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See detailNutritive value of Adenodolichos rhomboideus leaves compared with Leucaena leucocephala and Stylosanthes guianensis forages in indigenous goats in Lubumbashi (DR Congo).
Tshibangu, Muamba Innocent; Nsahlai, Ignatus Verla; Kiatoko, Mangeye Honoré et al

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

Forage from three species (Adenodolichos rhomboideus, Leucaena leucocephala, Stylosanthes guianensis) were evaluated by determining chemical composition, voluntary intake and apparent in vivo ... [more ▼]

Forage from three species (Adenodolichos rhomboideus, Leucaena leucocephala, Stylosanthes guianensis) were evaluated by determining chemical composition, voluntary intake and apparent in vivo digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF). Six goats (17.1±0.7 kg) were used in 3 x 3 double latin square design to determine the digestibility and intake of the three forages. Forage from S. guianensis had lower (p<0.001) CP content than L. leucocephala forage and A. rhomboideus leaves. Fibres content (ADF and NDF) were lower (p<0.001) in L. leucocephala (35%) forage than A. rhomboideus (59.5%) leaves and S. guianensis forages (56.5%). L. leucocephala forage was superior in CP, Ash, EE concentrations, digestibility and voluntary intake of CP. A. rhomboideus leaves had lower (p<0.05) apparent digestibility and intake of DM. Digestible CP intake were similar between A. rhomboideus leaves and S. guianensis forages. Low digestibility and voluntary intake of A. rhomboideus leaves may be due to negative effect of anti-nutritional factor such as tannin. Digestible CP was similar for A. rhomboideus leaves and S. guianensis forage. [less ▲]

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See detailCapital symbolique
Durand, Pascal ULg

in COnTEXTES : Revue de Sociologie de la Littérature (in press)

Présentation et discussion du concept de « Capital symbolique » dans la sociologie de Pierre Bourdieu.

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See detailPrediction of SOx and NOx Emissions from a Medium Size Biomass Boiler Biomass and Bioenergy
Sartor, Kevin ULg; Restivo, Yannick ULg; Ngendakumana, Philippe ULg et al

in Biomass and Bioenergy (in press)

While small and medium size biomass combined heat and power (CHP) plants (i.e., up to 5 MW of electrical rated power) represent an attractive option to exploit locally available biomass resources at low ... [more ▼]

While small and medium size biomass combined heat and power (CHP) plants (i.e., up to 5 MW of electrical rated power) represent an attractive option to exploit locally available biomass resources at low cost, the corresponding investment per unit of rated power significantly rises when the installed power decreases. In these cases, secondary pollutant emissions control measures are most of the time not economically viable and primary emissions control must be used alone to avoid the formation of undesired compounds such as $NO_x$ and $SO_x$. Primary control measures require the careful optimization of fuel quality and combustion process. For plant operators, being able to accommodate biomass quality changes in order to minimize the fuel cost can be of great importance in order to guarantee the profitability of the plant. This contribution is dedicated to the development of a zero-dimensional (input-output) combustion simulation model able to predict the pollutants emissions resulting from complete and incomplete combustion with respect to varying combustion operation (ambient temperature, humidity, fumes recirculation,..). This tool is intended to be integrated in a global simulation model of the CHP plant and the attached district heating network installed on the University campus in Liège. Doing so, the plant operation can be optimized with respect to economic as well as environmental and energetic aspects (3E approach) thus ensuring the sustainability of the approach. [less ▲]

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See detailThiamine triphosphate: a ubiquitous molecule in search of a physiological role
Bettendorff, Lucien ULg; Wins, Pierre

in Metabolic Brain Disease (in press)

Thiamine triphosphate (ThTP) was discovered over 60 years ago and it was long thought to be a specifically neuroactive compound. Its presence in most cell types, from bacteria to mammals, would suggest a ... [more ▼]

Thiamine triphosphate (ThTP) was discovered over 60 years ago and it was long thought to be a specifically neuroactive compound. Its presence in most cell types, from bacteria to mammals, would suggest a more general role but this remains undefined. In contrast to thiamine diphosphate (ThDP), ThTP is not a coenzyme. In E. coli cells, ThTP is transiently produced in response to amino acid starvation, while in mammalian cells, it is constitutively produced at a low rate. Though it was long thought that ThTP was synthesized by a ThDP:ATP phosphotransferase, more recent studies indicate that it can be synthesized by two different enzymes: (1) adenylate kinase 1 in the cytosol and (2) FoF1-ATP synthase in brain mitochondria. Both mechanisms are conserved from bacteria to mammals. Thus ThTP synthesis does not seem to require a specific enzyme. In contrast, its hydrolysis is catalyzed, at least in mammalian tissues, by a very specific cytosolic thiamine triphosphatase (ThTPase), controlling the steady-state cellular concentration of ThTP. In some tissues where adenylate kinase activity is high and ThTPase is absent, ThTP accumulates, reaching ≥ 70% of total thiamine, with no obvious physiological consequences. In some animal tissues, ThTP was able to phosphorylate proteins, and activate a high-conductance anion channel in vitro. These observations raise the possibility that ThTP is part of a still uncharacterized cellular signaling pathway. On the other hand, its synthesis by a chemiosmotic mechanism in mitochondria and respiring bacteria might suggest a role in cellular energetics. [less ▲]

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See detailEffect of improved feeding and housing, Friesian blood level and parity on milk production of Ankole x Friesian cows
Kibwana, Denise Katungu; Makumyaviri, A.M.; Hornick, Jean-Luc ULg

in Pakistan Veterinary Journal (in press)

In North Kivu, D.R. Congo, cattle are raised in extensive systems based on local breeds and crossbreds. This farming method affects the performance of dairy animals and mortgages the level of milk ... [more ▼]

In North Kivu, D.R. Congo, cattle are raised in extensive systems based on local breeds and crossbreds. This farming method affects the performance of dairy animals and mortgages the level of milk consumption in population. An improved farming system, including feed supplementation, Friesian cross-breeding and the sheltering of animals in stalls at night, was studied to evaluate its effect on milk production by Ankole x Friesian crossbreds. The study was performed in Beni, D.R. Congo, on two groups of 15 animals (control group-CoG and improved group-IG), homogeneous according to Friesian blood and parity levels. The improved system, Friesian blood and parity levels increased significantly milk production (P<0.001). Farming system increased milk production by 1.6 l/d (5.2 l/d vs 6.8 l/d respectively in CoG and IG). Milk production ranged from 5.3±0.04 l/d to 6.6±0.02 l/d and from 4.9±0.02 l/d to 7.2±0.02 l/d according, respectively, to Friesian blood level and parity. A significant interaction was observed between farming system and Friesian blood level, and between farming system and parity (P<0.001). The two groups were characterized by a fair adaptation to forage availability associated to climatic factors. The study showed the importance of genetic and environmental factors on the milk production of crossbred dairy cows of the region. [less ▲]

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See detailA generic approach for solving nonlinear-discrete security-constrained power flow problems in large-scale systems
Platbrood, Ludovic; Capitanescu, Florin; Crisciu, Horia et al

in IEEE Transactions on Power Systems (in press)

This paper proves the practicality of an iterative algorithm for solving realistic large-scale SCOPF problems. This algorithm is based on the combination of a contingency filtering scheme, used to ... [more ▼]

This paper proves the practicality of an iterative algorithm for solving realistic large-scale SCOPF problems. This algorithm is based on the combination of a contingency filtering scheme, used to identify the binding contingencies at the optimum, and a network compression method, used to reduce the complexity of the post-contingency models included in the SCOPF formulation. We show that by combining these two complementary ideas, it is possible to solve in a reasonable time SCOPF problems on large power system models with a large number of contingencies. Unlike most results reported for large-scale SCOPF problems, our algorithm uses a non-linear AC network model in both pre-contingency and post-contingency states, optimizes both active/reactive powers flows jointly, and treats the discrete variables. The proposed algorithm is implemented with state-of-the-art solvers and applied to two systems: a national grid with 2563 buses and 1297 contingencies, and a model of the European transmission network with 9241 buses and 12000 contingencies. [less ▲]

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See detailA Geometrical Acoustics Approach Linking Surface Scattering and Reverberation in Room Acoustics
Embrechts, Jean-Jacques ULg

in Acta Acustica United with Acustica (in press)

A general model of the influence of surface scattering on the reverberation time would have several applications in room acoustics. Such a model is not yet available, and it is the purpose of this paper ... [more ▼]

A general model of the influence of surface scattering on the reverberation time would have several applications in room acoustics. Such a model is not yet available, and it is the purpose of this paper to investigate a geometrical acoustics approach. Starting from the radiative transfer equation, an exponential solution is first developed for the reverberation energy decay in rooms with diffusely reflecting boundaries. Differences with the diffuse sound field (Sabine) theory are highlighted, leading to a modified formula for the reverberation time which is shown to be more in accordance with ray tracing simulations. A general model is then proposed for rooms in which specular and diffuse reflections coexist. This general model is applied in rooms where the specular contribution can be assumed to be quasi-isotropic and uniform. Under this assumption, the reverberation decay is represented by the sum of two exponential functions, depending on the scattering coefficients. However, it is shown that the influence of surfaces’ scattering on reverberation is rather limited in this case. On the contrary, rooms with a pair of parallel surfaces are prone to create significant anisotropy in the cloud of image sources. An analytical formulation is proposed in this case for the specular and diffuse contributions, provided that some assumptions are again made on the specularly reflected sound field. The final expression is not really intuitive concerning the relation between scattering coefficients and reverberation, but it contains all the variables influencing this relation. This allows fast evaluations of the effect of surface scattering in particular situations. Finally, the application of this model to room acoustics computer simulations is illustrated by an example. [less ▲]

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See detailDes intentions aux actes : la volition en conseil d'orientation
Broonen, Jean-Paul ULg

in L'Orientation Scolaire et Professionnelle (in press)

A model limited to motivation construct to explain the way from setting a vocational goal to its achievement cannot claim to give an account of how to overcome regulatory problems during goal striving. A ... [more ▼]

A model limited to motivation construct to explain the way from setting a vocational goal to its achievement cannot claim to give an account of how to overcome regulatory problems during goal striving. A model linking volition to motivation is needed. In particular, implementation intentions have been proved to be effective in helping the initiation of goal striving, shielding goal pursuit from unwelcome influences, and disengagement from not successful courses of action. It is proposed to extend the application of this volitional cognitive tool to career counselling. [less ▲]

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See detailElaboration of drug nanocarriers based on a glucosamine labeled amphiphilic polymer
Boyère, Cédric; Duhem, N; Debuigne, Antoine ULg et al

in Polymer Chemistry (in press)

A new functional polymer micelle with high loading efficiency of a poorly soluble drug was made of biocompatible and/or biosourced compounds, i.e. cholesterol-poly(ethylene glycol)-glucosamine (Chol-PEG ... [more ▼]

A new functional polymer micelle with high loading efficiency of a poorly soluble drug was made of biocompatible and/or biosourced compounds, i.e. cholesterol-poly(ethylene glycol)-glucosamine (Chol-PEG-GlcNH2). A synthesis strategy combining enzymatic and metal-free click chemistry was developed in order to meet the increasingly stringent requirements of biomedical applications. After the self-assembly of the Chol-PEG-GlcNH2 amphiphilic polymer in water, the presence of glucosamine at the micelle surface confers an active targeting moiety to the nanocarriers whereas protonation of the peripheral primary amine delay their aggregation. The complete characterization of this novel functional amphiphilic bioconjugate is presented as well as its aqueous solution behaviour and encapsulation efficiency using ketoconazole as a model hydrophobic drug. [less ▲]

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See detailL'idéologie de la Nieuw‐Vlaamse Alliantie
Jamin, Jérôme ULg

in Revue européenne de géopolitique Outre-Terre (in press)

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See detailThe “Tuchlein” Colours in the Strasbourg Family Text: Recipes for Anthocyanin Pigments
Neven, Sylvie ULg; Sanyova, Jana

in Dyes in History and Archaeology (in press)

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See detailLes voyages du goût, entre localité et exotisme.
Mescoli, Elsa ULg

in Anthropology of Food: Fumey, G. ; Jackson, P. et Raffard, P. Culture Alimentaires et Territoires (in press)

« Savourer la nourriture et respirer la culture marocaine deviennent une expérience et une émotion unique, à découvrir et à vivre grâce à la combinaison d’arômes, goûts, couleurs, formes et musiques ». Au ... [more ▼]

