition to their flexibility for mesh adaption and their straightforward use of high order polynomial approximations. A micromechanical model of unidirectional carbon fibers dispersed in a polymer matrix is formulated considering the interaction of electrical, thermal and mechanical fields It is then solved using the DG method to determine the time dependent response of the electro-thermo-mechanical coupling and quantify the variation of the fields. [less ▲]

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See detailBetween bovine milk production and reproduction : the challenge.
Hanzen, Christian ULg; Nguyen Kien, Cuong

in Vo Thi Tra; Ho Thi Kim, Hoa; Le Thanh, Hien (Eds.) et al Proceedings of the 19th Federation of Asian Veterinary Association Congress (2016, September 07)

Huge differences in dairy milk production can be observed around the world. They can be explained by differences in genetic, nutritional resources and management including the capacities of the farmers ... [more ▼]

Huge differences in dairy milk production can be observed around the world. They can be explained by differences in genetic, nutritional resources and management including the capacities of the farmers and veterinarian to prevent and treat the different pathologies inducing of the wellbeing of the animals. According to the world market of milk production, the challenge of each farm is not only to produce a milk of quality but also to reduce the costs of milk production by improving reproductive performances. Anywhere in the world we are responsible to encourage and develop a sustainable approach of milk production and agriculture development according to his three pillars: environment, economic and social. Our presentation will present (1) the mains figures about the milk production in the world, (2) the definitions and prevalences of the different periods involved in the reproductive life of a cow, (3) the nutritional, genetic and pathological factors involved in the milk production on general and more specifically in reproduction (dystocia, placental retention, uterine infections, postpartum anoestrus), the relationships between these factors, (‘) the state of art of the definition, methods of diagnostic state of art of the main reproduction pathologies (dystocia,) affecting the dairy cows during the waiting and reproduction periods. [less ▲]

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See detailGeneralized Pascal triangle for binomial coefficients of words : an overview
Stipulanti, Manon ULg

Conference (2016, September 07)

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word ... [more ▼]

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word. Similarly to the Sierpiński gasket that can be built as the limit set, for the Hausdorff distance, of a convergent sequence of normalized compact blocks extracted from Pascal triangle modulo 2, we describe and study the first properties of the subset of [0, 1] × [0, 1] associated with this extended Pascal triangle modulo a prime p. Then we create a new sequence from this extended Pascal triangle that counts, on each row of this triangle, the number of positive binomial coefficients. We study some properties of this sequences. To be precise, we investigate some properties regarding the regularity of the sequence. To extend our work, we construct a Pascal triangle using the Fibonacci representations of all the nonnegative integers and we define the corresponding sequence of which we study the regularity. This regularity is an extension of the classical k-regularity of sequences. [less ▲]

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See detailMagnetic shielding above 1 T at 20 K with bulk, large grain YBCO tubes made by Buffer-aided Top Seeded Melt Growth.
Wera, Laurent ULg; Fagnard, Jean-François ULg; Kumar, Nambury Devendra et al

Poster (2016, September 07)

A superconducting tube can be used as an efficient magnetic shield. The best shielding performance levels are usually achieved when the tube is closed at one or both extremities. The purpose of the ... [more ▼]

A superconducting tube can be used as an efficient magnetic shield. The best shielding performance levels are usually achieved when the tube is closed at one or both extremities. The purpose of the present work is to study experimentally the shielding performance of YBCO tubes obtained by Buffer-aided Top Seeded Melt Growth fabrication process (BA-TSMG). This fabrication process enables the tube to be closed at one extremity by a cap containing the seed and there is no air gap between the cap and the tube. The shielding effectiveness is characterized by two parameters: (i) the shielding factor, defined as the ratio between the applied magnetic induction and the local magnetic induction measured inside the shield, and (ii) the threshold induction, i.e. the applied magnetic induction above which a given value of the shielding factor cannot be achieved. The magnetic shielding performances of tubes with different geometry are characterized at 77 K in liquid nitrogen. Further magnetic shielding measurements are carried out on one tube at various temperatures ranging from 20 K to 77 K using a Physical Property Measurement System (PPMS). The tubes are subjected to a quasi-static (“DC”) uniform magnetic field. A Hall probe measures the axial component of the local magnetic induction along the axis of the tube as a function of the applied magnetic induction. In order to investigate how the cap prevents the magnetic flux from penetrating inside the tube, we also characterize open tubes where the cap is removed and compare their properties to those of closed tubes. Magnetic shielding measurements show that the threshold induction increases by a factor of 9 as temperature decreases from 77 K to 20 K. Measurements also show that the presence of the cap improves the shielding performance at the closed extremity of the order of 1000 as it reduces the penetration through the open end. Near the closed extremity, a threshold induction of 1.5 T was reached at 20 K. To our knowledge this threshold induction is the best value reported so far at 20 K, and is comparable in magnitude to the record threshold inductions reported for bulk MgB2 and Bi-2212 materials at lower temperatures. These results give evidence that efficient magnetic shields can be obtained with this fabrication technique. [less ▲]

