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See detailThe bottom up innovation and entrepreneurship in smart cities, case of Indian cities
Kummitha, Rama; Crutzen, Nathalie ULg

Conference (2016, March)

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See detailReduced Order Model for Accounting for High Frequency Effects in Power Electronic Components
Paquay, Yannick ULg; Geuzaine, Christophe ULg; Hasan, Md. Rokibul et al

in IEEE Transactions on Magnetics (2016)

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See detailNonlinear Interpolation on Manifold of Reduced Order Models in Magnetodynamic Problems
Paquay, Yannick ULg; Bruls, Olivier ULg; Geuzaine, Christophe ULg

in IEEE Transactions on Magnetics (2016), 52(3), 1-4

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See detailLe sensible chez Franz Brentano
Gauvry, Charlotte ULg

Conference (2016, March)

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See detailSilvia PAÏN : Manuel de gestion du mobilier archéologique: Méthodologie et pratiques
Drouguet, Noémie ULg

in CeROArt : Conservation, Exposition, Restauration d'Objets d'Art (2016), Hors-Série 5

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See detailDecoding intracranial EEG data with multiple kernel learning method
Schrouff, Jessica ULg; Mourao-Miranda, Janaina; Phillips, Christophe ULg et al

in Journal of Neuroscience Methods (2016), 261

Machine learning models have been successfully applied to neuroimaging data to make predictions about behavioral and cognitive states of interest. While these multivariate methods have greatly advanced ... [more ▼]

Machine learning models have been successfully applied to neuroimaging data to make predictions about behavioral and cognitive states of interest. While these multivariate methods have greatly advanced the field of neuroimaging, their application to electrophysiological data has been less common especially in the analysis of human intracranial electroencephalography (iEEG, also known as electrocorticography or ECoG) data, which contains a rich spectrum of signals recorded from a relatively high number of recording sites. In the present work, we introduce a novel approach to determine the contribution of different bandwidths of EEG signal in different recording sites across different experimental conditions using the Multiple Kernel Learning (MKL) method. To validate and compare the usefulness of our approach, we applied this method to an ECoG dataset that was previously analysed and published with univariate methods. Our findings proved the usefulness of the MKL method in detecting changes in the power of various frequency bands during a given task and selecting automatically the most contributory signal in the most contributory site(s) of recording. With a single computation, the contribution of each frequency band in each recording site in the estimated multivariate model can be highlighted, which then allows formulation of hypotheses that can be tested a posteriori with univariate methods if needed. [less ▲]

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See detailHCOOH distributions from IASI for 2008-2014: comparison with ground-based FTIR measurements and a global chemistry-transport model
Pommier, M.; Clerbaux, C.; Coheur, P.-F. et al

in Atmospheric Chemistry & Physics Discussions (2016), 2016

Formic acid (HCOOH) is one of the most abundant volatile organic compounds in the atmosphere. It is a major contributor to rain acidity in remote areas. There are however large uncertainties on its ... [more ▼]

Formic acid (HCOOH) is one of the most abundant volatile organic compounds in the atmosphere. It is a major contributor to rain acidity in remote areas. There are however large uncertainties on its sources and sinks, and HCOOH is misrepresented by global chemistry-transport models. This work presents global distributions from 2008 to 2014 as derived from the measurements of the Infrared Atmospheric Sounding Interferometer (IASI), based on conversion factors between brightness temperature differences and representative retrieved total columns over seven regions: Africa N, Africa S, Amazonia, Atlantic, Australia, Pacific and Russia. The dependence of the thermal contrast is taking account in the conversion method. This conversion presents errors lower than 20 % for total columns ranging between 0.5 and 1 × 1016 molec/cm2 but reaches higher values, up to 78 %, for columns lower than 0.3 × 1016 molec/cm2. Signatures from biomass burning events are highlighted, such as in the Southern Hemisphere and in Russia, as well as biogenic emission sources, e.g. over Eastern US. A comparison between 2008 and 2014 with ground-based FTIR measurements obtained at 4 locations (Maido and Saint-Denis at La Réunion, Jungfraujoch and Wollongong) is shown. Although IASI columns are found to correlate well with FTIR data, a large bias (> 100 %) is found over the two sites at La Réunion. A better agreement is found at Wollongong with a negligible bias. The comparison also highlights the difficulty for IASI to retrieve the total columns over mountainous regions such as Jungfraujoch. A comparison of the retrieved columns with the global chemistry-transport model IMAGESv2 is also presented, showing the good representation of the seasonal and inter-annual cycles over America, Australia, Asia and Siberia. A global model underestimation of the distribution and a misrepresentation of the seasonal cycle over India are also noted. A small positive trend in the IASI columns is also observed over Australia, Amazonia and India over 2008–2014 (from 0.7 to 1.5 %/year), while a decrease of ~ 0.8 %/year is measured over Siberia. [less ▲]

