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See detailPrecision Asteroseismology of the Pulsating White Dwarf GD 1212 Using a Two-wheel-controlled Kepler Spacecraft
Hermes, J.J.; Charpinet, Stéphane; Barclay, Thomas et al

in Astrophysical Journal (2014), 789

We present a preliminary analysis of the cool pulsating white dwarf (WD) GD 1212, enabled by more than 11.5 days of space-based photometry obtained during an engineering test of the two-reaction-wheel ... [more ▼]

We present a preliminary analysis of the cool pulsating white dwarf (WD) GD 1212, enabled by more than 11.5 days of space-based photometry obtained during an engineering test of the two-reaction-wheel-controlled Kepler spacecraft. We detect at least 19 independent pulsation modes, ranging from 828.2-1220.8 s, and at least 17 nonlinear combination frequencies of those independent pulsations. Our longest uninterrupted light curve, 9.0 days in length, evidences coherent difference frequencies at periods inaccessible from the ground, up to 14.5 hr, the longest-period signals ever detected in a pulsating WD. These results mark some of the first science to come from a two-wheel-controlled Kepler spacecraft, proving the capability for unprecedented discoveries afforded by extending Kepler observations to the ecliptic. [less ▲]

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See detailQuel système d'évaluations génétiques pour les verrats Piétrain en Wallonie
Dufrasne, Marie ULg; Piedboeuf, Maureen; Wavreille, José et al

Article for general public (2014)

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See detailValidation of a new automatic drowsiness quantification system for drivers
Wertz, Jérôme ULg; François, Clémentine ULg; Verly, Jacques ULg

Poster (2014, July)

Drowsiness is a major cause of various types of accidents, and particularly of driving accidents. Scientific studies report that drowsiness would be responsible for 20 to 30% of driving accidents ... [more ▼]

Drowsiness is a major cause of various types of accidents, and particularly of driving accidents. Scientific studies report that drowsiness would be responsible for 20 to 30% of driving accidents. Drowsiness can result from, among others, sleep deprivation, sleep disorders, alcohol, some medications, or performing a monotonous task. While all persons are likely to be drowsy at some point during the day, some persons are more prone than others to being drowsy at almost any time of the day; e.g. 6 to 11% of the population suffers from severe chronic excessive daytime sleepiness. Three main classes of methods can be used to characterize the level of drowsiness of a driver without disturbing him. These classes are respectively related to vehicle behavior (e.g. via lateral movements), driver behavior (e.g. via steering wheel movements), and driver physiological state (e.g. via eye movements). Since drowsiness is a physiological state, it seems particularly meaningful to use physiology-based methods to characterize it. Among these, the most significant ones rely on polysomnography and/or oculography. Polysomnography is viewed by some practitioners as the reference in the domain, but it is very sensitive to artifacts, and it is not very practical for use while driving. Ocular parameters are recognized to be good and reliable physiological indicators of drowsiness, and, thus, oculography seems to be the most sensible way to characterize drowsiness in practice. We have thus developed an experimental, fully automatic drowsiness monitoring system (software/algorithms) based on the physiological state of a person. This system uses ocular parameters extracted from images of the eye (i.e. photooculography) to determine a level of drowsiness on a continuous numerical scale from 0 to 10, with 0 corresponding to "very awake" (or "very vigilant") and 10 to "very drowsy". The ultimate goal of this system is to prevent drowsiness-related accidents for driving and other applications. The reported study shows that our system exhibits promising capability for road safety. Fourteen healthy volunteers (7 M, 7 F, mean age 23.7, range 21-33 years) participated in an experiment in a driving simulator, where they were asked to perform three driving sessions/runs (two of 45 minutes and one of 60 minutes) in different sleep-deprivation conditions (with up to 28 hours of complete sleep deprivation). During each session, we recorded both a high frame rate video of one eye and a set of driving parameters. Subsequently, for each successive minute in the session, we used our algorithms to extract ocular parameters from the video images and to produce a level of drowsiness, and we computed the standard deviation of lateral position (SDLP) from the driving parameters. The results show (1) that the (computed) SDLP increases when the (computed) level of drowsiness increases, and (2) that the level of drowsiness increases when the level of sleep deprivation increases. These results indicate that our algorithms for producing a level of drowsiness work in a meaningful way. The experiment protocol was approved by the Ethics Committee of our university. [less ▲]