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See detailGPS, Galileo and BeiDou inter-system biases estimation in relative positioning with code and phase pseudoranges
Deprez, Cécile ULg; Warnant, René ULg

Conference (2016, September 07)

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the Chinese BeiDou satellite system and the ... [more ▼]

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the Chinese BeiDou satellite system and the European Galileo program have experienced major progress in 2015 and 2016 with the launch of 7 and 8 satellites respectively. Associated with the ongoing GPS modernization, many more frequencies and satellites are now available. Therefore, multi-GNSS relative positioning based on overlapping frequencies should entail better accuracy and reliability in position estimations. However, the differences between satellite systems induce inter-system biases (ISBs) inside the multi-GNSS equations of observation. The combined use of L1 and L5 from GPS with E1 and E5a from Galileo, B2 from BeiDou and E5b from Galileo in zero baseline double differences (ZB DD) based on a unique pivot satellite is employed to resolve ISBs. This model removes all the satellite- and receiver-dependent error sources by differentiating and the zero baseline configuration allows atmospheric and multipath effects elimination. An analysis of the long-term stability of ISBs (GPS- Galileo and Galileo - BeiDou) is conducted onvariouspairsof receiversover large timespans. Thepossibleinfluenceof temperature variations inside the receivers over ISB values is also investigated. Our study is based on the 6 multi-GNSS receivers (2 Septentrio PolaRx4, 1 Septentrio PolaRxS, 1 Septentrio PolaRx5 and 2 Trimble NetR9) installed on the roof of our building in Liege. The estimated ISBs are then used as corrections in the multi-GNSS observation model and the resulting accuracy of multi-GNSS positioning is compared to GPS, Galileo and BeiDou standalone solutions. [less ▲]

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See detailUltra-narrow superconducting junctions: electromigration to shed light on quantum point contacts
Baumans, Xavier ULg; Cerbu, Dorin; Adami, Obaïd-Allah ULg et al

Conference (2016, September 06)

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and in quantum computing circuits. In this context, it is of ... [more ▼]

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and in quantum computing circuits. In this context, it is of fundamental importance to better understand the undesired and harmful appearance of thermal and quantum fluctuations of the superconducting order parameter [1]-[3] as a function of the wire width. Although superconductors in the mesoscopic regime (i.e. size comparable to ξ and/or λ) have been explored both experimentally and theoretically in depth, the superconducting nanoworld (i.e. at scales of the fermi wavelength) has received much less attention. The lack of experimental results is in part due to the difficulty of sample fabrication, at dimensions beyond the limit reached by conventional lithographic techniques. A promising direction consists of controlling the local displacement of atom by an electron wind, a process known as electromigration (EM) [4] . This effect relies on the combination of local temperature rise and substantial current crowding at nanoconstrictions. While uncontrolled, EM is responsible for the breakdown of small electronic devices, it can be used in a controllable way to further decrease locally the cross section of the nanowire towards single atomic contacts. In this work, we explore in-situ controlled EM to fabricate nano-constrictions immersed in cryogenic environment. We demonstrate that a transition from thermally assisted phase slips (TAPS) to quantum phase slips (QPS) takes place when the effective cross section becomes smaller than ~ 150 nm 2 . In the regime dominated by QPS the nanowire loses completely its capacity to carry current without dissipation, even at the lowest possible temperature [5] . We also demonstrate that the bow-tie shaped constrictions exhibit a negative magnetoresistance at low magnetic fields [5] which can be attributed to the suppression of superconductivity in the contact leads [6] . Strikingly, the detrimental effect caused by the repeated EM can be healed by simply inverting the current direction. These findings reveal the strong potential of the proposed fabrication method to explore various fascinating superconducting phenomena in atomic-size constrictions. [less ▲]

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See detailProbabilistic Measures of Earthquake Effects on Fire Performance of Tall Buildings
Elhami Khorasani, Negar; Gernay, Thomas ULg; Garlock, Maria

in Zingoni (Ed.) Proceedings of the Sixth International Conference on Structural Engineering, Mechanics and Computation (2016, September 06)

Cascading multi-hazard events, such as fires following an earthquake, can trigger progressive collapse of structures. Risk or the probability of reaching a limit state after an extreme event is related to ... [more ▼]

Cascading multi-hazard events, such as fires following an earthquake, can trigger progressive collapse of structures. Risk or the probability of reaching a limit state after an extreme event is related to (a) the probability of occurrence of the hazard, and (b) the probability of reaching the limit state given the hazard. In this paper, earthquake effects on fire performance of tall buildings in a community are studied. First, the proba-bility of fire ignition due to an earthquake is modeled based on historical data and properties of the built en-vironment. In the second step, the effect of earthquake on structural fire performance of a steel frame is studied using system level probabilistic approaches. The results show that the earthquake does not increase the probability of reaching different limit states under fire, however, post earthquake fire can increase the drift demand on columns located on the perimeter of the structure, and may cause instability. [less ▲]

