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See detailEOF analysis of long-term reconstructed AVHRR Pathfinder SST in the South China Sea
Huynh, Thi Hong Ngu ULg; Alvera Azcarate, Aïda ULg; Barth, Alexander ULg et al

Poster (2014, May 02)

Sea surface temperature (SST) is one of the key variables often used to investigate ocean dynamics, ocean-atmosphere interaction, and climate change. For recent decades, the AVHRR Pathfinder SST, measured ... [more ▼]

Sea surface temperature (SST) is one of the key variables often used to investigate ocean dynamics, ocean-atmosphere interaction, and climate change. For recent decades, the AVHRR Pathfinder SST, measured by infrared sensors, has been widely used because of its high resolution and long time-series. The disadvantage of the AVHRR Pathfinder SST is high percentage of missing data due to cloud coverage. This becomes more serious in the South China Sea (SCS) because it is located in the tropical region, frequently covered by clouds. In this study, we used the Data INterpolating Empirical Orthogonal Functions (DINEOF) method to reconstruct daily night-time 4 km AVHRR Pathfinder SST spanning from 1989 to 2009 for the whole SCS. In order to better understand the spatial and temporal variability of the SCS SST, an EOF analysis of the reconstructed field is performed in association with surface wind. The first SST mode, accounting for 69% of the variance, presents the cooling (warming) of the basin due to the solar inclination through seasons, water exchange, topography, and monsoon-induced cyclonic circulation. The second SST mode, explaining 24.8% of the variance, shows the advection of cold and warm water from two opposite directions along the southwest-northeast diagonal of the basin. The second SST mode is affected by the atmospheric anticyclone (cyclone) located over the Philippine Sea. Comparing both SST modes with Nino3.0 index, it shows that the interannual variability of the SCS SST is influenced by the moderate and strong ENSO events with a lag of 5-6 months. Moreover, the analysis of the high-resolution reconstructed dataset reveals some oceanic features that could not be captured in previous EOF analyses. [less ▲]

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See detailEffect of the RE (RE = Eu, Er) doping on the structural and textural properties of mesoporous TiO2 thin films obtained by evaporation induced self-assembly method
Borlaf, Mario; Caes, Sébastien ULg; Dewalque, Jennifer ULg et al

in Thin Solid Films (2014), 558

Polymeric sol–gel route has been used for the preparation of TiO2 and RE2O3–TiO2 (RE = Eu, Er) mesoporous thin films by evaporation induced self-assembly method using Si (100) as a substrate. The ... [more ▼]

Polymeric sol–gel route has been used for the preparation of TiO2 and RE2O3–TiO2 (RE = Eu, Er) mesoporous thin films by evaporation induced self-assembly method using Si (100) as a substrate. The influence of the relative humidity (RH) on the preparation of the film has been studied being necessary to work under 40% RH in order to obtain homogeneous and transparent thin films. The films were annealed at different temperatures until 900 °C/1 h and the anatase crystallization and its crystal size evolution were followed by low angle X-ray diffraction. Neither the anatase–rutile transition nor the formation of other compounds was observed in the studied temperature range. Ellipsoporosimetry studies demonstrated that the thickness of the thin films did not change after calcination at 500 °C, the porosity was constant until 700 °C, the pore size increased and the specific surface area decreased with temperature. Moreover, the effect of the doping with Er3 + and Eu3 + was studied and a clear inhibition of the crystal growth and the sintering process was detected (by transmission electron and atomic force microscopy) when the doped films are compared with the undoped ones. Finally, Eu3 + and Er3 + f–f transitions were detected by PL measurements. [less ▲]

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See detailUsing the Multiple SEA Method to Synthesize Pt/Carbon Xerogel Electrocatalysts for PEMFC Applications
Zubiaur, Anthony ULg; Chatenet, Marian; Maillard, Frédéric et al

in Fuel Cells - From Fundamentals to Systems (2014), 14(3), 343-349

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See detailEffect of metal nanoparticles encapsulated in porous silica on the biphenyl biodegradation by Rhodococcus erythropolis T902.1
Wannoussa, Wissal ULg; Hiligsmann, Serge ULg; Heinrichs, Benoît ULg et al

Poster (2014, May 01)

Biphenyl is stable and highly hydrophobic, thus having a low availability for degrading microorganisms, which need an aqueous environment for their growth. As a consequence, bioremediation processes are ... [more ▼]

