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See detailEvaluation sommaire du dispositif de formation initiale à l'ULg et pistes d'amélioration.
Simons, Germain ULg

Conference (2012, August 31)

Dans cette communication, nous présentons d'abord le dispositif de formation initiale des enseignants du secondaire supérieur dans la Fédération Wallonie-Bruxelles. Ensuite, nous épinglons quelques points ... [more ▼]

Dans cette communication, nous présentons d'abord le dispositif de formation initiale des enseignants du secondaire supérieur dans la Fédération Wallonie-Bruxelles. Ensuite, nous épinglons quelques points forts et problèmes liés à cette formation. Enfin, nous proposons des pistes de solutions pour optimiser le dispositif actuel. [less ▲]

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See detailDevelopment and Identification of a Closed-Loop Model of the Cardiovascular System Including the Atria
Pironet, Antoine ULg; Revie, James A.; Paeme, Sabine ULg et al

Conference (2012, August 31)

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See detailExemple d'un dispositif de formation basé sur l'accompagnement réflexif de la pratique : le CAPAES en langues modernes à l'ULg
Simons, Germain ULg

Conference (2012, August 31)

Après avoir brièvement décrit le contexte général du CAPAES en FWB, nous présentons le dispositif de formation en didactique professionnelle des langues modernes à l'ULg, en nous concentrant ... [more ▼]

Après avoir brièvement décrit le contexte général du CAPAES en FWB, nous présentons le dispositif de formation en didactique professionnelle des langues modernes à l'ULg, en nous concentrant principalement sur l'accompagnement individualisé des étudiants-enseignants assisté par la vidéo (autoscopie). Nous fournissons ensuite quelques éléments d'évaluation de ce dispositif de formation basés sur nos observations et sur deux types d'enquêtes (questionnaires et entretiens semi-structurés). Enfin, sur la base de cette évaluation croisée, nous proposons quelques pistes pour optimiser le dispositif actuel. [less ▲]

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See detailSymmetries in the three-Higgs-doublet model
Ivanov, Igor ULg

Conference (2012, August 31)

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See detailThe role of distinctiveness in person recognition from faces and voices
Barsics, Catherine ULg; Brédart, Serge ULg

Conference (2012, August 30)

Objectives: When we recognize a familiar person, we can retrieve different kinds of information about her/him: semantic information (e.g. the person’s occupation), episodic information, such as a memory ... [more ▼]

Objectives: When we recognize a familiar person, we can retrieve different kinds of information about her/him: semantic information (e.g. the person’s occupation), episodic information, such as a memory of a specific occasion on which this person has previously been encountered and lexical information (i.e. the name). Recent findings indicated that semantic and episodic information retrieval is more likely to be elicited following familiar face than voice recognition. The present study was designed in order to explore the potential role of stimulus distinctiveness as an underlying factor of the face advantage. Design: The design included two within-subject factors: the stimulus domain (faces or voices) and the stimulus distinctiveness (distinctive or typical). Methods: The proportions of episodic and semantic information recalled following the recognition of famous faces and voices was assessed, using an adapted version of the Remember/Know paradigm. Results: In line with earlier results, more semantic and episodic information was retrieved from faces than voices. Moreover, semantic information was better retrieved from distinctive than typical stimuli. Nonetheless, distinctiveness impacted less than domain on the recall of semantic information, since more semantic details were retrieved from typical faces than from distinctive voices. Conclusions: These results are discussed in the light of current models of person recognition. [less ▲]

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See detailEstimation of genetic parameters for longitudinal measurements of feed intake in Piétrain sire lines
Dufrasne, Marie ULg; Jaspart, Véronique; Wavreille, José et al

Conference (2012, August 30)

The aim of this study was to estimate the genetic parameters for longitudinal measurements of feed intake (FI) in a crossbred population of pigs to develop a genetic evaluation model for the estimation of ... [more ▼]

