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See detailExploring a Mediterranean mesozooplankton 13 year time-series.
Fullgrabe, Lovina; Richir, Jonathan ULg; Batigny, Antoine et al

Poster (2016, December 16)

Zooplankton plays diverse crucial roles within the marine ecosystem and can also be used as bio- indicator of climate changes since it is very sensitive to environmental changes. Therefore it is essential ... [more ▼]

Zooplankton plays diverse crucial roles within the marine ecosystem and can also be used as bio- indicator of climate changes since it is very sensitive to environmental changes. Therefore it is essential to consider long-term plankton series. Given the analysis of plankton samples is time- consuming, it requires an effective and rapid analytical method. We have used in this work a supervised learning approach adapted for the semi-automatic classification of digital images of the mesozooplankton of the Bay of Calvi (Corsica, France) by using the Zoo/PhytoImage software. Together with a 11-years long zooplankton time-series, a set of nine environmental variables were monitored in order to identify controlling factors and determine whether the communities were sensitive to global environmental changes. The main components of the mesozooplankton community were characterized by both seasonal and inter-annual variability. Additionally, variation of holoplankton and meroplankton differentiated one from each other. The holoplanktonic community could be split into two subgroups according to its variation in function of the environment: cladocerans and appendicularians, and to a lesser extent, copepods on one hand, and cnidarians, chaetognathes and thaliaceans, on the other hand. Regarding inter-annual variation, one year (2007) showed particularly low production of total zooplankton which was also the case for all the different holoplanktonic taxa. Accounting for that phenomenon were identified some potentially underlying environmental factors. Finally, although water temperature increased significantly over the last years along with the frequency of marine heat wave events, no evident change in the global zooplankton composition was observed yet. [less ▲]

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See detail"'Unreadable' Texts: From the Metaphysical Detective Story to the Metacognitive Mystery Tale"
Dechene, Antoine ULg

Doctoral thesis (2016)

This dissertation aims at establishing the genealogy of a literary genre called the metacognitive mystery tale. Its main goal is to delineate a corpus of texts presenting "unreadable" mysteries which ... [more ▼]

This dissertation aims at establishing the genealogy of a literary genre called the metacognitive mystery tale. Its main goal is to delineate a corpus of texts presenting "unreadable" mysteries which, under the deceptively monolithic appearance of subverting "traditional" detective story conventions, offer a multiplicity of motifs – the overwhelming presence of chance, the unfulfilled quest for knowledge, the urban stroller lost in a labyrinthine text – that generate a vast array of epistemological and ontological uncertainties explored by the genre. The selected corpus, composed of some of the genre's most emblematic avatars as well as of less usual suspects, accounts for the specificity and heterogeneity of authors who, in different but related ways, have addressed a certain number of issues underlying the acquisition of knowledge. Following three major intertextual matrices based on the concepts of the "unreadable" city, the "dark" grotesque and the sublime, respectively, this project brings together texts by writers as diverse as Percy Bysshe Shelley, Edgar Allan Poe, Nathaniel Hawthorne, Herman Melville, Henry James, Horacio Quiroga, Jorge Luis Borges, Franz Kafka, Samuel Beckett, Paul Auster, Iain Sinclair and Roberto Bolaño under the banner of the metacognitive mystery tale. This approach represents an opportunity to gather canonical and barely academically studied works and provide new perspectives on stories dealing with the darker, more anxious aspects of investigations led by defective sleuths. [less ▲]

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See detailWho would want to live in there? A history of Posidonia oceanica detritus accumulations, the associated invertebrate community, and its food web…
Remy, François ULg; Michel, Loïc ULg; Darchambeau, François ULg et al

Conference (2016, December 16)

Most seagrasses are rarely consumed directly by herbivore organisms. The "detrital pathway" thus represents a potentially important way of transfer of the seagrasses production to the coastal food webs ... [more ▼]

Most seagrasses are rarely consumed directly by herbivore organisms. The "detrital pathway" thus represents a potentially important way of transfer of the seagrasses production to the coastal food webs. The case of Posidonia oceanica is particularly interesting since up to 90% of its foliar primary production may constitute extensive and highly dynamic exported litter accumulations. Preliminary studies concerning these detritus accumulations suggest that an abundant community of vagile macro invertebrates (size > 500μm) lives inside them. We characterized for the first time this community in an exhaustive way (multi-site, seasonal and multi-year study), we linked the observed density and diversity variations to environmental parameters, but also described the trophic web these invertebrates compose. We sampled an abundant (up to 5000 organisms/m²) community composed of 115 species. We showed that crustaceans were massively dominant, followed by annelids and mollusks, and that one single amphipod species Gammarella fucicola represented from 20 to 85% of the whole sampled community. Observed variations appeared to be mostly linked to litter oxygen water concentration in a very species specific way. Most species were linked to no measured environmental parameter at all, but several dominant species were demonstrated (observation and in situ experimentation) to be linked positively or negatively to litter oxygen concentration. The described food web was composed of more than 3 trophic levels, indicating the presence of a trophic web composed of primary consumers/detritivore species, of omnivore species, but also of first and second order predators, each level occupying a distinct isotopic niche. From a specific point of view, we highlighted several different feeding preferences, with SIAR mixing model runs indicating that some species feed mostly on detrital material, other species feed on a mixture of detrital and algal material, other species feed on both animal and vegetal material and finally predator species feed exclusively on animal material. The fact that P. oceanica detritus constituted a non-negligible food source for some dominant species confirmed the importance of this macrofauna community as a key transfer link of seagrass organic matter from P. oceanica to the coastal food webs. [less ▲]

