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See detailModeling risk and expected returns in finance and macroeconomics
Lejeune, Thomas ULg

Doctoral thesis (2014)

This doctoral dissertation contributes to the modeling of risk and expected returns in the fields of finance and macroeconomics. On the finance side, the thesis proposes a portfolio choice model and a ... [more ▼]

This doctoral dissertation contributes to the modeling of risk and expected returns in the fields of finance and macroeconomics. On the finance side, the thesis proposes a portfolio choice model and a risk-return setup that simultaneously deal with agents’ unknown utility function, incomplete knowledge of financial return distributions, departures from the Gaussian distribution (i.e. asymmetry and fat-tail risks), investment horizons and investors’ objectives in terms of expected returns. On the macroeconomic side, the objective is to deliver a comprehensive picture of the financial sector in a general equilibrium framework, which accommodates the heterogeneity of behaviors within financial intermediaries. The first part of the thesis introduces an innovative risk measure, risk horizon, with reference to the speed of convergence of an asset’s mean return to its expectation. This measure is a keystone to a general framework for characterizing investors’ behavior in portfolio selection, which takes into account consideration for volatility, asymmetric and fat-tail risk, a trade-off between downside and upside potential of financial assets, and the timing and probability of deviations from expected returns. The risk horizon framework opens up the way to the identification of forward-looking determinants of market sentiment that includes, among others, the expected market and credit returns. The last part of the thesis is devoted to a macroeconomic model with heterogeneous and financially constrained intermediaries. An analysis of endogenous risk mechanisms when traditional and shadow banking interact is carried out. The model sheds light on the importance of relative leverage behaviors in the amplification of adverse shocks in the economy. [less ▲]

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See detailSaturn’s elusive nightside polar arc
Radioti, Aikaterini ULg; Grodent, Denis ULg; Gérard, Jean-Claude ULg et al

in Geophysical Research Letters (2014)

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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 (2014), 103

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 detailSpectral mapping of the FUV Jovian aurora and electron energy distribution
Gérard, Jean-Claude ULg; Bonfond, Bertrand ULg; Grodent, Denis ULg et al

Conference (2014, September)

Observations have been made with the Hubble Space Telescope in the timetag mode using the STIS long slit. During the 40 min of the observations, the slit spatially scanned the polar regions to build ... [more ▼]

Observations have been made with the Hubble Space Telescope in the timetag mode using the STIS long slit. During the 40 min of the observations, the slit spatially scanned the polar regions to build spectral maps of the jovian aurora. The emission is composed of the HI Lyman-alpha line and the H2 Lyman and Werner bands. The shorter wavelengths are partly absorbed by the methane layer overlying the bulk of the auroral emission. Since the CH4 absorption cross section drastically drops above 140 nm, the longer wavelengths are not absorbed and the intensity directly reflects the precipitated energy flux carried by the electrons. Maps of the intensity ratio of the two spectral regions will be presented, together with the associated auroral electron energy. These values will be compared with those expected from current magnetosphere-ionosphere model. They will provide input into 3-D modeling of the auroral heat source into the high-latitude Jovian upper atmosphere. [less ▲]

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See detailSTARS of HEAVEN - interview ( Chicago, Juin 2014)
Sacré, Robert ULg

in ABS Magazine (2014), (n° 43), 28-32

Interview des membres des Stars of Heaven ; photos

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See detailCROSSROADS le magazine sonore des musiques africaines-amé&ricaines
Sacré, Robert ULg

Diverse speeche and writing (2014)

Programme radio hebdomadaire consacré aux musiques africaines-américaines podcasts : wwxw.mixcloud.com/robertsacre9 - www.equinoxefm.be

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See detailAdaptation interculturelle et validation du questionnaire VISA-A en français
Oppong-Kyei, Julian; Bruyère, Olivier ULg; Delvaux, François ULg et al

in 7ème Congrès National SFMES & SFTS 2014 (2014, September)

Introduction La tendinopathie d’Achille, dont la discipline athlétique implique une grosse activité de course à pied, représente une source de douleurs et de handicap. Cette pathologie fait actuellement l ... [more ▼]