Biphenyl is stable and highly hydrophobic, thus having a low availability for degrading microorganisms, which need an aqueous environment for their growth. As a consequence, bioremediation processes are very limited. However, a few studies showed that using a low metal concentration accelerates the biodegradation of pollutants (Yeom and Yoo1997). Nanoparticles are considered as a new generation of compounds to improve environmental remediation and biological processes (Beckers et al. 2013; Zhang 2003). This paper investigated the enhancement effect of nanometre-sized metallic Cu, Ag, Pd or Co, on the biphenyl biodegradation by Rhodococcus erythropolis T902.1. Have been synthesized by a sol–gel process (Lambert et al. 2004). These nanoparticles (NP) of about 2–3 nm were encapsulated in porous silica (SiO2) and were added at low concentration (10-4M) in the M284 minimal medium with 500 ppm biphenyl as source of carbon and energy. The cultures containing Pd or Co produced 30% more biphenyl degraded with a higher Rhodococcus growth than those without NP (positive control) or with silica particles only. On the contrary, the presence of 10-4 M Cu or Ag nanoparticles showed an inhibitory effect on bacterial growth and biphenyl degradation compared to the positive. [less ▲]

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See detailInternet facilite-t-il un apprentissage de plus en plus auto-déterminé ? Illustrations et réflexions.
Poumay, Marianne ULg

Conference (2014, May 01)

Après avoir introduit le thème du contrôle par l’étudiant de son propre apprentissage, la conférence illustrera des situations d’apprentissage et d’évaluation (bien sûr faisant usage d’Internet) qui ... [more ▼]

Après avoir introduit le thème du contrôle par l’étudiant de son propre apprentissage, la conférence illustrera des situations d’apprentissage et d’évaluation (bien sûr faisant usage d’Internet) qui poussent l’étudiant à faire des choix et qui, en corollaire, aboutissent à faire valider par les enseignants le résultat de trajectoires riches et différenciées. Rassembler des preuves de son développement de compétences, planifier son inscription dans une série de MOOCs ou son travail en ligne suite à un test diagnostique sont autant d’actions qui responsabilisent l’étudiant quant à sa propre formation. Mais l’apprentissage autodéterminé est-il à la portée de tous les étudiants ? [less ▲]

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See detailApproche systémique de l’intégration des TIC dans l’éducation : enjeux, actions et perspectives à l’horizon 2020
Denis, Brigitte ULg

Conference (2014, May 01)

En Belgique francophone, diverses initiatives ont vu le jour durant ces quinze dernières années dans le but de développer un usage réfléchi des TIC en éducation. Parmi celles-ci épinglons les « Plans TIC ... [more ▼]

En Belgique francophone, diverses initiatives ont vu le jour durant ces quinze dernières années dans le but de développer un usage réfléchi des TIC en éducation. Parmi celles-ci épinglons les « Plans TIC", la mise au point d’un curriculum de formation relatif aux usages et aux apports des médias et des TIC en enseignement destiné aux futurs enseignants, la mise en réseau d’enseignants du supérieur, la constitution de communautés d’apprenants supportées par les TIC. Plans d’équipement des écoles, projets-pilotes, formation initiale et continuée des enseignants en matière de TICE, réseaux de partage… convergent vers un même objectif : développer, expérimenter et diffuser des activités d’apprentissage à hautes plus-values. Des scénarios pédagogiques exploitant différents types d’outils/services technologiques et supports (ordinateurs, tablettes, tableaux interactifs…) et leurs plus-values sont mis au point afin de développer les savoirs, savoir-faire et savoir-être des apprenants, non seulement en rapport aux apprentissages scolaires, mais aussi dans l’optique d’un transfert dans la vie quotidienne, citoyenne et professionnelle. Certaines de ces initiatives seront présentées en les situant dans une approche systémique. Nous mettrons l’accent sur ce qui les unit, les facteurs facilitateurs et les obstacles rencontrés lors de leur implémentation sur le terrain et proposerons quelques recommandations. [less ▲]

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See detailPromotion of physical activity in schools
Cloes, Marc ULg

Conference (2014, May 01)

This presentation will answer to the following questions: (1) Does the school play a role in PA promotion? (2) What are the dimensions of PA at school? (3) How to determine the potential role of the ... [more ▼]

This presentation will answer to the following questions: (1) Does the school play a role in PA promotion? (2) What are the dimensions of PA at school? (3) How to determine the potential role of the school in PA promotion? (4) What kind of projects to implement? (5) What do we have to remember? It will be based on an overview of the literature and will provide practical implications for researchers and practitioners. [less ▲]