« Savourer la nourriture et respirer la culture marocaine deviennent une expérience et une émotion unique, à découvrir et à vivre grâce à la combinaison d’arômes, goûts, couleurs, formes et musiques ». Au travers de ce slogan, un renommé restaurant d’inspiration marocaine de la ville de Milan en Italie, invitait ses clients à voyager au travers de leur sensorialité dans une culture alimentaire (et par synecdoque, une culture tout court) autre. Le goût les aurait amenés à expérimenter un exotisme, qui était néanmoins contrôlé, car certaines conditions imposées par les normes locales faisaient en sorte que le déplacement vécu ne fût pas excessivement déstabilisant. Le résultat de ces négociations consistait d’un menu qui accostait les gastronomies marocaine et italienne (ou les procédures de l’une et de l’autre) dans certains plats décrits comme « fusion », qui satisfaisaient (ou non) les exigences des clients. Dans cet article, je vise à mettre en évidence les mécanismes de production discursive et matérielle de ces plats, ainsi comme les opinions des consommateurs. Pour ce faire, j’analyserai le matériel ethnographique collecté auprès du local en question en le comparant avec les pratiques observés dans d’autres restaurants milanais. En ce qui concerne les effets obtenus, j’appuierait mon analyse sur une plateforme de médias sociaux consacrée aux recensions d’endroits et locaux touristiques. La culture alimentaire sera étudiée dans ses aspects symboliques mais aussi matériels, en faisant également recours au matériel visuel récolté. [less ▲]

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See detailPhysical controls on the storage of methane in landfast sea ice
Zhou, Jiayun ULg; Tison, J.-L.; Carnat, G. et al

in The Cryosphere (in press)

We report on methane (CH4) dynamics in landfast sea ice, brine and under-ice seawater at Barrow in 2009. The CH4 concentrations in under-ice water ranged between 25.9 and 116.4 nmol L-1sw, indicating a ... [more ▼]

We report on methane (CH4) dynamics in landfast sea ice, brine and under-ice seawater at Barrow in 2009. The CH4 concentrations in under-ice water ranged between 25.9 and 116.4 nmol L-1sw, indicating a supersaturation of 700 to 3100 % relative to the atmosphere. In comparison, the CH4 concentrations in sea ice, ranged between 3.4 and 17.2 nmol L-1ice, and the deduced CH4 concentrations in brine, between 13.2 and 677.7 nmol L-1brine. We investigated on the processes explaining the difference in CH4 concentrations between sea ice, brine and the under-ice water, and suggest that biological controls on the storage of CH4 in ice was minor in comparison to the physical controls. Two physical processes regulated the storage of CH4 in our landfast ice samples: bubble formation within the ice and sea ice permeability. Gas bubble formation from solubility changes had favoured the accumulation of CH4 in the ice at the beginning of ice growth. CH4 retention in sea ice was then twice as efficient as that of salt; this also explains the overall higher CH4 concentrations in brine than in the under-ice water. As sea ice thickened, gas bubble formation became less efficient, CH4 was then mainly trapped in the dissolved state. The increase of sea ice permeability during ice melt marked the end of CH4 storage. [less ▲]

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See detailA Super-Jupiter orbiting a late-type star: A refined analysis of microlensing event OGLE-2012-BLG-0406
Tsapras, Y.; Choi, J.-Y.; Street, R. A. et al

in Astrophysical Journal (in press)

We present a detailed analysis of survey and follow-up observations of microlensing event OGLE-2012-BLG-0406 based on data obtained from 10 different observatories. Intensive coverage of the lightcurve ... [more ▼]

We present a detailed analysis of survey and follow-up observations of microlensing event OGLE-2012-BLG-0406 based on data obtained from 10 different observatories. Intensive coverage of the lightcurve, especially the perturbation part, allowed us to accurately measure the parallax effect and lens orbital motion. Combining our measurement of the lens parallax with the angular Einstein radius determined from finite-source effects, we estimate the physical parameters of the lens system. We find that the event was caused by a $2.73\pm 0.43\ M_{\rm J}$ planet orbiting a $0.44\pm 0.07\ M_{\odot}$ early M-type star. The distance to the lens is $4.97\pm 0.29$\ kpc and the projected separation between the host star and its planet at the time of the event is $3.45\pm 0.26$ AU. We find that the additional coverage provided by follow-up observations, especially during the planetary perturbation, leads to a more accurate determination of the physical parameters of the lens. [less ▲]

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See detailDe l’usage de la photographie dans une enquête ethno-sociologique sur la mémoire de l’exil et de l’immigration espagnols en Belgique
Molina Marmol, Maïté ULg

in RELAIS Revue du laboratoire d'études et de recherches sur l'interculturel (in press)

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See detailProposed terms and concepts for describing and evaluating animal-health surveillance systems
Hoinville, LJ; Alban, L; Drewe, JA et al

in Preventive Veterinary Medicine (in press)

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See detailOceanic forcing of Antarctic climate change: A study using a stretched-grid atmospheric general circulation model
Krinner, Gerhard; Largeron, Chloé; Ménégoz, Martin et al

in Journal of Climate (in press)

A variable-resolution atmospheric general circulation model (AGCM) is used for climate change projections over the Antarctic. The present-day simulation uses prescribed observed sea-surface conditions ... [more ▼]

A variable-resolution atmospheric general circulation model (AGCM) is used for climate change projections over the Antarctic. The present-day simulation uses prescribed observed sea-surface conditions, while a set of five simulations for the end of the 21st century (2070-2099) under the SRES-A1B scenario uses sea- surface condition anomalies from selected CMIP3 coupled ocean-atmosphere climate models. Analysis of the results shows that the prescribed sea-surface condition anomalies have a very strong influence on the simulated climate change on the Antarctic continent, largely dominating the direct effect of the prescribed greenhouse gas concentration changes in the AGCM simulations. Complementary simulations with idealized forcings confirm these results. An analysis of circulation changes using self-organizing maps shows that the simulated climate change on regional scales is not principally caused by shifts of the frequencies of the dominant circulation patterns, except for precipitation changes in some coastal regions. The study illustrates that in some respects the use of bias-corrected sea- surface boundary conditions in climate projections with a variable-resolution atmospheric general circulation model has some distinct advantages over the use of limited-area atmospheric circulation models directly forced by generally biased coupled climate model output. [less ▲]

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See detailLes niveaux d'analyse dans la microstructure de l'Atlas linguistique de la Wallonie
Baiwir, Esther ULg

in Estudis Romànics (in press), 36

Le lecteur de l'ALW constate rapidement que les formes phonétiques n'y sont pas livrées brutes sur des cartes, comme dans les atlas de France par région, ni sous forme de liste, mais bien dans une ... [more ▼]

Le lecteur de l'ALW constate rapidement que les formes phonétiques n'y sont pas livrées brutes sur des cartes, comme dans les atlas de France par région, ni sous forme de liste, mais bien dans une présentation structurée en paragraphes, regroupant selon des critères variables des formes phonétiques distinctes. Après avoir proposé une schématisation de la microstructure du projet, sur base d'une notice-modèle (1), nous détaillerons ces critères de classement (phonologique, morphologique, syntaxique, étymologique, motivationnel ou encore sémantique; 2). Chaque paragraphe de matériaux porte un titre, qui représente d'une façon plus ou moins abstraite les matériaux qu'il comporte. Ce titre peut prendre différentes formes: une orthographe dite « Feller » ou des types reconstruits plus abstraits. Nous tenterons de montrer en quoi ces deux images très différentes des matériaux ne sont pas réductibles l'une à l'autre (3). [less ▲]

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See detailDevonian antiarch placoderms from Belgium revisited
Olive, Sébastien ULg

in Acta Palaeontologica Polonica (in press)

Anatomical, systematic, and paleobiogeographical data on the Devonian antiarchs from Belgium are reviewed, updated and completed thanks to new data from the field and re-examination of paleontological ... [more ▼]

Anatomical, systematic, and paleobiogeographical data on the Devonian antiarchs from Belgium are reviewed, updated and completed thanks to new data from the field and re-examination of paleontological collections. The material of Bothriolepis lohesti Leriche, 1931 is enhanced and the species better described. An undetermined species of Bothriolepis is recorded from the Famennian of Modave (Liège Province), one species of Asterolepis redescribed from the Givetian of Hingeon and another one described from the Givetian of Mazy (Namur Province). Grossilepis rikiki sp. nov. is recorded from the Famennian tetrapod-bearing locality of Strud (Namur Province) and from the Famennian of Moresnet (Liège Province). It is the first occurrence of Grossilepis after the Frasnian and on the central southern coast of the Euramerican continent. Its occurrence in the Famennian of Belgium may be the result of a late arrival from the Moscow Platform and the Baltic Depression, where the genus is known from Frasnian deposits. Remigolepis durnalense sp. nov. is described from the Famennian of Spontin near Durnal (Namur Province). Except for the doubtful occurrence of Remigolepis sp. in Scotland, this is the first record of this genus in Western Europe. Its occurrence in Belgium reinforces the strong faunal affinities between Belgium and East Greenland and the hypothesis of a hydrographical link between the two areas during the Late Devonian. [less ▲]

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See detailLe Fonds Hubert Nyssen à l'Université de Liège
Durand, Pascal ULg; Habrand, Tanguy ULg

in Histoires littéraires (in press)

Biographie croisée de l'écrivain et de l'éditeur Hubert Nyssen et présentation détaillée du Fonds d'archives déposé par lui au Centre d'Etude du Livre Contemporain de l'Université de Liège.

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See detailMulti-period vehicle loading with stochastic release dates
Arda, Yasemin ULg; Crama, Yves ULg; Kronus, David ULg et al

in EURO Journal on Transportation and Logistics (in press)

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be ... [more ▼]

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be formulated as a large-scale set covering problem. Several heuristic algorithms are proposed to generate decision policies for the stochastic optimization model over a long rolling horizon. The resulting policies have been extensively tested on instances which display the main characteristics of the industrial case-study that motivated the research. The tests demonstrate the benefits of the multi-period stochastic model over simple myopic strategies. A simple and efficient heuristic is shown to deliver good policies and to be robust against errors in the estimation of the probability distribution of the release dates. [less ▲]

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See detailType I error inflation in DIF identification with Mantel-Haenszel: an explanation and a solution
Magis, David ULg; De Boeck, Paul

in Educational & Psychological Measurement (in press)

It is known that sum score-based methods for the identification of differential item functioning (DIF), such as the Mantel-Haenszel (MH) approach, can be affected by Type I error inflation in the absence ... [more ▼]

It is known that sum score-based methods for the identification of differential item functioning (DIF), such as the Mantel-Haenszel (MH) approach, can be affected by Type I error inflation in the absence of any DIF effect. This may happen when the items differ in discrimination and when there is item impact. On the other hand, outlier DIF methods have been developed that are robust against this Type I error inflation, while they are still based on the MH DIF statistic. The present paper gives an explanation for why the common MH method is indeed vulnerable to the inflation effect while the outlier DIF versions are not. In a simulation study we were able to produce the Type I error inflation by inducing item impact and item differences in discrimination. At the same time and in parallel with the Type I error inflation the dispersion of the DIF statistic across items was increased. As expected, the outlier DIF methods did not seem sensitive to impact and differences in item discrimination. [less ▲]

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See detailEL TLC UE – Colombia – Perú y la integración regional latinoamericana. ¿Hacia una norteamericanización de la estrategia interregional europea?
Parra Santamaria, Lusmiriam Andrea ULg

in Comentario Internacional (in press)

This document compares the contents of the Free Trade Agreements (FTA) that have been signed by the European Union and by the United States with Colombia. It analyses them from a perspective that ... [more ▼]

This document compares the contents of the Free Trade Agreements (FTA) that have been signed by the European Union and by the United States with Colombia. It analyses them from a perspective that characterizes FTAs into “WTO-extra” and “WTO-plus” agreements. By this analysis, an “Americanization” of the European interregional strategy is partially verified. Nevertheless, this “Americanization” appears to be partial, due to the inclusion of “regional integration” as a transversal theme in European FTA. [less ▲]

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See detailThe Third/Second Generation PTH Assay Ratio as a Marker for Parathyroid Carcinoma: Evaluation Using an Automated Platform
CAVALIER, Etienne ULg; BETEA, Daniela ULg; SCHLECK, Marie-Louise ULg et al

in Journal of Clinical Endocrinology and Metabolism (in press)

Background: Parathyroid carcinoma (PCa) is rare and often difficult to differentiate initially from benign disease. Because PCa oversecretes amino PTH that is detected by third-generation but not by ... [more ▼]

