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See detailThree sub-Jupiter-mass planets: WASP-69b & WASP-84b transit active K dwarfs and WASP-70Ab transits the evolved primary of a G4+K3 binary
Anderson, D. R.; Collier Cameron, A.; Delrez, Laetitia ULg et al

in Monthly Notices of the Royal Astronomical Society (2014), 445(2),

We report the discovery of the transiting exoplanets WASP-69b, WASP-70Ab and WASP-84b, each of which orbits a bright star (V ˜ 10). WASP-69b is a bloated Saturn-mass planet (0.26 MJup, 1.06 RJup) in a 3 ... [more ▼]

We report the discovery of the transiting exoplanets WASP-69b, WASP-70Ab and WASP-84b, each of which orbits a bright star (V ˜ 10). WASP-69b is a bloated Saturn-mass planet (0.26 MJup, 1.06 RJup) in a 3.868-d period around an active, ˜1-Gyr, mid-K dwarf. ROSAT detected X-rays 60±27 arcsec from WASP-69. If the star is the source then the planet could be undergoing mass-loss at a rate of ˜1012 g s-1. This is one to two orders of magnitude higher than the evaporation rate estimated for HD 209458b and HD 189733b, both of which have exhibited anomalously large Lyman alpha absorption during transit. WASP-70Ab is a sub-Jupiter-mass planet (0.59 MJup, 1.16 RJup) in a 3.713-d orbit around the primary of a spatially resolved, 9-10-Gyr, G4+K3 binary, with a separation of 3.3 arcsec (>=800 au). WASP-84b is a sub-Jupiter-mass planet (0.69 MJup, 0.94 RJup) in an 8.523-d orbit around an active, ˜1-Gyr, early-K dwarf. Of the transiting planets discovered from the ground to date, WASP-84b has the third-longest period. For the active stars WASP-69 and WASP-84, we pre-whitened the radial velocities using a low-order harmonic series. We found that this reduced the residual scatter more than did the oft-used method of pre-whitening with a fit between residual radial velocity and bisector span. The system parameters were essentially unaffected by pre-whitening. [less ▲]

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See detailPlasma riche en plaquettes et tendinopathies
KAUX, Jean-François ULg; Crielaard, Jean-Michel ULg

in Ortho-Rhumato (2014), 12(6), 35-39

Certaines tendinopathies présentent une évolution désespérément chronique malgré l’instauration d’un traitement conservateur bien conduit. Diverses études soulignent les propriétés réparatrices des ... [more ▼]

Certaines tendinopathies présentent une évolution désespérément chronique malgré l’instauration d’un traitement conservateur bien conduit. Diverses études soulignent les propriétés réparatrices des plaquettes qui pourraient accélérer la cicatrisation de différents tissus. Le plasma riche en plaquettes (platelet-rich plasma ou PRP) représenterait une thérapeutique d’avenir. Les plaquettes libéraient, lors de leur dégranulation, divers facteurs de croissance. Ceux-ci favoriseraient la cicatrisation tendineuse. Actuellement, les effets du PRP restent toujours discutés voire controversés : les résultats cliniques sont parfois contradictoires même si son efficacité in vitro et sur animal apparait plus franche. Cette variabilité pourrait s’expliquer par l’absence de consensus relatif au mode de préparation du PRP, à la concentration plaquettaire, à la présence ou non de leucocytes, à la technique d’infiltration et au protocole post-infiltration. [less ▲]

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See detailPolysaccharide-coated PCL nanofibers for wound dressing applications
Croisier, Florence ULg; Atanasova, Ganka; Poumay, Yves et al

in Advanced Healthcare Materials (2014), 3(12), 2032-2039

Polysaccharide-based nanofibers with amultilayered structure are prepared by combining electrospinning (ESP) and layer-by-layer (LBL) deposition techniques. Charged nanofibers are firstly prepared by ... [more ▼]

Polysaccharide-based nanofibers with amultilayered structure are prepared by combining electrospinning (ESP) and layer-by-layer (LBL) deposition techniques. Charged nanofibers are firstly prepared by electrospinning poly(ε-caprolactone) (PCL) with a block-copolymer bearing carboxylic acid functions. After deprotonation of the acid groups, the layer-by-layer deposition of polyelectrolyte polysaccharides, notably chitosan and hyaluronic acid, is used to coat the electrospun fibers. A multilayered structure is achieved by alternating the deposition of the positively charged chitosan with the deposition of a negatively charged polyelectrolyte. The construction of this multi-layered structure is followed by Zeta potential measurements, and confirmed by observation of hollow nanofibers resulting from the dissolution of the PCL core in a selective solvent. These novel polysaccharide-coated PCL fiber mats remarkably combine the mechanical resistance typical of the core material (PCL) – particularly in the hydrated state –, with the surface properties of chitosan. The control of the nanofiber structure offered by the electrospinning technology, makes the developed process very promising to precisely design biomaterials for tissue engineering. Preliminary cell culture tests corroborate the potential use of such system in wound healing applications. [less ▲]

