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See detailMeteorological variation in daily travel behaviour: evidence from revealed preference data from the Netherlands
Creemers, Lieve; Wets, Geert; Cools, Mario ULg

in Theoretical & Applied Climatology (in press)

This study investigates the meteorological variation in revealed preference travel data. The main objective of this study is to investigate the impact of weather conditions on daily activity participation ... [more ▼]

This study investigates the meteorological variation in revealed preference travel data. The main objective of this study is to investigate the impact of weather conditions on daily activity participation (trip motives) and daily modal choices in the Netherlands. To this end, data from the Dutch National Travel Household Survey of 2008 were matched to hourly weather data provided by the Royal Dutch Meteorological Institute and were complemented with thermal indices to indicate the level of thermal comfort and additional variables to indicate the seasonality of the weather conditions. Two multinomial logit–generalised estimation equations (MNL-GEE) models were constructed, one to assess the impact of weather conditions on trip motives and one to assess the effect of weather conditions on modal choice. The modelling results indicate that, depending on the travel attribute of concern, other factors might play a role. Nonetheless, the thermal component, as well as the aesthetical component and the physical component of weather play a significant role. Moreover, the parameter estimates indicate significant differences in the impact of weather conditions when different time scales are considered (e.g. daily versus hourly based). The fact that snow does not play any role at all was unexpected. This finding can be explained by the relatively low occurrence of this weather type in the study area. It is important to consider the effects of weather in travel demand modelling frameworks because this will help to achieve higher accuracy and more realistic traffic forecasts. These will in turn allow policy makers to make better long-term and short-term decisions to achieve various political goals, such as progress towards a sustainable transportation system. Further research in this respect should emphasise the role of weather conditions and activityscheduling attributes. [less ▲]

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See detailObservations sur l'évolution du coût du Bonus Logement pour la Wallonie
Xhignesse, Guillaume ULg

in Revue de Fiscalité Régionale et Locale (in press)

En 2011, les dépenses fiscales relatives à l'acquisition de l'habitation propre atteignaient 1.941,83 milllions d'euros dans le budget fédéral belge, soit 0,53% du PIB national. Dès l'entrée en vigueur de ... [more ▼]

En 2011, les dépenses fiscales relatives à l'acquisition de l'habitation propre atteignaient 1.941,83 milllions d'euros dans le budget fédéral belge, soit 0,53% du PIB national. Dès l'entrée en vigueur de la sixième réforme de l'Etat, ces dépenses seront à charge des budgets régionaux. Au vu des montants importants qui sont en jeu, il est nécessaire d'amorcer une réflexion sur ces aides à l'acquisition. Cette réflexion doit avant tout porter sur l'adéquation de ces aides avec les enjeux actuels et futurs en matière de logement, ainsi que sur les effets réels de ces mécanismes. Si, malgré ces interrogations, les décideurs politiques choisissent de maintenir le système en l'état, il est utile d'estimer quels seront les coûts pour les années à venir. Cette contribution se concentre sur ce dernier aspect du problème, dans le cas de la Wallonie. [less ▲]

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See detailSoutenir le développement des compétences des enseignants du supérieur par la documentation, l’investigation et le partage des pratiques en classe
Poumay, Marianne ULg; Georges, François ULg

in Dossiers des Sciences de l'Education (Les) (in press)

L’article aborde le développement professionnel des enseignants à travers un master complémentaire en pédagogie de l’enseignement supérieur. Orientée recherche, cette formation met en œuvre les principes ... [more ▼]

L’article aborde le développement professionnel des enseignants à travers un master complémentaire en pédagogie de l’enseignement supérieur. Orientée recherche, cette formation met en œuvre les principes du courant « SoTL ». Elle préconise une documentation de ses pratiques, une investigation de type scientifique de l’apprentissage des étudiants dans sa propre classe et une production de connaissance par le partage de ses avancées. Les articles de régulation rédigés à l’issue de la formation par une cohorte de dix participants montrent leur réelle inscription dans ce courant « SoTL » ; une enquête donne par ailleurs des indices d’efficacité de la formation sur ces mêmes critères à moyen terme. [less ▲]

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See detailAn algorithm recommendation for the management of knee osteoarthritis in Europe and internationally: A report from a task force of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO)
Bruyère, Olivier ULg; Cooper, C; Pelletier, JP et al

in Seminars in Arthritis & Rheumatism (in press)