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See detailBioaccumulation of trace metals in Mytilus galloprovincialis from the Algerian west coast
Rouabhi, Leila; Rouanne, Hassen Omar; Benkrama, Hadjer et al

Poster (2016, December 16)

Algeria has a 1622 km long coastal strip where a large proportion of the population and the main economic and industrial activities of the country are concentrated. Its coastal fringe therefore suffers ... [more ▼]

Algeria has a 1622 km long coastal strip where a large proportion of the population and the main economic and industrial activities of the country are concentrated. Its coastal fringe therefore suffers from various degradations. In particular, the Bay of Oran is housing industrial, commercial, fishing and recreational activities, where 80 % of domestic and industrial wastewaters are not purified before being discharged into the sea. Thus, the aim of the present work was to evaluate the degree of metallic contamination of coastal waters of western Algeria. Trace metals (Zn, Cu, Ni, Fe and Pb) were measured by atomic absorption spectroscopy in the dry soft tissues (gills and gonads) of the mussel Mytilus galloprovincialis Lamarck, 1819 collected during the four seasons of year 2010 in 2 sites: the highly polluted Oran harbor (S1) and Ain Defla (S2), a site distant enough from Oran and presumed little contaminated. Oran harbor was globally more contaminated than Ain Defla, especially for Fe, Zn and Ni. However, Pb levels were higher at Ain Defla with concentrations up to 3.35 ± 0.25 ppm in the gills. Metal concentrations differed between organs. Fe, Zn and Cu were more accumulated in gills (46.91 ± 1.60 ppm, 25.6 ± 1.07 ppm, 2.68 ± 0.50 ppm, respectively) compared to gonads (29.06 ± 1.07 ppm, 21.76 ± 1.46 ppm ppm, 1.44 ± 0.20 ppm, respectively). Each metal followed a seasonal trend, showing concentration peaks during winter and spring for gills and autumn for gonads. This study demonstrated the need to biomonitor the metallic contamination of Algerian coasts. But such monitoring surveys, relying on organisms, will require consensual sampling and analytical protocols to avoid hazardous conclusions due to tissue speciation and accumulation seasonality. [less ▲]

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See detailInstillation de surfactant chez le prématuré en respiration spontanée : méta-analyse
RIGO, Vincent ULg; LEFEBVRE, Caroline ULg; BROUX, Isabelle ULg

in Baud, Olivier; Saliba, Elie (Eds.) Congrès SFN-JFRN 2016, livre des communications (2016, December 15)

Justification: Lors du traitement par surfactant dit moins invasif (Less invasive surfactant therapy- LIST), le produit est instillé dans la trachée par un cathéter fin alors que l’enfant respire ... [more ▼]

Justification: Lors du traitement par surfactant dit moins invasif (Less invasive surfactant therapy- LIST), le produit est instillé dans la trachée par un cathéter fin alors que l’enfant respire spontanément sous CPAP. Différentes études ont donné des résultats variables mais encourageants. L’objectif de cette méta-analyse est de comparer le devenir respiratoire des prématurés traités par LIST avec celui de ceux traités par administration de surfactant par un tube endotrachéal. Méthodes : les études randomisées contrôlées (ERC) sont recherchées dans les bases de données et dans les références d’articles pertinents. Les devenirs respiratoires (dysplasie broncho-pulmonaire (DBP), décès ou DBP, échec précoce de CPAP, nécessité de ventilation invasive) et les morbidités classiques sont reprises de ces études. Pour chaque morbidité, le risque relatif (RR) des données mutualisées est calculé avec une analyse de Mantel-Haenszel à modèle d’effet aléatoire. Le RR est également calculé pour des sous-groupes établis selon l’intervention contrôle. Résultats : six ERC évaluent le LIST : 4 le comparent à l’INSURE (Intubation-Surfactant-Extubation), et les 2 autres à l’intubation (immédiate ou après maintient en CPAP) avec surfactant. Les méthodes LIST diminuent les risques de DBP (RR= 0,71 (0,52-0,99) ; nombre nécessaire à traiter NNT= 21), et de décès ou DBP (RR= 0,7 (0,58- 0,94) ; NNT= 15). L’échec précoce de CPAP et le recours à la ventilation invasive sont également réduits (RR= 0,67 (0,53-0,84) ; NNT= 8 et RR= 0,69 (0,53- 0,88) ; NNT= 6). Comparé à l’INSURE, le LIST diminue le risque combiné de décès ou DBP (RR= 0,63 (0,44-0,92) ; NNT= 11), et d’échec précoce de CPAP (RR=0,71 (0,53-0,96) ; NNT= 11). Les autres morbidités néonatales classiques sont similaires pour les différents groupes. Conclusions : une stratégie d’administration dite moins invasive de surfactant diminue les risques de morbidité respiratoire à moyen terme (DBP, décès ou DBP) et le recours à la ventilation invasive. Cette approche semble sure mais les données de suivi à long terme sont insuffisantes. [less ▲]