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See detailThe Transcription Factor EGR1 Localizes to the Nucleolus and Is Linked to Suppression of Ribosomal Precursor Synthesis
Ponti, Donatella; Bellenchi, Gian Carlo; Puca, Rosa et al

in PLoS ONE (2014), 9(5),

EGR1 is an immediate early gene with a wide range of activities as transcription factor, spanning from regulation of cell growth to differentiation. Numerous studies show that EGR1 either promotes the ... [more ▼]

EGR1 is an immediate early gene with a wide range of activities as transcription factor, spanning from regulation of cell growth to differentiation. Numerous studies show that EGR1 either promotes the proliferation of stimulated cells or suppresses the tumorigenic growth of transformed cells. Upon interaction with ARF, EGR1 is sumoylated and acquires the ability to bind to specific targets such as PTEN and in turn to regulate cell growth. ARF is mainly localized to the periphery of nucleolus where is able to negatively regulate ribosome biogenesis. Since EGR1 colocalizes with ARF under IGF-1 stimulation we asked the question of whether EGR1 also relocate to the nucleolus to interact with ARF. Here we show that EGR1 colocalizes with nucleolar markers such as fibrillarin and B23 in the presence of ARF. Western analysis of nucleolar extracts from HeLa cells was used to confirm the presence of EGR1 in the nucleolus mainly as the 100 kDa sumoylated form. We also show that the level of the ribosomal RNA precursor 47S is inversely correlated to the level of EGR1 transcripts. The EGR1 iseffective to regulate the synthesis of the 47S rRNA precursor. Then we demonstrated that EGR1 binds to the Upstream Binding Factor (UBF) leading us to hypothesize that the regulating activity of EGR1 is mediated by its interaction within the transcriptional complex of RNA polymerase I. These results confirm the presence of EGR1 in the nucleolus and point to a role for EGR1 in the control of nucleolar metabolism. [less ▲]

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See detailMicrolensing of the broad-line region in the quadruply imaged quasar HE0435-1223
Braibant, Lorraine ULg; Hutsemekers, Damien ULg; Sluse, D. et al

in Astronomy and Astrophysics (2014), 565

Using infrared spectra of the z = 1.693 quadruply lensed quasar HE0435-1223 acquired in 2009 with the spectrograph SINFONI at the ESO Very Large Telescope, we have detected a clear microlensing effect in ... [more ▼]

Using infrared spectra of the z = 1.693 quadruply lensed quasar HE0435-1223 acquired in 2009 with the spectrograph SINFONI at the ESO Very Large Telescope, we have detected a clear microlensing effect in images A and D. While microlensing affects the blue and red wings of the Hα line profile in image D very differently, it de-magnifies the line core in image A. The combination of these different effects sets constraints on the line-emitting region; these constraints suggest that a rotating ring is at the origin of the Hα line. Visible spectra obtained in 2004 and 2012 indicate that the MgII line profile is microlensed in the same way as the Hα line. Our results therefore favour flattened geometries for the low-ionization line-emitting region, for example, a Keplerian disk. Biconical models cannot be ruled out but require more fine-tuning. Flux ratios between the different images are also derived and confirm flux anomalies with respect to estimates from lens models with smooth mass distributions. Based on observations made with the ESO-VLT, Paranal, Chile; Proposal 084.B-0013 (PI: Rix).Tables 2, 3 and Appendix A are available in electronic form at <A href="http://www.aanda.org/10.1051/0004-6361/201423633/olm">http://www.aanda.org</A> [less ▲]

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See detailForest radiative transfer models: which approach for which application?
Ligot, Gauthier ULg; Balandier, Philippe; Courbaud, Benoît et al

in Canadian Journal of Forest Research = Journal Canadien de la Recherche Forestière (2014), 44(5), 385-397

Detailed reference viewed: 30 (14 ULg)
See detailNew Paleolithic human remains from the “Troisième caverne” of Goyet (Belgium)
Rougier; Crevecoeur, I.; Beauval, C. et al

Scientific conference (2014, May 01)

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See detailPlateforme interactive utilisée comme outil diagnostique et de remédiation adapté aux grandes populations étudiantes suivant un cours de physique
Marique, Pierre-Xavier ULg; Hoebeke, Maryse ULg

Conference (2014, May 01)

La réforme des études de médecine introduite en 2012 en Communauté Française (Belgique) a fortement modifié les programmes de cours, entre autres celui de physique, pour lequel certaines notions sont ... [more ▼]