Objectives: Existing practice guidelines for osteoarthritis (OA) analyze the evidence behind each proposed treatment but do not prioritize the interventions in a given sequence. The objective was to ... [more ▼]

Objectives: Existing practice guidelines for osteoarthritis (OA) analyze the evidence behind each proposed treatment but do not prioritize the interventions in a given sequence. The objective was to develop a treatment algorithm recommendation that is easier to interpret for the prescribing physician based on the available evidence and that is applicable in Europe and internationally. The knee was used as the model OA joint. Methods: ESCEO assembled a task force of 13 international experts (rheumatologists, clinical epidemiologists, and clinical scientists). Existing guidelines were reviewed; all interventions listed and recent evidence were retrieved using established databases. A first schematic flow chart with treatment prioritization was discussed in a 1-day meeting and shaped to the treatment algorithm. Fine-tuning occurred by electronic communication and three consultation rounds until consensus. Results: Basic principles consist of the need for a combined pharmacological and non-pharmacological treatment with a core set of initial measures, including information access/education, weight loss if overweight, and an appropriate exercise program. Four multimodal steps are then established. Step 1 consists of background therapy, either non-pharmacological (referral to a physical therapist for re-alignment treatment if needed and sequential introduction of further physical interventions initially and at any time thereafter) or pharmacological. The latter consists of chronic Symptomatic Slow-Acting Drugs for OA (e.g., prescription glucosamine sulfate and/or chondroitin sulfate) with paracetamol at-need; topical NSAIDs are added in the still symptomatic patient. Step 2 consists of the advanced pharmacological management in the persistent symptomatic patient and is centered on the use of oral COX-2 selective or non-selective NSAIDs, chosen based on concomitant risk factors, with intra-articular corticosteroids or hyaluronate for further symptom relief if insufficient. In Step 3, the last pharmacological attempts before surgery are represented by weak opioids and other central analgesics. Finally, Step 4 consists of end-stage disease management and surgery, with classical opioids as a difficult-to-manage alternative when surgery is contraindicated. Conclusions: The proposed treatment algorithm may represent a new framework for the development of future guidelines for the management of OA, more easily accessible to physicians. © 2014 The Authors. [less ▲]

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See detailConditioning materials with biomacromolecules: composition of the adlayer and influence on cleanability
Toure, Yetioman ULg; Genet, J. Michel; Dupont-Gillain, C. Christine et al

in Journal of Colloid and Interface Science (in press)

The influence of substrate hydrophobicity and biomacromolecules (dextran, bovine serum albumin - BSA) adsorption on the cleanability of surfaces soiled by spraying aqueous suspensions of quartz particles ... [more ▼]

The influence of substrate hydrophobicity and biomacromolecules (dextran, bovine serum albumin - BSA) adsorption on the cleanability of surfaces soiled by spraying aqueous suspensions of quartz particles (10 to 30 µm size), then dried, was investigated using glass and polystyrene as substrates. The cleanability was evaluated using radial flow cell (RFC). The surface composition was determined by X-ray photoelectron spectroscopy (XPS). The interpretation of XPS data allowed the complexity due to the ubiquitous presence of organic contaminants to be coped with, and the surface composition to be expressed in terms of both the amount of adlayer and the mass concentration of adlayer constituents. When soiled with a suspension of particles in water, glass was much less cleanable than polystyrene, which was attributed to its much lower water contact angle, in agreement with previous observations on starch soil. Dextran was easily desorbed and did not affect the cleanability. The presence of BSA at the interface strongly improved the cleanability of glass while the contact angle did not change appreciably. In contrast, soiling polystyrene with quartz particles suspended in a BSA solution instead of water did not change markedly the cleanability, while the contact angle was much lower and the aggregates of soiling particles were more flat. These observations are explained by the major role of capillary forces developed upon drying, which influence the closeness of the contact between the soiling particles and the substrate and, thereby, the adherence of particles. The capillary forces are proportional to the liquid surface tension and depend in a more complex way on contact angles of the particles and of the substrate. The dependence of cleanability on capillary forces, and in particular on the liquid surface tension, is predominant as compared with its dependence on the size and shape of the soiling aggregates, which influence the efficiency of shear forces exerted by the flowing water upon cleaning. [less ▲]