The aim of this study was to estimate the genetic parameters for longitudinal measurements of feed intake (FI) in a crossbred population of pigs to develop a genetic evaluation model for the estimation of breeding values for FI of Piétrain boars. Data were collected on crossbred pigs in test station in the context of the genetic evaluation system of Piétrain boars in the Walloon Region of Belgium. Trait analyzed was daily FI (DFI). Because there were no facilities to record individual DFI in the Walloon test station, individual DFI were assumed to be the total pen FI divided by the number of pigs per pen. The edited dataset consisted of 3,902 measurements of DFI recorded on 1,975 crossbred pigs from 75 purebred Piétrain sires and 150 Landrace dams from the hyperprolific Landrace K+ line. A random regression animal model with fixed effects of sex and pen, and random effects of additive genetic, permanent environment and residual was developed in this study. Random additive genetic and permanent environment effects were modeled with linear splines with knots located at 75, 100, 175 and 210 d. The mean DFI was 1.979 kg/d with a SD of 0.479 kg/d. Estimated heritability for DFI increased with age from 0.02 at 75 d to 0.30 at 210 d. Estimated genetic correlation between age decreased when age interval increased. These preliminary results are consistent with literature. However, additional research are ongoing to test alternative random regression models that should be better than using splines for longitudinal performance of DFI. Furthermore, genetic relationship between DFI and other production traits, like growth and carcass traits, must be analyzed. [less ▲]

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See detailAccompaniment - a professional care?
Pirard, Florence ULg

Conference (2012, August 30)

In the European contexts where the structure of service supply is divided and where the initial trainings of professionals of childcare services are inaccurate (low levels, a focus on medical approach ... [more ▼]

In the European contexts where the structure of service supply is divided and where the initial trainings of professionals of childcare services are inaccurate (low levels, a focus on medical approach without adopting a more global psycho-educational view, etc.), several ways of professional developments could be considered as « professional care». The case of the Brussels-Wallonia Federation shows the importance of educational orientations for all services (for children between 0-12 years) thanks to curricula understood as tools of professionalization (rather than of standardization) (OCED, 2001, 2006, 2012). The case also illustrates the necessity to have a comprehensive set of coordinated actions of professional accompaniment for several years (Pirard, 2011; Pirard, Barbier, 2012). This accompaniment could be considered as a «professional care» that acknowledges the process of individual and collective competencies growing when certain conditions are guaranteed (Urban, al., 2011). [less ▲]

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See detailWhat does participation mean for children aged under 3?
Camus, Pascale ULg

Conference (2012, August 29)

Research has shown that quality provisions (0-6) can have a positive effect on children’s development (Unicef, 2008, Nesse, 2009, EACA, 2009). In 1992, Belgium has ratified the Convention on the rights of ... [more ▼]

Research has shown that quality provisions (0-6) can have a positive effect on children’s development (Unicef, 2008, Nesse, 2009, EACA, 2009). In 1992, Belgium has ratified the Convention on the rights of the Child that mentions each child has the right to express his opinion, to be heard in all matters that concern his life. More globally rights to take part, to “participate” have been recognized to every child since birth. But the obstacles to give a voice to children who are often considered as having any are numerous: the risk to consider them like an “object” of care is higher when the children are under 3. The workshop has proposed to explore and question the nature and the extent of participation for those children that are taken care in ECEC services (out of their families). What has been central was questioning participation of little ones, proposing an analysis of selected literature, discussions on how to sustain professionals to see children as actors in everyday life. [less ▲]

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See detailThermochemical conversion routes of lignocellulosic biomass
Gerbinet, Saïcha ULg; Léonard, Angélique ULg

Conference (2012, August 28)

The thermo-chemical route, especially the gasification process is considered. This process converts carbonaceous biomass into combustible gas (CO, H2, CO2, CH4 and impurities) called syngas and this ... [more ▼]