La réforme des études de médecine introduite en 2012 en Communauté Française (Belgique) a fortement modifié les programmes de cours, entre autres celui de physique, pour lequel certaines notions sont désormais considérées comme prérequises. Conscientes que celles-ci ne sont pas toujours acquises par les étudiants, les équipes pédagogiques de l'ULg ont élaboré des systèmes de remédiation. Un espace en ligne a notamment été développé, parallèlement au cours présentiel (cours ex-cathedra, répétitions et laboratoires), afin de permettre aux enseignants et aux étudiants d'évaluer les difficultés et lacunes de ces derniers et d’y remédier. Cet outil est conçu pour offrir une aide spécifique adaptée à chacun malgré le nombre important d’étudiants inscrits (800 en 2013). Ils peuvent y travailler, de manière progressive et autonome, les aspects théoriques (notes et tests formatifs) et pratiques (exercices, problèmes décomposés ou non). Des tests diagnostiques en début et fin de parcours permettent aux apprenants d’apprécier leur évolution. De plus, la plate-forme centralise différents outils interactifs (forums, calendrier, annonces, …) accompagnant l’étudiant dans l’organisation de son apprentissage. Les premières analyses de traces indiquent une corrélation entre travail en ligne et réussite. Une adaptation progressive de l’outil sera basée sur l’analyse des résultats et du ressenti de étudiants. [less ▲]

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See detailBias correction using data assimilation: Application on the Lorenz ’95 and NEMO-LIM models.
Canter, Martin ULg; Barth, Alexander ULg

Poster (2014, May 01)

Data assimilation has been used for decades in fields like engineering or signal processing to improve forecast models. Ensemble Kalman filters and other sequential data assimilation methods are examples ... [more ▼]

Data assimilation has been used for decades in fields like engineering or signal processing to improve forecast models. Ensemble Kalman filters and other sequential data assimilation methods are examples of developments which reduce the uncertainty of the model by taking observations into account. The widespread interest in addressing systematic forecast model errors only arose when the advances in modelling, data assimilation and computational power had reduced random errors to the point of commensurability with systematic errors, also known as bias. We present here a new method of bias correction using data assimilation. This method is based on the stochastic forcing of a model to correct bias. First, through a preliminary run, we estimate the bias of the model and its possible sources. Then, we establish a forcing term which is directly added inside the model’s equations. We create an ensemble of runs and consider the forcing term as a control variable during the assimilation of observations. We then use this analysed forcing term to correct the bias of the model. Since the forcing is added inside the model, it acts as a source term, unlike external forcings such as wind. This procedure has been developed and successfully tested with a twin experiment on a Lorenz 95 model. Indeed, we were able to estimate and recover an artificial bias that had been added into the model. This bias had a spatial structure and was constant through time. The mean and behaviour of the corrected model corresponded to those the reference model. It is currently being applied and tested on the sea ice ocean NEMO LIM model, which is used in the PredAntar project. NEMO LIM is a global and low resolution (2 degrees) coupled model (hydrodynamic model and sea ice model) with long time steps allowing simulations over several decades. Due to its low resolution, the model is subject to bias in area where strong currents are present. We aim at correcting this bias by using perturbed current fields from higher resolution models and randomly generated perturbations. [less ▲]

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See detailDetermination of the magnetic penetration depth in a superconducting Pb film
Brisbois, Jérémy ULg

Conference (2014, May 01)

By means of scanning Hall probe microscopy technique we accurately map the magnetic field pattern produced by Meissner screening currents in a thin superconducting Pb stripe. The obtained field profile ... [more ▼]

By means of scanning Hall probe microscopy technique we accurately map the magnetic field pattern produced by Meissner screening currents in a thin superconducting Pb stripe. The obtained field profile allows us to quantitatively estimate the Pearl length Λ without the need of pre-calibrating the Hall sensor. This fact contrasts with the information acquired through the spatial field dependence of an individual flux quantum where the scanning height and the magnetic penetration depth combine in a single inseparable parameter. The derived London penetration depth λL coincides with the values previously reported for bulk Pb once the kinetic suppression of the order parameter is properly taken into account. [less ▲]

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See detailOutplacement adequacy and benefits: The mediating role of retrospective justice
Marzucco, Laurence ULg; Hansez, Isabelle ULg

Poster (2014, May)

ABSTRACT We examined the relationships between perceived outplacement adequacy, retrospective justice and outplacement benefits for redundant employees using outplacement services. Based on an ... [more ▼]