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See detailDose-dependent effect of experimental Schmallenberg virus infection in sheep
Poskin, A; Martinelle, Ludovic ULg; Mostin, L et al

in Veterinary Journal (in press)

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See detailOrganic Rankine Cycles including fluid selection
Lemort, Vincent ULg; Declaye, Sébastien ULg; Quoilin, Sylvain ULg

in Handbook of Clean Energy Systems (in press)

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ... [more ▼]

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ebullition temperature than that of water. Hence lower temperature heat sources can be exploited such as solar energy, geothermal energy and waste heat recovery from many different processes. During the design phase of an ORC system, the selection of the working fluid must be conducted in parallel with the selection and the sizing of the components (mainly the expansion machine, the pump and the heat exchangers) and with the definition of the cycle architecture. This approach allows taking into consideration all technical constraints. Relevant properties of working fluids that should be considered during their selection are listed. Major characteristics of available displacement and turbo-expander technologies are described. The impact of the pump performance on the overall performance is discussed and strategies to increase the available NPSH are proposed. Finally, improved cycle architectures are introduced. Major applications of ORC systems are described: geothermal power plants, biomass CHP plants, waste heat recovery in industry, waste heat recovery on internal combustion engines and solar power plants. All these applications differ by the nature of the heat source and heat sink, the integration of the ORC with these sources and sinks, and the range of installed capacities. These differences yield specific designs, which are described. Performance achieved by systems in operation or prototypes are presented. [less ▲]

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See detailA note on the equivalence between observed and expected information functions with polytomous IRT models
Magis, David ULg

in Journal of Educational & Behavioral Statistics (in press)

The purpose of this note is to study the equivalence of observed and expected (Fisher) information functions with polytomous item response theory (IRT) models. It is established that observed and expected ... [more ▼]

The purpose of this note is to study the equivalence of observed and expected (Fisher) information functions with polytomous item response theory (IRT) models. It is established that observed and expected information functions are equivalent for the class of divide-by-total models (including partial credit, generalized partial credit, rating scale and nominal response models), but not for the class of difference models (including the graded response and modified graded response models). Yet, observed information function remains positive in both classes. Straightforward connections with dichotomous IRT models and further implications are outlined. [less ▲]

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See detailIsolating auroral FUV emission lines using compact, broadband instrumentation
Molyneux, P.M.; Bannister, N.P.; Bunce, E.J. et al

in Planetary and Space Science (in press)

Images of auroral emissions at far ultraviolet (FUV, 122–200 nm) wavelengths are useful tools with which to study magnetospheric-ionospheric coupling, as the scattered sunlight background in this region ... [more ▼]

Images of auroral emissions at far ultraviolet (FUV, 122–200 nm) wavelengths are useful tools with which to study magnetospheric-ionospheric coupling, as the scattered sunlight background in this region is low, allowing both dayside and nightside auroras to be imaged simultaneously. The ratio of intensities between certain FUV emission lines or regions can be used to characterise the precipitating particles responsible for auroral emissions, and hence is a useful diagnostic of magnetospheric dynamics. Here, we describe how the addition of simple transmission filters to a compact broadband imager design allows far ultraviolet emission ratios to be deduced while also providing large-scale instantaneous images of the aurora. The low mass and volume of such an instrument would make it well-suited for both small satellite Earth-orbiting missions and larger outer planet missions from which it could be used to characterise the tenuous atmospheres observed at several moons, as well as studying the auroral emissions of the gas giants. We present a study to investigate the accuracy of a technique to allow emission line ratio retrieval, as applied to the OI 130.4 nm and 135.6 nm emissions at Ganymede. The ratio of these emissions provides information about the atmospheric composition, specifically the relative abundances of O and O2. Using modelled FUV spectra representative of Ganymede's atmosphere, based on observations by the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS), we find that the accuracy of the retrieved ratios is a function of the magnitude of the ratio, with the best measurements corresponding to a ratio of ∼1.3 . [less ▲]

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See detailL’auteur de la Passio sanctae Salsae a-t-il aussi écrit la Passio sancti Fabii ?
Fialon, Sabine ULg

in Meyers, Jean; Fialon, Sabine (Eds.) La Passio sanctae Salsae. Recherches sur une passion tardive d’Afrique du Nord. Avec une nouvelle édition critique d’A. M. Piredda et une traduction annotée du G.R.A.A. (in press)