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See detailCathéters pour instillation moins invasive de SURFACTANT : une étude de simulation
RIGO, Vincent ULg; Debauche, Christian; Maton, Pierre et al

in Baud, Olivier; Saliba, Elie (Eds.) Congrès JFN-JFRN 2016, livre des communications (2016, December 15)

Introduction et objectifs : l’instillation trachéale de surfactant par un cathéter fin (Less invasive surfactant therapy- LIST) chez le prématuré sous CPAP permet de diminuer la morbidité respiratoire ... [more ▼]

Introduction et objectifs : l’instillation trachéale de surfactant par un cathéter fin (Less invasive surfactant therapy- LIST) chez le prématuré sous CPAP permet de diminuer la morbidité respiratoire. Plusieurs cathéters sont décrits à cette fin : une sonde oro-gastrique insérée avec (LISA-Köln, K) ou sans pince de Maggil (Take Care- Ankara, A), un cathéter veineux de 13 cm (MIST- Hobart, H), un cathéter d’angiographie de 30 cm (Stockholm, S) ou un cathéter ombilical fixé à un stylet d’intubation utilisé localement (Liège, L). L’objectif de l’étude est d’évaluer l’efficacité de ces techniques en prenant l’INSURE (Intubation-Surfactant-Extubation) comme référence. Intervention : 20 néonatologues travaillant dans 4 services ayant des stratégies d’administration du surfactant différentes ont participé. Ils ont simulé ces 6 techniques sur deux têtes d’intubation de difficulté croissante. L’efficacité de l’intervention est évaluée par le taux d’échec et la durée de procédure mesurée sur vidéo. Chaque intervenant apprécie la facilité d’utilisation sur une échelle de 1 à 9 (Difficile> facile). Résultats : Pour le premier modèle, les durées médianes de procédure pour Köln et Ankara sont allongées [K: 21s (IQR 17-24); A: 23s (15-42); H: 10s (8-16); S: 12s (10-22); L (10-20); INSURE: 14s (11-21); p<.0001]. Pour le second modèle, seul Liège permet une durée de procédure similaire à l’INSURE [K: 32s (25-44); A: 39s (27-95); H: 34s (27-46); S: 37s (29-42); L: 24s (15-35); INSURE: 24s (17-32); p<.002]. Les taux d’échec des méthodes LIST sont similaires entre eux (de 3 à 8/ 40 essais), mais supérieurs à celui de l’INSURE (0/40). Köln et Ankara sont considérés comme plus difficiles [scores de facilité : K: 5 (4-6); A: 3 (2-4); H: 6,5 (6-7); S: 7 (4-8); L: 8 (6,5-8); INSURE: 7 (6-8); p<.001]. Conclusions : les cathéters plus rigides sont plus efficaces et perçus comme plus simples d’utilisation. L’insertion d’un cathéter guidé et incurvé pourrait être plus rapide dans les cas difficiles. [less ▲]

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See detailAjustement des marqueurs d’insertion des tubes endotrachéaux selon l’âge gestationnel.
RIGO, Vincent ULg; Fayoux, Pierre

in Baud, Olivier; Saliba, Elie (Eds.) Congrès SFN-JFRN 2016, livre des communications (2016, December 15)

Introduction et objectifs: le positionnement adéquat d’un tube endotrachéal (TET) peut être difficile en raison de la marge de manœuvre limitée associée aux faibles distances laryngo-trachéales du ... [more ▼]