The thermo-chemical route, especially the gasification process is considered. This process converts carbonaceous biomass into combustible gas (CO, H2, CO2, CH4 and impurities) called syngas and this syngas can be converted into a large range of products. Production of four of these compounds is specifically investigated: ethylene, propylene, diesel and DME. Diesel can be produced via a Fischer-Tropsch process, whereas DME (dimethyl ether) can be obtained directly or from methanol which is obtained from syngas. DME and diesel can serve as fuels in traditional motors. Syngas can also be used to produce ethylene and propylene, two building blocks for the chemical industry. An important bibliography study has been done to understand these processes in order to evaluate their environmental impacts. The Life Cycle Assessment (LCA) methodology will be used in this regard. A bibliography study on the LCA articles published in this filled has been performed and it appears that few studies have yet focused on the environmental impacts of the gasification process and production of biofuels. Most of the time, they do not use the LCA methodology or they do not take into account land use change impact and are only “well-to-tank” studies. Moreover, it seems that the production of building blocks for the chemical industry has never been investigated. During the next stages of this work, the best conversion routes of lignocellulosic biomass, in an environmental sense, will be determined. Gasification will also be compared with the fossil sector and the results will be checked by sensitivity and uncertainty analyses. The economic aspect will also be taken into account, for the better process, in an environmental view. So, the results of the full study will be a decision making tool for the industries involved in biomass valorisation and for governments. [less ▲]

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See detailAlternative single-step type genomic prediction equations
Gengler, Nicolas ULg; Nieuwhof, G.J.; Konstantinov, K.V. et al

Conference (2012, August 28)

Current derivations of single-step equations are based on modified relationships among animals replacing for genotyped animals and on an inverted scale, pedigree based relationships, by modified ones ... [more ▼]

Current derivations of single-step equations are based on modified relationships among animals replacing for genotyped animals and on an inverted scale, pedigree based relationships, by modified ones. These relationships are obtained as linear combination of strictly genomic and pedigree based relationships, therefore implicitly 'weighting' SNP and polygenic effects. Alternative equations were recently proposed de-absorbing the genomic relationships out of the equations. This derivation did not change basic assumptions, but was derived using a matrix of relationship differences. This presentation will show a new and alternative derivation of single-step type genomic prediction equations allowing joint estimation of GEBV and SNP effects based on the partitioning of genetic (co)variances. The method was derived from a random mixed inheritance model where SNP and residual polygenic effects are jointly modeled. The derived equations were modified to allow non-genotyped animals and to estimate directly and jointly GEBV and SNP effects. Equations resemble superficially recently proposed alternative single-step equations but were derived differently and are based on completely different assumptions. They also avoid certain issues in de-absorbing derivation linked to the matrix of relationship differences by using (co)variances. Several other advantages of the new equations are that weighting of SNP and polygenic effects becomes explicitly and that SNP effects are also estimated. This method makes better use of High-Density SNP panels and can be easily modified to accommodate other genetic effects as major gene effects or copy-number variant based effects. Finally these alternative equations combine advantages of single-step and of explicit SNP effect estimation based methods. Additional research is required to test and validate further the proposed method. [less ▲]

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See detailInteraction between the antifungal lipopeptide fengycin and lipid membrane
Deleu, Magali ULg; Nylander, Tommy

Conference (2012, August 28)

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See detailNaar de film? Ja, maar in het Nederlands of in het Vlaams?
Perrez, Julien ULg; Neven, Anneke

Conference (2012, August 28)

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See detailGenetic variance in environmental sensitivity for milk and milk quality in Walloon Holstein cattle
Vandenplas, Jérémie ULg; Bastin, Catherine ULg; Gengler, Nicolas ULg et al

Conference (2012, August 27)

Animals that are robust to environmental changes are desirable in the current dairy industry. This difference in environmental sensitivity can be studied through the heterogeneity of residual variance ... [more ▼]

