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See detailSpectral Analysis and Abundances of the Post-HB Star HD 76431
Khalack, V.; Yameogo, B.; LeBlanc, F. et al

in Monthly Notices of the Royal Astronomical Society (in press)

HD76431 is a slow rotating post-HB star that shows an underabundance of helium by 0.5 dex relative to the solar value. These observational facts suggest that atomic diffusion could be active in its ... [more ▼]

HD76431 is a slow rotating post-HB star that shows an underabundance of helium by 0.5 dex relative to the solar value. These observational facts suggest that atomic diffusion could be active in its atmosphere. We have used the MMT and Bok spectra to estimate the atmospheric parameters of the target star using the model atmospheres and synthetic spectra calculated with TLUSTY and SYNSPEC. The derived values of the effective temperature, surface gravity, helium abundance are consistent with those obtained by Ramspeck et al. (2001b). It appears that NLTE effect are not important for HD76431. We have used Stokes I spectra from ESPaDOnS at CFHT to perform an abundance analysis and a search for observational evidence of vertical stratification of the abundance of certain elements. The results of our abundance analysis are in good agreement with previously published data with respect to average abundances. Our numerical simulations show that carbon and nitrogen reveal signatures of vertical abundance stratification in the atmosphere of HD76431. It appears that the carbon abundance increases toward the deeper atmospheric layers. Nitrogen also shows a similar behaviour, but in deeper atmospheric layers we obtain a significant dispersion for the estimates of its abundance. To our knowledge, this is the first demonstration of vertical abundance stratification of metals in a post-HB star and up to now it is the hottest star to show such stratification features. We also report the detection of two SiIII and one TiIII emission lines in the spectra of HD76431 that were not detected in previous studies. [less ▲]

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See detailStakeholder incentives and aid effectiveness: A case study in the health district of Kayes in Mali
Devahive, Eva; Paul, Elisabeth ULg; Samaké, Salif et al

in Journal of Development Studies (in press)

This case study analyses how far donors implement aid effectiveness principles at health district level in Mali, and why. It shows that not all aid effectiveness principles are implemented at a similar ... [more ▼]

This case study analyses how far donors implement aid effectiveness principles at health district level in Mali, and why. It shows that not all aid effectiveness principles are implemented at a similar degree. Most projects have limited impact on health services, but many programmes supported by donors offer positive opportunities for health system strengthening. The representations of different categories of stakeholders diverge – notably, regarding the role of different actors in service provision. A number of consistent strategic logics influence actors’ behaviour. We show that while many donors have committed at global level to respect aid effectiveness principles, implementation lags behind. [less ▲]

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See detailgammaMAXT: a fast multiple-testing correction algorithm
Van Lishout, François ULg; Gadaleta, Francesco ULg; Moore, Jason H. et al

in ERCIM 2014 Abstract Book (in press)

The purpose of the maxT algorithm (1993) is to control the family-wise error rate (FWER) when assessing significance of multiple tests jointly. However, the requirements in terms of computing time and ... [more ▼]

The purpose of the maxT algorithm (1993) is to control the family-wise error rate (FWER) when assessing significance of multiple tests jointly. However, the requirements in terms of computing time and memory of this procedure are proportional to the number of investigated hypothesis. The memory issue has been solved by Van Lishout’s implementation of maxT (2013), which makes the memory usage independent from the size of the dataset. This algorithm is implemented in MBMDR-3.0.3, a software that is able to identify genetic interactions, for a variety of SNP-SNP based epistasis model,s in an effective way. However, that implementation turned out to be less suitable for genome-wide interaction analysis studies, due to the prohibitive computational burden. Here, we present gammaMAXT, a novel algorithm which is part of MBMDR-4.2.2. We show that, in the abscence of interaction effects, test-statistics produced by the MB-MDR methodology follow a mixture distribution with a point mass at zero and a shifted gamma distribution for the top 10% of the strictly positive values. We show that the gammaMAXT algorithm has a power comparable to maxT and maintains FWER, but requires less computational resources and time. MBMDR-4.2.2 can be downloaded at http://www.statgen.ulg.ac.be. [less ▲]

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See detailPerformance-Based Aid: Why it will probably not meet promises
Paul, Elisabeth ULg

in Development Policy Review (in press)

Performance-based aid (PBA) is increasingly advocated as a way to improve development aid effectiveness through resolving incentive issues inherent in aid relationships. Some donors use PBA together with ... [more ▼]