Introduction et objectifs: le positionnement adéquat d’un tube endotrachéal (TET) peut être difficile en raison de la marge de manœuvre limitée associée aux faibles distances laryngo-trachéales du prématuré. Les marqueurs distaux censés faciliter l’évaluation de ce positionnement ne sont pas standardisés entre les fabriquants, et le marquage généralement unique par taille de tube ne tient pas compte de la croissance associée à l’âge gestationnel. L’objectif de l’étude est de décrire les distances entre les cordes vocales (CV) et la moitié de la trachée en fonction de l’âge gestationnel et proposer des nouveaux marquages adaptés. Méthodes : la moitié de la longueur de la trachée ajoutée à la hauteur de la lame postérieure du cricoïde permet d’estimer la distance entre les CV et la moitié de la trachée (CV-MiTr). Ces longueurs sont issues à postériori d’une base de données prospective reprenant les distances détaillées du larynx et de la trachée mesurées lors d’autopsies de fœtus et nouveau-nés exempts de malformation des voies respiratoires (Fayoux et coll., Journal of anatomy 2008). Une corrélation est établie avec l’âge gestationnel. Résultats : les données proviennent de 121 patients. Il existe une corrélation linéaire entre la distance CV-MiTr et l’AG (r=0,91; y=2,6043+0,6275x; p<.0001). Des marqueurs d’insertion positionnés à 17,7; 18,9; 20,8; 22,7; 24,6 et 26,4 mm correspondraient à des AG de 24, 26, 29, 32, 35 et 38 semaines respectivement. Ils pourraient être indiqués par des lignes de couleurs contrastées. Conclusion : la relation linéaire entre la distance CV-mi-trachée et l’AG donne l’opportunité de revoir les marqueurs d’insertion des tubes endotrachéaux pour les patients les plus petits. Ces nouveaux marqueurs devraient être comparés cliniquement à ceux actuellement en usage avant d’être généralisés. [less ▲]

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See detailApplication des techniques de photogrammétrie par drone à la caractérisation des ressources forestières
Lisein, Jonathan ULg

Doctoral thesis (2016)

Une gestion raisonnée et multifonctionnelle des forêts n’est possible qu’avec une description à jour de l’état de la ressource naturelle. Les inventaires forestiers traditionnels, réalisés sur le terrain ... [more ▼]

Une gestion raisonnée et multifonctionnelle des forêts n’est possible qu’avec une description à jour de l’état de la ressource naturelle. Les inventaires forestiers traditionnels, réalisés sur le terrain, sont couteux et ne couvrent qu’un échantillonnage de la surface boisée. L’essor des drones civils pour la cartographie a initié une révolution dans le domaine de la télédétection environnementale. La polyvalence et la diversité des systèmes drones sont une aubaine pour la foresterie de précision. Ceux-ci sont utilisés pour la réalisation de cartographie très fine des habitats naturels avec une résolution temporelle et spatiale sans précédent. Nous explorons les possibilités d’utilisation de mini-drones pour la caractérisation quantitative et qualitative de la ressource forestière. Nous nous intéressons en particulier à l’estimation de la hauteur des arbres et à la caractérisation de la composition spécifique au sein de peuplements forestiers. La hauteur de la canopée est une variable dendrométrique de première importance : elle est un bon indicateur du stade de développement des peuplements et intervient notamment dans les estimations de biomasse ou de niveau de productivité. La composition spécifique est une information essentielle en regard des principales fonctions que remplit la forêt (conservation, production, récréation, etc). Nous avons comparé l’estimation de la hauteur des peuplements à partir de mesures LiDAR et celle obtenue par photogrammétrie. Bien que permettant une mesure de hauteur individuelle avec une incertitude de l’ordre de 1.04 m (RMSE) en feuillus, la photogrammétrie par drone sur des zones forestières est systématiquement moins précise que les mesures par LiDAR (RMSE de 0.83 m). Ces résultats sont cependant prometteurs, étant donné que la mesure sur terrain de la hauteur totale des arbres est également sujette à une importante imprécision. De plus, la grande flexibilité que confère les petits drones permet d’acquérir, au moment propice du stade de végétation, et l’information de relief de la canopée, et l’information spectrale. La période de fin de feuillaison, au début du mois de juin, s’est avérée le moment le plus propice à une discrimination automatique de cinq groupes d’essences feuillues (le chênes pédonculé, les bouleaux, l’érable sycomore, le frêne commun et les peupliers). Une erreur globale de classification des houppiers de 16% est obtenue avec des acquisitions monotemporelles, alors que l’utilisation d’images acquises à différentes dates permet encore d’améliorer cette classification (erreur globale de classification de 9% pour la meilleure combinaison de 3 dates). Les contraintes de la législation régissant l’utilisation des aéronefs sans pilote à bord restreignent le champs d’action des drones civils. Ainsi, afin d’assurer une sécurité pour tous les usagers de l’espace aérien, les opérations avec un drone sont limitées sous un seuil d’altitude et à une distance maximale du télépilote, ce qui ne permet pas une utilisation optimale de cette technologie pour la couverture de grands domaines forestiers (plusieurs milliers d’hectares). De plus, d’autres outils de télédétection utilisés en foresterie, tels que le LiDAR et l’imagerie satellite et aéroportée, sont plus compétitifs que les drones dès qu’il s’agit de couvrir de grandes surfaces (plusieurs milliers d’hectacre). C’est pourquoi nous pensons que les drones resterons un outils d’analyse de petites surfaces (dizaines voire centaines d’hectares), plus utiles à des fins de recherches scientifiques qu’à une utilisation en gestion forestière. [less ▲]