Animals that are robust to environmental changes are desirable in the current dairy industry. This difference in environmental sensitivity can be studied through the heterogeneity of residual variance while homogeneous residual variance between animals is usually assumed homogeneous in traditional genetic evaluations. The aim of this study was to study genetic heterogeneity of residual variance by the estimation of variance components in residual variance for 5 milk and milk quality traits. 146,027 test-day records from 26,887 Walloon Holstein first-parity cows in 747 herds were available. All cows had at least 3 records and had a known sire. These sires had at least 10 cows with records and each herd x test-day had at least 5 cows. Five traits, milk yield, somatic cell score, and content in milk (g/dL) of oleic acid (C18:1 cis-9), monounsaturated and unsaturated fatty acids, were analyzed separately. Estimation of variance components was performed by running iteratively Expectation Maximization-Restricted Maximum Likelihood algorithm by the implementation of double hierarchical generalized linear models. For all traits, the genetic standard deviation in residual variance (i.e. approximately the genetic coefficient of variation of residual variance) was low and ranged between 0.12 and 0.17. The standard deviations due to herd x test day and permanent environment in residual variance ranged between 0.35 and 0.44 for herd x test-day effect and between 0.55 and 0.96 for permanent environmental effect. This study shows the heterogeneity of residual variance and the existence of some genetic variance in environmental sensitivity for all studied traits in the Walloon Holstein dairy cattle. [less ▲]

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See detailChoosing an aphid partner: a matter of taste and smell
Detrain, Claire; Fischer, Christophe ULg; Lognay, Georges ULg et al

Conference (2012, August 27)

Honeydew is the keystone upon which ants and aphids build their mutualistic relationship. We have investigated how sugar and volatile compounds from honeydew are involved in the discovery, the recognition ... [more ▼]

Honeydew is the keystone upon which ants and aphids build their mutualistic relationship. We have investigated how sugar and volatile compounds from honeydew are involved in the discovery, the recognition and the exploitation of aphid colonies by the black garden ant Lasius niger. In addition to semiochemicals produced by aphids, honeydew volatile compounds are used by ant scouts to orient themselves and distantly recognize myrmecophilous species. Once discovered, aphid colonies producing sugars which are the most beneficial to the ants are preferentially tended. In this respect, the ways each sugar acts upon the feeding behavior of ant foragers and triggers the laying of a recruitment trail are essential to understand how their collective exploitation of aphid colonies proceeds and why mutualistic interactions between ants and aphids are maintained. Sensitivity of ant scouts to honeydew sugars was also investigated. Dose-response curves revealed between-sugar differences with foragers being very sensitive even to small amounts of melezitose, a sugar specifically produced by aphid colonies. We discuss about the relevance of honeydew cues used by ants in the selection of sugary resources, the recognition of their honeydew-producing partners as well as in the assessment of size and nutritive value of exploited aphid colonies. [less ▲]

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See detailMid-infrared prediction of milk titratable acidity and its genetic variability in first-parity cows
Colinet, Frédéric ULg; Vanlierde, Amélie ULg; Vanden Bossche, sandrine ULg et al

Conference (2012, August 27)

Coagulation of milkhas a direct effect on cheese yield. Among several parameters, titratable acidity of milk (TA) influences all the phases of milk coagulation. In order to study the genetic variability ... [more ▼]

Coagulation of milkhas a direct effect on cheese yield. Among several parameters, titratable acidity of milk (TA) influences all the phases of milk coagulation. In order to study the genetic variability of this trait on a large scale, mid-infrared (MIR) chemometric methods were used to predict TA. A total of 507 milk samples collected in the Walloon Region of Belgium from individual cows were analyzed using a MIR spectrometer. TA was recorded as Dornic degree. An equation to predict TA from milk MIR spectrum was developed using partial least squared regression after a first derivative pre-treatment applied to the spectra to correct the baseline drift. During the calibration process, 45 outliers were detected and removed from the calibration set. The TA mean of the final calibration set was 16.62 (standard deviation (SD) = 1.80). The coefficient of determination (R²) was 0.82 for the calibration with a standard error (SE) of 0.76. A cross-validation (cv) was performed (R²cv = 0.81 with SEcv = 0.80). This equation was then applied on the spectral database generated during the Walloon routine milk recording. The variances components were estimated by REML using single-trait random regression animal test-day model. The dataset used included 33,717 records from 9,191 Holstein first-parity cows; the TA mean was 17.05 (SD = 1.35) and TA ranged from 12.83 to 20.87. Estimated daily heritabilities ranged from 0.43 at 5th day in milk to 0.59 at 215th day in milk indicating potential of selection. Further research will study phenotypic and genetic correlations between TA and milk production traits. [less ▲]