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See detailAre Christmas tree plantations a suitable habitat for farmland birds?
Gailly, Robin ULg; Paquet, Jean-Yves; Titeux, Nicolas et al

Conference (2016, September 06)

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may ... [more ▼]

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may likely impact farmland birds. Impacts on birds have been examined for bioenergy agricultural systems, such as miscanthus plantations and short rotation willow coppice. In Europe, the extend of Christmas tree plantations (CTP) has recently increased dramatically in farmland but their impacts on farmland birds remains largely unknown. We examined the extent to which CTP in southern Belgium alter bird species assemblages compared to traditional farmland. The presence and abundance of birds were recorded twice during a breeding season in randomly selected sites located in farmland areas with and without CTP. Results show that the conversion of traditional farmland into CTP modifies bird species assemblages and locally increases bird diversity and density without inducing biotic homogenization. This observed pattern indicates that CTP might constitute an interesting alternative habitat for farmland birds. However bird presence or abundance may be confounding indicator of habitat quality because individuals may be attracted to low-quality habitats in human modified landscapes. The European Stonechat Saxicola rubicola was chosen as a model species to investigate the quality of CTP as a breeding habitat in more details. Habitat quality in CTP was assessed with measures of reproductive success and survival. These measures were compared with those collected in traditional farmland. Although vegetation structure, field management and nest placement are highly different between habitat types, our first results suggest that CTP are not of lesser quality than traditional farmland for the European Stonechat. [less ▲]

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See detailAre Christmas tree plantations a suitable habitat for farmland birds?
Gailly, Robin ULg; Paquet, Jean-Yves; Titeux, Nicolas et al

Poster (2016, September 06)

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may ... [more ▼]

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may likely impact farmland birds. Impacts on birds have been examined for bioenergy agricultural systems, such as miscanthus plantations and short rotation willow coppice. In Europe, the extend of Christmas tree plantations (CTP) has recently increased dramatically in farmland but their impacts on farmland birds remains largely unknown. We examined the extent to which CTP in southern Belgium alter bird species assemblages compared to traditional farmland. The presence and abundance of birds were recorded twice during a breeding season in randomly selected sites located in farmland areas with and without CTP. Results show that the conversion of traditional farmland into CTP modifies bird species assemblages and locally increases bird diversity and density without inducing biotic homogenization. This observed pattern indicates that CTP might constitute an interesting alternative habitat for farmland birds. However bird presence or abundance may be confounding indicator of habitat quality because individuals may be attracted to low-quality habitats in human modified landscapes. The European Stonechat Saxicola rubicola was chosen as a model species to investigate the quality of CTP as a breeding habitat in more details. Habitat quality in CTP was assessed with measures of reproductive success and survival. These measures were compared with those collected in traditional farmland. Although vegetation structure, field management and nest placement are highly different between habitat types, our first results suggest that CTP are not of lesser quality than traditional farmland for the European Stonechat. [less ▲]

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See detailYes we can! Implementing digitization requests in Alma
Renaville, François ULg; Brownlie, Helen; Read, Simon et al

Conference (2016, September 06)

Enabling patron digitization requests is one of those (new) exciting services that end users appreciate! Alma allows patrons and staff members to request the creation of a digital file for any physical or ... [more ▼]

Enabling patron digitization requests is one of those (new) exciting services that end users appreciate! Alma allows patrons and staff members to request the creation of a digital file for any physical or electronic item. Alma digitization request workflow is configurable according to the library’s requirements, created via Alma or Primo, partial or full, limited to some user groups, limited in numbers, with or without approval process, digitized materials added to collections and made accessible to registered and/or guest users via Primo, etc. So Alma libraries can deal with a lot of different options to satisfy their patrons' needs. This session will present the development and launch of digital fulfillment from the perspective of 3 institutions (the University of Otago Library, the University of Liege Library, and the University of Sheffield Library) focusing on the strategic choices that were made, the implementation, and the final delivery of the services to their communities. [less ▲]

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See detailThree-Parameter Kinematic Approach for Shear Behaviour of Short Coupling Beams with Conventional Reinforcement
Mihaylov, Boyan ULg; Franssen, Renaud

in fib bulletin (in preparation) (2016, September 06)

This paper presents a three-parameter kinematic theory (3PKT) for predicting the shear strength and deformation patterns of short coupling beams. The 3PKT approach is situated between simple and ... [more ▼]