Background: Parathyroid carcinoma (PCa) is rare and often difficult to differentiate initially from benign disease. Because PCa oversecretes amino PTH that is detected by third-generation but not by second-generation PTH assays, the normal generation PTH ( 1) is inverted in PCa (ie, 1). Objective: The objective of the investigation was to study the utility and advantages of automated generation PTH ratio measurements using the Liaison XL platform over existing manual techniques. Setting: The study was conducted at a tertiary-referral academic center. Design: This was a retrospective laboratory study. Subjects: Eleven patients with advanced PCa (mean age 56.0 y). The controls were patients with 1°-hyperparathyroidism (n 144;meanage 53.8 y), renal transplantation (n 41;meanage 50.6 y), hemodialysis (n 80; mean age 65.2 y), and healthy elderly subjects (n 40; mean age 72.6 y). Results: The median (interquartile range) generation PTH ratio was 1.16 (1.10 –1.38) in the PCa group, which was significantly higher than the control groups: 0.74 (hemodialysis, 0.71–0.75), 0.77 (renal transplant, 0.73–0.79), 0.80 (healthy elderly, 0.74–0.83), and 0.76 (1°-hyperparathyroidism, 0.74–0.78). An inverted -generation PTH ratio ( 1) was seen in 9 of 11 PCa patients (81.8%) and in 7 of 305 controls (2.3%), 3 of 80 hemodialysis (3.8%), and 4 of 144 1°-hyperparathyroidism patients (2.8%). Of four PCa patients who had a normal PTH ratio with the manual method, two had an inverted -generation PTH ratio with the automated method. Conclusions: Study of the -generation PTH ratio in large patient populations should be feasible using a mainstream automated platform like the Liaison XL. The current study confirms the utility of the inverted -generation PTH ratio as a marker of PCa (sensitivity: 81.8%; specificity: 97.3%). [less ▲]

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See detailAberrations chromatiques : de l’émulsion au pixel
Thonon, Jonathan ULg

in Cahiers Louis Lumière (in press)

Dans l’une de ses conversations avec Joachim Gasquet sur le sens de sa peinture (et de la peinture en général), Cézanne aborde de front la conception qu’il se fait de la couleur, dans son rapport à la ... [more ▼]

Dans l’une de ses conversations avec Joachim Gasquet sur le sens de sa peinture (et de la peinture en général), Cézanne aborde de front la conception qu’il se fait de la couleur, dans son rapport à la profondeur picturale et de son articulation à la surface : « La nature n'est pas en surface ; elle est en profondeur. Les couleurs sont l'expression, à cette surface, de cette profondeur. Elles montent des racines du monde ». Cet « organisme de couleurs » que constitue le monde est transcrit dans la peinture de Cézanne par une dynamique symbiotique de la couleur et du dessin, de la ligne et du pan. La couleur restitue, par sa masse, son surgissement, son homogénéité, presque sa viscosité, la véritable chaire perceptive du monde ; une vision qui tient à distance la perspective géométrique, photographique, cinématographique fondée sur la transparence et qui repose, comme le signale Merleau-Ponty, sur la « réversibilité des dimensions » (surface-profondeur) et l’entrelacement des choses. C’est cette épaisseur du visible rendu par la couleur que l’économie de l’image numérique nous permet de redécouvrir, moins dans le registre de la « tactilité » de l’image et la picturalité du pixel, que par l’intégration, entre le support et l’image (parfois indiscernables dans le régime optique), d’un « corps » algorithmique qui règle l’actualisation du visible. Certains défauts techniques du dispositif numérique, aujourd’hui élevés au rang de pratique artistique, permettent de révéler cette matrice qui utilise alors la couleur et la coulure comme mode de visibilité. C’est le cas du Datamoshing, technique de composition numérique qui revisite tout en la radicalisant la pratique de l’incrustation vidéo. Basée sur la perturbation volontaire d’éléments de la matrice, cette technique transforme les couleurs en une forme malléable et fluide révélant ainsi leur double nature spatiale : elles sont à la fois dans l’espace de l’image et l’espace de l’image lui-même. Ces expériences de défigurations d’images s’inscrivent dans le registre des « aberrations chromatiques » dont nous proposons ici une rapide généalogie avant d’interroger la couleur digitale dans ses spécificités. [less ▲]

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See detailVirtual reality as a complementary therapy to sexual addiction treatment
Cismaru Inescu, Adina; Andrianne, Robert ULg; Triffaux, Jean-Marc ULg

in International Journal of Advanced Computer Science (in press), 3(7), 1-5

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See detailL'espace transitionnel winnicotien et l'_Urraum_ kantien
Seba, Jean-Renaud ULg

in Revista Natureza Humana (in press)

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See detailMoyens et enjeux d’une approche didactique des Illuminations
Saint-Amand, Denis ULg

in Parade Sauvage (in press), 25

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See detailSegregation distortions in an interspecific cotton population issued from the [(Gossypium hirsutum x G. raimondii)² x G. sturtianum] hybrid
Diouf, Fatimata Bintou Hassédine ULg; BENBOUZA, Halima; Nacoulima, Nafissatou Lalaïssa ULg et al

in Tropicultura (in press)

The segregation ratio of 10 Gossypium sturtianum specific SSR markers belonging to linkage groups c2-c14, c3-c17, and c6-c25was analysed in the BC2S6 progeny of the [G.hirsutum x G. raimondii)² x G ... [more ▼]

The segregation ratio of 10 Gossypium sturtianum specific SSR markers belonging to linkage groups c2-c14, c3-c17, and c6-c25was analysed in the BC2S6 progeny of the [G.hirsutum x G. raimondii)² x G. sturtianum] (HRS) hybrid; based on chi-square test. All the marker loci tested were associated with skewed allele frequencies (P < 0.001) showing a strong SD with a zygotic selection. The possible causes and consequences of this massive segregation distortion are discussed [less ▲]

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See detailAllogeneic stem cell transplantation for advanced cutaneous T-cell lymphomas: a study from the French Society of Bone Marrow Transplantation and French Study Group on Cutaneous Lymphomas
de Masson, Adele; Beylot-Barry, Marie; Bouaziz, Jean-David et al

in Haematologica (in press)

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See detailA simulation study comparing multiple imputation methods for incomplete longitudinal ordinal data
Donneau, Anne-Françoise ULg; Mauer, Murielle; Molenberghs, Geert et al

in Communications in Statistics : Simulation & Computation (in press)

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See detailLes ambiguïtés de l’anthropomorphisme : de la divinité agissante à sa statue dans la céramique grecque
Collard, Hélène ULg

in MethIS : Méthodes et Interdisciplinarité en Sciences Humaines (in press)

L’image, sous ses divers aspects, a joué un rôle essentiel dans la vie des anciens Grecs, en particulier dans le domaine religieux, puisque elle était l’une des modalités de perception du divin. En Grèce ... [more ▼]

L’image, sous ses divers aspects, a joué un rôle essentiel dans la vie des anciens Grecs, en particulier dans le domaine religieux, puisque elle était l’une des modalités de perception du divin. En Grèce, la figuration anthropomorphe des dieux est largement majoritaire. Toutefois, en se tournant vers un support particulier, le vase peint, et un type de représentation particulier, la statue divine, on montrera ici que l’anthropomorphisme a pu amener une certaine ambiguïté. Dans la céramique, les représentations de statues fonctionnent sur plusieurs modes, selon la chronologie. C’est ce que l’on propose d’analyser, en examinant un groupe de vases décorés d’un thème semblable et sur lesquels une divinité est représentée, mais soit sous la forme d’une figure « vivante », soit d’une statue plus ou moins bien caractérisée. Cette étude permettra d’aborder les concepts de « fixité » et de « mouvement » de/dans l’image, mais aussi d’explorer quelques pistes de réflexions sur l’image divine et, plus largement, sur les modes de représentation du divin en Grèce ancienne. [less ▲]

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See detailThe ideology of the British National Party
Jamin, Jérôme ULg

in Revue LISA : Littératures, Histoire des Idées, Images, Sociétés du Monde Anglophone = LISA e-Journal (in press)

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See detailBuilding on anticipation: dystopia as empowerment
Claisse, Frédéric ULg; Delvenne, Pierre ULg

in Current Sociology (2015), 63(2),

A dystopia can be defined as the depiction of a dark future building on the systematic amplification of current trends and features. It relates to a complex narrative posture that relies on the critical ... [more ▼]

A dystopia can be defined as the depiction of a dark future building on the systematic amplification of current trends and features. It relates to a complex narrative posture that relies on the critical observation of a threatening present that would lead to an apocalyptic future “if nothing was done.” Yet, however inescapable this future may be described, the very existence of such a narrative presupposes that the political community it tries to reach is actually able to do something to thwart it. Oddly enough, a successful dystopia aims at making itself obsolete: once the world it depicts is identified as a possible (or even unavoidable) future, it seems to empower its readers again, restoring what Musil called a ‘sense of possibilities’ that eventually make alternative pathways thinkable. In our contribution, we propose to broaden the range of commonly accepted dystopists (usually fiction writers and novelists like e.g. George Orwell’s 1984) to sociologists like Ulrich Beck. Building on his Risk Society (1986), Beck’s strong diagnosis about the breakdown of First Modernity and the coming of Second Modernity contains a noticeable prophetic and evangelical overtone that aims at “reinventing politics.” We defend the notion that the dystopian posture can be used to characterize both fiction and nonfiction writers such as Orwell and Beck: a common ability, based on the same set of inextricably cognitive and normative patterns, to anticipate the future and eventually empower political communities to engage in further action. [less ▲]

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See detailRobust optimization for resource-constrained project scheduling with uncertain activity durations
Artigues, Christian; Leus, Roel; Talla Nobibon, Fabrice ULg

in Flexible Services and Manufacturing Journal (2015), 25(1-2),

The purpose of this paper is to propose models for project scheduling when there is considerable uncertainty in the activity durations, to the extent that the decision maker cannot with confidence ... [more ▼]

The purpose of this paper is to propose models for project scheduling when there is considerable uncertainty in the activity durations, to the extent that the decision maker cannot with confidence associate probabilities with the possible scenarios. Our modeling techniques stem from robust optimization, which is a theoretical framework that enables the decision maker to produce solutions that will have a reasonably good objective value under any likely input data scenario. We develop and implement a scenario-relaxation algorithm and a scenario-relaxationbased heuristic. The first algorithm produces optimal solutions but requires excessive running times even for medium-sized instances; the second algorithm produces high-quality solutions for medium-sized instances and outperforms two benchmark heuristics. [less ▲]

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See detailGiven to a Deity? Religious and Social Reappraisal of Human Consecrations in the Hellenistic and Roman East
Caneva, Stefano ULg; Delli Pizzi, Aurian ULg

in Classical Quarterly (2015)

Various cases of human beings ‘dedicated’ to deities are attested in Greek epigraphic evidence. Are these kinds of offerings comparable to the dedication of inanimate objects? Besides, does the fact that ... [more ▼]

Various cases of human beings ‘dedicated’ to deities are attested in Greek epigraphic evidence. Are these kinds of offerings comparable to the dedication of inanimate objects? Besides, does the fact that someone is said to be ‘sacred’ to a specific deity necessarily involve that he went through a process of dedication? This article aims at providing a global picture of different situations in which processes of dedications took place. Among the several issues that are tackled, the cornerstone of this article consists of two questions: for what purposes did some people decide to consecrate a human being to a deity and what were the consequences for the consecrated individuals on religious and social levels? Different categories of persons will be contrasted, in terms of processes through which they acquire their new status but also in terms of the freedom/lack of freedom which is conveyed by this new status. It will also be shown that, as far as method is concerned, it is necessary to complete a lexical analysis with a contextual perspective for a deeper understanding of the problem. [less ▲]

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See detailRitournelles et territoires professionnels. Le cas des conseillers emploi
Orianne, Jean-François ULg

in Langage et Société (2015)

L’objectif de ce texte est d’utiliser le concept de ritournelle pour analyser la formation d’un groupe professionnel dans le champ des politiques d’emploi en Belgique : les conseillers emploi du FOREM ... [more ▼]

L’objectif de ce texte est d’utiliser le concept de ritournelle pour analyser la formation d’un groupe professionnel dans le champ des politiques d’emploi en Belgique : les conseillers emploi du FOREM. L’auteur commence par définir et opérationnaliser le concept, emprunté à Deleuze et Guattari, en suivant les apports des théories de la communication réflexive. Il esquisse brièvement le contexte politique et institutionnel au sein duquel le groupe professionnel apparaît. Ensuite, il analyse trois ritournelles professionnelles, trois procédés de territorialisation des identités professionnelles des conseillers emploi. Il précise, en conclusion, la complémentarité du concept de ritournelle avec celui de rhétorique professionnelle. [less ▲]

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See detailInstitutional Investors, Information Asymmetry, Stock Market Liquidity
Sougné, Danielle ULg; Aymen, Ajina; Faten, Lakhal

in International Journal of Managerial Finance (2015), 11

The purpose of this study is to examine the effect of institutional investors' ownership and activism on information asymmetry and stock market liquidity in France.