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See detailVibrio spp chez l’Homme - Vibrio spp bij de mens
MELIN, Pierrette ULg; SACHELI, Rosalie ULg

in POLET, Marie (Ed.) Vibrio spp dans l’alimentation et chez l’Homme - Formation (2016, December 15)

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See detail11 interventions dans la presse écrite et radio au sujet des techno-pédagogies, du 22 mai 2013 jusqu'au 16 janvier 2017
Verpoorten, Dominique ULg

Article for general public (2016)

Ces interventions témoignent du suivi appréciatif et critique des initiatives en matière de techno-pédagogie pour l'enseignement supérieur.

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See detailIntegrating Non-Collocated Well and Geophysical Data to Capture Lithological Heterogeneity at a Managed Aquifer Recharge and Recovery Site
Gottschalk, Ian; Hermans, Thomas ULg; Caers, Jef et al

Poster (2016, December 15)

Aquifer recharge and recovery (ARR) is the process of enhancing natural groundwater resources and recovering water for later use by constructing engineered conveyances. Insufficient understanding of ... [more ▼]

Aquifer recharge and recovery (ARR) is the process of enhancing natural groundwater resources and recovering water for later use by constructing engineered conveyances. Insufficient understanding of lithological heterogeneity at ARR sites often hinders attempts to predict where and how quickly infiltrating water will flow in the subsurface, which can adversely affect the quality and quantity of available water in the ARR site. In this study, we explored the use of electrical resistivity tomography (ERT) to assist in characterizing lithological heterogeneity at an ARR site, so as to incorporate it into a flow and contaminant transport model. In this case, we had non-collocated well core log data and ERT data from a full-scale ARR basin. We compared three independent methods for producing conditional lithology-resistivity probability distributions: 1) a search template to relate the nearest logged well lithologies with ERT resistivity panels, given search criteria; 2) a maximum likelihood estimation (MLE) to match bimodal normal distributions to the histogram of each ERT line; and 3) variogram-based lithology indicator simulations constrained to well data. Each approach leverages Bayes’ Rule to estimate lithology probability given electrical resistivity. The simplest approach (method 1) yields an erroneous conditional probability function where sand dominates the conditional probability at nearly all resistivities, due in part to the strong presence of sand in the wells nearest the ERT lines. The approaches using MLE and lithology simulations (methods 2 and 3) produce similar, more realistic lithofacies probability functions. The range of resistivities where clay and sand overlap differs between methods 2 and 3: ranging between 100 and 200 ohm-m for method 2, and between 30 and 50 ohm-m for the method 3. These differences affect the posterior lithology distributions in multiple point geostatistical (MPS) simulations, and in turn, predictions of flow from models which integrate these results. To test the models, we can compare measured breakthrough times of recharged water at the site to groundwater flow simulation results using the lithofacies models created by each method. The methods described here can inform the integration of non-collocated geophysical data into a variety of applications. [less ▲]

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See detailThe complex behavior of the satellite footprints at Jupiter: the result of universal processes?
Bonfond, Bertrand ULg; Grodent, Denis ULg; Badman, Sarah V. et al

Poster (2016, December 14)

At Jupiter, some auroral emissions are directly related to the electromagnetic interaction between the moons Io, Europa and Ganymede on one hand and the rapidly rotating magnetospheric plasma on the other ... [more ▼]

At Jupiter, some auroral emissions are directly related to the electromagnetic interaction between the moons Io, Europa and Ganymede on one hand and the rapidly rotating magnetospheric plasma on the other hand. Out of the three, the Io footprint is the brightest and the most studied. Present in each hemisphere, it is made of at least three different spots and an extended trailing tail. The variability of the brightness of the spots as well as their relative location has been tentatively explained with a combination of Alfvén waves’ partial reflections on density gradients and bi-directional electron acceleration at high latitude. Should this scenario be correct, then the other footprints should also show the same behavior. Here we show that all footprints are, at least occasionally, made of several spots and they all display a tail. We also show that these spots share many characteristics with those of the Io footprint (i.e. some significant variability on timescales of 2-3 minutes). Additionally, we present some Monte-Carlo simulations indicating that the tails are also due to Alfvén waves electron acceleration rather than quasi-static electron acceleration. Even if some details still need clarification, these observations strengthen the scenario proposed for the Io footprint and thus indicate that these processes are universal. In addition, we will present some early results from Juno-UVS concerning the location and morphology of the footprints during the first low-altitude observations of the polar aurorae. These observations, carried out in previously unexplored longitude ranges, should either confirm or contradict our understanding of the footprints. [less ▲]