This paper presents a three-parameter kinematic theory (3PKT) for predicting the shear strength and deformation patterns of short coupling beams. The 3PKT approach is situated between simple and conservative strut-and-tie models and complex non-linear finite element (FE) models. It is aimed at improving the shear strength predictions of strut-and-tie models while maintaining relative simplicity and clear physical basis. In addition, it is aimed at providing estimates of the ultimate deformations in coupling beams which are typically calculated with FE models. While FE models use a large number of degrees of freedom (DOFs) to describe the deformation patterns in coupling beams, the 3PKT is based on a kinematic model with only three DOFs. In addition to kinematic conditions, the 3PKT also includes equilibrium equations and constitutive relationships for the mechanisms of shear resistance in short coupling beams. The paper presents the formulation of the 3PKT and compares its shear strength predictions to results from tests, finite element simulations, and strut-and-tie models. It is shown that the 3PKT approximates very well the predictions of the FE models, while the strut-and-tie model produce significantly lower strengths. [less ▲]

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See detailPhase Slips In Tunable Width Point Contacts Created By Electromigration
Silhanek, Alejandro ULg

Conference (2016, September 05)

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and as interconnects in circuits proposed for quantum computing ... [more ▼]

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and as interconnects in circuits proposed for quantum computing. In this context, it is of fundamental importance to better understand the undesired and harmful appearance of thermal and quantum fluctuations of the superconducting order parameter as a function of the wire width. In this presentation, we explore in-situ controlled electromigration (EM) to fabricate nano-constrictions immersed in cryogenic environment. We demonstrate that a transition from thermally assisted phase slips (TAPS) to quantum phase slips (QPS) takes place when the effective cross section becomes smaller than ~150 nm^2. In the regime dominated by QPS the nanowire loses completely its capacity to carry current without dissipation, even at the lowest possible temperature. We also demonstrate that the bow-tie shaped constrictions exhibit a negative magnetoresistance at low magnetic fields which can be attributed to the suppression of superconductivity in the contact leads. Strikingly, the detrimental effect caused by the repeated EM can be healed by simply inverting the current direction. These findings reveal perspectives of the proposed fabrication method for exploring various fascinating superconducting phenomena in atomic size constrictions. [less ▲]

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See detailUnusually high sea ice cover influences resource use by benthic invertebrates in coastal Antarctica
Michel, Loïc ULg; Dubois, Philippe; Eleaume, Marc et al

Poster (2016, September 05)

Antarctica currently undergoes strong and contrasted impacts linked with climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice ... [more ▼]

Antarctica currently undergoes strong and contrasted impacts linked with climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice cover decrease, the sea ice cover of East Antarctica unexpectedly tends to increase, possibly in relation with changes in atmospheric circulation. Changes in sea ice cover are likely to influence benthic food web structure through modifications of benthic-pelagic coupling, disruption of benthic production and/or modifications of benthic community structure (i.e. resource availability for benthic consumers). Here, we studied shallow (0-20 m) benthic food web structure on the coasts of Petrels Island (Adélie Land, East Antarctica) during an event of unusually high spatial and temporal (two successive austral summers without seasonal break-up) sea ice cover. Using stable isotope ratios of C and N and the SIAR mixing model, we examined importance of 4 organic matter sources (benthic macroalgae, benthic biofilm, sympagic algae, suspended particulate organic matter) for nutrition of dominant primary consumers and omnivores. 14 invertebrate taxa including sessile and mobile polychaetes, gastropods, bivalves, sea stars, sea urchins and sea cucumbers were studied. Our results indicate that most benthic invertebrates predominantly relied on sympagic algae. Despite its very high abundance, trophic role of benthic biofilm seemed limited. However, interpretation of data was complicated by the peculiar ecophysiological features of Antarctic invertebrates, whose very low metabolic rates could be associated to low isotopic turnover and long time to reach isotopic equilibrium with their food items. Resource use by consumers from Adélie Land markedly differed from literature data about invertebrate diet in coastal Antarctica, suggesting 1) important influence of increased sea ice cover on benthic food web structure and 2) high spatial and/or temporal variation in the feeding habits of studied organisms, likely linked with a high degree of trophic plasticity. Our results provide insights about how Antarctic benthic consumers, which have evolved in an extremely stable environment, might adapt their feeding habits in response to sudden man-driven changes in environmental conditions and trophic resource availability. [less ▲]

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See detailFlipped classes and enriched skeleton maps to foster deep and interactive learning in engineering education
Attia, Shady ULg; Detroz, Pascal ULg

in Mazijn (Ed.) BUILDING A CIRCULAR ECONOMY TOGETHER (2016, September 05)

This paper reports the initial experience of applying the enriched skeleton mapping technique as innovative and meaningful learning methods within a flipped class teaching setting. Driven by the low ... [more ▼]

This paper reports the initial experience of applying the enriched skeleton mapping technique as innovative and meaningful learning methods within a flipped class teaching setting. Driven by the low confidence and autonomy of many undergraduates; this study focus on stimulating collaboration and interactive learning. The study was performed in a course labeled ‘sustainable building construction technology’ of the Bachelor of Architectural Engineering program at Liege University (Ulg). First year and second year students, were assigned to an experimental group of 27 students and a control group of 8. In the experimental group, students worked together in pairs on mini-concepts and created enriched skeleton maps for the course content. The control group received a regular ex-cathedra course. The results show that students who used the enriched skeleton mapping technique were more engaged and outperformed the control group. Enriched skeleton concept mapping fostered deep learning and resulted in a better understanding of the course mini concepts in addition to the course structure and domain. Students of the enriched skeleton mapping found learning to be more ‘useful, stimulating and more engaging’, whereas students of the congenital ex-cathedra curriculum found learning to be ‘passive and boring’. A combination of both techniques may provide the most effective training for undergraduate engineering students. [less ▲]