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See detailLes porcheries : réservoirs des culicoïdes (Diptera: Ceratopogonidae), vecteurs des virus de la Maladie de la Langue bleue et de Schmallenberg ?
Zimmer, Jean-Yves ULg; Saegerman, Claude; Martinelle, Ludovic et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014)

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See detailMultilocus sequence typing analysis and antibiotic resistance of Clostridium difficile strains isolated from retail meat and humans in Belgium
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Avesani, Véronique et al

in Food Microbiology (2014), 42

Clostridium difficile has been isolated from food animals and meat, specially ground pork and ground beef. The recovered isolates were closely related to C. difficile human strains, indicating that ... [more ▼]

Clostridium difficile has been isolated from food animals and meat, specially ground pork and ground beef. The recovered isolates were closely related to C. difficile human strains, indicating that animals and food are possible transmission routes of human C. difficile infection. The main objective of this study was to characterize C. difficile isolates from retail meat and to compare with human isolates recovered from hospital patients in Belgium. Raw meat (beef and pork) was obtained from the retail trade. C. difficile was recovered from 2.3% of the beef samples and from 4.7% of the pork samples. A total of 4 different PCR-ribotypes were identified with a large percentage of types 078 and 014. Resistance to moxifloxacin and erythromycin was detected. The multi-locus sequence typing (MLST) analysis showed that meat and human isolates cluster in the same lineage. This study reveals the presence of toxigenic C. difficile in retail meat in Belgium with predominance PCR-ribotypes 078 and 014, which are among the four most prevalent ribotypes of C. difficile isolated from humans in Europe. [less ▲]

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See detailHow to correctly determine the kinetics of a photocatalytic degradation reaction?
Pirard, Sophie ULg; Malengreaux, Charline ULg; Toye, Dominique ULg et al

in Chemical Engineering Journal (2014), 249

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See detailLe TAT de Adolf Eichmann
Peralta, Alberto; Kramer, Richard; Stassart, Martine ULg

in Szondiana (2014)

Under consideration of three major personality tests (TAT, Rorschach, Szondi), it appears that Adolf Eichmann chiefdirector for the deportation of jewish people from 1942 to 1945 was no common individual ... [more ▼]

Under consideration of three major personality tests (TAT, Rorschach, Szondi), it appears that Adolf Eichmann chiefdirector for the deportation of jewish people from 1942 to 1945 was no common individual but a perverse sadomasochistic one with schizoparanoïd features under an osessionnal mask. These data contradict the famous opinion of Hannah Arendt about the "banality of evil". [less ▲]

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See detailComparison of centralized, distributed and hierarchical model predictive control schemes for electromechanical oscillations damping in large-scale power systems
Wang, Da ULg; Glavic, Mevludin ULg; Wehenkel, Louis ULg

in International Journal of Electrical Power & Energy Systems (2014), 58

The paper investigates the feasibility of applying Model Predictive Control (MPC) as a viable strategy to damp wide-area electromechanical oscillations in large-scale power systems. First a fully ... [more ▼]

The paper investigates the feasibility of applying Model Predictive Control (MPC) as a viable strategy to damp wide-area electromechanical oscillations in large-scale power systems. First a fully centralized MPC scheme is considered, and its performances are evaluated first in ideal conditions and then by considering state estimation errors and communication delays. This scheme is further extended into a distributed scheme with the aim of making it more viable for very large-scale or multi-area systems. Finally, a robust hierarchical multi-area MPC scheme is proposed, introducing a second layer of MPC based controllers at the level of individual power plants and transmission lines. Simulations are carried out using a 70-bus test system. The results reveal all three MPC schemes as viable solutions to supplement existing controllers in order to improve the system performance in terms of damping. The hierarchical scheme is the one combining the best performances in nominal conditions and the best robustness with respect to partial component failures and various modeling and measurement errors. [less ▲]

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See detailSocial Security and Economic Integration
Artige, Lionel ULg; Dedry, Antoine ULg; Pestieau, Pierre ULg

in Economics Letters (2014), 123(June), 318-322

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See detailComputational homogenization of cellular materials
Nguyen, Van Dung ULg; Noels, Ludovic ULg

in International Journal of Solids and Structures (2014), 51(11-12), 2183-2203

In this work we propose to study the behavior of cellular materials using a second–order multi–scale computational homogenization approach. During the macroscopic loading, micro-buckling of thin ... [more ▼]

In this work we propose to study the behavior of cellular materials using a second–order multi–scale computational homogenization approach. During the macroscopic loading, micro-buckling of thin components, such as cell walls or cell struts, can occur. Even if the behavior of the materials of which the micro–structure is made remains elliptic, the homogenized behavior can lose its ellipticity. In that case, a localization band is formed and propagates at the macro–scale. When the localization occurs, the assumption of local action in the standard approach, for which the stress state on a material point depends only on the strain state at that point, is no–longer suitable, which motivates the use of the second-order multi–scale computational homogenization scheme. At the macro–scale of this scheme, the discontinuous Galerkin method is chosen to solve the Mindlin strain gradient continuum. At the microscopic scale, the classical finite element resolutions of representative volume elements are considered. Since the meshes generated from cellular materials exhibit voids on the boundaries and are not conforming in general, the periodic boundary conditions are reformulated and are enforced by a polynomial interpolation method. With the presence of instability phenomena at both scales, the arc–length path following technique is adopted to solve both macroscopic and microscopic problems. [less ▲]

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See detailForest radiative transfer models: which approach for which application?
Ligot, Gauthier ULg; Balandier, Philippe; Courbaud, Benoît et al

in Canadian Journal of Forest Research = Journal Canadien de la Recherche Forestière (2014), 44(5), 385-397

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See detailThe XMM-Newton view of the yellow hypergiant IRC+10420 and its surroundings
De Becker, Michaël ULg; Hutsemekers, Damien ULg; Gosset, Eric ULg

in New Astronomy (2014), 29

Among evolved massive stars likely in transition to the Wolf-Rayet phase, IRC +10420 is probably one of the most enigmatic. It belongs to the category of yellow hypergiants and it is characterized by ... [more ▼]

Among evolved massive stars likely in transition to the Wolf-Rayet phase, IRC +10420 is probably one of the most enigmatic. It belongs to the category of yellow hypergiants and it is characterized by quite high mass loss episodes. Even though IRC+10420 benefited of many observations in several wavelength domains, it has never been a target for an X-ray observatory. We report here on the very first dedicated observation of IRC+10420 in X-rays, using the XMM-Newton satellite. Even though the target is not detected, we derive X-ray flux upper limits of the order of 1–3 ×10−14 erg cm−2 s−1 (between 0.3 and 10.0 keV), and we discuss the case of IRC+10420 in the framework of emission models likely to be adequate for such an object. Using the Optical/UV Monitor on board XMM-Newton, we present the very first upper limits of the flux density of IRC +10420 in the UV domain (between 1800 and 2250 Å and between 2050 and 2450 Å). Finally, we also report on the detection in this field of 10 X-ray and 7 UV point sources, and we briefly discuss their properties and potential counterparts at longer wavelengths. [less ▲]

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See detailHeterochrony in a complex world: disentangling environmental processes of facultative paedomorphosis in an amphibian
Denoël, Mathieu ULg; Ficetola, Gentile Francesco

in Journal of Animal Ecology (2014), 83(606-615),

1. Heterochrony, the change in the rate or timing of development between ancestors and their descendants, plays a major role in evolution. When heterochrony produces polymorphisms, it offers the ... [more ▼]

1. Heterochrony, the change in the rate or timing of development between ancestors and their descendants, plays a major role in evolution. When heterochrony produces polymorphisms, it offers the possibility to test hypotheses that could explain its success across environments. Amphibians are particularly suitable to exploring these questions because they express complex life cycles (i.e. metamorphosis) that have been disrupted by heterochronic processes (paedomorphosis: retention of larval traits in adults). The large phenotypic variation across populations suggests that more complex processes than expected are operating, but they remain to be investigated through multivariate analyses over a large range of natural populations across time. 2. In this study we compared the likelihood of multiple potential environmental determinants of heterochrony. We gathered data on the proportion of paedomorphic and metamorphic palmate newts (Lissotriton helveticus) across more than 150 populations during 10 years, and used an information-theoretic approach to compare the support of multiple potential processes. 3. Six environmental processes jointly explained the proportion of paedomorphs in populations: predation, water availability, dispersal limitation, aquatic breathing, terrestrial habitat suitability, and anti-predator refuges. Analyses of variation across space and time supported models based on the advantage of paedomorphosis in favourable aquatic habitats. 4. Paedomorphs were favoured in deep ponds, in conditions favourable to aquatic breathing (high oxygen content), with lack of fish, and surrounded by suitable terrestrial habitat. Metamorphs were favoured by banks allowing easy dispersal. 5. These results indicate that heterochrony relies on complex processes involving multiple ecological variables and exemplifies why heterochronic patterns occur in contrasted environments. On the other hand, the fast selection of alternative morphs shows that metamorphosis and paedomorphosis developmental modes could be easily disrupted in natural populations. [less ▲]

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See detailTransit confirmation and improved stellar and planet parameters for the super-Earth HD 97658 b and its host star
Van Grootel, Valérie ULg; Gillon, Michaël ULg; Valencia, D. et al

in Astrophysical Journal (2014), 786

Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition ... [more ▼]

Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition. We present here the confirmation, based on Spitzer transit observations, that the super-Earth HD 97658 b transits its host star. HD 97658 is a low-mass ($M_*=0.77\pm0.05\,M_{\odot}$) K1 dwarf, as determined from the Hipparcos parallax and stellar evolution modeling. To constrain the planet parameters, we carry out Bayesian global analyses of Keck-HIRES radial velocities, and MOST and Spitzer photometry. HD 97658 b is a massive ($M_P=7.55^{+0.83}_{-0.79} M_{\oplus}$) and large ($R_{P} = 2.247^{+0.098}_{-0.095} R_{\oplus}$ at 4.5 $\mu$m) super-Earth. We investigate the possible internal compositions for HD 97658 b. Our results indicate a large rocky component, by at least 60% by mass, and very little H-He components, at most 2% by mass. We also discuss how future asteroseismic observations can improve the knowledge of the HD 97658 system, in particular by constraining its age. Orbiting a bright host star, HD 97658 b will be a key target for coming space missions TESS, CHEOPS, PLATO, and also JWST, to characterize thoroughly its structure and atmosphere. [less ▲]

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See detailX-ray microtomography: A porosity-based thresholding method to improve soil pore network characterization?
Beckers, Eléonore ULg; Plougonven, Erwan ULg; Roisin, Christian et al

in Geoderma (2014), 219-220

X-ray microtomography, through quantification of soil structure at the microscale, could greatly facilitate the current understanding of soil hydrodynamic behaviour. However, binarisation method and ... [more ▼]

X-ray microtomography, through quantification of soil structure at the microscale, could greatly facilitate the current understanding of soil hydrodynamic behaviour. However, binarisation method and processing choices are subjective and can have a strong impact on results and conclusions. In this study, we test a new method based on the porosity detectable by X-ray microtomography, while validation is achieved through comparison of soil microtomogram information with soil physical measurements. These measurements consist of water retention and unsaturated hydraulic conductivity using two different soil populations with only structural differences. To assess the porosity-based method performances, we compare it to four other methods, namely the global method of Otsu and three recent soil-dedicated local methods. The robustness of the porosity-based method is also tested in regard to different pre-processing procedures. In this paper we demonstrate that soil segmentation through a porosity-based method is an interesting issue. Indeed, it is less demanding in terms of time and computational requirements than its alternatives, and combines robustness and performances broadly comparable with the recent local methods. [less ▲]

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See detailAnalysis of transient scattering problems using a discontinuous Galerkin method: application to the shielding effectiveness of enclosures with heterogeneous walls
Boubekeur, Mohamed; Kameni, Abelin; Pichon, Lionel et al

in International Journal of Numerical Modelling: Electronic Networks, Devices and Fields (2014), 27(3), 626-635

In this paper, different formulations of Maxwell equations are combined for computing the shielding effectiveness of enclosures made from heterogeneous periodic materials. The validity of the homogenized ... [more ▼]

