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See detailAssessment of the NeQuick model at mid-latitudes using GNSS TEC and ionosonde data
Bidaine, Benoît ULiege; Warnant, René

in Advances in Space Research (2010), 45(9), 1122-1128

The modelling of the Total Electron Content (TEC) plays an important role in global navigation satellite systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones ... [more ▼]

The modelling of the Total Electron Content (TEC) plays an important role in global navigation satellite systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones constituting the mass market. For the latter and in the framework of Galileo, the NeQuick model has been chosen for correcting the ionospheric error contribution and will be integrated into a global algorithm providing the users with daily updated information. In order to reach the ionosphere error correction level objective, the model itself as well as its use for Galileo are investigated. In our comparison process, we take advantage of various ionosphere data from several European stations (Dourbes in Belgium, El Arenosillo and Roquetes in Spain) where ionosonde and GPS TEC data are available for different solar activity levels. These data allow us to study NeQuick representation of the ionosphere at mid-latitudes. Constraining the model with ionosonde measurements, we investigate the difference between GPS-derived vertical TEC and corresponding values from NeQuick for a high solar activity level (year 2002). With this approach, we reach residual errors of less than 20% in standard deviation. We especially highlight the improvements from the latest (second) version of NeQuick and show the critical importance of the topside formulation. [less ▲]

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See detailDissolved inorganic carbon dynamics and air-sea carbon dioxide fluxes during coccolithophorid blooms in the Northeast European continental margin (northern Bay of Biscay)
Suykens, Kim; Delille, Bruno ULiege; Chou, Lei et al

Poster (2010, May 03)

Balch et al. (2007) evaluated global pelagic contemporary calcification from remote sensing data (mainly associated to coccolithophores) to 1.6 ± 0.3 Pg PIC yr-1 (1 Pg = 1015 g; PIC = particulate ... [more ▼]

Balch et al. (2007) evaluated global pelagic contemporary calcification from remote sensing data (mainly associated to coccolithophores) to 1.6 ± 0.3 Pg PIC yr-1 (1 Pg = 1015 g; PIC = particulate inorganic carbon). This would imply that coccolithophores would be the most important pelagic calcifier in the oceans, since other estimates of contemporary global pelagic calcification range between 0.7 Pg PIC yr-1 based on accumulation rates and sediment trap data (Milliman et al. 1999), and 1.4 Pg PIC yr-1, based on the seasonal cycle of total alkalinity (TA) in the euphotic zone (Lee 2001). The development of coccolithophorid blooms affects the seawater carbonate chemistry, and air-sea CO2 fluxes, through the organic carbon pump and the carbonate counter-pump. The ratio between calcification (carbonate counter-pump), and organic carbon production (organic carbon pump), the C:P ratio, depends on the life cycle (bloom development), and growth conditions of coccolithophores. At the onset of the coccolithophorid bloom, when nutrients are available for growth, organic carbon production dominates over calcification (C:P << 1, the so-called organic phase). At the end of the bloom, in nutrient depleted conditions, and high irradiances (due to stronger stratification), organic carbon production decreases and calcification increases (C:P ≤ 1, the so-called inorganic phase). Several manipulative experiments to test the effect of ocean acidification on coccolithophores have shown that while calcification would decrease, the export of organic carbon would increase mainly through increasing transparent exopolymer particles (TEP) production. For a credible implementation in mathematical models of such feed-back mechanisms to allow the projection of a future evolution of carbon biogeochemistry under global change, it is required to understand present day biogeochemistry and ecology of naturally occurring pelagic calcifying communities. In particular, the overall effect of phytoplankton communities on the C:P ratio, and the net effect on carbonate chemistry, and related air-sea CO2 fluxes. [less ▲]

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See detailTowards a comprehensive C-budgeting approach of a cocoliothophorid bloom in the northern Bay of Biscay: results from PEACE project.
Harlay, Jérôme ULiege; Borges, Alberto ULiege; Delille, Bruno ULiege et al

Conference (2010, May 03)

During coccolithophorid blooms, carbon (C) cycling in the photic zone is driven by the production and the degradation of organic matter (primary production and community respiration), as well as the ... [more ▼]

