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See detailA new asteroseismic diagnostic for internal rotation in γ Doradus stars
Ouazzani, Rhita-Maria; Salmon, Sébastien ULg; Antoci, V. et al

in Monthly Notices of the Royal Astronomical Society (2017), 465

With four years of nearly-continuous photometry from Kepler, we are finally in a good position to apply asteroseismology to $\gamma$ Doradus stars. In particular several analyses have demonstrated the ... [more ▼]

With four years of nearly-continuous photometry from Kepler, we are finally in a good position to apply asteroseismology to $\gamma$ Doradus stars. In particular several analyses have demonstrated the possibility to detect non-uniform period spacings, which have been predicted to be directly related to rotation. In the present work, we define a new seismic diagnostic for rotation in $\gamma$ Doradus stars that are too rapidly rotating to present rotational splittings. Based on the non uniformity of their period spacings, we define the observable $\Sigma$ as the slope of the period spacing when plotted as a function of period. We provide a one-to-one relation between this observable $\Sigma$ and the internal rotation, which applies widely in the instability strip of $\gamma$ Doradus stars. We apply the diagnostic to a handful of stars observed by Kepler. Thanks to g-modes in $\gamma$ Doradus stars, we are now able to determine the internal rotation of stars on the lower main sequence, which is still not possible for Sun-like stars. [less ▲]

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See detailStrong XUV irradiation of the Earth-sized exoplanets orbiting the ultracool dwarf TRAPPIST-1
Wheatley, Peter J.; Louden, Tom; Bourrier, Vincent et al

in Monthly Notices of the Royal Astronomical Society (2017), 465

We present an XMM-Newton X-ray observation of TRAPPIST-1, which is an ultracool dwarf star recently discovered to host three transiting and temperate Earth-sized planets. We find the star is a relatively ... [more ▼]

We present an XMM-Newton X-ray observation of TRAPPIST-1, which is an ultracool dwarf star recently discovered to host three transiting and temperate Earth-sized planets. We find the star is a relatively strong and variable coronal X-ray source with an X-ray luminosity similar to that of the quiet Sun, despite its much lower bolometric luminosity. We find L_x/L_bol=2-4x10^-4, with the total XUV emission in the range L_xuv/L_bol=6-9x10^-4. Using a simple energy-limited model we show that the relatively close-in Earth-sized planets, which span the classical habitable zone of the star, are subject to sufficient X-ray and EUV irradiation to significantly alter their primary and perhaps secondary atmospheres. Understanding whether this high-energy irradiation makes the planets more or less habitable is a complex question, but our measured fluxes will be an important input to the necessary models of atmospheric evolution. [less ▲]

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See detailXMM-Newton : en route vers une autre décennie de découvertes
Rauw, Grégor ULg

Article for general public (2017)

Au mois de décembre 2016, cela faisait 17 ans que XMM-Newton fut lancé par une fusée Ariane V. Equipé de ses trois modules miroirs comportant chacun 58 miroirs imbriqués les uns dans les autres, XMM ... [more ▼]

Au mois de décembre 2016, cela faisait 17 ans que XMM-Newton fut lancé par une fusée Ariane V. Equipé de ses trois modules miroirs comportant chacun 58 miroirs imbriqués les uns dans les autres, XMM-Newton est à l’affût de l’émission X de sources cosmiques de tout genre. Malgré sa longévité, XMM-Newton reste à ce jour un des observatoires les plus sollicités au monde. Chaque année, les astrophysiciens proposent des programmes d’observation qui totalisent à peu près 6 fois le temps d’observation disponible! La compétition pour les observations avec XMM est donc très rude. Et a priori cela pourrait continuer encore comme cela pendant quelques années. De fait, les réserves de carburant et la performance des panneaux solaires indiquent que la mission pourrait encore fonctionner au moins 10 ans si les budgets le permettent1! [less ▲]

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See detailAutomated multimodal volume registration based on supervised 3D anatomical landmark detection
Vandaele, Rémy ULg; Lallemand, François ULg; MARTINIVE, Philippe ULg et al

Conference (2017, February)

Landmark detectors are learned independantly in the two imaging modalities using Extremely Randomized Trees and multi-resolution voxel windows. A least-squares fitting algorithm is then used for rigid ... [more ▼]