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See detailAn Econometric Analysis of Homeownership Determinants in Belgium
Xhignesse, Guillaume ULg; Bianchet, Bruno ULg; Cools, Mario ULg et al

in Lecture Notes in Computer Science (2014, July), 8581

In market economies, homeownership is associated with positive ex- ternalities. Increasing the levels of homeownership has been an objective of governments for the last decades. The analysis of the ... [more ▼]

In market economies, homeownership is associated with positive ex- ternalities. Increasing the levels of homeownership has been an objective of governments for the last decades. The analysis of the determinants of tenure sta- tus provides information to this end. This paper proposes an econometric analysis of housing tenure in Belgium. We review the main variables that have been considered in the literature as influencing housing tenure, after what we estimate a logit model. We observe a strong influence of income and age on the probability of homeownership. Couple relationship and the presence of dependent children have a positive influence, but this influence is less significant. Urban location is associated with lower probability of homeownership, compared with other areas. Our observations follow the trends described for other countries in the literature. [less ▲]

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See detailSynthesis of Pt/Carbon Xerogel Electrocatalysts for Proton Exchange Membrane Fuel Cells (PEMFC): Effect of the Reduction Procedure
Zubiaur, Anthony ULg; Chatenet, Marian; Maillard, Frédéric et al

Conference (2014, July)

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See detailDesign of Pt/carbon xerogel catalysts for PEM fuel cells
Job, Nathalie ULg; Lambert, Stéphanie ULg; Zubiaur, Anthony ULg et al

Conference (2014, July)

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See detailSynthesis of Pt/Carbon Xerogel Electrocatalysts for PEM Fuel Cells by the Multiple SEA Method
Zubiaur, Anthony ULg; Chatenet, Marian; Maillard, Frédéric et al

Poster (2014, July)

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See detailMars nightglow review
Stiepen, Arnaud ULg

Conference (2014, July)

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See detailWhich are the determinants of homeownership ? A logit analysis for the case of Belgium
Xhignesse, Guillaume ULg; Bianchet, Bruno ULg; Cools, Mario ULg et al

Conference (2014, July)

In market-oriented economies, high rates of homeowners are traditionally associated with positive economic effects and externalities. For this reason, public authorities have encouraged homeownership for ... [more ▼]

In market-oriented economies, high rates of homeowners are traditionally associated with positive economic effects and externalities. For this reason, public authorities have encouraged homeownership for the last decades through taxation or subsidies policies. In Belgium, owner-occupation has been promoted since the end of the nineteenth century and homeownership policy is considered as a key element of the Welfare state. Furthermore, the effectiveness of these policies is fundamentally based on a clear understanding of what determines homeownership. Therefore, the analysis of tenure determinants can provide inputs for the definition or the renewal of housing, taxation and subsidies policies. Considering this interest, this paper investigates the issue of housing tenure in Belgium. On the basis of previous related research, a model of tenure choice is estimated using a sample of 6,962 households. The observations follow clearly the general trends described for other countries. Higher income and age, couple status and the presence of dependent children have positive influences on homeownership. In addition, locations presenting a high density of population and a high centrality are associated with a lower probability of homeownership compared with other areas. The underlying significations of these variables are discussed in the paper. [less ▲]

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See detailMars dayglow review
Stiepen, Arnaud ULg

Conference (2014, July)

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See detailMars aurora review
Stiepen, Arnaud ULg

Conference (2014, July)

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See detailReassessing the Mainstream vs. Alternative/Independent Dichotomy or, the Double Awareness of the Vertigo Imprint
Dony, Christophe ULg

in Dony, Christophe; Habrand, Tanguy; Meesters, Gert (Eds.) La bande dessinée en dissidence / Comics in Dissent (2014)

This article examines how the traditional mainstream vs. alternative/independent dichotomy usually employed to characterize the cultural production of comics in the US may have become outdated, and ... [more ▼]

This article examines how the traditional mainstream vs. alternative/independent dichotomy usually employed to characterize the cultural production of comics in the US may have become outdated, and perhaps even obsolete, when considering and analyzing the editorial policies and ideological agenda of Vertigo, DC’s adult-oriented imprint. More specifically, this essay sheds light on how Vertigo engages in a critical, ironic, and sometimes ambiguous discourse with both the history of the medium and staple practices and traditions from the mainstream and alternative wings of the American comics production. In so doing, I maintain that Vertigo is characterized by a hybrid identity and has developed a “double awareness” that allows it to appeal to both mainstream and alternative audiences. Vertigo’s hybridity, however, is not devoid of cultural, political, and even sociological implications that upset the categories of reception and production structuring the field of American comics. These implications underlying both the hybrid character of the label and its concomitant politics of demarcation in regards to the mainstream/alternatve dialectic will first be explored through the label’s obsession with processes of rewriting and recuperation, and second, through a close-reading of some of Vertigo promotional books’ covers. [less ▲]