Introduction La tendinopathie d’Achille, dont la discipline athlétique implique une grosse activité de course à pied, représente une source de douleurs et de handicap. Cette pathologie fait actuellement l'objet de nouvelles découvertes sur le plan de la physiopathologie permettant l'exploration de nouvelles pistes thérapeutiques. Dans le cadre de telles études, des échelles d’évaluation sont utilisées afin d'évaluer des phénomènes subjectifs ou complexes tels la douleur, la qualité de vie, le handicap, etc. Elles sont généralement composées de plusieurs items dont la cotation est combinée en un score global ou des sous scores dimensionnels. La majorité des échelles algo-fonctionnelles sont développés dans des pays anglophones et sont par conséquence uniquement pertinents pour des sujets parlant l’anglais. Ceci est la cas pour le Victorian Institute of Sports Assessment–Achilles (VISA-A), un questionnaire développé dans le but d'évaluer la sévérité des symptômes de la tendinopathie achilléenne. L’intérêt de ce mémoire est donc de valider une version française fiable de ce questionnaire. Matériel et méthode La traduction et l’adaptation interculturelle du VISA-A ont été réalisées selon les recommandations internationales (Guidelines for the Process of Cross-Cultural Adaptation of Self-Report Measures). Ce processus s'est déroulé en 6 étapes : traductions initiales, synthèse des traductions, traduction de retour vers la langue d’origine, comité expert, test de la version pré-finale et approbation du comité expert. La version française finale obtenue fut ensuite l’objet d’une évaluation de certaines propriétés psychométriques telles que la fidélité test-retest, la cohérence interne, la validité de construit et les effets plancher et plafond. Pour ces évaluations, 116 sujets furent recruté et répartis en 3 groupes : un groupe de sujets pathologiques principalement recrutés parmi les patients du Centre Hospitalier Universitaire de Liège (31), un groupe de sujets asymptomatiques (22) et un groupe de sportifs à risque (63). Tous ces sujets durent également répondre à un questionnaire supplémentaire, le Medical Outcomes Survey Short Form 36 questionnaire (SF-36) pour la validité de construit. L'ensemble des participants ont été recrutés au sein de la province de Liège. Résultats Aucun sujets ne présenta de difficultés à comprendre le questionnaire suite au test de la version pré-finale. Les différents membres du comité expert se montrèrent satisfait de la version finale et donnèrent donc leur approbation. La moyenne des scores obtenus dans le groupe pathologique est de 59 (± 18), celle du groupe sain est de 99 (± 1) et celle du groupe à risque est de 94 (± 7). Aucun effet plancher ou plafond n'a pu être observer lors de l'évaluation des propriétés psychométriques du VISA-A (dans le groupe pathologique). Les corrélations entre le VISA-A et certaines mesures divergentes du SF-36 semblent être faibles. Les coefficients de corrélation mesurés entre les scores du VISA-A et les items convergents du SF-36 paraissent être élevé. Conclusion La version française du VISA-A est donc être un questionnaire compréhensible, fiable et adapté aux patients francophones souffrant d'une tendinopathie d'Achille. [less ▲]

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See detailAdaptation interculturelle et validation du questionnaire VISA-P en français
Oppong-Kyei, Julian; Bruyère, Olivier ULg; Delvaux, François ULg et al

in 7ème Congrès National SFMES & SFTS 2014 (2014, September)

Introduction La tendinopathie patellaire est une affection musculo-squelettique très fréquentes chez le sportif et la plus fréquente au niveau du genou. Elle affecte le plus souvent des disciplines qui ... [more ▼]