ABSTRACT We examined the relationships between perceived outplacement adequacy, retrospective justice and outplacement benefits for redundant employees using outplacement services. Based on an outplacement experience perceived as adequate, victims formed retrospective justice perceptions about their former organization that in turn, impacted their negative emotions, well-being, future perspectives and job search. PRESS PARAGRAPH The increasing prevalence of organizational downsizing has been matched by growth in the provision of outplacement services over the last decade. Despite this rapid growth and ongoing need for outplacement services, little is yet known about the perceived adequacy and the benefits of these services for redundant employees using them. Our results indicated that an outplacement experience perceived as adequate for redundant employees retrospectively fosters their impressions of justice about the dismissing organization; this leads in turn to satisfactory benefits for them: reduction of negative emotions, enhancement of their perceived well-being, future perspectives, and job-seeking activities. [less ▲]

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See detailEvent justice and social entity justice: A cross-lagged analysis
Marzucco, Laurence ULg; Hansez, Isabelle ULg

Poster (2014, May)

ABSTRACT This study aimed to examine the directionality of the relationship between event justice and social entity justice. Using two samples and a cross-lagged panel analysis with two measurement times ... [more ▼]

ABSTRACT This study aimed to examine the directionality of the relationship between event justice and social entity justice. Using two samples and a cross-lagged panel analysis with two measurement times, social entity justice was found to predict event justice (procedural, distributive, interpersonal and informational justice event), supporting the top-down process. PRESS PARAGRAPH The life of organizations is punctuated by a wide range of managerial decisions (e.g., hiring, performance appraisal or organizational change). Facing such events, employees evaluate the fairness of the situation experienced. However, little is known about how employees develop justice judgments. This study shows that employees’ fairness perceptions about their organization influence their interpretation of the fairness of subsequent events involving the organization. Building and fostering a climate of justice is therefore of primary importance for organizations, since global fairness perceptions about the organization may help employees to perceive a specific event, such as a managerial decision, as being fair. [less ▲]

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See detailAméliorer la formation clinique en logopédie par un stage socle au sein de l'université
Martinez Perez, Trecy ULg; Willems, Sylvie ULg; Maillart, Christelle ULg

Conference (2014, May)

La formation clinique des étudiants en logopédie (orthophonie) occupe une place importante dans leur cursus. Cette formation se dispense principalement via des stages réalisés dans des structures ... [more ▼]

La formation clinique des étudiants en logopédie (orthophonie) occupe une place importante dans leur cursus. Cette formation se dispense principalement via des stages réalisés dans des structures extérieures au centre de formation. Si cette ouverture permet aux étudiants de se confronter à la réalité du terrain, elle implique en contrepartie une hétérogénéité des lieux de stage et, par conséquent, une hétérogénéité de la formation avec certaines compétences qui sont peu ou pas travaillées dans certains lieux de stage. Face à cette problématique, un stage « socle », garant d’un base commune préalable, est désormais proposé à tous les étudiants du Master 1 Logopédie de l’Université de Liège au sein de la clinique universitaire. Ce dispositif poursuit un double objectif : (a) permettre à tous les étudiants en logopédie d’accéder aux apprentissages de base nécessaires pour une pratique future de qualité, (b) par son design, accompagner l’étudiant dans le développement réflexif et intégré de plusieurs compétences professionnelles du logopède. Plus précisément, ce stage de 60H se réalise en binôme. Chaque binôme participe à cinq séances de quatre heures sur la réalisation d’un bilan logopédique. Par ailleurs, un système de caméra permet aux étudiants d’observer activement le bilan réalisé par un second binôme et sert de support pour une séance de feedback. En 2012-2013, l’évaluation du dispositif indique notamment que : pour 84% des étudiants, ce dispositif leur a permis d’apprendre et/ou de pratiquer des notions qui ne sont pas abordé par ailleurs dans leur parcours de formation ; pour 82% des étudiants, ce dispositif les a aidé à relier la pratique aux notions abordées aux cours ; 100% des étudiants pensent pouvoir utiliser ce qu’ils ont développé lors du dispositif dans leur pratique professionnelle. [less ▲]

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See detailAnalyses croisées du monde du travail
Smette, Bernard ULg

in Cahiers du GRM (2014), 5

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See detailDark Atoms and Dark Radiation
Khlopov, Maxim; Belotsky, Konstantin; Cudell, Jean-René ULg et al

Book published by Hindawi Publishing Corporation (2014)

We have invited investigators to contribute original research and review articles that seek to define the possible physical nature of composite dark matter and its constituents, to stimulate the ... [more ▼]

We have invited investigators to contribute original research and review articles that seek to define the possible physical nature of composite dark matter and its constituents, to stimulate the experimental searches and to suggest astrophysical tests for their effects. The collected papers in this special issue represent only a first small step in the approach to the thorough investigation of the topic of dark atoms and dark radiation, demonstrating the wide but far from complete variety of possible aspects of this problem. [less ▲]

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