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See detailJupiter’s auroras during the Juno approach phase as observed by the Hubble Space Telescope
Nichols, Jonathan D; Clarke, John T; Orton, Glennn S et al

Conference (2016, December 13)

We present movies of the Hubble Space Telescope (HST) observations of Jupiter’s FUV auroras observed during the Juno approach phase and first capture orbit, and compare with Juno observations of the ... [more ▼]

We present movies of the Hubble Space Telescope (HST) observations of Jupiter’s FUV auroras observed during the Juno approach phase and first capture orbit, and compare with Juno observations of the interplanetary medium near Jupiter and inside the magnetosphere. Jupiter’s FUV auroras indicate the nature of the dynamic processes occurring in Jupiter’s magnetosphere, and the approach phase provided a unique opportunity to obtain a full set of interplanetary data near to Jupiter at the time of a program of HST observations, along with the first simultaneous with Juno observations inside the magnetosphere. The overall goal was to determine the nature of the solar wind effect on Jupiter’s magnetosphere. HST observations were obtained with typically 1 orbit per day over three intervals: 16 May – 7 June, 22-30 June and 11-18 July, i.e. while Juno was in the solar wind, around the bow shock and magnetosphere crossings, and in the mid-latitude middle-outer magnetospheres. We show that these intervals are characterised by particularly dynamic polar auroras, and significant variations in the auroral power output caused by e.g. dawn storms, intense main emission and poleward forms. We compare the variation of these features with Juno observations of interplanetary compression regions and the magnetospheric environment during the intervals of these observations. [less ▲]

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See detailSearch for low-latitude atmospheric hydrocarbon variations on Jupiter from Juno-UVS measurements
Hue, Vincent; Gladstone, Randy; Greathouse, Thomas et al

Conference (2016, December 13)

The Juno mission offers the opportunity to study Jupiter, from its inner structure, up to its magnetospheric environment. Juno was launched on August 2011 and its Jupiter orbit insertion (JOI) occurred on ... [more ▼]

The Juno mission offers the opportunity to study Jupiter, from its inner structure, up to its magnetospheric environment. Juno was launched on August 2011 and its Jupiter orbit insertion (JOI) occurred on July 4th 2016. The nominal Juno mission involves 35 science polar-orbits of 14-days period, with perijove and apojove distances located at 0.06 Rj and 45 Rj, respectively. Juno-UVS is a UV spectrograph with a bandpass of 70<λ<205 nm, designed to characterize Jupiter UV emissions. One of the main additions of UVS compared to its predecessors (New Horizons- and Rosetta- Alice, LRO-LAMP) is a 2.54 mm tantalum shielding, to protect it from the harsh radiation environment at Jupiter, and a scan mirror, to allow for targeting specific auroral and atmospheric features at +/- 30˚ perpendicular to the Juno spin plane. It will provide new constraints on Jupiter’s auroral morphology, spectral features, and vertical structure, while providing remote-sensing constraints for the onboard waves and particle instruments. It will also be used to probe upper-atmospheric composition through absorption features found in the UV spectra using reflected solar UV radiation. For example, stratospheric hydrocarbons such as C2H2 and C2H6 are known to absorb significantly in the 150-180 nm regions, and these absorption features can be used to determine their abundances. We will present our search for the spectroscopic features seen in Jupiter’s reflected sunlight during the first perijove. [less ▲]

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See detailInitial observations of Jupiter’s aurora from Juno’s Ultraviolet Spectrograph (Juno-UVS)
Gladstone, Randy; Versteeg; Greathouse, Thomas et al

Conference (2016, December 13)

Juno-UVS is an imaging spectrograph with a bandpass of 70<λ<205 nm. This wavelength range includes important far-ultraviolet (FUV) emissions from the H2 bands and the H Lyman series which are produced in ... [more ▼]

Juno-UVS is an imaging spectrograph with a bandpass of 70<λ<205 nm. This wavelength range includes important far-ultraviolet (FUV) emissions from the H2 bands and the H Lyman series which are produced in Jupiter’s auroras, and also the absorption signatures of aurorally-produced hydrocarbons. The Juno-UVS instrument telescope has a 4x4 cm2 input aperture and uses an off-axis parabolic primary mirror. A flat scan mirror situated near the entrance of the telescope is used to observe at up to ±30° perpendicular to the Juno spin plane. The light is focused onto the spectrograph entrance slit, which has a “dog-bone” shape, with three sections of 2.55°x0.2°, 2.0°x0.025°, and 2.55°x0.2° (as projected onto the sky). Light entering the slit is dispersed by a toroidal grating which focuses FUV light onto a curved microchannel plate (MCP) cross delay line (XDL) detector with a solar blind UV-sensitive CsI photocathode. The two mirrors and the grating are coated with MgF2 to improve FUV reflectivity. Tantalum surrounds the spectrograph assembly to shield the detector and its electronics from high-energy electrons. All other electronics are located in Juno’s spacecraft vault, including redundant low-voltage and high-voltage power supplies, command and data handling electronics, heater/actuator electronics, scan mirror electronics, and event processing electronics. The purpose of Juno-UVS is to remotely sense Jupiter’s auroral morphology and brightness to provide context for in situ measurements by Juno’s particle instruments. Here we present the first near-Jupiter results from the UVS instrument following measurements made during PJ1, Juno’s first perijove pass with its instruments powered on and taking data. [less ▲]