Performance-based aid (PBA) is increasingly advocated as a way to improve development aid effectiveness through resolving incentive issues inherent in aid relationships. Some donors use PBA together with performance-based financing arrangements within partner countries. Expectations from PBA are high – yet, while its rationale may look appealing, it is grounded on a restrictive model and flawed when taking account of real-world context. A number of problems associated to PBA have already been advanced as jeopardising its success. More fundamentally, one may question the mere appropriateness of PBA to provide incentives all along the chain from recipient governments to those who are supposed to produce results. Thus believing that PBA can have a mechanistic trickle-down incentive effect seems an illusion. [less ▲]

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See detailLa conception d’un programme de formation pédagogique : un premier pas vers le développement professionnel des enseignants du supérieur
Poumay, Marianne ULg

in Daele, Amaury; Sylvestre, Emmanuel (Eds.) Le conseil pédagogique dans l’enseignement supérieur - Cadres de référence, outils de travail et de développement (in press)

Elaborer un programme de formation pour les enseignants est souvent le premier réflexe d’une cellule de conseillers pédagogiques nouvellement créée au sein d’une institution d’enseignement supérieur. Un ... [more ▼]

Elaborer un programme de formation pour les enseignants est souvent le premier réflexe d’une cellule de conseillers pédagogiques nouvellement créée au sein d’une institution d’enseignement supérieur. Un tel programme permet en effet une première sensibilisation aux questions d’apprentissage, une première étape dans ce qui pourrait devenir une réelle politique de développment professionnel pour les enseignants. Mais quelles sont les limites d’une telle approche ? Quelles sont ses conditions d’efficacité ? Au vu de quelques expériences européennes et notamment celle de l’université de Liège (Belgique), ce chapitre tente d’éclairer les défis majeurs qui attendent les conseillers pédagogiques au détour de leur conception d’un tel programme. [less ▲]

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See detailThe Instability Strip of ZZ Ceti White Dwarfs
Van Grootel, Valérie ULg; Fontaine, G.; Brassard, P. et al

in Astronomical Society of the Pacific Conference Series (in press)

The determination of the location of the theoretical ZZ Ceti instability strip in the log g − Teff diagram has remained a challenge over the years, due to the lack of a suitable treatment for convection ... [more ▼]

The determination of the location of the theoretical ZZ Ceti instability strip in the log g − Teff diagram has remained a challenge over the years, due to the lack of a suitable treatment for convection in these stars. We report here a detailed stability survey over the whole ZZ Ceti regime, including the low and extremely low masses. We computed to this aim 29 evolutionary sequences of DA models with various masses, chemical layering, and core compositions. These models are characterized by the so- called ML2/α=1.0 convective efficiency and take into account the important feedback effect of convection on the atmospheric structure. We computed pulsation spectra for these models with the Liège nonadiabatic pulsation code MAD, which is the only one to conveniently incorporate a full time-dependent convection treatment and, thus, provides the best available description of the blue edge of the instability strip. On the other hand, given the failure of all nonadiabatic codes to account properly for the red edge of the strip, including MAD, we tested the idea that the red edge is due to energy leakage through the atmosphere. Using this approach, we found that our theoretical ZZ Ceti instability strip accounts remarkably well for the boundaries of the empirical strip. [less ▲]

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See detailA First Look at the Nonadiabatic Properties of Pulsating Accreting White Dwarfs of the GW Lib Type
Van Grootel, Valérie ULg; Fontaine, G.; Brassard, P. et al

in Astronomical Society of the Pacific Conference Series (in press)

We present results of a detailed stability survey of the pulsation properties of accreting white dwarfs of the GW Lib type. This is based on several state-of-the- art white dwarf evolutionary sequences ... [more ▼]

We present results of a detailed stability survey of the pulsation properties of accreting white dwarfs of the GW Lib type. This is based on several state-of-the- art white dwarf evolutionary sequences with varying envelope compositions, from pure hydrogen to pure helium. Using the same tools as in Van Grootel et al. (2013), where we have presented the first consistent view of the ZZ Ceti instability strip, we have mapped the GW Lib instability strip over the effective temperature-surface gravity plane, and as a function of envelope composition. We find that the location of the GW Lib instability domain is a strong and continuous function of the assumed envelope composition. We can accomodate all of the known GW Lib pulsators in various strips according to their atmospheric compositions. [less ▲]

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See detailA global analysis of Spitzer and new HARPS data confirms the loneliness and metal-richness of GJ 436 b
Lanotte, Audrey ULg; Gillon, Michaël ULg; Demory, B.-O. et al

in Astronomy and Astrophysics (in press)

Context. GJ 436b is one of the few transiting warm Neptunes for which a detailed characterisation of the atmosphere is possible, whereas its non-negligible orbital eccentricity calls for further ... [more ▼]