During coccolithophorid blooms, carbon (C) cycling in the photic zone is driven by the production and the degradation of organic matter (primary production and community respiration), as well as the production and the dissolution of biogenic calcium carbonate (CaCO3). Organic and inorganic metabolisms lead to a transfer of carbon to depth and both impact the flows of carbon dioxide (CO2) in the water column and the CO2 flux across the air-sea interface. Furthermore, due to complex dynamics of coccolithophores, the impact of metabolic C fluxes on CO2 fluxes is variable in time, depending on the stage of the bloom development, and mainly on the ratio of calcification to primary production (CAL:GPP). Understanding and quantifying C cycling of coccolithophorid blooms in natural conditions is a prerequisite to correctly validate biogeochemical models aiming at predicting feedbacks related to ocean acidification, which incorporate knowledge obtained from perturbation laboratory experiments. We carried out a trans-disciplinary cruise on board the R/V Belgica at the continental margin of the Bay of Biscay, in the midst of a coccolithophorid bloom, during which 14C primary production (GPPp), 14C calcification (CAL) and O2-based pelagic community respiration rates (PCR) were determined in the water column. [less ▲]

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See detailRepräsentation et intentionnalité. Sur l’impossibilité de purger l’intentionnalité de tout objet immanent
Gyemant, Maria ULiege

in Bulletin d'Analyse Phénoménologique (2010, May 03)

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See detailBelgique : la diversité culturelle vue comme défi de la mondialisation à la solidité de l’Etat nation.
Verjans, Pierre ULiege

Speech/Talk (2010)

Créée en 1830 sur le modèle de l’Etat nation, la Belgique a été dirigée jusqu’en 1893 par une élite francophone sourde aux demandes de reconnaissance de la diversité culturelle. Pourtant, cette diversité ... [more ▼]

Créée en 1830 sur le modèle de l’Etat nation, la Belgique a été dirigée jusqu’en 1893 par une élite francophone sourde aux demandes de reconnaissance de la diversité culturelle. Pourtant, cette diversité culturelle était actée depuis près d’un millénaire et demi La montée en puissance du mouvement flamand depuis la décennie 1960 illustre les diverses facettes de la mondialisation : effet en retour de la décolonisation, émergence d’une économie post-industrielle, européanisation et atlantisation des politiques publiques provoquent une remise en cause de la légitimité de l’Etat nation unitaire. L’échec des négociations communautaires depuis 2007 et le blocage politique qui s’ensuit illustre la priorité accordée de nouveau à la question de la diversité culturelle en Belgique, après quinze ans d’accalmie. [less ▲]

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See detailETAPE Ensemble Travaillons Autour de la Petite Enfance
Vanmeerbeek, Marc ULiege; Bednarek, Stéphanie

Conference given outside the academic context (2010)

1. Les professionnels peuvent tomber facilement dans la stigmatisation des difficultés liées à la parentalité ; 2. Manque de compétences relationnelles et éducationnelles chez les intervenants médico ... [more ▼]

1. Les professionnels peuvent tomber facilement dans la stigmatisation des difficultés liées à la parentalité ; 2. Manque de compétences relationnelles et éducationnelles chez les intervenants médico-psychosociaux ; 3. Manque de cohérence entre les différents intervenants. [less ▲]

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See detailDissolved inorganic carbon dynamics and air-sea carbon dioxide fluxes during coccolithophorid blooms in the Northeast European continental margin (northern Bay of Biscay)
Suykens, Kim; Delille, Bruno ULiege; Chou, Lei et al

Poster (2010, May 02)

We present a data-set of dissolved inorganic carbon (DIC) obtained during three cruises in the northern Bay of Biscay carried out in June 2006, May 2007, and May 2008. During these cruises, blooms of ... [more ▼]

We present a data-set of dissolved inorganic carbon (DIC) obtained during three cruises in the northern Bay of Biscay carried out in June 2006, May 2007, and May 2008. During these cruises, blooms of coccolithophores occurred, as indicated by patches of high reflectance on remote sensing images, phytoplankton pigment signatures, and microscopic examinations. Total alkalinity (TA) showed a non-conservative behaviour as a function of salinity due to the cumulated effect of net community calcification (NCC) during bloom development on seawater carbonate chemistry. The cumulated impact of NCC and net community production (NCP) on DIC and the partial pressure of CO2 (pCO2) were evaluated. The decrease of DIC (and increase of pCO2) due to NCC was overwhelmingly lower than the decrease of DIC (and decrease of pCO2) due to NCP (NCC:NCP « 1). During the cruises, the northern Bay of Biscay acted as a sink of atmospheric CO2 (on average -9.7 mmol C m-2 d-1 for the 3 cruises). The overall effect of NCC in decreasing the CO2 sink during the cruises was low (on average 12% of total air-sea CO2 flux). If this is a general feature in naturally occurring phytoplankton blooms in the northern North Atlantic Ocean (where coccolithophorid blooms are the most intense and recurrent), and in the global ocean, then the potential feed-back on increasing atmospheric CO2 of the projected decrease of pelagic calcification due to thermodynamic CO2 “production” from calcification is probably minor compared to feed-backs related to changes of NCP. [less ▲]