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See detailCollapsing and reswelling kinetics of thermoresponsive polymers on surfaces: a matter of confinement and constraints
Willet, Nicolas ULg; Gabriel, Sabine ULg; Jérôme, Christine ULg et al

in Soft Matter (2014), 10

We report on the collapsing and reswelling ability of grafted poly(methyl vinyl ether) chains of different molecular architectures. In order to study the influence of constraints and confinement of the ... [more ▼]

We report on the collapsing and reswelling ability of grafted poly(methyl vinyl ether) chains of different molecular architectures. In order to study the influence of constraints and confinement of the chains, the polymer was grafted onto AFM tips, as a model of a curved nano-sized surface, and onto macroscopic silicon substrates for comparison purposes. AFM-based force spectroscopy experiments were performed to characterise at the nanoscale the temperature-dependent collapsing process and the reversibility to the swollen state on both substrates. The reversible character of the thermoresponsive transition and its kinetics were shown to greatly depend on the polymer architecture and the constraints encountered by the chains. [less ▲]

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See detailHighly dispersed iron xerogel catalysts for p-nitrophenol degradation by photo-Fenton effects
Mahy, Julien ULg; Tasseroul, Ludivine ULg; Zubiaur, Anthony ULg et al

Poster (2014, July)

Since the beginning of the industrial era, the various human activities have increased steadily, leading to a rapid technological development and a high population growth. Thus, the expansion of the ... [more ▼]

Since the beginning of the industrial era, the various human activities have increased steadily, leading to a rapid technological development and a high population growth. Thus, the expansion of the industry has heavily polluted the atmosphere, soil and water with negative consequences for humans and environment [1]. To decrease this pollution, it exists various treatment methods: chemical, physical and biological [2,3]. Among all these methods, a recent way of treatment is the degradation of pollutants in soils or waters by Fenton and photo-Fenton reactions [3] which use H2O2, iron-based compounds and UV light. In this way, several Fe2O3/SiO2 xerogel catalysts were synthesized by cogelation method by hydrolysis and condensation of tetraethoxysilane (TEOS) and 3-(2-aminoethylamino)propyltrimethoxysilane (EDAS) which is able to form a chelate with iron ions [4]. Five samples were synthesized: four samples with different percentage of iron (0.5, 1, 1.5 and 2.5 theoretical wt% confirmed by ICP-AES measurements), and a sample of pure silica. TEM pictures, nitrogen adsorption-desorption and mercury porosimetry measurements have established that EDAS plays a role of nucleating agent of silica particles [5,6] and allows to anchor iron particles inside silica network [4]. Indeed, it results iron nanoparticles of diameter 1-1.5 nm encapsulated in silica particles with sizes of about 10-30 nm in diameter. The species of iron was determined by Mössbauer spectroscopy and only Fe3+ ions were observed in xerogel catalysts. Then, the Fenton and photo-Fenton effect of these catalysts were evaluated on the degradation of p-nitrophenol (PNP) in aqueous medium in different conditions. Results show that Fe2O3/SiO2 xerogels present a photo-Fenton effect with H2O2, reaching with a sample 99 % of degradation after 24 h. [1] M. A. Khan, A. M. Ghouri, Environmental pollution: its effects on life and its remedies, Journal of Arts, Science & Commerce (Vol. 2), 2011, pg 276-285. [2] M. S. Kuyukina , I. B. Ivshina, Biology of rhodococcus: chapter 9, Springer, 2010, pg 232-256. [3] J. J. Pignatello, E. Oliveros, A. MacKay, Advanced Oxidation Processes for Organic Contaminant Destruction Based on the Fenton Reaction and Related Chemistry, Critical Reviews in Environmental Science and Technology (Vol. 36), 2006, pg 1-84. [4] B. Heinrichs, L. Rebbouh, J.W. Geus, S. Lambert, H.C.L. Abbenhuis, F. Grandjean, G.J. Long, J.-P. Pirard, R.A. van Santen, Iron (III) species dispersed in porous silica through sol-gel chemistry, Journal of Non-Crystalline Solids (Vol. 354), 2008, pg 665-672. [5] S. Lambert, C. Alié, J.-P. Pirard, B. Heinrichs, Study of textural properties and nucleation phenomenon in Pd/SiO2 , Ag/SiO2 and Cu/SiO2 cogelled xerogel catalysts, Journal of Non-Crystalline Solids (Vol. 342), 2004, pg 70-81. [6] B. Heinrichs, S. Lambert , N. Job , J.-P. Pirard, in "Catalyst Preparation: Science and Engineering, J. R. Regalbuto (Ed.)", CRC Press, Taylor & Francis Group, Boca Raton, 2007, p. 163-208. [less ▲]