Context. GJ 436b is one of the few transiting warm Neptunes for which a detailed characterisation of the atmosphere is possible, whereas its non-negligible orbital eccentricity calls for further investigation. Independent analyses of several individual datasets obtained with Spitzer have led to contradicting results attributed to the different techniques used to treat the instrumental effects. Aims. We aim at investigating these previous controversial results and developing our knowledge of the system based on the full Spitzer photometry dataset combined with new Doppler measurements obtained with the HARPS spectrograph. We also want to search for additional planets. Methods. We optimise aperture photometry techniques and the photometric deconvolution algorithm DECPHOT to improve the data reduction of the Spitzer photometry spanning wavelengths from 3-24 {\mu}m. Adding the high precision HARPS radial velocity data, we undertake a Bayesian global analysis of the system considering both instrumental and stellar effects on the flux variation. Results. We present a refined radius estimate of RP=4.10 +/- 0.16 R_Earth, mass MP=25.4 +/- 2.1 M_Earth and eccentricity e= 0.162 +/- 0.004 for GJ 436b. Our measured transit depths remain constant in time and wavelength, in disagreement with the results of previous studies. In addition, we find that the post-occultation flare-like structure at 3.6 {\mu}m that led to divergent results on the occultation depth measurement is spurious. We obtain occultation depths at 3.6, 5.8, and 8.0 {\mu}m that are shallower than in previous works, in particular at 3.6 {\mu}m. However, these depths still appear consistent with a metal-rich atmosphere depleted in methane and enhanced in CO/CO2, although perhaps less than previously thought. We find no evidence for a potential planetary companion, stellar activity, nor for a stellar spin-orbit misalignment. [ABRIDGED] [less ▲]

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See detailA review of inversion techniques related to the use of relationship matrices in animal breeding
Faux, Pierre ULg; Gengler, Nicolas ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (in press)

In animal breeding, prediction of genetic effects is usually obtained through the use of mixed models. For any of these genetic effects, mixed models require the inversion of the covariance matrix ... [more ▼]

In animal breeding, prediction of genetic effects is usually obtained through the use of mixed models. For any of these genetic effects, mixed models require the inversion of the covariance matrix associated to that effect, which is equal to the associated relationship matrix times the associated component of the genetic variance. Given the size of many genetic evaluation systems, computing the inverses of these relationship matrices is not trivial. In this review, we aim to cover computational techniques that ease inversion of relationship matrices used in animal breeding for prediction of the following different types of genetic effects: additive effect, gametic effect, effect due to presence of marked quantitative trait loci, dominance effect and different epistasis effects. Construction rules and inversion algorithms are detailed for each relationship matrix. In the final discussion, we draw up a common theoretical frame to most of the reviewed techniques. Two computational constraints come out of this theoretical frame: setting up the matrix of dependencies between levels of the effect and setting up some parts (diagonal or block-diagonal elements) of the relationship matrix to be inverted. [less ▲]

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See detailThe construction of workers’ rights consciousness through legal intermediations: the case of employment discrimination in Belgium
Lejeune, Aude ULg; Orianne, Jean-François ULg

in International Journal of Discrimination and the Law (in press)

Through their different encounters with union, court, and government equality agency lawyers, workers report diverse understandings of their personal experience of injustice in the workplace. This paper ... [more ▼]

Through their different encounters with union, court, and government equality agency lawyers, workers report diverse understandings of their personal experience of injustice in the workplace. This paper examines workers’ experiences of discrimination and the role legal professionals play in litigating these issues in Belgium. Bringing together legal and rights consciousness studies and the sociology of intermediation and tracking different stages in the construction of discrimination cases, from the moment when a future litigant describes an event as an injustice to the moment when the judge recognises a discriminatory behaviour (or conversely, dismisses a case), we suggest several possible empirical explanations of the way in which interactions with legal intermediaries affect workers’ rights consciousness. Because we refer to socio-legal studies from common law countries, this paper also calls into question how best to import these studies to assist in analysing legal mobilisations and legal consciousness in continental Europe. [less ▲]

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See detailThe strength of multi-row models
Louveaux, Quentin ULg; Poirrier, Laurent; Salvagnin, Domenico

in Mathematical Programming Computation (in press)

We develop a method for computing facet-defining valid inequalities for any mixed-integer set PJ. Our practical implementation does not return only facet- defining inequalities, but it is able to find a ... [more ▼]

We develop a method for computing facet-defining valid inequalities for any mixed-integer set PJ. Our practical implementation does not return only facet- defining inequalities, but it is able to find a separating cut whenever one exists. The separator is not comparable in speed with the specific cutting-plane generators used in branch-and-cut solvers, but it is general-purpose. We can thus use it to compute cuts derived from any reasonably small relaxation PJ of a general mixed- integer problem, even when there exists no specific implementation for computing cuts with PJ. Exploiting this, we evaluate, from a computational perspective, the usefulness of cuts derived from several types of multi-row relaxations. In particular, we present results with four different strengthenings of the two-row intersection cut model, and multi-row models with up to fifteen rows. We conclude that only fully-strengthened two-row cuts seem to offer a significant advantage over two-row intersection cuts. Our results also indicate that the improvement obtained by going from models with very few rows to models with up to fifteen rows may not be worth the increased computing cost. [less ▲]