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See detailTraining engineers to meet the challenges of a changing world: how a competency framework improves teaching programs and team cohesion
Degré, Aurore ULg; Colaux, Catherine ULg

in Mazijn, Bernard (Ed.) 8th Conference on Education engineering for sustainable development (2016, September 05)

The competency framework is a complex and time-consuming exercise seen by most teachers as an administrative process. When applied, however, it can be a powerful tool for adapting curricula for engineers ... [more ▼]

The competency framework is a complex and time-consuming exercise seen by most teachers as an administrative process. When applied, however, it can be a powerful tool for adapting curricula for engineers to meet the emerging needs of society, including training in sustainable development. This paper looks at how to use the competency framework to generate a tool for bringing teachers together around shared objectives, helping students build their career paths and improving communication with the ‘outside world’. This approach, largely inspired by the Tardif approach, is being used for the Bioengineering Masters Degree in Environmental Sciences and Technology at the Gembloux Agro-Bio Tech Faculty, University of Liège, Belgium. The approach has allowed the teaching staff to build a common educational project aimed at enabling bioengineers to meet the needs of society [less ▲]

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See detailInternet Platforms for Education on Sustainability
Pfennig, Andreas ULg

Conference (2016, September 05)

One challenge in teaching sustainability results from the expertise being distributed in various universities. At the same time society would not require so many experts focused on sustainability that ... [more ▼]

One challenge in teaching sustainability results from the expertise being distributed in various universities. At the same time society would not require so many experts focused on sustainability that corresponding purely sustainability-oriented curricula should be offered in a majority of universities. Thus sustainability aspects have to be integrated into existing curricula e.g. in chemical engineering studies. To offer sufficiently high-level courses or teaching content, one way is to share modules dealing with sustainability aspects. The idea to share teaching capabilities on a national or international level is not new, some examples are sustainicum.at, bioenergytrain.eu. While these approaches address the topic of sustainability with a relatively wide variety of facets, it is difficult to see, how a coherent picture can be obtained and transferred in education to students and the interested public. While this is so, already regarding the most basic element of the versatile toolbox of chemical engineering, namely setting up and solving simple balances, leads to significant insights and especially a fundamental understanding on the basic interplay of at least some of the major drivers. These are – besides increasing world population, which is the main driver – the increasing energy consumption, the limited land area for food and bioenergy production, the finite size even of the atmosphere leading to an increase in CO2 concentration and climate change, to name just a few. All of these aspects refer to limited resources for which balances can be set up and solved. The balances have the advantage that they are so simple that everybody can assess their validity and implications. The experience with working out a corresponding teaching module will be presented exemplarily. To facilitate delivering the aspects to students and the interested public the teaching material including a full manuscript and power-point slides have been worked out and are supplied at sustainicum.at. To allow easy access to the content of this teaching material also corresponding lectures have been recorded and are made publicly available through YouTube. The technical boundary conditions, which were found to be quite optimal as compared to other public lectures available on the internet, will be presented. The teaching material has in the past also been used for a variety of own presentations with the aim to deliver the basic understanding to an interested public, including public conference series or school classes. From these various experiences conclusions are drawn which will be presented. Introduction: One challenge in teaching sustainability results from the expertise being distributed in various universities. At the same time society would not require so many experts focused on sustainability that corresponding purely sustainability-oriented curricula should be offered in a majority of universities. Thus sustainability aspects have to be integrated into existing curricula e.g. in chemical engineering studies. To offer sufficiently high-level courses or teaching content, one way is to share modules dealing with sustainability aspects. The idea to share teaching capabilities on a national or international level is not new, some examples are sustainicum.at, bioenergytrain.eu. While these approaches address the topic of sustainability with a relatively wide variety of facets, it is difficult to see, how a coherent picture can be obtained and transferred in education to students and the interested public. Exemplary Topic: While this is so, already regarding the most basic element of the versatile toolbox of chemical engineering, namely setting up and solving simple balances, leads to significant insights and especially a fundamental understanding on the basic interplay of at least some of the major drivers. These are – besides increasing world population, which is the main driver – the increasing energy consumption, the limited land area for food and bioenergy production, the finite size even of the atmosphere leading to an increase in CO2 concentration and climate change, to name just a few. All of these aspects refer to limited resources for which balances can be set up and solved. The balances have the advantage that they are so simple that everybody can assess their validity and implications. The experience with working out a corresponding teaching module will be presented exemplarily. Results and Conclusions: To facilitate delivering the aspects to students and the interested public the teaching material including a full manuscript and power-point slides have been worked out and are supplied at sustainicum.at. To allow easy access to the content of this teaching material also corresponding lectures have been recorded and are made publicly available through YouTube. The technical boundary conditions, which were found to be quite optimal as compared to other public lectures available on the internet, will be presented. The teaching material has in the past also been used for a variety of own presentations with the aim to deliver the basic understanding to an interested public, including public conference series or school classes. From these various experiences conclusions are drawn which will be presented. [less ▲]