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See detailLimited Impact of Imatinib in a Murine Model of Sclerodermatouc Chronic Graft-versus-Host Disease
Belle, Ludovic; Fransolet, Gilles ULg; Somja, Joan ULg et al

in PLoS ONE (2016)

Background Sclerodermatous chronic Graft-versus-Host Disease (scl-cGVHD) is one of the most severe form of cGVHD. The Platelet-derived Grotwth Factor (PDGF) and the Transforming Growth Factor-β (TGF-β ... [more ▼]

Background Sclerodermatous chronic Graft-versus-Host Disease (scl-cGVHD) is one of the most severe form of cGVHD. The Platelet-derived Grotwth Factor (PDGF) and the Transforming Growth Factor-β (TGF-β) play a significant role in the fibrosing process occurring in scl-cGVHD. This prompted us to assess the impact of the PDGF-r and c-Abl tyrosine kinase inhibitor imatinib on scl-cGVHD. Methods To assess the impact of imatinib on T cell subset proliferation in vivo, Balb/cJ recipient mice were lethally (7 Gy) irradiated and then injected with 10x106 bone marrow cells from B10.D2 mice on day 0. Fourteen days later, 70x106 carboxyfluorescein succinimidyl ester (CFSE)- labeled splenocytes from B10.D2 mice were infused and imatinib or sterile water was administered for 5 days. To induce severe scl-cGVHD, Balb/cJ mice were injected i.v. with 10.106 bone marrow cells and 70.106 splenocytes from B10.D2 donor mice after 7 Gy irradiation. Mice were then given sterile water or imatinib from day +7 after transplantation to the end of the experiment (day +52). Results Imatinib decreased the proliferation of total T cells (P = 0.02), CD8+ T cells (P = 0.01), and of regulatory T cells (Tregs) (P = 0.02) in the spleen. In the severe scl-cGVHD model, imatinib- treated mice had significantly lower levels of PDGF-r phosphorylation than control mice on day 29 after transplantation (P = 0.008). However, scl-cGVHD scores were similar between vehicle- and imatinib-treated mice during the whole experiment, while there was a suggestion for less weight loss in imatinib-treated mice that reached statistical significance at day +52 following transplantation (P = 0.02). [less ▲]

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See detailUnreinforced clay masonry structures: advanced characterisation of the seismic behaviour including acoustic issues
Mordant, Christophe ULg

Doctoral thesis (2016)

Unreinforced masonry (URM) is traditionally used in North-Western Europe as load- bearing solution for low- to mid-rise buildings. These regions are characterised by a low- to-moderate seismicity. Hence ... [more ▼]

Unreinforced masonry (URM) is traditionally used in North-Western Europe as load- bearing solution for low- to mid-rise buildings. These regions are characterised by a low- to-moderate seismicity. Hence, the earthquake action has to be considered in the structural design. An adequate consideration of the seismic action requires to properly understand how the URM structures behave under this speci c dynamic action and investigations are still needed in that eld. The in uence of openings and walls perpendicular to the seismic action are two main issues. Moreover, the seismic response of these structures is a ected by technical solutions developed to face the demand in terms of building physics performances. Even though, these solutions are not yet integrated in current standards. This thesis aims at improving the understanding of the seismic behaviour of URM struc- tures using a particular type of masonry bonding, for constructional e ciency purposes. Hollow clay blocks are assembled by thin-bed layered glue-mortar joints and a tongue-and- groove system for the head joints. The consequences of speci c details such as an opening, a perpendicular wall or soundproo ng rubber layers are also studied. Four experimental campaigns are presented. Fourteen URM sub-structures including speci c details are tested in static-cyclic and dynamic conditions. Details of the set-up, instrumentation layout and testing procedures are given. Processing of the data is then performed and conclusions are drawn. Regarding the shake table tests, a general rocking be- haviour strongly dependent on the length of the wall and the presence of rubber, is observed. Recommendations for the consideration of soundproo ng devices and for the openings are proposed. The contribution to the strength of perpendicular walls is also highlighted. Based on the dynamic characterisation of the specimens, equivalent mechanical properties are calibrated thanks to the frequency equation, derived from the Timoshenko beam theory. Two sets of boundary conditions are de ned to t the testing con gurations. The relevance of this theory is assessed and the importance of each term of the equation is discussed. In order to extend the results to complete buildings, the tested specimens are modelled in a software implementing an equivalent frame at the macro-scale. A multi-linear material law is calibrated based on a single specimen chosen as reference, in order to reproduce the experimental force-displacement curve. This law is then used for all specimens built in the same masonry type, independently of their geometry. A good approximation is obtained, even if the consideration of perpendicular walls could be improved. The shear capacity of non-rectangular URM walls depends on the compressive length. Its exact expression is thus developed with due consideration of the perpendicular section. Non linearities are observed due to the presence of the perpendicular section and simpli - cations are made for hand calculations. Both the use of the exact and simpli ed expressions in the assessment of the shear resistance provide results similar to the experiments. Finally, the modelling of the rocking motion is investigated. The walls without sound- proo ng devices are modelled following di erent existing models and their predictions are compared with experimental measurements, showing that masonry cannot be assumed as rigid. A main issue is the handling of the transition with impacts. A new model including two rigid blocks and exible and viscous layers is developed to reproduce the rocking behaviour of walls including rubber layers. In presence of rubber, the URM wall can be considered as rigid and model predictions satisfactorily corroborate the experimental measurements. [less ▲]