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See detailGenetics of the mineral contents in bovine milk predicted by mid-infrared spectrometry
Soyeurt, Hélène ULg; Dehareng, Frédéric; Romnée, Jean-Michel et al

Conference (2012, August 27)

Knowing the contents of minerals in milk like Ca or Na could be interesting to improve the nutritional quality of milk and to assess the animal health status. This study had two aims: 1) development of ... [more ▼]

Knowing the contents of minerals in milk like Ca or Na could be interesting to improve the nutritional quality of milk and to assess the animal health status. This study had two aims: 1) development of mid-infrared equations for mineral contents in milk by using an approach combining multiple countries, breeds, and production systems and 2) study of the genetic variability of these traits in the Walloon Holstein dairy cattle. Samples included in the calibration set were collected in Belgium, Luxembourg and France over 5 years. The calibration set included at least 400 samples analyzed by coupled plasma atomic emission spectrometry to quantify the contents of Na, Ca, Mg, P and K. The calibration coefficient of determination ranged between 0.69 for K and 0.93 for Na. The standard error of cross-validation was 63.35, 49.24, 64.33, 7.04, and 93.22 mg/kg of milk for Na, Ca, P, Mg and K. From these results, the quantification of milk minerals by mid-infrared is feasible. These equations were applied to more than 140,000 spectral records collected from 43,797 first parity Holstein cows in 1,233 herds. The variance components were estimated using Gibbs Sampling using single trait random regression models derived from the one used for the Walloon genetic evaluation of milk production traits. First results gave a daily heritability of 0.26 for Na, 0.45 for Ca, 0.48 for P, 0.46 for Mg, and 0.41 for K. Moderate negative genetic correlations were found between Na and the other studied traits. The highest correlation (0.69) was observed between P and Mg. These results confirmed the genetic variability of these traits. Further studies will be conducted to study the relationship between these traits and other traits (e.g., production, health). [less ▲]

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See detailLe nom et l’usage des lieux de l’habitation à Liège au XVIIIe siècle
Gilles, Isabelle ULg

Conference (2012, August 25)

L’histoire de l’architecture est aussi une histoire des mots. Pour peu que l’on s’y intéresse, le vocabulaire attribué à l’habitation, d’usage courant dans un espace temps donné, et le choix même des ... [more ▼]

L’histoire de l’architecture est aussi une histoire des mots. Pour peu que l’on s’y intéresse, le vocabulaire attribué à l’habitation, d’usage courant dans un espace temps donné, et le choix même des termes employés laissent transparaître une réalité historique parfois surprenante, souvent méconnue, toujours précieuse pour l’historien. Une étude menée sur le terrain liégeois du XVIIIe siècle, à travers des documents variés, manuscrits ou imprimés, textuels ou iconographiques, ajoute ainsi des saveurs à l’architecture qui s’y édifie. Le nom même donné à l’habitation peut déjà révéler toute sa consistance sociale. Ensuite, le terme attribué à chaque espace de l’habitation témoigne tantôt d’influences, le plus souvent françaises, tantôt de particularités locales ; particularités du langage et particularités des usages. Les sources permettent souvent de comprendre ces usages dévolus aux lieux qui se cachent derrière les mots, et partant de voir poindre une hiérarchie dans les maisons liégeoises. Certaines pièces semblent en effet réservées à des types précis de demeures, y assurent parfois des fonctions plus pointues. Enfin, si l’on place les textes sur une échelle chronologique, on observe que certains mots apparaissent, que d’autres s’effacent, que d’autres encore se métamorphosent ; autant de modifications du langage qui, si elles correspondent parfois à des changements dans les lieux de vie, reflètent toujours une transformation plus générale de la société de l’Ancien Régime. [less ▲]

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See detailAmélioration des performances génétiques des races tropicales par les races wallonnes.
Leroy, Pascal ULg; Moula, Nassim ULg; Huart, Alain et al

Conference (2012, August 25)

As part of the genetic improvement of production, selection of breeds (purebred selection) on the one hand and crossbreeding, exploiting the complementarity between breeds and hybrid vigor or heterosis ... [more ▼]