Landmark detectors are learned independantly in the two imaging modalities using Extremely Randomized Trees and multi-resolution voxel windows. A least-squares fitting algorithm is then used for rigid registration based on the landmark positions as predicted by these detectors in the two imaging modalities. Experiments are carried out with this method on a dataset of pelvis CT and CBCT scans related to 45 patients. On this dataset, our fully automatic approach yields results very competitive with respect to a manually assisted stateof- the-art rigid registration algorithm. [less ▲]

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See detailThe importance of open data and software: Is energy research lagging behind?
Pfenninger, Stefan; DeCariolis, Joseph; Hirth, Lion et al

in Energy Policy (2017)

Energy policy often builds on insights gained from quantitative energy models and their underlying data. As climate change mitigation and economic concerns drive a sustained transformation of the energy ... [more ▼]

Energy policy often builds on insights gained from quantitative energy models and their underlying data. As climate change mitigation and economic concerns drive a sustained transformation of the energy sector, transparent and well-founded analyses are more important than ever. We assert that models and their associated data must be openly available to facilitate higher quality science, greater productivity through less duplicated effort, and a more effective science-policy boundary. There are also valid reasons why data and code are not open: ethical and security concerns, unwanted exposure, additional workload, and institutional or personal inertia. Overall, energy policy research ostensibly lags behind other fields in promoting more open and reproducible science. We take stock of the status quo and propose actionable steps forward for the energy research community to ensure that it can better engage with decision-makers and continues to deliver robust policy advice in a transparent and reproducible way. [less ▲]

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See detailApproximate Bayes Optimal Policy Search using Neural Networks
Castronovo, Michaël ULg; François-Lavet, Vincent ULg; Fonteneau, Raphaël ULg et al

in Proceedings of the 9th International Conference on Agents and Artificial Intelligence (ICAART 2017) (2017, February)

Bayesian Reinforcement Learning (BRL) agents aim to maximise the expected collected rewards obtained when interacting with an unknown Markov Decision Process (MDP) while using some prior knowledge. State ... [more ▼]

Bayesian Reinforcement Learning (BRL) agents aim to maximise the expected collected rewards obtained when interacting with an unknown Markov Decision Process (MDP) while using some prior knowledge. State-of-the-art BRL agents rely on frequent updates of the belief on the MDP, as new observations of the environment are made. This offers theoretical guarantees to converge to an optimum, but is computationally intractable, even on small-scale problems. In this paper, we present a method that circumvents this issue by training a parametric policy able to recommend an action directly from raw observations. Artificial Neural Networks (ANNs) are used to represent this policy, and are trained on the trajectories sampled from the prior. The trained model is then used online, and is able to act on the real MDP at a very low computational cost. Our new algorithm shows strong empirical performance, on a wide range of test problems, and is robust to inaccuracies of the prior distribution. [less ▲]

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See detailVoyage[s] à travers le thymus
Geenen, Vincent ULg

in Science et Culture (2017), (465), 14-15

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See detailA propos de l'émotion créatrice : vie, institution et histoire dans Les Deux Sources
Caeymaex, Florence ULg

in François, A.; Riquier, C. (Eds.) Bergson, la morale, les émotions (Annales bergsoniennes VIII) (2017)

Ce chapitre montre la centralité de l'émotion dans la théorie sociale de Bergson, au-delà de sa théorie psychologique. L'émotion n'est cependant pas seulement un phénomène sociologique, logé au fond des ... [more ▼]

Ce chapitre montre la centralité de l'émotion dans la théorie sociale de Bergson, au-delà de sa théorie psychologique. L'émotion n'est cependant pas seulement un phénomène sociologique, logé au fond des institutions sociales et morales ; en associant l'émotion, non au registre de la sensibilité passive, mais à celui d'une sensibilité active et créatrice, il suggère qu'elle est à la source des grandes transformations morales sans lesquelles la vie humaine ne connaîtrait pas de temporalité historique à proprement parler. [less ▲]

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See detailRelativité générale
De Rop, Yves ULg

Learning material (2017)

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See detailCombattre le travail des enfants? Politiques et acteurs d'une lutte controversée au Burkina Faso
Wouango, Joséphine ULg

Book published by L'Harmattan (2017)