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See detailIntroducing regenerative design and circularity into architectural and engineering curriculum
Attia, Shady ULg

in Mazijn (Ed.) BUILDING A CIRCULAR ECONOMY TOGETHER (2016, September 05)

Looking today to the challenges for planning and design of sustainable built environment including, carbon emissions, climate change, human health, water problems, biodiversity, scarcity of resources ... [more ▼]

Looking today to the challenges for planning and design of sustainable built environment including, carbon emissions, climate change, human health, water problems, biodiversity, scarcity of resources, depletion of fossil fuel, population growth and urbanization; sustainable architecture will play a key role for the sustainable development of society as a whole. In the context of an architectural design studio, this paper presents the experience of introducing the concept of regenerative design within a Belgian engineering faculty. The regenerative design objective and principles are used as a method to develop engineers’ capabilities to design within a circular economy paradigm. The aim of the study is to evaluate the adoption of circular economy principles and their influence on the decision making and final outcomes on third-year architectural engineering students at the University of Liege (Ulg), Faculty of Applied Sciences in 2014 and 2015. The paper utilizes two design studios outcomes in the form of projects evaluation and students feedback, in the form of interviews and surveys, in order to assess the students’ knowledge uptake, learned skills and design capabilities. Students completed a knowledge, skills, and attitudes questionnaire before the curriculum, after the final learning experience, and one year later. The paper provides results that shed light on the opportunities, challenges and architectural engineer’s needs to engage in a circular built environment. [less ▲]

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See detailImprinting superconducting vortex trajectories in a magnetic layer
Shaw, Gorky ULg

Conference (2016, September 05)

We experimentally show that the principle of local polarization of a magnetic layer can be applied for imprinting, into a soft magnetic layer of permalloy (Py), the trajectory of vortices moving in a ... [more ▼]

We experimentally show that the principle of local polarization of a magnetic layer can be applied for imprinting, into a soft magnetic layer of permalloy (Py), the trajectory of vortices moving in a superconducting film (Nb). In full analogy with a magnetic drawing board, vortices act as tiny magnetic scribers leaving a wake of polarized magnetic media in the Py layer. We have used the magneto-optical imaging technique to investigate the mutual interaction between superconducting vortices and ferromagnetic domains. In general, we observe that the flux propagation is delayed at the border of the magnetic layer. For thick Py layers, the stripe magnetic domain pattern guides the smooth flux penetration as well as the abrupt vortex avalanches in the Nb film. More interestingly, in thin Py layers without stripe domains, vortices leave clear imprints of locally polarized magnetic moments along their trajectories. Furthermore, the printings were found to be stable and could still be observed at room temperature, allowing for ex situ observation of the flux penetration in superconductors. We expect our findings to pave the way for further studies for optimizing magnetic recording of superconducting vortex trajectories. [less ▲]

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See detailBalanced words and related concepts: applications and complexity issues
Crama, Yves ULg

Conference (2016, September 05)

In this talk, I present a few results and several questions about "regular" sequences of integers and related concepts, such as balanced words, partitions and covers of the integers by arithmetic ... [more ▼]

In this talk, I present a few results and several questions about "regular" sequences of integers and related concepts, such as balanced words, partitions and covers of the integers by arithmetic sequences. Such concepts have been investigated in pure mathematics, but also naturally arise in a variety of application fields such as production planning, political science, or queueing theory. I briefly present some of these applications and explain how they motivate seemingly new questions relating, for instance, to the algorithmic complexity of regular partitions, or to the structure of balanced words. The presentation is based on joint work with Nadia Brauner and Vincent Jost (Grenoble). [less ▲]

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See detailFeeding ecology of Southern Ocean seastars inferred from stable isotopes ratios
Le Bourg, Baptiste ULg; Blanchard, Alice; Danis, Bruno et al

Poster (2016, September 05)

The Southern Ocean is currently subjected to strong and contrasted impacts of climate change. The Western Antarctic Peninsula is one of the most rapidly warming regions of the world, resulting in sea ice ... [more ▼]