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See detailWeak magnetic field, solid-envelope rotation, and wave-induced N-enrichment in the SPB star zeta Cassiopeiae
Briquet, Maryline ULg; Neiner, C.; Petit, P. et al

in Astronomy and Astrophysics (2016), 587

Aims. The main-sequence B-type star zeta Cassiopeiae is known as a N-rich star with a magnetic field discovered with the Musicos spectropolarimeter. We model the magnetic field of the star by means of 82 ... [more ▼]

Aims. The main-sequence B-type star zeta Cassiopeiae is known as a N-rich star with a magnetic field discovered with the Musicos spectropolarimeter. We model the magnetic field of the star by means of 82 new spectropolarimetric observations of higher precision to investigate the field strength, topology, and effect. Methods. We gathered data with the Narval spectropolarimeter installed at Télescope Bernard Lyot (TBL; Pic du Midi, France) and applied the least-squares deconvolution technique to measure the circular polarisation of the light emitted from zeta Cas. We used a dipole oblique rotator model to determine the field configuration by fitting the longitudinal field measurements and by synthesizing the measured Stokes V profiles. We also made use of the Zeeman-Doppler imaging technique to map the stellar surface and to deduce the difference in rotation rate between the pole and equator. Results. zeta Cas exhibits a polar field strength B_pol of 100-150 G, which is the weakest polar field observed so far in a massive main-sequence star. Surface differential rotation is ruled out by our observations and the field of zeta Cas is strong enough to enforce rigid internal rotation in the radiative zone according to theory. Thus, the star rotates as a solid body in the envelope. Conclusions. We therefore exclude rotationally-induced mixing as the cause of the surface N-enrichment. We discuss that the transport of chemicals from the core to the surface by internal gravity waves is the most plausible explanation for the nitrogen overabundance at the surface of zeta Cas. [less ▲]

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See detailEstetrols’ Potential for Neuroprotection Following the injury to the Developing Brain: Preclinical Studies
Tskitishvili, Ekaterine ULg; Nisolle, Michelle ULg; Noël, Agnès ULg et al

in The 17th World Congress of Gynecological Endocrinology, Florence 2-5 March 2016 (2016, March)

Context: Hypoxic-Ischemic encephalopathy (HIE) remains a major cause of perinatal brain injury. The brain rapidly increases in size, shape and complexity during the second and third trimesters. A sentinel ... [more ▼]

Context: Hypoxic-Ischemic encephalopathy (HIE) remains a major cause of perinatal brain injury. The brain rapidly increases in size, shape and complexity during the second and third trimesters. A sentinel event in late pregnancy or the intrapartum period may have an acute profound effect on a previously neurologically intact fetus, leading to the development of (HIE). The nature of the deficits is dependent on the gestational age and severity of the insult, though it is seldom reported in preterm infants. Studies in animal models of HIE may provide important information for the development of treatment for this pathological condition. Estetrol (E4) is a recently described estrogen with four hydroxyl-groups that is synthesized exclusively during pregnancy by the human fetal liver. Objective: In this study, we evaluated E4’s neuroprotective and therapeutic potency in neonatal (in vivo) HIE model of the immature 7-day-old newborn rat. Methods: Rat pups body temperatures were examined along with their body and brain weights. Brains were studied at the level of the hippocampus and cortex. Intact cell counting and expressions of markers for neuronal early grey matter damage (microtubule-associated protein-2 (MAP-2)), neurogenesis (doublecortin (DCX)) and angiogenesis (vascular-endothelial growth factor (VEGF)) were evaluated by histo- and immunohistochemistry. The serum levels of two markers of brain damage (S100B and glial fibrillary acidic protein (GFAP)) were measured by ELISA. Results: Our results demonstrate that E4 has a significant neuroprotective and therapeutic effects. Estetrol decreases the early gray matter loss, and promotes neuro- and angiogenesis in vivo. Estetrol treatment has no effects on body weight, brain weight or body temperature. Conclusion: Taken together, E4 might become an important safe and physiological substance to treat neonatal HIE. [less ▲]

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See detailDevelopment of a translation stage for in situ non-invasive analysis and high resolution imaging
Strivay, David ULg; Clar, Mathieu ULg; Rakkaa, Saïd ULg et al

Poster (2016, March)