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See detailSurvival of a convective core in low-mass solar-like pulsator HD 203608
Deheuvels, S.; Michel, Eric; Goupil, M. J. et al

in Astronomy and Astrophysics (2010), 514

Context. A 5-night asteroseismic observation of the F8V star HD 203608 was conducted in August 2006 with harps, followed by an analysis of the data, and a preliminary modeling of the star (Mosser et al ... [more ▼]

Context. A 5-night asteroseismic observation of the F8V star HD 203608 was conducted in August 2006 with harps, followed by an analysis of the data, and a preliminary modeling of the star (Mosser et al. 2008). The stellar parameters were significantly constrained, but the behavior of one of the seismic indexes (the small spacing δν[SUB]01[/SUB]) could not be fitted with the observed one, even with the best considered models. <BR /> Aims: We study the possibility of improving the agreement between models and observations by changing the physical properties of the inner parts of the star (to which δν[SUB]01[/SUB] is sensitive). <BR /> Methods: We show that, in spite of its low mass, it is possible to produce models of HD 203608 with a convective core. No such model was considered in the preliminary modeling. In practice, we obtain these models here by assuming some extra mixing at the edge of the early convective core. We optimized the model parameters using the Levenberg-Marquardt algorithm. <BR /> Results: The agreement between the new best model with a convective core and the observations is much better than for the models without. All the observational parameters are fitted within 1-Ï observational error bars. This is the first observational evidence of a convective core in an old and low-mass star such as HD 203608. In standard models of low-mass stars, the core withdraws shortly after the ZAMS. The survival of the core until the present age of HD 203608 provides very strong constraints on the size of the mixed zone associated to the convective core. Using overshooting as a proxy to model the processes of transport at the edge of the core, we find that to reproduce both global and seismic observations, we must have α[SUB]{ov[/SUB]} = 0.17 ± 0.03 H[SUB]p[/SUB] for HD 203608. We revisit the process of the extension of the core lifetime due to overshooting in the particular case of HD 203608. [less ▲]

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See detailGenome Sequence of the Edible Cyanobacterium Arthrospira sp. PCC 8005
Janssen, Paul; Morin, Nicolas; Mergeay, Max et al

in Journal of Bacteriology (2010), 192(9), 24652466

We determined the genome sequence of Arthrospira sp. PCC 8005, a cyanobacterial strain of great interest to the European Space Agency for its nutritive value and oxygenic properties in the Micro ... [more ▼]

We determined the genome sequence of Arthrospira sp. PCC 8005, a cyanobacterial strain of great interest to the European Space Agency for its nutritive value and oxygenic properties in the Micro-Ecological Life Support System Alternative (MELiSSA) biological life support system for long-term manned missions into space. [less ▲]

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See detailSPICE-Circuit Simulation of the Electrical Response of a Semiconductor Membrane to a Single-Stranded DNA Translocating Through a Nanopore
Leroux, Amandine ULiege; Destiné, Jacques ULiege; Vanderheyden, Benoît ULiege et al

in IEEE Transactiones on Nanotechnology (2010), 9(3), 322-329

In this paper, we describe a circuit-element model for the electric detection of biomolecules in translocation through a nanopore in a semiconductor-oxide-semiconductor (SOS) membrane. The biomolecules ... [more ▼]

In this paper, we describe a circuit-element model for the electric detection of biomolecules in translocation through a nanopore in a semiconductor-oxide-semiconductor (SOS) membrane. The biomolecules are simulated as a superposition of individual charges moving through the nanopore and inducing a charge variation on the membrane electrodes that is modeled as a current source. The SOS membrane is discretized into interconnected elementary circuit elements. The model is tested on the translocation of 11 base single-stranded C3AC7 DNA molecule, for which the electric signal shows good qualitative agreement with the multiscale device approach of Gracheva et al., while quantifying the low-pass filtering in the membrane. Overall, the model confirms the possibility of identifying the sequence of the DNA bases electrically. [less ▲]