In this paper, different formulations of Maxwell equations are combined for computing the shielding effectiveness of enclosures made from heterogeneous periodic materials. The validity of the homogenized parameters given by Maxwell-Garnett rules in the frequency domain are tested in the time domain using a nodal discontinuous Galerkin method, which uses an interface condition based on analytical solution in the frequency domain to replace a conductive sheet. This interface condition allows to avoid meshing the thin sheet, thus reducing the computational cost. Results of scattering by composite enclosures are presented in the frequency domain thanks to a Fast Fourier Transform. [less ▲]

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See detailTendinopathies chroniques et Plasma Riche en Plaquettes
KAUX, Jean-François ULg; Drion, Pierre ULg; Croisier, Jean-Louis ULg et al

in Revue Médicale de Liège (2014)

Platelets contain growth factors released during their degranulation following activation. These growth factors promote tissue remodeling, wound healing and angiogenesis. Currently, the clinical effect of ... [more ▼]

Platelets contain growth factors released during their degranulation following activation. These growth factors promote tissue remodeling, wound healing and angiogenesis. Currently, the clinical effect of Platelet-Rich Plasma (PRP) is still discussed or even controversial. Our researches have evaluated the effectiveness of PRP on the healing of animal tendons and human suffering from chronic jumper's knee. [less ▲]

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See detailPreparation of polyaniline-modified local clay and study of its sorption capacity
Benhebal, Hadj; Chaid, Messaoud; Léonard, Angélique ULg et al

in Journal of Nanostructure in Chemistry (2014), 4(98), 6

Clay minerals are frequently used in adsorption processes with aqueous solution; it was found that the adsorption properties of clays change when the samples are modified. In this context, polyaniline ... [more ▼]

Clay minerals are frequently used in adsorption processes with aqueous solution; it was found that the adsorption properties of clays change when the samples are modified. In this context, polyaniline-modified clay nanocomposite (at 10 %) was prepared by in situ polymerization processes. The structural and morphological characteristics of the synthesized material are systematically examined by X-ray diffraction, scanning electron microscopy, thermo-gravimetry, differential scanning calorimetry and infrared spectroscopy techniques. The adsorption property of the modified clay was evaluated for the removal of a reactive dye (methylene blue) from aqueous solution at room temperature (25 C) via batch adsorption. [less ▲]

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See detailApplication of isotopic tracers as a tool for understanding hydrodynamic behavior of the highly exploited Diass aquifer system (Senegal)
Madioune, Diakher Hélène; Faye, Serigne; Orban, Philippe ULg et al

in Journal of Hydrology (2014), 511

The Diass horst aquifer system located 50 km east of Dakar (Senegal) is exploited in two main aquifers covered by a sandy superficial aquifer: the confined/unconfined Palaeocene karstic limestone and the ... [more ▼]

The Diass horst aquifer system located 50 km east of Dakar (Senegal) is exploited in two main aquifers covered by a sandy superficial aquifer: the confined/unconfined Palaeocene karstic limestone and the confined Maastrichtian sandstone aquifer underneath. This system has experienced intensive groundwater abstraction during the last 50 years to supply increasing water demand, agricultural and industrial needs. The high abstraction rate from 1989 to 2009 (about 109,000 m3/d) has caused a continuous groundwater level decline (up to 30 m), a modification of the groundwater flow and salinization in parts of the aquifers. The objective of the study is to improve our understanding of the system functioning with regards to high pumping, identify the geochemical reactions that take place in the system, infer origin and timing of recharge by using mainly stable (δ18O, δ2H, 13C) and radioactive (3H and 14C) isotopes. Water types defined in the Piper diagram vary in order of abundance from Ca–HCO3 (65%), Ca/Na–Cl (20%), Na–HCO3 (3%) and Na–Cl (12%). Values of δ18O and δ2H for the superficial aquifer range between −5.8 and −4.2‰ and between −42 and −31‰, respectively. For the Palaeocene aquifer they range from −5.8 to −5.0‰ and from −38 to −31‰, respectively; values in the Maastrichtian aquifer are between −5.9 and −4.3‰ for δ18O and −38 to −26‰ for δ2H. Plotted against the conventional δ18O vs δ2H diagram, data from the upper aquifer exhibit a dispersed distribution with respect to isotopic fractionation while those of the Palaeocene and Maastrichtian aquifers are aligned parallel and slightly below/or on the Global Meteoric Water Line (GMWL) evidencing ancient waters which had evaporated during infiltration. The low tritium (generally <0.7 TU) and 14C (0.7–57.2 pmc) contents indicate predominance of older water being recharged during the Pleistocene and Holocene periods. However, few boreholes which exhibit high tritium (1.2–4.3 TU) and 14C (65.7–70.8 pmc) values indicate some mixture with recent water likely through faulting and vertical drainage from the upper to deeper aquifers as well as lateral flow along flow paths to the piezometric depressions created by pumping. [less ▲]

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See detailA multiple-level study of metal tolerance in Salix fragilis and Salix aurita clones
Evlard, Aricia ULg; Sergeant, Kjell; Printz, Bruno et al

in Journal of Proteomics (2014), 101C

The response of two willow clones (Salix fragilis (Sf) and S. aurita (Sa)) to the presence of metals (Zn, Cu, Cd, Ni) was studied. Rooted cuttings were planted in control and contaminated soil. After 100 ... [more ▼]

The response of two willow clones (Salix fragilis (Sf) and S. aurita (Sa)) to the presence of metals (Zn, Cu, Cd, Ni) was studied. Rooted cuttings were planted in control and contaminated soil. After 100 days, different parameters (biomass, chlorophyll fluorescence (Fv/Fm), pigment and sugar concentrations, electrolyte leakage and proteome-level changes) were analyzed. The growth of Sa was not influenced by metals whereas Sf produced significantly less biomass when exposed to the pollutants. Furthermore, although Sa did not show a growth reduction in the presence of metals, the overall view of the physiological results among others the changes in the accumulation of sugars and pigments indicated that metals had a more severe impact on this clone. The response at the proteome level confirmed these observations. The growth reduction and the proteomic changes in Sf indicate that this clone adjusts its metabolism to maintain cellular homeostasis. Sa on the contrary maintains growth but the physiological and proteomics data suggests that this can only be done at the cost of cellular deregulation. Therefore high biomass is not linked with a good tolerance strategy. In a long-term study the survival of Sa might be compromised making it a poorer candidate for phytoremediation efforts. [less ▲]

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See detailNest grouping patterns of bonobos (Pan paniscus) in relation to fruit availability in a forest-savannah mosaic
Serckx, Adeline ULg; Huynen, Marie-Claude ULg; Bastin, Jean-François ULg et al

in PLoS ONE (2014)

A topic of major interest in socio-ecology is the comparison of chimpanzees and bonobos’ grouping patterns. Numerous studies have highlighted the impact of social and environmental factors on the ... [more ▼]

A topic of major interest in socio-ecology is the comparison of chimpanzees and bonobos’ grouping patterns. Numerous studies have highlighted the impact of social and environmental factors on the different evolution in group cohesion seen in these sister species. We are still lacking, however, key information about bonobo social traits across their habitat range, in order to make accurate inter-species comparisons. In this study we investigated bonobo social cohesiveness at nesting sites depending on fruit availability in the forest-savannah mosaic of western Democratic Republic of Congo (DRC), a bonobo habitat which has received little attention from researchers and is characterized by high food resource variation within years. We collected data on two bonobo communities. Nest counts at nesting sites were used as a proxy for night grouping patterns and were analysed with regard to fruit availability. We also modelled bonobo population density at the site in order to investigate yearly variation. We found that one community density varied across the three years of surveys, suggesting that this bonobo community has significant variability in use of its home range. This finding highlights the importance of forest connectivity, a likely prerequisite for the ability of bonobos to adapt their ranging patterns to fruit availability changes. We found no influence of overall fruit availability on bonobo cohesiveness. Only fruit availability at the nesting sites showed a positive influence, indicating that bonobos favour food ‘hot spots’ as sleeping sites. Our findings have confirmed the results obtained from previous studies carried out in the dense tropical forests of DRC. Nevertheless, in order to clarify the impact of environmental variability on bonobo social cohesiveness, we will need to make direct observations of the apes in the forest-savannah mosaic as well as make comparisons across the entirety of the bonobos’ range using systematic methodology. [less ▲]

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See detailExploiting SNP Correlations within Random Forest for Genome-Wide Association Studies
Botta, Vincent ULg; Louppe, Gilles ULg; Geurts, Pierre ULg et al

in PLoS ONE (2014)

The primary goal of genome-wide association studies (GWAS) is to discover variants that could lead, in isolation or in combination, to a particular trait or disease. Standard approaches to GWAS, however ... [more ▼]

The primary goal of genome-wide association studies (GWAS) is to discover variants that could lead, in isolation or in combination, to a particular trait or disease. Standard approaches to GWAS, however, are usually based on univariate hypothesis tests and therefore can account neither for correlations due to linkage disequilibrium nor for combinations of several markers. To discover and leverage such potential multivariate interactions, we propose in this work an extension of the Random Forest algorithm tailored for structured GWAS data. In terms of risk prediction, we show empirically on several GWAS datasets that the proposed T-Trees method significantly outperforms both the original Random Forest algorithm and standard linear models, thereby suggesting the actual existence of multivariate non-linear effects due to the combinations of several SNPs. We also demonstrate that variable importances as derived from our method can help identify relevant loci. Finally, we highlight the strong impact that quality control procedures may have, both in terms of predictive power and loci identification. [less ▲]

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See detailSoil organic carbon assessment by field and airborne spectrometry in bare croplands: accounting for soil surface roughness
Denis, Antoine ULg; Stevens, Antoine; Van Wesemael, Bas et al

in Geoderma (2014), 226-227(August 2014), 94102

Visible, Near and Short Wave Infrared (VNSWIR) diffuse reflectance spectroscopy (350 nm to 2500 nm) has been proven to be an efficient tool to determine the Soil Organic Carbon (SOC) content. SOC ... [more ▼]

Visible, Near and Short Wave Infrared (VNSWIR) diffuse reflectance spectroscopy (350 nm to 2500 nm) has been proven to be an efficient tool to determine the Soil Organic Carbon (SOC) content. SOC assessment (SOCa) is usually done by using calibration samples and multivariate models. However one of the major constraints of this technique, when used in field conditions is the spatial variation in surface soil properties (soil water content, roughness, vegetation residue) which induces a spectral variability not directly related to SOC and hence reduces the SOCa accuracy. This study focuses on the impact of soil roughness on SOCa by outdoor VIS-NIR-SWIR spectroscopy and is based on the assumption that soil roughness effect can be approximated by its related shadowing effect. A new method for identifying and correcting the effect of soil shadow on reflectance spectra measured with an Analytical Spectral Devices (ASD) spectroradiometer and an Airborne Hyperspectral Sensor (AHS-160) on freshly tilled fields in the Grand Duchy of Luxembourg was elaborated and tested. This method is based on the shooting of soil vertical photographs in the visible spectrum and the derivation of a shadow correction factor resulting from the comparison of “reflectance” of shadowed and illuminated soil areas. Moreover, the study of laboratory ASD reflectance of shadowed soil samples showed that the influence of shadow on reflectance varies according to wavelength. Consequently a correction factor in the entire [350–2500 nm] spectral range was computed to translate this differential influence. Our results showed that SOCa was improved by 27% for field spectral data and by 25% for airborne spectral data by correcting the effect of soil relative shadow. However, compared to simple mathematical treatment of the spectra (first derivative, etc.) able to remove variation in soil albedo due to roughness, the proposed method, leads only to slightly more accurate SOCa. [less ▲]

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See detailEpoch-dependent absorption line profile variability in lambda Cep
Uuh-Sonda, J. M.; Rauw, Grégor ULg; Eenens, P. et al

in Revista Mexicana de Astronomia y Astrofisica (2014), 50

We present the analysis of a multi-epoch spectroscopic monitoring campaign of the O6 Ief star lambda Cep. Previous observations reported the existence of two modes of non-radial pulsations in this star ... [more ▼]

We present the analysis of a multi-epoch spectroscopic monitoring campaign of the O6 Ief star lambda Cep. Previous observations reported the existence of two modes of non-radial pulsations in this star. Our data reveal a much more complex situation. The frequency content of the power spectrum considerably changes from one epoch to the other. We find no stable frequency that can unambiguously be attributed to pulsations. The epoch-dependence of the frequencies and variability patterns are similar to what is seen in the wind emission lines of this and other Oef stars, suggesting that both phenomena likely have the same, currently still unknown, origin. [less ▲]