The Southern Ocean is currently subjected to strong and contrasted impacts of climate change. The Western Antarctic Peninsula is one of the most rapidly warming regions of the world, resulting in sea ice cover decreases. Increasing seawater temperature and sea ice cover reduction in Western Antarctic Peninsula and associated regions will likely impact food web functioning through temperature-related changes in consumer physiology, modifications of benthic community structure (e.g. expansion of exogenous species such as predatory crabs), modifications of benthic-pelagic coupling intensity or disruption of benthic production. Asteroids (Echinoderms) are an important group of southern benthos. This group also has a great trophic variability and is potentially more resistant than other organisms to temperature changes (Peck et al. 2008). Consequently, they will be likely impacted by modifications in food webs functioning rather by direct warming and investigating their trophic ecology is necessary to infer how climate change will impact them. In this context, the aim of this study is to use stable isotopes ratios of C, N and S to infer sea stars trophic ecology. 16 species of sea stars spanning 10 different families sampled in multiple and contrasted habitats across Subantarctic (South Georgia, South Sandwich Islands, Falkland Islands) and Antarctic (South Shetland Islands, South Orkney Islands, Western Antarctic Peninsula) locations. In total, tegument samples from 213 specimens was analysed. Diversity and plasticity of asteroid diet along Southern Ocean coasts were explored through isotopic niche parametrisation (e.g. niche width and overlap between species and/or populations; Jackson et al. 2011). The data will also be used in a larger scale research project on the trophic ecology of Antarctic sea stars. This project will notably compare trophic resources supporting asteroid communities in Western Antarctic Peninsula, where sea ice cover is decreasing, and in Terre Adélie, where sea ice cover is increasing (Parkinson & Cavalieri 2012). Ultimately, this project will help understanding which ecological processes determine how an animal group copes with environmental modifications linked to climate change. [less ▲]

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See detailInstability and abrupt changes in marine ice sheet behaviour
Bulthuis, Kevin ULg; Arnst, Maarten ULg; Pattyn, Frank et al

Conference (2016, September 05)

The West Antarctic ice sheet (WAIS), whose bedrock is to a large extent below sea level, has been identified as a tipping element in Earth’s climate system because it could dramatically re- treat and ... [more ▼]

The West Antarctic ice sheet (WAIS), whose bedrock is to a large extent below sea level, has been identified as a tipping element in Earth’s climate system because it could dramatically re- treat and cause important sea-level rise. Different mechanisms underlying instabilities of such marine ice sheets have been proposed in the literature, but the risk that these mechanisms could trigger an accelerated retreat of the WAIS is still an open question. In this oral communication, which results from the literature study that I carried out during this ongoing first year of my PhD, I will review two main mechanisms that can cause marine ice sheet instability. The first mechanism is the marine ice sheet instability explained by Weertman who hypothe- sizes that marine ice sheets grounded on bedrocks which deepen inland can be inherently unstable. I will focus my attention on the stability of the steady states of this nonlinear dyna- mical system, as well as on the critical values of the external forcing parameters responsible for abrupt changes in the system behaviour (critical transitions). I will review how geological data suggest that rapid ice sheet retreats explained by Weertman’s hypothesis occurred in Antarctica during the Pleistocene and the early Holocene. The recently observed accelerated ice loss of the Pine Island and Thwaites glaciers of the WAIS could also be considered as a consequence of this instability mechanism and could lead to an important contribution to sea-level rise in the future. The second mechanism that I will review is the binge-purge oscillation mechanism which could have caused the disintegration of the Laurentide ice sheet during the last glacial period. These oscillations could also explain future behaviour of the WAIS. Binge-purge oscillations are short periods of enhanced ice flow (purge phase) followed by periods of much slower flow (binge phase). These oscillations are usually explained by a thermal-gravitational instability which takes place when basal conditions change. I will focus my attention on the mathematical and physical conditions which can trigger this instability process, as well as on examples of such oscillations in the WAIS in the past. [less ▲]

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See detailGrazing practices, perception and expectations of Walloon dairy farmers
Lessire, Françoise ULg; Bernard, Maxime; Lioy, Rocco et al

in Högling, Mats; Bakken, Anne Kjersti; Hovstad, Knut Anders (Eds.) et al The multiple roles of grassland in the European bioecnomy (2016, September 04)

The role of grasslands as a C sink is generally accepted. It is considered that permanent grasslands allow annual C storage rates between 22 and 44 g C/m2/y (Soussana et al., 2010) thereby contributing to ... [more ▼]

The role of grasslands as a C sink is generally accepted. It is considered that permanent grasslands allow annual C storage rates between 22 and 44 g C/m2/y (Soussana et al., 2010) thereby contributing to the mitigation of greenhouse gas (GHG) emissions. Grassland preservation has several other advantages including a decrease in feeding costs (Dillon et al., 2005), a positive effect on cows’ health (e.g.a decrease in lameness) (Burow et al., 2011) and the provision of a positive image to consumers. Despite these arguments, grazing is decreasing in Europe and grasslands are disappearing. A better understanding of grazing practices and of farmers’ expectations could suggest ways of improving these practices and limiting grassland disappearance. As a result, Walloon dairy farmers were surveyed in December 2015 and the preliminary results are presented below. [less ▲]