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See detailL’Inventaire Systémique de Qualité de Vie en oncologie pédiatrique : développement d’un module spécifique
Missotten, Pierre ULiege; Hoyoux, Claire; Dupuis, Gilles et al

Poster (2010, May)

Introduction Dans la littérature pédiatrique relative à l’évaluation de la qualité de vie et de la qualité de vie liée à la santé, deux types bien distincts d’outils existent: les outils génériques et les ... [more ▼]

Introduction Dans la littérature pédiatrique relative à l’évaluation de la qualité de vie et de la qualité de vie liée à la santé, deux types bien distincts d’outils existent: les outils génériques et les outils spécifiques. Les mesures génériques s’adressent à tout enfant (Rodary, 2000). Elles permettent d’établir des comparaisons entre différents groupes d’enfants (malades et sains) mais peuvent ne pas être sensibles ni aux changements mineurs dans le fonctionnement d’un enfant ni aux aspects spécifiques de la maladie qui sont pourtant cliniquement pertinents dans sa vie (Harding, 2001; Patrick & Erikson, 1993; Raat et al., 2006). Les mesures spécifiques concernent les enfants atteints d’une maladie donnée: asthme, diabète, cancer,… (Rodary, 2000). Elles sont plus sensibles aux implications des différents traitements et sont probablement plus appropriées tant pour évaluer les interventions que pour comparer l’impact de traitements alternatifs (Eiser, 1997). Par contre, elles ne permettent pas de comparer la qualité de vie d’enfants et d’adolescents souffrant de maladies différentes (Levi & Drotar, 1998). De plus, leur spécificité s’oppose à la conception de la qualité de vie en tant que construction applicable à tous les enfants, les standards de qualité de vie étant universels (Wallander et al., 2001). Pour contrer ces inconvénients respectifs, le développement d’un troisième type d’outil -l’outil modulaire- est actuellement encouragé. Ce dernier se compose d’une partie générique à laquelle vient s’ajouter une partie spécifique à la pathologie. Objectif L’objectif de cette communication est de présenter le développement d’un module spécifique « cancer » se rattachant à la partie générique de l’Inventaire Systémique de Qualité de Vie pour Enfants (ISQV-E© ; Missotten, Etienne et Dupuis, 2007) et Adolescents (ISQV-Ados© ; Missotten, 2007). L’ISQV-E© et l’ISQV-Ados© sont des auto-questionnaires, respectivement destinés aux enfants de 8 à 12 ans et aux adolescents de 13 à 18 ans. Ils se différencient tant au niveau du contenu de certains items qu’au niveau du matériel proposé. Toutefois, tous deux évaluent dans quelle mesure chaque enfant ou adolescent parvient à atteindre les buts qu’il se fixe dans différents domaines de sa vie. Ces derniers recouvrent principalement le fonctionnement physique, le fonctionnement émotionnel, le fonctionnement social et familial et le fonctionnement cognitif. La spécificité de ces questionnaires tient à leur évaluation de la qualité de vie en termes d’écart entre la situation actuelle du jeune et son attente (but) et à leur prise en compte des capacités d’adaptation des enfants et adolescents. Méthode L’élaboration du module spécifique venant s’ajouter aux items génériques a été effectuée sur base de deux types d’informations: - discussions multidisciplinaires réunissant l’ensemble de l’équipe d’hémato-oncologie pédiatrique du CHR de la Citadelle. - recensement des outils spécifiques existant en oncologie pédiatrique et du seul outil modulaire ayant un module cancer : le Pediatric Quality of Life Inventory (Varni et al., 2002). Résultats Sur base de ces informations, 6 items spécifiques ont été générés: nausées et vomissements, fonctionnement physique, anxiété liée aux traitements, connaissance de la maladie, des traitements et de leurs effets, relations avec le personnel soignant et fonctionnement intellectuel. Ces 6 items spécifiques sont appréhendés, de manière similaire aux items génériques, et donc de manière différente chez l’enfant et l’adolescent. [less ▲]

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See detailEvaluation génétique des verrats Piétrain en croisement en Wallonie
Dufrasne, Marie ULiege; Jaspart, Véronique; Wavreille, José et al

Diverse speeche and writing (2010)