As part of the genetic improvement of production, selection of breeds (purebred selection) on the one hand and crossbreeding, exploiting the complementarity between breeds and hybrid vigor or heterosis other hand, are methods choice used by animal husbandry. The pure breeding as practiced in the developed world, based on the individual performance of breeding as well as the placement of the offspring, uses expensive infrastructure and significant human resources. In addition, genetic progress is slow and must be sustained effort. For all these reasons, in the less favored regions of the world, although the intra-breed selection is operational, most stakeholders are most often uses the crossbreeding technique leading to immediate results and protecting local breeds. Thus, in dairy cattle, many countries have used the Holstein, Brown in the Alps, and the Montbéliarde Normande with varying success. In the meat sector, in cattle, swine and sheep, as well as in the area of ​​poultry meat, crossing indigenous breeds with exotic breeds imported leads to interesting results. In the Walloon Region, due to the hard work of breeders, animals have emerged exceptional and, in cattle, swine and sheep, they are in fact, more muscular animals in the world. Thus, bulls Belgian Blue reared under natural conditions, have average daily gains as high as 2000 g / d with yields close to slaughter 70% Pietrain pigs reach values ​​of the performance slaughter of around 83% and the yield values ​​as high as 59% were observed in Texel sheep. All these animals have the characteristic of being very efficient while presenting carcasses with more muscle, less fat and less bone. As for local poultry type Ardennaise, it has remarkable phenotypes leading to immediate traceability (black members), more than 150 eggs per clutch and a darker meat.The author gives in detail examples of the use of crossbreeding with cattle, sheep, pig and poultry all originated from the Walloon Region of Belgium. [less ▲]

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See detailBrain-derived estrogens rapidly control sexual behavior in Japanese quail
Cornil, Charlotte ULg

Conference (2012, August 25)

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See detailLa résistance de Liège en août 14 et la reconnaissance française : histoire, mythe et mémoire
Bechet, Christophe ULg

Conference (2012, August 24)

Il n’est pas exagéré de dire que la décision belge de refuser l’ultimatum allemand du 2 août et la résistance consécutive de la position de Liège furent pour la France une « divine surprise ». Les ... [more ▼]

Il n’est pas exagéré de dire que la décision belge de refuser l’ultimatum allemand du 2 août et la résistance consécutive de la position de Liège furent pour la France une « divine surprise ». Les rapports de l’ambassade française à Bruxelles au cours des mois et même des années précédentes n’avaient en effet guère préparé le Quai d’Orsay au respect par le Gouvernement belge d’une stricte neutralité en cas de conflit. L’impact dans l’opinion publique française fut considérable au point que dès le 7 août 1914, la Ville de Liège se voit remettre la plus haute distinction de la République : La Légion d’Honneur. Décoration méritée car résistance il y a bien eu… Néanmoins, autour de cet événement qui aurait pu comme beaucoup d’autres histoires militaires tomber après quelques années dans les oubliettes de l’Histoire, sont venues se greffer rapidement de nombreuses implications historiographiques, politiques et culturelles. Sur le plan historiographique, il fut de bon ton de magnifier cette résistance à l’excès jusqu’à déclarer que la résistance de Liège avait permis à l’armée française de gagner du temps pour réaliser la manœuvre salvatrice de la Marne : la Ville de Liège connue pour sa francophilie séculaire avait donc permis à elle seule de sauver la République d’un désastre militaire ! Cette version de l’histoire bataille fut enseignée à des générations d’écoliers et jusqu’à l’Ecole de guerre à Bruxelles. Sur le plan politique, les cérémonies de commémoration magnifiant la résistance liégeoise constituent des occasions récurrentes de rapprochement franco-belge saluées d’ailleurs par les militants wallons et francophiles. [less ▲]

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See detailLe débat sur la véritable nature du corail
Vandersmissen, Jan ULg

Conference (2012, August 24)

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See detailUne bibliothèque modèle à l’Université de Liège? : le projet De Laet
Oger, Cécile ULg; Simon, Stéphanie ULg