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See detailUsing approximate dynamic programming for estimating the revenues of a hydrogen-based high-capacity storage device
François-Lavet, Vincent ULg; Fonteneau, Raphaël ULg; Ernst, Damien ULg

in IEEE Symposium Series on Computational Intelligence (2014)

This paper proposes a methodology to estimate the maximum revenue that can be generated by a company that operates a high-capacity storage device to buy or sell electricity on the day-ahead electricity ... [more ▼]

This paper proposes a methodology to estimate the maximum revenue that can be generated by a company that operates a high-capacity storage device to buy or sell electricity on the day-ahead electricity market. The methodology exploits the Dynamic Programming (DP) principle and is specified for hydrogen-based storage devices that use electrolysis to produce hydrogen and fuel cells to generate electricity from hydrogen. Experimental results are generated using historical data of energy prices on the Belgian market. They show how the storage capacity and other parameters of the storage device influence the optimal revenue. The main conclusion drawn from the experiments is that it may be advisable to invest in large storage tanks to exploit the inter-seasonal price fluctuations of electricity. [less ▲]

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See detailExperimental validation of a thermal model of a LOx flooded ball bearing
Servais, Christophe ULg; Bozet, Jean-Luc ULg; Kreit, Patrick ULg et al

in Tribology International (2014), 80

Ball bearings of turbopumps of rocket engines work in very singular conditions; they are flooded into liquid oxygen or liquid hydrogen. Therefore, the use of any conventional lubricants (oil or grease) is ... [more ▼]

Ball bearings of turbopumps of rocket engines work in very singular conditions; they are flooded into liquid oxygen or liquid hydrogen. Therefore, the use of any conventional lubricants (oil or grease) is prescribed. Although cryogenic fluids can cool this kind of ball bearing, they cannot separate the surfaces in contact. As a result, there is a significant increase in frictional power losses. This paper presents tests performed on a cryotechnic ball bearing flooded in liquid oxygen. The test results showed that beyond a critical loading of the bearing, a sudden increase in temperature occurred. A thermal model is also put forward, in order to understand and anticipate especially the thermal instability described above. [less ▲]

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See detailLe roman pour la jeunesse: un roman éducatif qui ne dit jamais son nom
Delbrassine, Daniel ULg

in Van Beveren, Julien (Ed.) Littérature, langue et didactique. Hommages à Jean-Louis Dumortier (2014)

Démonstration du caractère éducatif du roman pour la jeunesse actuel: à travers des procédés implicites typiques du roman moderne, les auteurs continuent de dispenser un message aux lecteurs.

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See detailSustainable Chemistry
Gillet, Sébastien ULg; Jacquet, Nicolas ULg; Richel, Aurore ULg

Learning material (2014)

1) Petrochemical and concept of biorefineries. 2) Biomass and biorefineries, 1st generation 3) Biomass and biorefineries, second generation 4) Green Chemistry and Green Engineering

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See detailExplaining the CMS Higgs lepton-flavor violating
Aristizabal Sierra, Diego ULg; Vicente, Avelino ULg

in Physical Review. D : Particles and Fields (2014), 90(11), 115004

Direct searches for lepton flavor violating Higgs boson decays in the τ μ channel have been recently reported by the CMS collaboration. The results display a slight excess of signal events with a ... [more ▼]

Direct searches for lepton flavor violating Higgs boson decays in the τ μ channel have been recently reported by the CMS collaboration. The results display a slight excess of signal events with a significance of 2.5σ, which translates into a branching ratio of about 1%. By interpreting these findings as a hint for beyond the standard model physics, we show that the Type-III 2HDM is capable of reproducing such signal while at the same time satisfying vacuum stability, perturbativity, electroweak precision data, measured Higgs standard decay modes and low-energy lepton flavor violating constraints. We have found that the allowed signal strength ranges for the bb, WW* and ZZ* standard channels shrink as soon as BR(h→τμ)∼ 1% is enforced. Thus, we point out that if the excess persists, improved measurements of these channels may be used to test our Type-III 2HDM scenario. [less ▲]

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See detailImpact of gender difference in hospital outcomes following percutaneous coronary intervention. Results of the Belgian Working Group on Interventional Cardiology (BWGIC) registry
LEMPEREUR, Mathieu ULg; Magne, Julien; Cornelis, Kristoff et al

in EuroIntervention : Journal of EuroPCR in Collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology (2014)