Non-invasive imaging techniques and analytical instrumentation for cultural heritage object studies have undergone a tremendous development over the last years. Many new miniature and/or handheld systems ... [more ▼]

Non-invasive imaging techniques and analytical instrumentation for cultural heritage object studies have undergone a tremendous development over the last years. Many new miniature and/or handheld systems have been developed and optimized. Nonetheless, these instruments are usually used with a tripod or a manual position system. This is very time consuming when performing point analysis or 2D scanning of a surface. The Centre Européen d’Archéométrie (CEA) has build a translation system made of pluggable rails of 1 m long with a maximum length and height of 3 m. Three motors embedded in the system allow the platform to be moved along these axis, toward and backward from the sample. The rails hold a displacement system, providing a continuous movement. Any position can be reached with a reproducibility of 0.1 mm. The displacements are controlled by an Ethernet connection through a laptop computer running a multiplatform homemade software written in JAVA. This software allows a complete control over the positioning using a simple, unique, and concise interface. Automatic scanning can be performed over a large surface of 3 meters on 3 meters. The Ethernet wires provide also the power for the different motors and, if necessary the detection head. The platform has been originally designed for a XRF detection head (with its full power alimentation) but now can accommodate many different systems like IR reflectography, digital camera, hyperspectral camera, Raman probes, etc. The positioning system can be modified to combine the acquisition software of the imaging or analytical techniques and the positioning software. [less ▲]

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See detail“Color is a kind of holy substance for me”: analytical study of the Sam Francis’ palette from the 1940’s to the 1990’s
Defeyt, Catherine ULg; Mazurek, Joy; Zebala, Aneta et al

Poster (2016, March)

The Sam Francis’s colors, literally described as vivid, saturated, pure, vibrant intense and rich, largely contribute to the unique character of his work. This idiosyncrasy explains the interest in ... [more ▼]

The Sam Francis’s colors, literally described as vivid, saturated, pure, vibrant intense and rich, largely contribute to the unique character of his work. This idiosyncrasy explains the interest in conducting an extended study on the Francis’ painting materials through analytical techniques. On the other hand, many Francis’ paintings display colored surfaces that exhibit bronzing, fluorescent or opalescent effects. As a consequence, retouching paint losses from Sam Francis works may become a challenging task for the involved conservators, the degree of the color matching required in the imitative technique being particularly difficult to attain, in the presence of such surfaces. Furthermore, the attained degree of the color match has to be conserved in all conditions of illumination and observation. The use of pigments chemically similar to the original ones is often necessary for matching highly chromatic pigments. Though, many modern synthetic organic pigments (SOPs) possess high color strength. That is why the characterization of the Francis palette would provide helpful information to the conservators, which have to deal with this type of issue. The upcoming Getty publication Sam Francis: The Artist’s Materials, planned for 2016, offered the opportunity for in-depth analyses of hundreds paint samples. Almost three hundreds of paint fragments supplied by the Sam Francis Foundation have been investigated at the GCI laboratory, by using three complementary analytical techniques, Py-GC-MS, Raman and FTIR spectroscopies. The Raman spectroscopy is one of the most efficient techniques for identifying SOPs in paint systems, while the Py-GC-MS and FTIR methods provide essential information concerning the binding media. The analyzed paint fragments were sampled from twenty-nine canvases and works on paper, made between 1946 and 1992. Although, primary established in Southern California, Sam Francis spent numerous long journeys in different places around the world, including Paris, Bern, Mexico City, New York and Tokyo. However, the material study has outlined the uninterrupted use of` certain classes of SOPs in specific colors. For example, copper phthalocyanine (CuPc) pigments were systematically detected in the blue and green samples, while azo pigments have been identified in most of the yellow areas sampled from post 1940s works. Regardless of the support and the paint technique, the Francis’ blues primary contain Ultramarine and/or CuPc blue pigments. And, it has been shown that the bronzing blue surfaces noticed for some of the investigated artworks correspond to PB15-based paint films. The present study has also underlined the recurrent use of perinone orange and dioxazine violet in fluorescent orange and purple area. Despite the early introduction of SOPs, on the Francis’ palette, the works dating from the 1940’s remained mainly composed of traditional inorganic pigments, for instance lead white and red, chrome yellow, viridian and iron oxides. Interestingly, various binding media, i.e. Shellac gum, modified and unmodified oils, PVA, alkyd resins and acrylic copolymers have been identified. Actually, the investigated samples have pointed out the frequent combination of more than three types of binders on a same painting. Through the identification of the various SOPs used by Francis over fifty years, this research provide helpful information for selecting the most appropriate retouching pigments. [less ▲]