Conference (2012, August 24)

Durant les années 1930, la situation des bâtiments occupés par la bibliothèque de l’Université de Liège s’avère particulièrement préoccupante. Devant la menace imminente de l’effondrement d’une partie de ... [more ▼]

Durant les années 1930, la situation des bâtiments occupés par la bibliothèque de l’Université de Liège s’avère particulièrement préoccupante. Devant la menace imminente de l’effondrement d’une partie de la bibliothèque, les autorités universitaires décident la construction d’une nouvelle bibliothèque, plus adaptée aux besoins de l’époque. Le projet est confié à l’architecte Armand De Laet. Celui-ci proposera au cours des années suivantes plusieurs versions d’un bâtiment imposant, en collaboration avec le bibliothécaire en chef de l’époque. Les hostilités du second conflit mondial empêcheront néanmoins à ce projet de voir le jour. Mis de côté au début de la guerre, ce projet sera définitivement abandonné en 1945. L’heure n’est désormais plus tant à l’esthétique et au grandiose qu’au pragmatisme et à la fonctionnalité des lieux. Les documents redécouverts récemment dans les archives de la bibliothèque permettent de retracer la conception et l’évolution de ce projet de grande envergure qui s’inscrit dans la lignée de ceux qui seront réalisés à la bibliothèque de l’Université de Gand et à la Bibliothèque Royale. [less ▲]

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See detailYvon Falise, architecte moderniste
Charlier, Sébastien ULg

Conference (2012, August 24)

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See detailL’impact des modèles de Lambert Lombard et de son entourage sur la sculpture sur pierre à Liège au XVIe siècle
Warnauts, Samuelle ULg

Conference (2012, August 23)

La montée d’un courant esthétique italianisant à Liège, au XVIe siècle, est bien perceptible dans l’art de la sculpture sur pierre, et plus particulièrement dans la production des reliefs dits en marbre ... [more ▼]

La montée d’un courant esthétique italianisant à Liège, au XVIe siècle, est bien perceptible dans l’art de la sculpture sur pierre, et plus particulièrement dans la production des reliefs dits en marbre noir de Theux. L’installation, dans la cité épiscopale, d’un sculpteur d’origine italienne, Nicolas Palardin, a sans doute eu un effet catalyseur, mais l’apport de cet artiste demeure difficile à cerner précisément, parce qu’aucune œuvre ne peut lui être attribuée avec certitude. En revanche, une étude attentive et systématique des reliefs conservés permet de mesurer l’empreinte profonde de la figure dominante de la Renaissance liégeoise, Lambert Lombard, et de son entourage. Nous proposerons des rapprochements inédits, jetant sur la question un éclairage nouveau. De manière plus large, nous présenterons une synthèse critique des données relatives à la production dite en marbre noir de Theux. [less ▲]

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See detailLes collections d'objets et d'oeuvres d'art de Louise de Savoie
Fagnart, Laure ULg

Conference (2012, August 23)

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See detailLes Éduens et César. Réflexions préliminaires
Dignef, Anthony ULg

Conference (2012, August 23)

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See detailLa tenture de l'Histoire d'Hercule des Musées royaux d'Art et d'Histoire de Bruxelles
Laruelle, Anne-Sophie ULg

Conference (2012, August 23)

Les Musées royaux d’Art et d’Histoire conservent quatre tapisseries du XVIe siècle qui formaient autrefois une tenture des Travaux d’Hercule. Ces pièces illustrent différents exploits du héros grec : ses ... [more ▼]

Les Musées royaux d’Art et d’Histoire conservent quatre tapisseries du XVIe siècle qui formaient autrefois une tenture des Travaux d’Hercule. Ces pièces illustrent différents exploits du héros grec : ses combats face à Cacus, Antée, Diomède et sa lutte contre les Centaures qui avaient capturé Hippodamie. Le thème des Travaux d’Hercule était fortement apprécié dans l’art de la tapisserie flamande du XVe au XVIIe siècle. Les quatre pièces de Bruxelles ont fait l’objet de multiples recherches portant sur l’iconographie, les bordures, l’atelier de production et les compositions. [less ▲]