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See detailDominant amphipods of Posidonia oceanica seagrass meadows display considerable trophic diversity
Michel, Loïc ULg; Dauby, Patrick ULg; Gobert, Sylvie ULg et al

in Marine Ecology (in press)

Gut content examination and trophic markers (fatty acids, stables isotopes of C and N) were combined to delineate the diet of the dominant species of amphipods from Mediterranean Posidonia oceanica ... [more ▼]

Gut content examination and trophic markers (fatty acids, stables isotopes of C and N) were combined to delineate the diet of the dominant species of amphipods from Mediterranean Posidonia oceanica seagrass meadows and to highlight trophic diversity among this community. Our results indicate that, although all dominant species heavily relied on macroalgal epiphytes, considerable interspecific dietary differences existed. Carbon stable isotope ratios notably showed that some of the amphipod species favored grazing on epiphytes from leaves or litter fragments (Apherusa chiereghinii, Aora spinicornis, Gammarus aequicauda), while others like Dexamine spiniventris preferred epiphytes from rhizomes. The remaining amphipods (Caprella acanthifera, Ampithoe helleri and Gammarella fucicola) readily consumed both groups. In addition, SIAR modeling suggested that most species had a mixed diet, and relied on several food items. Fatty acid analysis and gut contents revealed that contribution of microepiphytic diatoms and of benthic and suspended particulate organic matter to the diet of amphipods were anecdotal. None of the examined species seemed to graze on their seagrass host (low 18:2(n-6) and 18:3(n-3) fatty acids contents), but G. aequicauda partly relied on seagrass leaf detritus, as demonstrated by the lesser 13C-depletion of their tissues. Overall, our findings suggest that amphipods, because of their importance in transfers of organic matter from primary producers and detritus to higher rank consumers, are key-items in P. oceanica associated food webs. [less ▲]

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See detailJews and Christians in Late Africa : an hagiographical perspective
Fialon, Sabine ULg

in Lanfranchi, Pierluigi; Verheyden, Joseph (Eds.) Jews and Christians in Late Antiquity (titre provisoire) (in press)

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See detail« Semen est sanguis christianorum » (Apol. 50, 13). Tertullien et l'hagiographie africaine
Fialon, Sabine ULg

in Lagouanère, Jérôme; Fialon, Sabine (Eds.) Tertullianus Afer. Tertullien et la littérature chrétienne d'Afrique, IIe-VIe siècle (in press)

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See detailPET imaging analysis using a parcelation approach and multiple kernel classification
Segovia-Román, Fermín ULg; Phillips, Christophe ULg

in International Workshop on Pattern Recognition in Neuroimaging, Tübingen 4-6 June 2014 (in press)

Positron Emission Tomography (PET) is a non-invasive medical imaging modality that provides information about physiological processes. Due to its ability to measure the brain metabolism, it is widely used ... [more ▼]

Positron Emission Tomography (PET) is a non-invasive medical imaging modality that provides information about physiological processes. Due to its ability to measure the brain metabolism, it is widely used to assist the diagnosis of neurodegenerative disorders such as Alzheimer’s disease (AD) of Parkinsonism. In order to avoid the subjectivity inherent to the visual exploration of the images, several computer systems to analyze PET data were developed during the last years. However, dealing with the huge amount of information provided by PET imaging is still a challenge. In this work we present a novel methodology to analyze PET data that improves the automatic differentiation between controls and AD patients. First the images are divided into small regions or parcels, defined either anatomically, geometrically or randomly. Secondly, the accuray of each single region is estimated using a Support Vector Machine (SVM) classifier and a cross-validation approach. Finally, all the regions are assessed together using multiple kernel SVM with a kernel per region. The classifier is built so that the most discriminative regions have more weight in the final decision. This method was evaluated using a PET dataset that contained images from healthy controls and AD patients. The classification results obtained with the proposed approach outperformed two recently reported computer systems based on Principal Component Analysis and Independent Component Analysis. [less ▲]

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See detailSophistique et Philosophie: Platon, héritier de Protagoras
Gavray, Marc-Antoine ULg

Book published by Vrin (in press)

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