Depuis le début des années 1990, l’intérêt de la communauté internationale pour l’abolition du travail des enfants dans les pays du Sud est redevenu grandissant. La Convention internationale des droits de ... [more ▼]

Depuis le début des années 1990, l’intérêt de la communauté internationale pour l’abolition du travail des enfants dans les pays du Sud est redevenu grandissant. La Convention internationale des droits de l’enfant de 1989 constitue un des fondements de ce regain d’intérêt pour protéger les enfants et leur assurer la jouissance de leurs droits. La manière dont ce nouvel objectif, à la fois politique et social, est transposé, réapproprié et mis en pratique au Burkina Faso constitue le coeur de la réflexion développée dans cet ouvrage. La lutte contre le travail des enfants est analysée, d’abord, dans une perspective socio-historique. Ensuite, les politiques publiques contemporaines et l’action publique qui sous-tend leur mise en oeuvre sont décryptées. Enfin, ces formes publiques de protection de l’enfant travailleur sont confrontées aux vécus d’enfants qui travaillent dans les mines, les carrières et dans la vente ambulante au Burkina Faso. Cet ouvrage montre qu’il est important de mieux comprendre la place précise du travail dans la vie des enfants travailleurs (et de leurs familles) afin d’élaborer des politiques et des actions durables pour les aider. [less ▲]

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See detailThe recent increase of atmospheric methane from 10 years of ground-based NDACC FTIR observations since 2005
Bader, Whitney ULg; Bovy, Benoît ULg; Conway, Stephanie et al

in Atmospheric Chemistry and Physics (2017)

Changes of atmospheric methane total columns (CH4/ since 2005 have been evaluated using Fourier transform infrared (FTIR) solar observations carried out at 10 ground-based sites, affiliated to the Network ... [more ▼]

Changes of atmospheric methane total columns (CH4/ since 2005 have been evaluated using Fourier transform infrared (FTIR) solar observations carried out at 10 ground-based sites, affiliated to the Network for Detection of Atmospheric Composition Change (NDACC). From this, we find an increase of atmospheric methane total columns of 0.31±0.03 %/year (2-sigma level of uncertainty) for the 2005–2014 period. Comparisons with in situ methane measurements at both local and global scales show good 10 agreement. We used the GEOS-Chem chemical transport model tagged simulation, which accounts for the contribution of each emission source and one sink in the total methane, simulated over 2005–2012. After regridding according to NDACC vertical layering using a conservative 15 regridding scheme and smoothing by convolving with respective FTIR seasonal averaging kernels, the GEOS-Chem simulation shows an increase of atmospheric methane total columns of 0.35±0.03 %/year between 2005 and 2012, which is in agreement with NDACC measurements over the same time period (0.30±0.04 %/year, averaged over 10 stations). Analysis of the GEOS-Chem-tagged simulation allows us to quantify the contribution of each tracer to the global methane change since 2005. We find that natural sources such as wetlands and biomass burning contribute to the interannual variability of methane. However, anthropogenic emissions, such as coal mining, and gas and oil transport and exploration, which are mainly emitted in the Northern Hemisphere and act as secondary contributors to the global budget of methane, have played a major role in the increase of atmospheric methane observed since 2005. Based on the GEOS-Chem-tagged simulation, we discuss possible cause(s) for the increase of methane since 2005, which is still unexplained. [less ▲]

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See detailSur l'évaluation de compétences en mathématiques
Bair, Jacques ULg

E-print/Working paper (2017)

Ce document comprend deux parties. Tout d’abord, un texte est consacré à des généralités sur la mesure de compétences, ainsi qu’à la présentation, illustrée par des exemples concrets, de différents types ... [more ▼]

Ce document comprend deux parties. Tout d’abord, un texte est consacré à des généralités sur la mesure de compétences, ainsi qu’à la présentation, illustrée par des exemples concrets, de différents types d’échelles (universelle, descriptive, globale) et de grilles d’évaluation. Enfin, ce travail se termine par la reproduction de diapositives (initialement réalisées à l’aide du logiciel Power Point) préparées pour accompagner une leçon sur l’évaluation ; l’exposé oral correspondant a été donné, dans le cadre de la FOPED (Formation Pédagogique), à plusieurs cohortes de stagiaires en mathématiques à l’Université du Luxembourg. [less ▲]