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See detailTrophic niche width, shift, and specialization of Dascyllus aruanus in Toliara lagoon, Madagascar
Frederich, Bruno ULiege; Lehanse, Olivier; Vandewalle, Pierre ULiege et al

in Copeia (2010), 2010(2), 218-226

Intrapopulation diet specializations may result from the use of different dietary items or foraging tactics by individuals within a single population. The damselfish, Dascyllus aruanus, is a highly site ... [more ▼]

Intrapopulation diet specializations may result from the use of different dietary items or foraging tactics by individuals within a single population. The damselfish, Dascyllus aruanus, is a highly site-attached coral reef fish living in size hierarchies among branched corals. The trophic niche width and feeding specialization of this species were explored using stable isotopes and stomach content analyses. Intra-group niche variation was mainly related to fish size. Within social groups, D. aruanus gradually shifted its foraging tactics according to size; smaller fish fed on benthic prey such as isopods and copepods, and the larger fish foraged in the water column on planktonic copepods and larger-sized prey. Group density was found to explain some variation in trophic niche characteristics; greater specialization on prey size was observed in the colony having the highest density. All members of the largest colony foraged more frequently in the water column. Knowing that planktonic copepods are more energy-rich than benthic ones, a positive group-size effect facilitating access to preferred prey is suggested. Group size and group density effects on trophic specialization did not have any impact on body condition, suggesting that the behavioral plasticity of D. aruanus in its foraging strategies permits compensation for the maintenance of body conditions. [less ▲]

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See detailIdentification des objectifs et finalités de la formation des diplômés en éducation physique. Comparaison des situations algérienne et belge francophone
Kerfes, Nabil; Cloes, Marc ULiege

in Amans-assaga, Christine; Gal-Petitfaux, Nathalie; Terral, Philippe (Eds.) et al L'intervention en sport et ses contextes institutionnels: cultures et singularité de l'action (2010, May)

Toute formation supérieure a ses principes et ses particularités visant à développer des compétences en relation avec les finalités professionnelles disponibles. La formation des éducateurs est l'une des ... [more ▼]

Toute formation supérieure a ses principes et ses particularités visant à développer des compétences en relation avec les finalités professionnelles disponibles. La formation des éducateurs est l'une des préoccupations majeures de toutes les sociétés cherchant le progrès et le développement. Ce travail se situe dans le champ de l'éducation comparée, il propose une lecture compréhensive de deux systèmes de formation dans un esprit d'ouverture et d'élargissement des connaissances. ... [less ▲]

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See detailRelations familiales internationales - l'actualité vue par la pratique
Wautelet, Patrick ULiege

Book published by Anthemis - Collection Commission Université Palais (2010)

This book which is the result of the joint efforts of 5 young authors who combine academic expertise with practical experience of international family law disputes, takes a practical approach to the most ... [more ▼]

This book which is the result of the joint efforts of 5 young authors who combine academic expertise with practical experience of international family law disputes, takes a practical approach to the most common international family law issues which may arise in Belgium. Looking at recent case law and developments in both the EU and the Hague Conference, the book offers students, practitioners and interested readers insight into the cross-border relationships between spouses and partners and between parents and children. In order to offer the reader the most practical information, the book is framed around 50 practical cases, inspired by case law and the practical experience of the authors. These cases are discussed with a view to outline the reasoning which must be followed to determine which court has jurisdiction, which law will apply and how to cope with a foreign judgment. Among the issues discussed by the authors are child abduction, cross-border adoption, foreign surrogacy agreements, recognition of foreign repudiation. In analyzing these issues, the authors take into account the latest case law on international instruments such as the Brussels IIbis Regulation and various Hague Conventions. [less ▲]

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See detailLow-rank optimization on the cone of positive semidefinite matrices
Journee, Michel ULiege; Bach, F.; Absil, P.-A. et al

in SIAM Journal on Optimization (2010), 20(5)

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See detailEnfants en et hors traitements oncologiques : analyse comparative de leur qualité de vie et de leur vécu émotionnel
Missotten, Pierre ULiege; Badot, Isabelle; Hoyoux, Claire et al

Poster (2010, May)

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See detailPetits dîners entre amis (et rivaux): prix, réseaux littéraires et stratégies de consacrants
Dozo, Björn-Olav ULiege; Lacroix, Michel

in COnTEXTES : Revue de Sociologie de la Littérature (2010), 7

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See detailComment les écrivains sont consacrés en Belgique
Dozo, Björn-Olav ULiege; Provenzano, François ULiege

in COnTEXTES : Revue de Sociologie de la Littérature (2010), 7

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