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See detailMollino, Carlo
Prina, Daniela ULg

in Atkinson, Harriet; Kettley, Sarah; Edwards, Clive (Eds.) et al Encyclopedia of Design (in press)

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See detailIdentifying Semitic loanwords in Late Egyptian
Winand, Jean ULg

in Dils, Peter; Grossman, Eitan; Richter, Sebastian (Eds.) et al Language Contact and Bilingualism in antiquity: What Linguistic Borrowing into Coptic can tell us about it (in press)

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See detailSapper, Richard
Prina, Daniela ULg

in Atkinson, Harriet; Kettley, Sarah; Edwards, Clive (Eds.) et al Encyclopedia of Design (in press)

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See detailThe impact of transport policies on railroad intermodal freight competitiveness – The case of Belgium
Santos, Bruno F.; Limbourg, Sabine ULg; Carreira, Joana Silva

in Transportation Research. Part D : Transport and Environment (in press)

This paper discusses the impact of three freight transport policies aiming to promote railroad intermodal transport in Europe, and examines the case of Belgium as a testing ground. These policies consist ... [more ▼]

This paper discusses the impact of three freight transport policies aiming to promote railroad intermodal transport in Europe, and examines the case of Belgium as a testing ground. These policies consist in subsidizing intermodal transport operations (such as in Belgium, to stimulate rail transport), internalizing external costs (as recommended by the European Union in order to foster cleaner modes), and adopting a system perspective when optimizing the location of inland intermodal terminals. The study proposes an innovative mixed integer intermodal freight location-allocation model based on hub-location theory and deals with non-linear transport costs in order to replicate economies of distance. Our analysis suggests that subsidizing has a significant impact on the volumes transported by intermodal transport, and, to a lesser extent, that optimizing terminal location increases the competitiveness of intermodal transport. On the other hand, according to our assumptions, internalizing external costs can negatively impact the promotion of intermodality. This finding indicates that innovative last-mile transports are needed in order to reduce the external impacts of drayage operations. [less ▲]

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See detailDevelopment by the sol–gel process of highly dispersed Ni–Cu/SiO2 xerogel catalysts for selective 1,2-dichloroethane hydrodechlorination into ethylene
Pirard, Sophie ULg; Mahy, Julien ULg; Pirard, Jean-Paul ULg et al

in Microporous and Mesoporous Materials (in press)

Ni–Cu/SiO2 xerogel catalysts have been synthesized by cogelation of industrial tetraethoxysilane (Dynasil) and chelates of Ni and Cu with industrial 3-(2-aminoethylamino)propyltrimethoxysilane (Dynasylan ... [more ▼]

Ni–Cu/SiO2 xerogel catalysts have been synthesized by cogelation of industrial tetraethoxysilane (Dynasil) and chelates of Ni and Cu with industrial 3-(2-aminoethylamino)propyltrimethoxysilane (Dynasylan DAMO) in industrial ethanol denatured with diethyl phthalate. Despite the use of industrial grade reagents, highly dispersed bimetallic Ni–Cu/SiO2 xerogel catalysts were obtained. These samples are composed of completely accessible Ni–Cu alloy crystallites with sizes of 1.6–3.4 nm located inside silica particles exhibiting a monodisperse microporous distribution. It appears that the bimetallic complex acts as a nucleation agent in the formation of silica particles. The combination of results obtained from the calculation of the metal ratio in catalysts, H2 chemisorption and transmission electron microscopy allowed calculating the surface composition of the nickel–copper particles in Ni–Cu/SiO2 cogelled xerogel catalysts. Values obtained indicate a very pronounced surface enrichment with copper. While 1,2-dichloroethane hydrodechlorination over pure nickel mainly produces ethane, increasing copper content in bimetallic catalysts results in an increase in ethylene selectivity. The specific consumption rate of 1,2-dichloroethane decreases when copper loading increases. The turnover frequency, that is, the number of catalytic cycle per active site (nickel atom and its surrounding copper atoms) and per second, seems to be independent of surface composition of alloy particles. [less ▲]

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See detailDes ethnonymes aux glottonymes : enjeux de la nomination des pratiques linguistiques en Louisiane francophone
Urbain, Emilie ULg

in Jean-Michel Eloy (Ed.) Nommer des langues romanes (in press)

Detailed reference viewed: 12 (4 ULg)