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See detailSURVEYS OF APHIDS AND POTATO VIRUS Y IN POTATO FIELDS IN WALLONIA, BELGIUM: A FOUR YEAR OVERVIEW
Bosquée, Emilie ULg; Yattara, Almouner A.; Crutzen, François et al

in Journal of Plant Pathology [=JPP] (2016)

Populations of Potato virus Y (PVY) and aphids were characterized in potato seed and stock production fields in southern Belgium (Wallonia) from 2009 to 2012. More than 40 aphid species were identified ... [more ▼]

Populations of Potato virus Y (PVY) and aphids were characterized in potato seed and stock production fields in southern Belgium (Wallonia) from 2009 to 2012. More than 40 aphid species were identified using yellow pan traps. Four thousands potato leaf samples collected in 87 plots from 29 fields were analysed for the presence and typing of PVY strains by RT-PCR. PVY was detected in 26%, 20% and 60% of the seed plots tested from 2009 to 2011, respectively. A higher prevalence of PVY was observed in plots of stock potatoes (60% in 2010 and 67% in 2011). The N/NTN strain of PVY was predominant, representing 70-99% of the strains. [less ▲]

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See detailL’entretien de tutorat documenté : un accompagnement réflexif ?
Alonso Vilches, Vincent ULg; Pirard, Florence ULg

in Education Permanente (2016), 206(1), 131-138

Notre contribution interroge l’activité tutorale dans un métier adressé à autrui, celui des professionnels de l’enfance. Elle souligne la complexité d’une telle activité dans un travail fondé sur des ... [more ▼]

Notre contribution interroge l’activité tutorale dans un métier adressé à autrui, celui des professionnels de l’enfance. Elle souligne la complexité d’une telle activité dans un travail fondé sur des référents multiples, qui nécessitent le développement d’une réflexivité sensible à la singularité des situations quotidiennes. Elle propose une analyse de moments d’entretien de tutorat accompagnés par un professionnel sur base d’une documentation vidéo. Elle montre que ces moments ne permettent pas forcément au stagiaire de développer une représentation signifiante de la situation ni d’en dégager les inférences nécessaires pour ajuster son action. [less ▲]

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See detailNote on the numerical solution of the scalar Helmholtz equation in a nanotorus with uniform Dirichlet boundary conditions
Nguyen, Ngoc Duy ULg; Evrard, Roger ULg; Stroscio, Michael

E-print/Working paper (2016)

This note describes the solution of the Helmholtz equation inside a nanotorus with uniform Dirichlet boundary conditions. The eigenfunction symmetry is discussed and the lower-order eigenvalues and ... [more ▼]

This note describes the solution of the Helmholtz equation inside a nanotorus with uniform Dirichlet boundary conditions. The eigenfunction symmetry is discussed and the lower-order eigenvalues and eigenfunctions are shown. The similarity with the case of a long cylinder and with that of the vibrations of a circular elastic membrane is discussed. This similarity is used to propose a classification scheme of the eigenfunctions based on three indices. [less ▲]

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See detailA One-year Survey of Microsporum audouinii infections in Belgium: epidemiological and genotypic characterisation
SACHELI, Rosalie ULg; ADJETEY BAHUN, Akolé ULg; DARFOUF, Rajae ULg et al

in Clinical Microbiology and Infection (2016), 22(3), 2859-28517

During recent years the proportion of tinea capitis (TC) infections due to Microsporum audouinii (M. audouinii) has increased both in Belgium and other European countries. To better understand the ... [more ▼]

During recent years the proportion of tinea capitis (TC) infections due to Microsporum audouinii (M. audouinii) has increased both in Belgium and other European countries. To better understand the emergence of this species in the country, the Belgian National Reference Center (NRC) for dermatophytes launched an epidemiological survey on the main anthropophilic dermatophytes causing TC in Belgium and including the genomic characterization of M. audouinii isolates. In total, 116 strains of M. audouinii were confirmed and characterized by the DiversiLab® system (bioMérieux). Six genotypic variants were identified, among which one major group included 90 isolates and the reference strain. Another variant group (11 strains) was exclusively confined to a geographical region in South Belgium. Analysis of epidemiological characteristics of the infected population showed that the main age category concerned 5-9 year-old children with a sex ratio (Male/Female) of 1.97. Data concerning the geographic origin of the family revealed a majority of Belgian nationality (44.7%), suggesting that the contamination has originated in Belgium. Other nationalities primarily originated from Africa. At this time, no clear correlation has been established between one particular strain and a specific country of origin. [less ▲]