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See detailFatigue index reproducibility in isokinetic testing
Paulus, Julien ULg; Croisier, Jean-Louis ULg; Bosquet, Laurent et al

in De Haan, Arnold; De Ruiter, Jo; Tsolakidis, Elias (Eds.) Book of abstracts (2014, July)

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See detailMémoire à ciel ouvert. Une histoire de l’Espagne : 1931-1981
Molina Marmol, Maïté ULg; Muñoz, Ángeles

Book published by Territoires de la Mémoire (2014)

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See detailLa bande dessinée en dissidence : alternative, indépendance, auto-édition / Comics in Dissent: Alternative, Independence, Self-Publishing
Dony, Christophe ULg; Habrand, Tanguy ULg; Meesters, Gert

Book published by Presses Universitaires de Liège (2014)

This volume investigates the complex notion of dissent as it can be applied to contemporary comics in confronting field and market logic, legitimation strategies, and social, cultural, political and ... [more ▼]

This volume investigates the complex notion of dissent as it can be applied to contemporary comics in confronting field and market logic, legitimation strategies, and social, cultural, political and aesthetic discourses. How do artists and/or publishing structures distance themselves from a certain idea of the established order? In what ways do they challenge the existing systems and environments in which they operate? How can we characterize the many guises and sometimes conflicting objectives of a generally self-conscious (counter-)culture? And what kinds of symbolic exchanges can we observe between artistic and critical discourses? These are some of the questions that the here gathered essays explore in considering the practices and strategies of either so-called and/or selfproclaimed independent or alternative comics artists or publishers. [less ▲]

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See detailIntroduction (version française)
Dony, Christophe ULg; Habrand, Tanguy ULg; Meesters, Gert

in Dony, Christophe; Habrand, Tanguy; Meesters, Gert (Eds.) La bande dessinée en dissidence : alternative, indépendance, auto-édition / Comics in Dissent: Alternative, Independence, Self-Publishing (2014)

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See detailIntroduction (English version)
Dony, Christophe ULg; Habrand, Tanguy ULg; Meesters, Gert

in Dony, Christophe; Habrand, Tanguy; Meesters, Gert (Eds.) La bande dessinée en dissidence : alternative, indépendance, auto-édition / Comics in Dissent: Alternative, Independence, Self-Publishing (2014)

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See detailWhen children stop trusting what they have perceived
Geurten, Marie ULg; Willems, Sylvie; Meulemans, Thierry ULg

in Neuropsychological Rehabilitation Special Interest Group of the WFNR - Conference Programme (2014, July)

Background and aims: A common hypothesis to explain metamemory heuristics learning throughout childhood lies on the assumption that the knowledge underlying these metacognitive rules develop from people’s ... [more ▼]

Background and aims: A common hypothesis to explain metamemory heuristics learning throughout childhood lies on the assumption that the knowledge underlying these metacognitive rules develop from people’s prior day-to-day experiences. However, the specific processes that sustain this learning are still unclear. In this study, we examined the mechanisms implicated in this empirical development by manipulating the learned interpretation of the Easily Learned = Easily Remembered (ELER) heuristic through an implicit process involving the detection of environmental regularities. Method: A sample of sixty normally developing children aged 4-5, 6-7, and 8-9 years old was recruited for this study. Each child participated in three 60-minute sessions separated approximately by one-week interval and was trained to learn implicitly a reverse interpretation of the ELER heuristic. The influence of executive functions on children’s judgment of learning at posttest was also investigated. Results: In addition to an early development of the ELER heuristic, results revealed a reduction of this heuristic’s use after the implicit training in the two youngest groups. Furthermore, executive monitoring was demonstrated to account for the lack of change observed in older children after the training phases. Conclusions: In a developmental perspective, these findings present a coherent picture of children’s learning of metacognitive heuristics. Specifically, automatic and implicit learning was demonstrated to be followed by an effortful control of the heuristics’ use. [less ▲]

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