Introduction La tendinopathie patellaire est une affection musculo-squelettique très fréquentes chez le sportif et la plus fréquente au niveau du genou. Elle affecte le plus souvent des disciplines qui nécessitent soit des impulsions et des sauts soit un travail important du quadriceps. Le Victorian Institute of Sports Assessment–Patellar (VISA-P) est un questionnaire permettant d’évaluer les symptômes et leurs retentissements sur les activités physiques quotidiennes et sportives de la tendinopathie patellaire (Jumper’s knee). Comme la plus part des questionnaires de ce type, le VISA-P fut originalement développé pour des patients anglophones et n'est donc pas adapté à une population francophone. En conséquence, l'objectif de cette étude sera de traduire, adapter et valider une version française fiable du VISA-P et d'en évaluer ses propriétés psychométriques. Matériel et méthode La traduction et l’adaptation interculturelle du VISA-P ont été réalisées selon les recommandations internationales (Guidelines for the Process of Cross-Cultural Adaptation of Self-Report Measures). Ce processus s'est déroulé en 6 étapes : traductions initiales, synthèse des traductions, traduction de retour vers la langue d’origine, comité expert, test de la version pré-finale et approbation du comité expert. La version française finale obtenue fut ensuite l’objet d’une évaluation de certaines propriétés psychométriques telles que la fidélité test-retest, la cohérence interne, la validité de construit et les effets plancher et plafond. Nonante-deux sujets furent recruté au total afin de tester ces propriétés psychométriques. Trois groupes de sujets furent utilisés pour répondre conjointement aux VISA-P et à un questionnaire supplémentaire, le Medical Outcomes Survey Short Form 36 questionnaire (SF-36) pour la validité de construit : un groupe de sujets pathologiques principalement recrutés parmi les patients du Centre Hospitalier Universitaire de Liège (28), un groupe de sujets asymptomatiques (22) et un groupe de sportifs à risque recrutés dans divers clubs sportif (42). L'ensemble des participants ont été recrutés au sein de la province de Liège. Résultats Aucun sujet ne présenta de grosses difficultés à comprendre le questionnaire suite au test de la version pré-finale. Les différents membres du comité expert se montrèrent satisfait de la version finale et donnèrent donc leur approbation. La moyenne des scores obtenu est de 53 (± 17) pour le groupe pathologique, 99 (± 2) pour le groupe sain et 86 (± 14) pour le groupe à risque. Les corrélations entre le VISA-P et certaines mesures divergentes du SF-36 semblent donner des résultats faibles. Les coefficients de corrélation mesurés entre les scores du VISA-P et les items convergents du SF-36 paraissent être élevés. Aucun effet plancher ou plafond n'a pu être observer lors de l'évaluation des propriétés psychométriques du VISA-P dans le groupe pathologique. Conclusion La version française du VISA-P est donc être un questionnaire compréhensible, fiable et adapté aux patients francophones souffrant d'une tendinopathie patellaire supérieur. [less ▲]

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See detailEpidémiologie de la lithiase urinaire en Province de Liège
GADISSEUR, Romy ULg; Castiglione, Vincent ULg; JOURET, François ULg et al

in Néphrologie & Thérapeutique (2014, September), 10(5), 270

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See detailJupiter's equatorward auroral features : Possible signature of magnetospheric injections
Dumont, Maïté ULg; Grodent, Denis ULg; Radioti, Aikaterini ULg et al

Conference (2014, September)

We investigate the characteristics of ultraviolet auroral features located equatorward of the main emission appearing in the Hubble Space Telescope (HST) images obtained in 2000-2007. Several properties ... [more ▼]

We investigate the characteristics of ultraviolet auroral features located equatorward of the main emission appearing in the Hubble Space Telescope (HST) images obtained in 2000-2007. Several properties of the auroral emissions are analyzed. The mapped radial position and System III longitude of the observed auroral features are in good agreement with those of the injections observed in the equatorial plane by Galileo. Finally, we discuss the processes causing auroral signatures of injections. This comparative study demonstrates that the structures under study are most probably related to magnetospheric injections and sheds light to the mechanism involved in the magnetosphere-ionosphere dynamics. [less ▲]

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See detailUn univers de perles - Le pendentif galactique
Nazé, Yaël ULg

Article for general public (2014)

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See detailHow much time does it take for "experience design" to unfold?
Elsen, Catherine ULg; Leclercq, Pierre ULg

in Benz, Peter (Ed.) Designing Experiences: Positions and Approaches. (2014)

This paper specifically focuses on one aspect of the experience design process, sometimes even stressed as one if its shortcomings: the time it takes to properly gain insights about possible real-life ... [more ▼]