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See detailDrafting Choice of Law and Choice of Court Provisions under the EU Succession Regulation
Wautelet, Patrick ULg

in Conseil des Notariats de l'Union européenne (Ed.) L'europe pour les notaires - les notaires pour l'Europe - Formation 2015-2017 (2017)

This paper gives an overview of the possibilities offered by the European Succession Regulation (650/2012) to select the applicable law and the competent court. After a general overview, the attention ... [more ▼]

This paper gives an overview of the possibilities offered by the European Succession Regulation (650/2012) to select the applicable law and the competent court. After a general overview, the attention turns to specific topics such as the elements which need to be included in a choice of law provision, the impact of the existence of multiple nationalities, the choice of law in multi-jurisdictional countries, the impact of 'renvoi', and the relationship with third states. [less ▲]

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See detailDescription of patients consulting the voice clinic regarding gender, age, occupational status, and diagnosis
Remacle, Angélique ULg; Petitfils, Cloé; FINCK, Camille ULg et al

in European Archives of Oto-rhino-laryngology : Official Journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) (2017), 274(3), 1567-1576

Purpose. To describe the gender, age, occupational status and diagnosis of dysphonic patients. Method. We retrospectively analyzed the medical records of 1079 patients examined at the Voice clinic of the ... [more ▼]

Purpose. To describe the gender, age, occupational status and diagnosis of dysphonic patients. Method. We retrospectively analyzed the medical records of 1079 patients examined at the Voice clinic of the University hospital of Liège in French-speaking Belgium. Results. Overall, seven out of 10 patients who attended the voice clinic for dysphonia were females. The patients’ ages ranged from 4 to 93 (mean=43.5). Females predominantly consulted at the age of 54 and males at the age of 9. Regarding the occupational status, workers represented more than half of our patients (53%), while 11.2% were unemployed, 15.4% were students, and 19.9% were retired. Regarding the diagnoses of the 1079 patients, nodules were the most common pathologies (n=182, 16.9% of the patients), prevailing in females (n=142, 18.8% of the females), encountered in 16.8% of the workers and 42.8% of the students consulting the voice clinic. Following nodules, laryngeal mobility disorders were diagnosed in 16.4% of the patients (n=177), mainly females (n=115), and was the most frequent diagnosis in retirees (n=75, 34.9%). Conclusions. The majority of the patients consulting the voice clinic for dysphonia were adult females, in their workforce, diagnosed with vocal nodules. The identification of the patients’ characteristics and diagnoses is important to develop treatments and prevention of dysphonia, estimate their costs, and allow comparisons across referral centers. [less ▲]

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See detailMontée des eaux : Un nouveau modèle de simulation climatique
Wyard, Coraline ULg; Fettweis, Xavier ULg

Article for general public (2017)

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See detailPhenotypes to genetically reduce greenhouse gas emissions in dairying
de Haas, Yvette; Pszczola, Marcin; Soyeurt, Hélène ULg et al

in Journal of Dairy Science (2017), 100(2), 855-870

Phenotypes have been reviewed to select for lower-emitting animals in order to decrease the environmental footprint of dairy cattle products. This includes direct selection for breath measurements, as ... [more ▼]

Phenotypes have been reviewed to select for lower-emitting animals in order to decrease the environmental footprint of dairy cattle products. This includes direct selection for breath measurements, as well as indirect selection via indicator traits such as feed intake, milk spectral data, and rumen microbial communities. Many of these traits are expensive or difficult to record, or both, but with genomic selection, inclusion of methane emission as a breeding goal trait is feasible, even with a limited number of registrations. At present, methane emission is not included among breeding goals for dairy cattle worldwide. There is no incentive to include enteric methane in breeding goals, although global warming and the release of greenhouse gases is a much-debated political topic. However, if selection for reduced methane emission became a reality, there would be limited consensus as to which phenotype to select for: methane in liters per day or grams per day, methane in liters per kilogram of energy-corrected milk or dry matter intake, or a residual methane phenotype, where methane production is corrected for milk production and the weight of the cow. We have reviewed the advantages and disadvantages of these traits, and discuss the methods for selection and consequences for these phenotypes. [less ▲]

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