Aims: To determine whether there are gender-based differences in in-hospital outcomes among patients undergoing percutaneous coronary intervention (PCI). Methods and results: We studied a large cohort ... [more ▼]

Aims: To determine whether there are gender-based differences in in-hospital outcomes among patients undergoing percutaneous coronary intervention (PCI). Methods and results: We studied a large cohort using clinical data from a registry of 130,985 PCI procedures in Belgium, from January 2006 to February 2011. Compared to males, females were significantly older (70.3 vs. 64.8 years), and were more frequently diabetic or hypertensive. Men smoked more and more frequently had previous myocardial infarction (MI), previous PCI or previous coronary artery bypass graft (CABG) surgery. Coronary artery disease (CAD) was less severe in women, and PCI to the left anterior descending artery was more common in female patients. Unadjusted in-hospital mortality rates were higher in females versus males (2.5% for women and 1.6% for men, p<0.0001). After multivariable analysis, female gender remained an independent predictor of mortality (odds ratio 1.35, 95% CI: 1.22-1.49, p<0.0001). Conclusions: Gender-based differences in hospital mortality rates after PCI were observed in this large registry. Female sex remained an independent predictor of mortality after multivariable adjustment. [less ▲]

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See detailInput of supercritical carbon dioxide to polymer synthesis: an overview
Boyère, Cédric; Jérôme, Christine ULg; Debuigne, Antoine ULg

in European Polymer Journal (2014), 61

The ongoing search for environmentally friendlier alternative to the organic solvents used in chemical processes has led to the development of technologies based on supercritical carbon dioxide (scCO2 ... [more ▼]

The ongoing search for environmentally friendlier alternative to the organic solvents used in chemical processes has led to the development of technologies based on supercritical carbon dioxide (scCO2), which is non-flammable, non-toxic and relatively inert fluid. Polymer chemistry does not escape this trend and last achievements in the field of polymer synthesis in scCO2 are reviewed here. Without claiming to be exhaustive, we go through and discuss the benefits of the main polymerization processes in scCO2 including homogeneous, precipitation, dispersion, suspension and emulsion systems. A particular attention is drawn to water/carbon dioxide emulsion polymerization and to the suited surface active agents. This review also underlines that heterogeneous polymerization based on CO2 is more than a strategy for reducing the ecological footprint of the polymer production but it allows structuring the polymer materials into particles or highly interconnected macroporous networks. [less ▲]

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See detailFatigue et auto-évaluation chez des patients atteints de sclérose en plaques
DELRUE, Gaël ULg; Blavier, Adelaïde ULg; HENNEN, Julie et al

Poster (2014, December)

Different fatigue scales specific for multiple sclerosis patients correlate quite differently with other psychological measures which gives rise to a necessary reflexion about the tools used in clinical ... [more ▼]

Different fatigue scales specific for multiple sclerosis patients correlate quite differently with other psychological measures which gives rise to a necessary reflexion about the tools used in clinical practice and their meanings. [less ▲]

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See detailTransient small-scale structure in the main auroral emission at Jupiter
Palmaerts, Benjamin ULg; Radioti, Aikaterini ULg; Grodent, Denis ULg et al

in Journal of Geophysical Research. Space Physics (2014), 119

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See detailWhat can we learn from asteroseismology of β Cephei stars through forward approach modelling?
Salmon, Sébastien ULg; Montalban, J.; Miglio, A. et al

Poster (2014, December)

The beta Cephei pulsating stars present a unique opportunity to test and probe our knowledge on the interior of massive stars. The information we can obtain depends on the quality and number of ... [more ▼]

The beta Cephei pulsating stars present a unique opportunity to test and probe our knowledge on the interior of massive stars. The information we can obtain depends on the quality and number of observational constraints, both seismic and classical ones. The asteroseismology of beta Cephei stars proceeds by a forward approach, which often result in multiple solutions, without clear indication on the level of confidence. We seek a method to derive confidence intervals on stellar parameters obtained by forward approach and investigate how these latter behave depending the seismic data accessible to the observer. We realise forward modelling with help of a grid of pre-computed models and use Monte-Carlo simulations to build confidence intervals on the inferred stellar parameters. We apply and test this method in a series of hare and hound exercises on a subset of theoretical models simulating observed stars. Results show that a set of 5 frequencies (with knowledge of their associated angular degree) yields good seismic constraints. In particular, presence of mixed modes provides a strong diagnosis on the evolutionary state of the star. Significant errors on the determinination of the extent of the central mixed region appear when the theoretical models do not present the same chemical mixture as the observed star. [less ▲]

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See detailValidation d’un questionnaire d’ergonomie cognitive relatif au travail chez des patients atteints de sclerose en plaques
Blavier, Adelaïde ULg; DELRUE, Gaël ULg; HENNEN, Julie et al

Poster (2014, December)

We present datas validating the use of our QUIPSEP questionnaire among multiple sclerosis patients actually employed.