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See detailLa faisabilité et l'efficacité du traitement assisté par diacétylmorphine en Belgique
Demaret, Isabelle ULg

Scientific conference (2016, December 12)

Objective The aim of our research was to assess the feasibility and efficacy of a treatment assisted by diacetylmorphine in Liège. This treatment is offered to persons dependent on heroin who pursue ... [more ▼]

Objective The aim of our research was to assess the feasibility and efficacy of a treatment assisted by diacetylmorphine in Liège. This treatment is offered to persons dependent on heroin who pursue street heroin use despite existing treatments. Methods Data were collected in a pilot project of Treatment Assisted by Diacetylmorphine (TADAM), which took place in Liège from 2007 to 2013. The heart of this project is a randomised controlled trial comparing a diacetylmorphine treatment – limited to 12 months – with existing methadone treatments. A participant was responder if he/she showed improvement on the level of street heroin use, health or criminal involvement. Other researches (mainly based on interviews) were added in order to understand interactions between the trial and its actors: heroin users (included or not-included), neighbours of the DAM centre, the staff of the DAM centre and staff of other institutions who worked with our target group in Liège. Results With the help of the centres, partners of the trial, 74 participants (of the 200 planned) were included and randomised: 36 in the experimental group and 38 in the control group. These participants were dependent on heroin for 20 years on average and had already tried 9 treatments for their addiction(s). At the end of the trial, the number of responders in the experimental group was greater but not significantly than in the control group (p=0.35). However, participants in the experimental group showed greater improvement than in the control group, on the level of street heroin use (p=0.0011) and physical (p=0.043) or mental (p=0.035) health. During the follow-up study, three months after the end of the 12 months of treatment, street heroin use in the experimental group had significantly increased (p=0.0052) and the difference with the control group was no longer significant (p=0.55). Discussion Participants included in the trial were, as expected, persons severely dependent on street heroin, who could not find a solution to their addiction with the existing treatments. Participants in the experimental group decreased significantly their street heroin use. However, in our follow-up study, street heroin use increased significantly in the experimental group 3 months after the end of the diacetylmorphine treatment. In the foreign studies, diacetylmorphine treatment showed greater efficacy compared to methadone treatment for this target group and the improvement was sustained after the trial even when the treatment was stopped, but not when the end of treatment was forced against the will of the patient. Nevertheless, our research showed the feasibility of a diacetylmorphine treatment in Liège and its acceptance by the actors involved in the trial. Conclusion Diacetylmorphine treatment is feasible in Belgium. In foreign studies, it showed more efficacy than methadone treatment and benefits gained with this approach were maintained during years. But these benefits disappear when the end of treatment is forced, against the will of the patient. [less ▲]

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See detailLe futur du travail à l'ère digitale
Delvenne, Pierre ULg

Conference given outside the academic context (2016)

Cette présentation aborde de manière critique les changements qui s'opèrent dans le monde du travail sous l'impulsion des technologies digitales (robotisation, automatisation, objets connectés, etc). Dans ... [more ▼]

Cette présentation aborde de manière critique les changements qui s'opèrent dans le monde du travail sous l'impulsion des technologies digitales (robotisation, automatisation, objets connectés, etc). Dans une perspective interdisciplinaire, à l'aide de nombreux exemples, elle aborde les interactions entre la technologie, l'économie, la société et le politique et examine les conditions d'émergences et les conséquences des changements en cours sur le monde du travail. Elle invite à prendre urgemment la pleine mesure de la rupture qui s'opère avec la digitalisation et formule des recommandations concrètes. [less ▲]

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