This paper specifically focuses on one aspect of the experience design process, sometimes even stressed as one if its shortcomings: the time it takes to properly gain insights about possible real-life experiences of proximal or distal end-users. In the process of making sense of sometimes conflicting viewpoints found in the literature about timing and its possible impact on design processes and outcomes, this paper compares four distinct settings and addresses the following research questions: • How “time-framing” the design process possibly filters (positively or negatively) the awareness designers have about end-users; • How the experimental protocols, their inherent limitations and artificialities, do shape the designers’ involvement in the process of designing for an end-user’s experience. Results put techniques for «disciplined creativity», such as brainstorming or analogies, front-to-front with more reflective approaches that unfold over more time, and discuss respective but complementary added values of both. [less ▲]

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See detailBioaccumulation of polybrominated diphenyl ethers (PBDEs) in Gammarus pulex: Relative importance of different exposure routes and multipathway modeling
Lebrun, Jérémie; Leroy, Delphine; Giusti, Arnaud ULg et al

in Aquatic Toxicology (2014), 154

Characterizing the exposure routes of an organism and its ability to regulate accumulated contaminants is a crucial step toward developing a biomonitor. To date, very little data are available on the ... [more ▼]

Characterizing the exposure routes of an organism and its ability to regulate accumulated contaminants is a crucial step toward developing a biomonitor. To date, very little data are available on the bioaccumulation kinetics of PBDEs in freshwater biota. This study aims at investigating the potential use of a litter-degrader widely distributed in European freshwaters, Gammarus pulex, as an indicator of exposure to PBDEs. In aquatic microcosms, gammarids were exposed to a mixture of brominated congeners (BDE-28, 47, 66, 85, 99, 100, 153, 154 and 183) to assess their ability to bioconcentrate PBDEs. Results show that all tested congeners are highly internalized by G. pulex and uptake rates of PBDEs are closely related to their partition coefficients (Kow). The determination of the elimination rate of BDE-47, the congener most readily accumulated by gammarids, indicated that metabolism and excretion of this congener are low in G. pulex, which argues in favor of its use as a quantitative biomonitor. Finally, bioaccumulation experiments were performed using contaminated leaves to determine the relative importance of dietary uptake in the contamination of gammarids. Even though water is the preeminent exposure route, a significant uptake of BDE-47 through food was observed (27%). We propose a biodynamic model that takes into account both exposure routes to describe BDE-47 bioaccumulation. This study supports the use of this ubiquitous amphipod as an early warning monitor of the bioavailable contamination of freshwaters by PBDEs. [less ▲]

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See detailBiointerface multiparametric investigation of intraocular lens acrylic materials
Bertrand, Virginie ULg; Bozukova, Dimitriya; Svaldo Lanero, Tiziana et al

in Journal of Cataract & Refractive Surgery (2014), 40(9), 1536-1544

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See detailNIR interferometric observations of massive hierarchical triple systems: Tr16-104 and HD150136
Gosset, Eric ULg; Le Bouquin, Jean-Baptiste; Absil, Olivier ULg et al

in de Grijs, Richard (Ed.) Binary Systems: their Evolution and Environments (2014, September)

We report on an observational astrometric study of the orbit of the tertiary stars in two massive hierarchical triple systems. The work is complemented by radial velocity data with the aim of deriving the ... [more ▼]

We report on an observational astrometric study of the orbit of the tertiary stars in two massive hierarchical triple systems. The work is complemented by radial velocity data with the aim of deriving the full 3D orbit and constraints on the orbital planes. This is the first report of the tertiary star's detection for Tr16-104. The work is a natural extension of the search for binaries among massive O-stars. The basic motivation of the study of hierarchical triple systems is the determination of the masses of the individual components and the derivation of the relative orientation of the two orbital planes, with the ultimate aim of understanding the related star formation processes. [less ▲]

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See detailThe Double-Sarcophagus of Hierapytna (Creta). A Reassessment
Veymiers, Richard ULg

Conference (2014, September)

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See detailLes objectifs de la formation des soignants en Education Thérapeutique du Patient : une proposition
Pétré, Benoît ULg; Guillaume, Michèle ULg; LEGRAND, Catherine et al

Conference (2014, September)

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