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See detailBack on Track... in 3D
Marchal, Antoine ULg; Lejeune, Philippe ULg; De Bruyn, Nico

Poster (2016, September 04)

Ecological monitoring provides basic information on population status and distribution that is crucial for conservation, research and management strategies. Studies using tracks are controversial due to ... [more ▼]

Ecological monitoring provides basic information on population status and distribution that is crucial for conservation, research and management strategies. Studies using tracks are controversial due to past misuses tainted with subjectivity. Advances in photogrammetry literally add another dimension to the recording techniques, and geometric morphometrics provides an appropriate approach for the study of track shape variation. Tracks are back on track in conservation! [less ▲]

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See detailCo-producing evidence: Ethnographic inquiry of a "wild" search for causation
Duysens, Fanny ULg

Conference (2016, September 03)

Drawing on a multi-sited ethnography which explores the field of patients’ organizations (POs) concerned with genetic disorders within the Belgian context, this communication is interested in some ... [more ▼]

Drawing on a multi-sited ethnography which explores the field of patients’ organizations (POs) concerned with genetic disorders within the Belgian context, this communication is interested in some knowledge-related collaboration between POs and scientific and medical experts, or “wild research” projects (Callon & Rabeharisoa, 2003). Especially, it examines an informant's narrative of the "wild" search for causation of the disorder by which his family is concerned and the inherent forms and modalities of knowledge production, circulation and validation. While STS scholars have traditionally seen POs as epistemic communities, they currently point out an increasing engagement in such novel forms of collaboration over the last decades. This leads to the emergence of a certain “evidence-based activism” (EBA) among POs, characterized by a growing articulation of credential and more “experiential” knowledge to define common epistemologies of the conditions they are concerned with. The springs of this articulation remain to be explored. Thus, the aim is to flesh out the recent concept of EBA, to empirically question what it covers, and how new biomedical knowledge is generated by “evidence activists”. Rather than provoking “radical openings in technoscientific practice”, our observations show a continuous co-production of knowledge taking place within POs engaged in EBA. So, this paper will take stock of these transformations and envisage the affordances and blind spots for STS of the use of new concepts such as EBA. [less ▲]

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

Conference (2016, September 02)

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

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

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See detail“That’s only statistics”:Recording PPPs in national accounts
Piron, Damien ULg

Conference (2016, September 02)

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See detailLe potentiel des blogues et des réseaux numériques dans l'apprentissage d'une langue étrangère
Vintila, Elena-Georgiana ULg

Conference (2016, September 02)

We selected two French foreign language textbooks published in Romania under the Ministry of Education in 2004 and 2005 by the same publishing house and we will analyze the modality of presentation of ... [more ▼]

We selected two French foreign language textbooks published in Romania under the Ministry of Education in 2004 and 2005 by the same publishing house and we will analyze the modality of presentation of grammar points offered by textbooks and selected blogs. For this analysis, we will focus on: the appearance of textbooks, respectively blogs, the presentation of the grammar point set analysis, types and number of exercises. In addition, we will try to see what socio-cultural values ​​are highlighted by the authors and how bloggers alter through publications. [less ▲]

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See detailIntegrating Science and Technology into Sports: A Case Study of Sports Innovations in Belgium
Van Oudheusden, Michiel ULg; Van Hoyweghen, Ine

Conference (2016, September 01)

This paper explores the dynamic interplay between sports and innovation policies, research and development processes, and science-driven sports practices in Wallonia and Flanders (Belgium). Here, as in ... [more ▼]

This paper explores the dynamic interplay between sports and innovation policies, research and development processes, and science-driven sports practices in Wallonia and Flanders (Belgium). Here, as in other countries and regions, the aim of integrating science and technology into sports is now a leading sports policy principle and innovation strategy. Building on science and technology studies (STS) tools and methods (vision assessment, multi-site ethnography, foresight), the paper draws out the ethical, legal, and social issues (ELSI) induced by the use of new sciences and technologies in sports. These ELSI include the client-centered nature of sports science, which raises concerns about occupational control and athlete welfare, the uptake of genetic data in sports talent detection programs, and the challenges of coordinating "data-driven" and "intuitive" sports training approaches. It is argued that as sports are scientized and technologized, such ELSI demand to be addressed by sports innovators, governing bodies, and publics. By drawing critical attention to how sports are increasingly shaped by devices, data flows, and scientists, the paper states the case for bringing sports into STS and STS into sports. [less ▲]

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See detailHow to expand method by and for sensory: trials along and beside fieldwork
Vangeebergen, Thomas ULg

Conference (2016, September 01)

In a research with sensory analysts and flavourists, I tried other ways of interview (e.g. people auto-confrontations to their own registered activity) and other mediums to relate to the ethnographical ... [more ▼]

In a research with sensory analysts and flavourists, I tried other ways of interview (e.g. people auto-confrontations to their own registered activity) and other mediums to relate to the ethnographical work, as graphic novel or comics. [less ▲]

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