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See detailUn blog plutôt qu’un Word ? Retour d’expérience de l’insertion d’un cours en ligne dans un programme de formation d’enseignants du supérieur.
Jérôme, Françoise ULg; Verpoorten, Dominique ULg

in Education & Formation (2014), e-302

En 2012-2013, le CAPAES (Certificat d’Aptitude Pédagogique Approprié à l’Enseignement Supérieur) de l’Université de Liège a incorporé pour la première fois à son programme un cours entièrement en ligne ... [more ▼]

En 2012-2013, le CAPAES (Certificat d’Aptitude Pédagogique Approprié à l’Enseignement Supérieur) de l’Université de Liège a incorporé pour la première fois à son programme un cours entièrement en ligne. L’article en expose les motivations sous-jacentes, présente les outils utilisés et analyse la réception du dispositif par les étudiants. Les données récoltées font apparaitre : a) la familiarité antérieure restreinte des enseignants avec les deux outils exploités dans le cours (une plate-forme eLearning traditionnelle et un blog comme représentant du Web 2.0), b) la capacité, en dépit de cette familiarité limitée, de faire bon usage des deux outils en tant qu’apprenant, c) une satisfaction générale pour le cours en ligne mais faiblement liée à la découverte des deux outils et à la prise de conscience, en tant qu’enseignant, de leur potentiel pédagogique. (L'article fournit en annexe le questionnaire complet utilisé pour recueillir le feed-back des enseignants ayant terminé le cours en ligne). [less ▲]

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See detailOn Projection-Based Model Reduction of Biochemical Networks Part I: The Deterministic Case
Sootla, Aivar ULg; Anderson, James

in Proceedings of the 53rd IEEE Conference on Decision and Control (2014, December)

This paper addresses the problem of model reduction for dynamical system models that describe biochemical reaction networks. Inherent in such models are properties such as stability, positivity and ... [more ▼]

This paper addresses the problem of model reduction for dynamical system models that describe biochemical reaction networks. Inherent in such models are properties such as stability, positivity and network structure. Ideally these properties should be preserved by model reduction procedures, although traditional projection based approaches struggle to do this. We propose a projection based model reduction algorithm which uses generalised block diagonal Gramians to preserve structure and positivity. Two algorithms are presented, one provides more accurate reduced order models, the second provides easier to simulate reduced order models. [less ▲]

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See detailOn Projection-Based Model Reduction of Biochemical Networks Part II: The Stochastic Case
Sootla, Aivar ULg; Anderson, James

in Proceedings of the 53rd IEEE Conference on Decision and Control (2014, December)

In this paper, we consider the problem of model order reduction of stochastic biochemical networks. In particular, we reduce the order of (the number of equations in) the Linear Noise Approximation of the ... [more ▼]

In this paper, we consider the problem of model order reduction of stochastic biochemical networks. In particular, we reduce the order of (the number of equations in) the Linear Noise Approximation of the Chemical Master Equation, which is often used to describe biochemical networks. In contrast to other biochemical network reduction methods, the presented one is projection-based. Projection-based methods are powerful tools, but the cost of their use is the loss of physical interpretation of the nodes in the network. In order alleviate this drawback, we employ structured projectors, which means that some nodes in the network will keep their physical interpretation. For many models in engineering, finding structured projectors is not always feasible; however, in the context of biochemical networks it is much more likely as the networks are often (almost) monotonic. To summarise, the method can serve as a trade-off between approximation quality and physical interpretation, which is illustrated on numerical examples. [less ▲]

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See detailGeneral guidelines for planning and conducting round robins in EGOLF
Dumont, Fabien ULg; Steen-Hansen, Anne

Report (2014)

Conducting round robin exercises is one of EGOLF's key activities. A round robin exercise is a necessary tool to improve and maintain a good level of quality within EGOLF. A good plan of the round robin ... [more ▼]

Conducting round robin exercises is one of EGOLF's key activities. A round robin exercise is a necessary tool to improve and maintain a good level of quality within EGOLF. A good plan of the round robin exercise will make the work easier, and will help avoid problems and misunderstandings. The intention is to give general guidelines on how to organize round robins in a standardized way within EGOLF. The document is divided into the following parts - Preparing and planning the round robin - Testing - Data analysis and reporting These guidelines comply with the ISO 5725 prescriptions. [less ▲]

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