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See detailValidation analytique d'une méthode chromatographique destinée à rechercher et à identifier les opiacés naturels ou (semi) synthétiques
DUBOIS, Nathalie ULg; Counerotte, Stéphane ULg; Goffin, Eric ULg et al

in Annales de Biologie Clinique (2014), 72(2), 197-206

L’identification de la substance absorbée par un consommateur d’opiacés peut être problématique dans la mesure où il n’existe pas de biomarqueur spécifique pour toutes les molécules. Nous avons développé ... [more ▼]

L’identification de la substance absorbée par un consommateur d’opiacés peut être problématique dans la mesure où il n’existe pas de biomarqueur spécifique pour toutes les molécules. Nous avons développé une technique de chromatographie liquide ultra-haute pression couplée à un spectromètre de masse en tandem qui permet l’identification et le dosage de 25 opiacés dans le plasma. La préparation de l’échantillon consiste en une extraction en phase solide sur colonnes Oasis ® MCX (Waters). La méthode a été validée selon les critères préconisés par la FDA, complètement pour 21 substances et avec quelques réserves pour les 4 produits restants. Cette méthode a été appliquée à 80 patients traités au CHU de Liège pour lesquels la recherche d’opiacés était positive. L’identification du produit consommé a été effective dans 86 % des cas. [less ▲]

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See detailDo Consumers Pay More for What They Value More? The Case of Local Milk-based Dairy Products in Senegal
Lefevre, Mélanie ULg

in Agricultural and Resource Economics Review (2014), 43(1), 158-177

Senegalese consumers prefer milk-based dairy products that are local and fresh to ones produced with imported powder. However, prices for fresh-milk-based and powder-based products are not significantly ... [more ▼]

Senegalese consumers prefer milk-based dairy products that are local and fresh to ones produced with imported powder. However, prices for fresh-milk-based and powder-based products are not significantly different. I address this puzzle by first confirming the preference using choice-based conjoint data to evaluate whether Senegalese consumers will pay a significant positive premium for fresh local products. I then identify price determinants using a unique dataset of milk product characteristics. The results verify the Senegalese preference for fresh local dairy products and show that consumers’ misinformation regarding product composition prevents them from allocating a higher price to local milk-based products. [less ▲]

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See detailLa relation structure chimique-propriétés physiques des galactomannanes extraits de la caroube
Gillet, Sébastien ULg; Blecker, Christophe ULg; Paquot, Michel ULg et al

in Comptes Rendus Chimie (2014), 17(4),

Carob galactomannan fine chemical structure is closely related to the physical behavior developed in aqueous solution. Three elements of structural characterization are mainly described in the literature ... [more ▼]

Carob galactomannan fine chemical structure is closely related to the physical behavior developed in aqueous solution. Three elements of structural characterization are mainly described in the literature: the degree of galactose substitution, chain length, and galactose units distribution. This review article will attempt to highlight the impact of different structural features on physical properties such as solubility, viscosity, formation of hydrogels or gels in combination with other saccharides. The impact of industrial purification process on the structure and physical properties is also developed. [less ▲]

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See detailComparaison des populations de Culicoides Latreille 1809 (Diptera: Ceratopogonidae) d’une bergerie belge et d’une prairie ovine associée
Zimmer, Jean-Yves ULg; Losson, Bertrand ULg; Saegerman, Claude et al

in Annales de la Société Entomologique de France (2014)

Culicoides biting midges (Diptera: Ceratopogonidae) serve as biological vectors for several pathogens, including the Bluetongue virus and the recently described Schmallenberg virus in northern Europe ... [more ▼]

Culicoides biting midges (Diptera: Ceratopogonidae) serve as biological vectors for several pathogens, including the Bluetongue virus and the recently described Schmallenberg virus in northern Europe. These diseases have caused considerable direct and indirect economic losses to the sheep and cattle industries. This study undertaken between August and December 2007 on a sheep farm in the Namur province (Belgium) aims to evaluate Culicoides populations present inside a partially opened sheepfold and in a nearby sheep meadow, using light traps. The comparative analysis of insects trapped at 18 dates at regular intervals showed that Culicoides were most abundant inside this livestock building (17,450 midges) than in surrounding meadow (1,121 midges); this meadow had however a greater species diversity. The two species C. obsoletus and C. scoticus constituting the Obsoletus complex predominated for all trappings and females were much more numerous than males. Important capture of engorged females of the Obsoletus complex inside the sheepfold seems to reflect the possibility of an opportunistic endophagous behavior. Maintaining sheep inside livestock buildings in order to reduce the risk of Culicoides bites – and thus of pathogens transmission – however requires to limit biting midge populations which are likely to enter or to develop inside these buildings. Implementation of effective sanitation and hygiene measures against midges present inside farms, as well as establishing of measures to protect livestock against intrusion and improvement of “midge-proofing” of animal housing are therefore highly recommended. [less ▲]

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See detailExigences administratives et condition suspensive dans la vente immobilière
Kohl, Benoît ULg; Onclin, François ULg

in Revue Critique de Jurisprudence Belge [= RCJB] (2014), (1), 13-55

Cette étude est consacrée à l'utilisation de la condition suspensive en lien avec les exigences administratives, dans la matière spécifique de la vente immobilière. Le foisonnement des exigences de nature ... [more ▼]

Cette étude est consacrée à l'utilisation de la condition suspensive en lien avec les exigences administratives, dans la matière spécifique de la vente immobilière. Le foisonnement des exigences de nature urbanistique, environnementale et énergétique, en lien avec les biens immeubles, pousse les intervenants à la vente de biens immeubles - qu'il s'agisse de particuliers ou de professionnels - à recourir à la modalité de la condition suspensive. Se pose dès lors la question de la validité de cette pratique. Cette contribution suit en réalité un arrêt de la Cour de cassation du 24 février 2011 qui porte sur la conclusion de la vente d'une parcelle, issue de la division d'un bien, sous la condition suspensive de la délivrance d'un permis de lotir. L'étude se divise en deux parties. La première offre un rappel, bien nécessaire, du droit commun. Elle analyse donc les différentes composantes de la condition suspensive. La seconde étudie, de manière plus spécifique, la mise sous condition suspensive de différentes exigences administratives en lien avec la vente immobilière. L'arrêt de la Cour de cassation précité y est notamment commenté. [less ▲]

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See detailIncreasing meltwater discharge from the Nuuk region of the Greenland ice sheet and implications for mass balance (1960-2012)
Van As, D; Andersen, ML; Petersen, D et al

in Journal of Glaciology (2014), 60(220), 314-322

We assess the runoff and surface mass balance (SMB) of the Greenland ice sheet in the Nuuk region (southwest) using output of two regional climate models (RCMs) evaluated by observations. The region ... [more ▼]

We assess the runoff and surface mass balance (SMB) of the Greenland ice sheet in the Nuuk region (southwest) using output of two regional climate models (RCMs) evaluated by observations. The region encompasses six glaciers that drain into Godtha ̊bsfjord. RCM data (1960–2012) are resampled to a high spatial resolution to include the narrow (relative to the native grid spacing) glacier trunks in the ice mask. Comparing RCM gridded results with automatic weather station (AWS) point measurements reveals that locally models can underestimate ablation and overestimate accumulation by up to tens of per cent. However, comparison with lake discharge indicates that modelled regional runoff totals are more accurate. Model results show that melt and runoff in the Nuuk region have doubled over the past two decades. Regional SMB attained negative values in recent high-melt years. Taking into account frontal ablation of the marine-terminating glaciers, the region lost 10–20 km3 w.e. a–1 in 2010–12. If 2010 melting prevails during the remainder of this century, a low-end estimate of sea-level rise of 5 mm is expected by 2100 from this relatively small section (2.6%) of the ice sheet alone. [less ▲]

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See detailEnjeux autour des forêts congolaises
Vermeulen, Cédric ULg

in Cahiers africains (2014), 84

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See detailInvestigation of the death of calves after epileptiform seizures associated with metabolic disorders
Chevalier, Marine; Lebreton, Pascal; Garnier, Catherine et al

in Cattle Practice (2014), 22(1), 10-16

Death of calves after epileptiform seizures can be caused by metabolic disorders including hypomagnesaemia, although a range of other conditions may also be implicated and therefore also warrant ... [more ▼]

Death of calves after epileptiform seizures can be caused by metabolic disorders including hypomagnesaemia, although a range of other conditions may also be implicated and therefore also warrant investigation. Hypomagnesaemia is primarily observed in herds where calves are fed exclusively with either milk or milk substitute products. Hyperparathyroidism is associated with congestion and hypertrophy of the parathyroid gland and causes both hypercalcaemia and hypophosphataemia. However, its exact aetiology currently remains unclear. The purpose of this study was to explain epileptiform seizures in calves from a cattle herd presenting both deaths and decreased average daily gain (ADG). A Montbeliard herd with calves presenting epileptiform seizures from the age of five weeks was studied. The herd consisted of 39 cows and 46 calves. Tachycardia, nervousness and trampling, violent seizures of tetany lasting approximately 15 minutes were all observed, while opisthotonos was observed in 5 calves. Three of the latter calves died. The remaining calves presented a decreased ADG. Blood and urine biochemical assays were performed on 8 sick calves to determine the aetiology of the clinical signs. The assays revealed normo/hyper-calcaemia, hypophosphataemia and hypomagnesaemia, as well as hypocalciuria, hyperphosphaturia and hypomagnesuria. Deficiencies in iodine, iron and vitamins A, D3 and E were also reported in the herd. These calves could potentially be suffering from hyperparathyroidism. Hyperparathyroidism results in hypomagnesaemia, hypovitaminosis-A and, on occassion, hypercalcaemia and hypophosphataemia. This condition can lead to seizures, muscular problems, heart attacks and anorexia. The simultaneous occurrence of hypomagnesaemia, hyperparathyroidism and hypovitaminosis-A has been never described in related research literature. This is, therefore, in all likelihood a new metabolic disorder facing young cattle. Blood and urine biochemical assays are important tools for the detection of this pathological entity in calves. A dosage of parathyroid hormone (PTH) by the enzyme-linked immunosorbent assay (EIA) method using a kit suitable for cattle can be used to detect hyperparathyroidism. [less ▲]

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See detailGeometrical guidance and trapping transition of human sperm cells
Guidobaldi, Alejandro; Jeyaram, Yogesh; Berdakin, Ivan et al

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2014), 89

The guidance of human sperm cells under con finement in quasi 2D microchambers is investigated using a purely physical method to control their distribution. Transport property measurements and simulations ... [more ▼]

The guidance of human sperm cells under con finement in quasi 2D microchambers is investigated using a purely physical method to control their distribution. Transport property measurements and simulations are performed with diluted sperm populations, for which eff ects of geometrical guidance and concentration are studied in detail. In particular, a trapping transition at convex angular wall features is identi ed and analyzed. We also show that highly efficient microratchets can be fabricated by using curved asymmetric obstacles to take advantage of the spermatozoa specifi c swimming strategy. [less ▲]

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See detailAdding Value to Agricultural Products and Agrifood Byproducts by Highlighting Functional Ingredients
Besbes, Souhail; Besbes, Souhail; Attia, Hamadi et al

in Journal of Chemistry (2014), 2014(848231), 1-2

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See detailSur quelles connaissances se baser pour évaluer l’état de santé des populations de truite commune (Salmo trutta)?
Gouraud, Véronique; Baran, Philippe; Bardonnet, Agnès et al

in Hydroécologie appliquée (2014)

Le retour au premier plan de la notion de santé des écosystèmes met en évidence la préoccupation de la société à mettre en oeuvre des mesures pour la protection des milieux anthropisés. Les critères ... [more ▼]

Le retour au premier plan de la notion de santé des écosystèmes met en évidence la préoccupation de la société à mettre en oeuvre des mesures pour la protection des milieux anthropisés. Les critères d’évaluation de la santé des peuplements piscicoles mis en oeuvre sont rarement débattus au sein de la communauté scientifique. L’exercice proposé ici devait permettre d’avoir ce débat sur la truite commune (Salmo trutta), espèce phare des cours d’eau situés en tête de bassin, qui représentent la majorité du réseau hydrographique français. La démarche visait à recueillir la conception qu’avait un nombre restreint d’experts, sur le fonctionnement de ces populations et sur les critères d’évaluation de leur fonctionnement. Les paramètres clé régulant chaque stade de développement ont été identifiés et hiérarchisés. Unconsensus s’est dégagé sur le fait que, dans l’état actuel des connaissances, le diagnostic peut être établi sur la base de l’analyse des paramètres abiotiques essentiels pour la biologie et, plus difficilement, sur l’analyse des paramètres biotiques. Pour tous les stades de développement, les paramètres identifiés sont liés à l’habitat (qualité du substrat, conditions hydrauliques, température et qualité de l’eau), l’hydrologie et la connectivité. Des connaissances demandent d’être acquises pour définir des critères biologiques. Cela implique de renforcer la surveillance biologique à long terme et les actions de recherche pour caractériser la variabilité des paramètres biologiques et identifier les échelles spatio-temporelles pertinentes et les processus fonctionnels. [less ▲]