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See detailLe parc scientifique du Sart Tilman, "Liege Science Park"
Merenne-Schoumaker, Bernadette ULg

in Pierre Geurts, Caroline Lamarche (Ed.) Dérivations 2 Pour le débat urbain (2016)

L'article retrace l'histoire du parc scientifique de Liège et tente d'en montrer les impacts sur le redéploiement régional. Il cherche aussi à développer une réflexion sur le concept de parc scientifique ... [more ▼]

L'article retrace l'histoire du parc scientifique de Liège et tente d'en montrer les impacts sur le redéploiement régional. Il cherche aussi à développer une réflexion sur le concept de parc scientifique, ses liens avec la recherche ainsi que les enjeux et défis liés au futur du tout parc de ce genre [less ▲]

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See detailMobiliser la culture du pays d’origine, un défi pour l’intégration des migrants?
Mescoli, Elsa ULg; Gsir, Sonia ULg

Conference (2016, March)

La culture constitue pour les migrants et leurs pays d’origine un moyen de maintenir des liens réciproques après la migration. Mais quels sont les enjeux de la mobilisation de la culture d’origine pour ... [more ▼]

La culture constitue pour les migrants et leurs pays d’origine un moyen de maintenir des liens réciproques après la migration. Mais quels sont les enjeux de la mobilisation de la culture d’origine pour l’intégration des migrants dans leurs nouveaux pays de résidence ? Cette présentation analyse le déploiement de la culture du pays d’origine à trois niveaux : celui des pratiques quotidiennes des migrants, des politiques d’intégration et de diaspora et enfin, le niveau des associations, en particulier les centres culturels établis en Europe par les pays d’origine des migrants. Les pratiques culturelles des migrants et les actions et institutions culturelles mises en place par les pays d’origine sont confrontées au cadre légal européen en matière de diversité culturelle mais aussi aux politiques et discours sur l’intégration des migrants. La perspective à la fois anthropologique et sociologique adoptée révèle les processus de domination culturelle qui sont à l’œuvre. Elle permet aussi de questionner l’idée d’identité culturelle en montrant le dynamisme qui caractérise les cultures mais aussi la créativité des communautés locales dans un environnement globalisé. Finalement, on constate qu’une variété de facteurs est en jeu dans les processus d’intégration des migrants, que les dynamiques de la culture elle-même déterminent des appartenances multiples et aussi que les identités se développent au sein des interactions entre cultures. Si on ne peut établir de lien causal et univoque entre les pratiques culturelles liées au pays d’origine et l’intégration des migrants dans le pays de résidence, on peut par contre se référer à la notion d’ethnicité et à sa fonction politique (Comaroff et Comaroff, 2009). [less ▲]

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See detailToxicity of organometal halide perovskite solar cells
Babayigit, Aslihan; Ethirajan, Anitha; Muller, Marc ULg et al

in Nature Materials (2016), 15

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See detailDrying induced shrinkage of Boom Clay: an experimental investigation
Prime, Noémie; Levasseur, Séverine; Miny, Laurent et al

in Canadian Geotechnical Journal (2016), 53(3), 396-409

Drying induced shrinkage of geomaterials may have a strong effect on geostructure stability and deformation. Settlement of foundations, fracture opening on slopes, roads, tunnel walls may be due to drying ... [more ▼]

Drying induced shrinkage of geomaterials may have a strong effect on geostructure stability and deformation. Settlement of foundations, fracture opening on slopes, roads, tunnel walls may be due to drying shrinkage. However, there is still a lack of knowledge concerning shrinkage evolution in time and shrinkage propagation within the material. In this study, the shrinkage of a specific clayey rock, Boom Clay, under drying conditions is experimentally investigated. This rock is a deep geological formation which is under study for high-level and long-life radioactive waste storage in Belgium. Two experimental campaigns are here presented. The first one, based on vapour equilibrium drying technique and completed by sample size manual measurement, aims to characterize the material shrinkage in balanced states. The second one, based on convective drying technique completed by shape monitoring using X-ray tomography, aims to analyse how shrinkage develops before reaching a steady state. Both approaches put in evidence the shrinkage anisotropy of this structurally bedded rock, with a ratio around 2 between the direction of maximum strains and the direction of minimum strains. However, the two drying techniques also provide complementary results, as the relation between the amount of shrinkage and the retention curve (for the uniform drying imposed with saline solutions) and the kinetics of shrinkage propagation inside the material (for the non-uniform drying imposed with air convection). [less ▲]

Detailed reference viewed: 79 (28 ULg)