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See detailWhy do heroin users refuse to participate in a heroin-assisted treatment trial?
Demaret, Isabelle ULg; Litran, Géraldine; Magoga, Cécile et al

in Heroin Addiction and Related Clinical Problems (2014), Epub ahead of print

Background: Heroin-assisted treatment (HAT) can improve the condition of heroin addicts who are resistant to other treatments. However, in a new HAT trial in Belgium, fewer subjects than expected were ... [more ▼]

Background: Heroin-assisted treatment (HAT) can improve the condition of heroin addicts who are resistant to other treatments. However, in a new HAT trial in Belgium, fewer subjects than expected were included. Aim: Our research team explored the reasons given by heroin users in explaining why they did not want to participate. Methods: In 2011, during the trial recruitment, we interviewed heroin users (n=52) who never took the opportunity to meet the research team during the recruitment process preceding the trial. Results: Of those 52 heroin users, 25 were afraid of the limited length of the HAT and 11 feared becoming more dependent as a result of HAT. Conclusion: A trial that was planned to last for a limited length of time may have demotivated heroin users who could otherwise have benefited from this new programme. [less ▲]

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See detailCFD-based Compartment model for description of mixing in bioreactors
Delafosse, Angélique ULg; Calvo, Sébastien ULg; Collignon, Marie-Laure ULg et al

in Chemical Engineering Science (2014), 106

In most bioprocesses, it is fundamental to accurately predict the hydrodynamics behavior of bioreactors of different size and its interaction with the biological reaction. Computational Fluid Dynamics can ... [more ▼]

In most bioprocesses, it is fundamental to accurately predict the hydrodynamics behavior of bioreactors of different size and its interaction with the biological reaction. Computational Fluid Dynamics can provide detailed modeling about hydrodynamics and mixing. However, it is computationally intensive, especially when reactions are taken into account. Another way to predict hydrodynamics is the use of “Compartment” or “Network-of-zones” model which are much less demanding in computation time than CFD. However, compartments and fluxes between them are often defined by considering global quantities not representative of the flow complexity. To overcome the limitations of these two methods, a solution is to combine compartment modeling and CFD simulations. The aim of this study is to propose a compartment model where the flow rates between two adjacent compartments are easily computed from the velocity fields obtained by CFD. The mixing evolution predicted by the CFD-based compartment model have been then compared with mixing experiment results. Unlike a CFD mixing simulation and a classical compartment model, the CFD-based compartment model proposed in this work reproduces with a good accuracy the spatial distribution of concentrations during the mixing process and this, without any adjustable parameters. [less ▲]

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See detailSystematic optimization of subcritical and transcritical organic Rankine cycles (ORCs) constrained by technical parameters in multiple applications
Maraver, Daniel; Royo, Javier; Lemort, Vincent ULg et al

in Applied Energy (2014), 117

The present work is focused on the thermodynamic optimization of organic Rankine cycles (ORCs) for power generation and CHP from different average heat source profiles (waste heat recovery, thermal oil ... [more ▼]

The present work is focused on the thermodynamic optimization of organic Rankine cycles (ORCs) for power generation and CHP from different average heat source profiles (waste heat recovery, thermal oil for cogeneration and geothermal). The general goal is to provide optimization guidelines for a wide range of operating conditions, for subcritical and transcritical, regenerative and non-regenerative cycles. A parameter assessment of the main equipment in the cycle (expander, heat exchangers and feed pump) was also carried out. An optimization model of the ORC (available as an electronic annex) is proposed to predict the best cycle performance (subcritical or transcritical), in terms of its exergy efficiency, with different working fluids. The working fluids considered are those most commonly used in commercial ORC units (R134a, R245fa, Solkatherm, n-Pentane, Octamethyltrisiloxane and Toluene). The optimal working fluid and operating conditions from a purely thermodynamic approach are limited by the technological constraints of the expander, the heat exchangers and the feed pump. Hence, a complementary assessment of both approaches is more adequate to obtain some preliminary design guidelines for ORC units. [less ▲]

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See detailDetermination of the magnetic penetration depth in a superconducting Pb film
Brisbois, Jérémy ULg; Raes, Bart; Van de Vondel, Joris et al

in Journal of Applied Physics (2014), 115(10), 103906

By means of scanning Hall probe microscopy technique we accurately map the magnetic field pattern produced by Meissner screening currents in a thin superconducting Pb stripe. The obtained field profile ... [more ▼]

By means of scanning Hall probe microscopy technique we accurately map the magnetic field pattern produced by Meissner screening currents in a thin superconducting Pb stripe. The obtained field profile allows us to quantitatively estimate the Pearl length Λ without the need of pre-calibrating the Hall sensor. This fact contrasts with the information acquired through the spatial field dependence of an individual flux quantum where the scanning height and the magnetic penetration depth combine in a single inseparable parameter. The derived London penetration depth λL coincides with the values previously reported for bulk Pb once the kinetic suppression of the order parameter is properly taken into account. [less ▲]

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See detailDevelopment of a quantitative approach using surface-enhanced Raman chemical imaging: First step for the determination of an impurity in a pharmaceutical model
De Bleye, Charlotte ULg; Sacre, Pierre-Yves ULg; Dumont, Elodie ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2014), 90

This publication reports, for the first time, the development of a quantitative approach using surface-enhanced Raman chemical imaging (SER-CI). A pharmaceutical model presented as tablets based on ... [more ▼]

This publication reports, for the first time, the development of a quantitative approach using surface-enhanced Raman chemical imaging (SER-CI). A pharmaceutical model presented as tablets based on paracetamol, which is the most sold drug around the world, was used to develop this approach. 4-Aminophenol is the main impurity of paracetamol and is actively researched in pharmaceutical formulations because of its toxicity. As its concentration is generally very low (<0.1%, w/w), conventional Raman chemical imaging cannot be used. In this context, a SER-CI method was developed to quantify 4-aminophenol assessing a limit of quantification below its limit of specification of 1000 ppm. Citrate-reduced silver nanoparticles were used as SERS substrate and these nanoparticles were functionalized using 1-butanethiol. Different ways to cover the tablets surface by butanethiol-functionalized silver nanoparticles were tested and a homogeneity study of the silver nanoparticles covering was realized. This homogeneity study was performed in order to choose the best way to cover the surface of tablets by silver colloid. Afterwards, the optimization of the SER-CI approach was necessary and different spectral intensity normalizations were tested. Finally, a quantitative approach using SER-CI was developed enabling to quantify 4-aminophenol from 0.025% to 0.2% in paracetamol tablets. This quantitative approach was tested on two different series of tablets using different batches of silver nanoparticles. [less ▲]

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See detailSmall impact of surrounding oceanic conditions on 2007–2012 Greenland Ice Sheet surface mass balance
Noel, Brice; Fettweis, Xavier ULg; van de Berg, W.J. et al

in Cryosphere Discussions (The) (2014), 8

During recent summers (2007–2012), several surface melt records were broken over the Greenland Ice Sheet (GrIS). The extreme summer melt resulted in part from a persistent negative phase of the North ... [more ▼]

During recent summers (2007–2012), several surface melt records were broken over the Greenland Ice Sheet (GrIS). The extreme summer melt resulted in part from a persistent negative phase of the North-Atlantic Oscillation (NAO), favouring warmer than normal conditions over the GrIS. In addition, it has been suggested that significant anomalies in sea ice cover (SIC) and sea surface temperature (SST) may partially explain recent anomalous GrIS surface melt. To assess the impact of 2007–2012 SIC and SST anomalies on GrIS surface mass balance (SMB), a set of sensitivity experiments was carried out with the regional climate model MAR. These simulations suggest that changes in SST and SIC in the seas surrounding Greenland do not significantly impact GrIS SMB, due to the katabatic winds blocking effect. These winds are strong enough to prevent oceanic near-surface air, influenced by SIC and SST variability, from penetrating far inland. Therefore, the ice sheet SMB response is restricted to coastal regions, where katabatic winds are weaker. However, anomalies in SIC and SST could have indirectly affected the surface melt by changing the general circulation in the North Atlantic region, favouring more frequent warm air advection to the GrIS. [less ▲]

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See detailThe yellow hypergiant HR 5171 A: Resolving a massive interacting binary in the common envelope phase
Chesneau, O.; Meilland, A.; Chapellier, E. et al

in Astronomy and Astrophysics (2014), 563

Context. Only a few stars are caught in the very brief and often crucial stages when they quickly traverse the Hertzsprung-Russell diagram, and none has yet been spatially resolved in the mass transfer ... [more ▼]

Context. Only a few stars are caught in the very brief and often crucial stages when they quickly traverse the Hertzsprung-Russell diagram, and none has yet been spatially resolved in the mass transfer phase. Aims: We initiated long-term optical interferometry monitoring of the diameters of massive and unstable yellow hypergiants (YHG) with the goal of detecting both the long-term evolution of their radius and shorter term formation of a possible pseudo-photosphere related to proposed large mass-loss events. Methods: We observed HR 5171 A with AMBER/VLTI. We also examined archival photometric data in the visual and near-IR spanning more than 60 years, as well as sparse spectroscopic data. Results: HR 5171 Aexhibits a complex appearance. Our AMBER data reveal a surprisingly large star for a YHG R∗ = 1315 ± 260R⊙ (or ~6.1 AU) at the distance of 3.6 ± 0.5 kpc. The source is surrounded by an extended nebulosity, and these data also show a large level of asymmetry in the brightness distribution of the system, which we attribute to a newly discovered companion star located in front of the primary star. The companion's signature is also detected in the visual photometry, which indicates an orbital period of Porb = 1304 ± 6 d. Modeling the light curve with the NIGHTFALL program provides clear evidence that the system is a contact or possibly over-contact eclipsing binary. A total current system mass of 39^+40_-22 M⊙ and a high mass ratio q ≥ 10 is inferred for the system. Conclusions: The low-mass companion of HR 5171 is very close to the primary star that is embedded within its dense wind. Tight constraints on the inclination and vsini of the primary are lacking, which prevents us from determining its influence precisely on the mass-loss phenomenon, but the system is probably experiencing a wind Roche-Lobe overflow. Depending on the amount of angular momentum that can be transferred to the stellar envelope, HR 5171 A may become a fast-rotating B[e]/luminous blue variable/Wolf-Rayet star. In any case, HR 5171 A highlights the possible importance of binaries for interpreting the unstable YHGs and for massive star evolution in general. [less ▲]

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See detailImpacts of earthworms on soil components and dynamics. A review
Lemtiri, Aboulkacem ULg; Colinet, Gilles ULg; Alabi, Taofic ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18

Earthworm populations are important decomposers contributing to aggregate formation and nutrient cycling processes involving nitrogen cycles, phosphorus and carbon. They are known to influence soil ... [more ▼]

Earthworm populations are important decomposers contributing to aggregate formation and nutrient cycling processes involving nitrogen cycles, phosphorus and carbon. They are known to influence soil fertility by participating to important processes in soil such as soil structure regulation and organic matter dynamics. Earthworms also modify the microbial communities through digestion, stimulation and dispersion in casts. Consequently, changes in the activities of earthworm communities, as a result of soil management practices, can also be used as indicators of soil fertility and quality. It is therefore important to understand how earthworm communities affect soil dynamics. This review adresses the current state of knowledge on earthworm’s impacts on soil structure and soil organic matter (carbon, nitrogen, and phosphorus) dynamics, with special emphasis on the effects of land management practices on earthworm communities. [less ▲]

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See detailClimatological study of ionospheric irregularities over the European mid-latitude sector with GPS
Wautelet, Gilles ULg; Warnant, René ULg

in Journal of Geodesy (2014), 88(3), 223-240

High-frequency variability of the ionosphere, or irregularities, constitutes the main threat for real-time precise positioning techniques based on Global Navigation Satellite Systems (GNSS) measurements ... [more ▼]

High-frequency variability of the ionosphere, or irregularities, constitutes the main threat for real-time precise positioning techniques based on Global Navigation Satellite Systems (GNSS) measurements. Indeed, during periods of enhanced ionospheric variability, GNSS users in the field – who cannot verify the integrity of their measurements – will experience positioning errors that can reach several decimeters, while the nominal accuracy of the technique is cm-level. In the frame of this paper, a climatological analysis of irregularities over the European mid-latitude region is presented. Based on a ten year GPS dataset over Belgium, the work analyzes the occurrence rate (as a function of the solar cycle, season and local time) as well as the amplitude of ionospheric irregularities observed at a single GPS station. The study covers irregularities either due to space weather events (solar origin) or of terrestrial origin. If space weather irregularities are responsible for the largest effects in terms of ionospheric error, their occurrence rate highly depends on solar activity. Indeed, the occurrence rate of ionospheric irregularities is about 9% during solar maximum, whereas it drops to about 0% during medium or low solar activity periods. Medium-Scale Ionospheric Disturbances (MSTIDs) occurring during daytime in autumn/winter are the most recurrent pattern of the time series, with yearly proportions slightly varying with the solar cycle and an amplitude of about 10% of the TEC background. Another recurrent irregularity type, though less frequent than MSTIDs, is the noise-like variability in TEC observed during summer nighttime, under quiet geomagnetic conditions. These summer nighttime irregularities exhibit amplitudes ranging between 8 and 15% of the TEC background. [less ▲]

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See detailL'ÉCHO-DOPPLER TRANSCRÂNIEN DANS LA PRISE EN CHARE DES STÉNOSES ARTÉRIELLES CERVICALES ET INTRACRÂNIENNES
SCHOYSMAN, Laurent ULg; TSHIBANDA, Luaba ULg; OTTO, Bernard ULg et al

in Revue Médicale de Liège (2014), 69

Le progrès technique en imagerie a permis le développement de l’écho-Doppler transcrânien en mode duplex ou triplex. A côté des autres techniques de neuro-imagerie, son intérêt dans la pathologie ... [more ▼]

Le progrès technique en imagerie a permis le développement de l’écho-Doppler transcrânien en mode duplex ou triplex. A côté des autres techniques de neuro-imagerie, son intérêt dans la pathologie vasculaire cérébrale va grandissant. Le présent article a pour but de présenter cette technique en détaillant ses indications actuelles chez les patients présentant des sténoses artérielles cervicales et intra-crâniennes. [less ▲]

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See detailOptimized look-ahead tree policies: a bridge between look-ahead tree policies and direct policy search
Jung, Tobias ULg; Wehenkel, Louis ULg; Ernst, Damien ULg et al

in International Journal of Adaptive Control and Signal Processing (2014), 28(3-5), 255-289

Direct policy search (DPS) and look-ahead tree (LT) policies are two popular techniques for solving difficult sequential decision-making problems. They both are simple to implement, widely applicable ... [more ▼]

Direct policy search (DPS) and look-ahead tree (LT) policies are two popular techniques for solving difficult sequential decision-making problems. They both are simple to implement, widely applicable without making strong assumptions on the structure of the problem, and capable of producing high performance control policies. However, computationally both of them are, each in their own way, very expensive. DPS can require huge offline resources (effort required to obtain the policy) to first select an appropriate space of parameterized policies that works well for the targeted problem, and then to determine the best values of the parameters via global optimization. LT policies do not require any offline resources; however, they typically require huge online resources (effort required to calculate the best decision at each step) in order to grow trees of sufficient depth. In this paper, we propose optimized look-ahead trees (OLT), a model-based policy learning scheme that lies at the intersection of DPS and LT. In OLT, the control policy is represented indirectly through an algorithm that at each decision step develops, as in LT using a model of the dynamics, a small look-ahead tree until a prespecified online budget is exhausted. Unlike LT, the development of the tree is not driven by a generic heuristic; rather, the heuristic is optimized for the target problem and implemented as a parameterized node scoring function learned offline via DPS. We experimentally compare OLT with pure DPS and pure LT variants on optimal control benchmark domains. The results show that the LT-based representation is a versatile way of compactly representing policies in a DPS scheme (which results in OLT being easier to tune and having lower offline complexity than pure DPS); while at the same time, DPS helps to significantly reduce the size of the look-ahead trees that are required to take high-quality decisions (which results in OLT having lower online complexity than pure LT). Moreover, OLT produces overall better performing policies than pure DPS and pure LT and also results in policies that are robust with respect to perturbations of the initial conditions. [less ▲]

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See detailA differential Lyapunov framework for contraction analysis
Forni, Fulvio ULg; Sepulchre, Rodolphe ULg

in IEEE Transactions on Automatic Control (2014), 59(3), 614-628

Lyapunov's second theorem is an essential tool for stability analysis of differential equations. The paper provides an analog theorem for incremental stability analysis by lifting the Lyapunov function to ... [more ▼]

Lyapunov's second theorem is an essential tool for stability analysis of differential equations. The paper provides an analog theorem for incremental stability analysis by lifting the Lyapunov function to the tangent bundle. The Lyapunov function endows the state-space with a Finsler structure. Incremental stability is inferred from infinitesimal contraction of the Finsler metrics through integration along solutions curves. [less ▲]

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See detailMode identification based on time-series spectrophotometry for the bright rapid sdB pulsator EC 01541-1409
Randall, Suzanna K; Fontaine, Gilles; Geier, Stephan et al

in Astronomy and Astrophysics (2014), 563

We present an analysis of time-resolved spectrophotometry gathered with FORS/VLT for the rapidly pulsating hot B subdwarf EC 01541-1409 with the aim of identifying the degree index ℓ of the larger ... [more ▼]

We present an analysis of time-resolved spectrophotometry gathered with FORS/VLT for the rapidly pulsating hot B subdwarf EC 01541-1409 with the aim of identifying the degree index ℓ of the larger amplitude modes. This mode identification can be extremely useful in detailed searches for viable asteroseismic models in parameter space, and can be crucial for testing the validity of a solution a posteriori. To achieve it, we exploit the ℓ-dependence of the monochromatic amplitude, phase, and velocity-to-amplitude ratio of a mode as a function of wavelength. We use the ℓ-sensitive phase lag between the flux perturbation and the radial velocity as an additional diagnostic tool. On this basis, we are able to unambiguously identify the dominant 140.5 s pulsation of our target as a radial mode, and the second-highest amplitude periodicity at 145.8 s as an ℓ = 2 mode. We further exploit the exceptionally high-sensitivity data that we gathered for the dominant mode to infer modal properties that are usually quite difficult to estimate in sdB pulsators, namely the physical values of the dimensionless radius, temperature, and surface gravity perturbations. [less ▲]

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See detailRevue épidémiologique des blessures lors de la pratique du rugby à XV
Kaux, Jean-François ULg; Julia, Marc; Chupin, Marie et al

in Journal de Traumatologie du Sport (2014), 31(1), 49-53

Rugby is an increasingly popular sport. Full contact being a major characteristic of rugby, injuries are not uncommon. The incidence of injury in Rugby Union reaches 30–91 per 1,000 hours of game time ... [more ▼]

Rugby is an increasingly popular sport. Full contact being a major characteristic of rugby, injuries are not uncommon. The incidence of injury in Rugby Union reaches 30–91 per 1,000 hours of game time. This epidemiological review of injuries in rugby players reports their localization, nature, causes, moment of occurrence in matches and seasonal trends as well as the influence of the player’s position, field conditions, and duration of off time after injury. [less ▲]

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See detailAn astronomical survey conducted in Belgium
Nazé, Yaël ULg; Fontaine, Sébastien ULg

in Physics Education (2014), 49

This article presents the results of the first survey conducted in Belgium about the interest and knowledge in astronomy. Two samples were studied, the public at large (667 questionnaires) and students ... [more ▼]

This article presents the results of the first survey conducted in Belgium about the interest and knowledge in astronomy. Two samples were studied, the public at large (667 questionnaires) and students (2589 questionnaires), but the results are generally similar in both samples. We evaluated people’s interest, main information source, and attitudes towards astronomy, as well as their supposed and actual knowledge of the subject. The main conclusion is that, despite a poor self-confidence, people do know the basic astronomical concepts. However, that knowledge is not deeply rooted, as reasoning questions show well-spread misconceptions and/or misunderstandings. [less ▲]

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See detailTransiting planets from WASP-South, Euler and TRAPPIST: WASP-68 b, WASP-73 b and WASP-88 b, three hot Jupiters transiting evolved solar-type stars
Delrez, Laetitia ULg; Van Grootel, Valérie ULg; Anderson, D. R. et al

in Astronomy and Astrophysics (2014)

We report the discovery by the WASP transit survey of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. WASP-68 b has a mass of 0.95+-0.03 M_Jup, a radius of 1.24-0.06+0.10 R_Jup, and orbits a V ... [more ▼]

We report the discovery by the WASP transit survey of three new hot Jupiters, WASP-68 b, WASP-73 b and WASP-88 b. WASP-68 b has a mass of 0.95+-0.03 M_Jup, a radius of 1.24-0.06+0.10 R_Jup, and orbits a V=10.7 G0-type star (1.24+-0.03 M_sun, 1.69-0.06+0.11 R_sun, T_eff=5911+-60 K) with a period of 5.084298+-0.000015 days. Its size is typical of hot Jupiters with similar masses. WASP-73 b is significantly more massive (1.88-0.06+0.07 M_Jup) and slightly larger (1.16-0.08+0.12 R_Jup) than Jupiter. It orbits a V=10.5 F9-type star (1.34-0.04+0.05 M_sun, 2.07-0.08+0.19 R_sun, T_eff=6036+-120 K) every 4.08722+-0.00022 days. Despite its high irradiation (2.3 10^9 erg s^-1 cm^-2), WASP-73 b has a high mean density (1.20-0.30+0.26 \rho_Jup) that suggests an enrichment of the planet in heavy elements. WASP-88 b is a 0.56+-0.08 M_Jup planet orbiting a V=11.4 F6-type star (1.45+-0.05 M_sun, 2.08-0.06+0.12 R_sun, T_eff=6431+-130 K) with a period of 4.954000+-0.000019 days. With a radius of 1.70-0.07+0.13 R_Jup, it joins the handful of planets with super-inflated radii. The ranges of ages we determine through stellar evolution modeling are 4.5-7.0 Gyr for WASP-68, 2.8-5.7 Gyr for WASP-73 and 1.8-4.3 Gyr for WASP-88. WASP-73 appears to be a significantly evolved star, close to or already in the subgiant phase. WASP-68 and WASP-88 are less evolved, although in an advanced stage of core H-burning. [less ▲]

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See detailPourquoi tant de richesse? Dossier Reliques & reliquaires
George, Philippe ULg

in Arts Sacrés (2014), 28

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See detailMineralogical and geotechnical characterization of clays from Northern Morocco for their potential use in ceramic industry
El Ouahabi, Meriam ULg; Daoudi, Lahcen; Fagel, Nathalie ULg

in Clay Minerals (2014), 49

This study focuses on the mineralogical and geotechnical characterization of Northern Morocco clays (i.e., from Tangier and Tetouan areas) and further comparison with main clay ores used in national ... [more ▼]

This study focuses on the mineralogical and geotechnical characterization of Northern Morocco clays (i.e., from Tangier and Tetouan areas) and further comparison with main clay ores used in national ceramic (i.e., from Meknes, Fes, Salé and Safi regions). Sampled clays were analyzed by X-ray diffraction on bulk and clay (< 2 µm) fractions to identify the mineralogical assemblages of the clay outcrops. Further analyses were conducted to determine the particle size distribution (laser diffraction particle analyser), the total organic matter content (from LossOnIgnition measurements) and the Atterberg limits of the raw clays. The aims of this study were first to investigate the spatial variability of the clay samples and second to evaluate their potential application as raw materials in ceramic industry. Tetouan and Tangier clays are characterized by diversified mineralogical assemblages (in particular a variable proportion of clay, quartz and calcite) in regard with Meknes, Fes, Salé and Safi clays (high clay content, quartz and calcite). The clay fraction of Tetouan and Tangier samples is dominated by illite and kaolinite with variable contribution of chlorite, smectite and/or vermiculite. Illite is the dominant phase in Meknes, Fes, Safi and Salé clays, but is associated with kaolinite. There is no direct relationship between the mineral assemblage composition and the lithology of the series. The studied clays materials consist generally in fine particles with medium to high plasticity and low organic matter content. Taking into account mineralogy, grain-size distribution and plasticity those clays seem to be suitable as raw material for the growing Morocco ceramic industry. [less ▲]

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