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See detailNovas tecnologias e Resiliência
Nyssen, Anne-Sophie ULg

Conference (2012, August 22)

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See detailLe problème de Prouhet
Rigo, Michel ULg

Conference (2012, August 22)

Si on pense aux nombres, à leur théorie et à l'arithmétique, on fait rapidement face à de nombreuses questions simples à énoncer (elles ne font intervenir que des sommes, des produits ou des puissances de ... [more ▼]

Si on pense aux nombres, à leur théorie et à l'arithmétique, on fait rapidement face à de nombreuses questions simples à énoncer (elles ne font intervenir que des sommes, des produits ou des puissances de nombres entiers) mais leurs éventuelles solutions peuvent s'avérer redoutables. Dans cet exposé, on s'intéressera à un problème accessible dû à Prouhet (1851) : "partitionner l'ensemble {0,1,2,...,2^N-1} en deux sous-ensembles A et B de même taille de telle sorte que les sommes des éléments de A et B soient égales, les sommes des carrés des éléments de A et B soient égales, ..., les sommes des puissances (N-1)-ièmes des éléments de A et B soient égales ". Par exemple, pour N=3, on trouve 0+3+5+6=1+2+4+7 et 0^2+3^2+5^2+6^2=1^2+2^2+4^2+7^2. On en présentera une solution reposant de façon élégante sur les écritures en base 2 et on s'autorisera quelques digressions : produit de sinus, répétition et chevauchement, jeu d'échecs, généralisations, pavages colorés, composition musicale, tours de Hanoï, cubes magiques, ... Cet exposé est construit pour être une balade arithmétique amusante et inattendue, pouvant montrer à des élèves ouverts, un peu comme le prétend André DELEDICQ, que les mathématiques peuvent être jubilatoires. [less ▲]

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See detailVertical stratification and functional guilds in the bacterial community of Lake Kivu (East Africa)
Garcia-Armisen, T; Inceoglu, O; Llirós, M et al

Conference (2012, August 19)

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See detailUsing hurdle models to create maps of prey densities in southeastern of Norway
Bouyer, Yaëlle ULg; Rigot, Thibaud; Panzacchi, Manuela et al

Conference (2012, August 15)

Knowing prey distribution and density in areas where carnivores are present is an important condition to have a better understanding of carnivore movements (Karanth et al. 2004 ; Herfindal et al. 2005 ... [more ▼]

Knowing prey distribution and density in areas where carnivores are present is an important condition to have a better understanding of carnivore movements (Karanth et al. 2004 ; Herfindal et al. 2005). Southeastern of Norway has recently been recolonized by the European Lynx (Lynx lynx) and the wolf (Canis lupus) and in order to be able to predict these carnivore movements, it is important to produce detailed models of their prey abundance and habitat use. Roe deer (Capreolus capreolus), red deer (Cervus elaphus), moose (Alces alces) and mountain hare (Lepus timidus) are commonly hunted by lynx and wolf in Norway (Odden et al. 2006, Wikenros 2001, Müller 2006) but even if these species are well present in the southeastern, no distribution maps are available yet. Using hurdle models, we create the prey maps and test the extent of predictive modeling. Finally, we discuss the limits existing when trying to develop and use predictive maps at large scale. [less ▲]

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See detailRanging behaviour and sleeping sites of Macaca fascicularis in Bali Barat National Park, Indonesia
Brotcorne, Fany ULg; Maslarov, Cindy; Dosogne, Thibaut et al

Conference (2012, August 15)

Ranging behaviour and sleeping site selection are important primate behavioural traits likely to vary under environmental changes. We tested the role of ecological (predation avoidance) and anthropic ... [more ▼]

Ranging behaviour and sleeping site selection are important primate behavioural traits likely to vary under environmental changes. We tested the role of ecological (predation avoidance) and anthropic (human proximity) factors in Macaca fascicularis range use, an edge species known to prefer living along forests borders and in the vicinity of human settlements. Data result from 56 day follows of one group of Macaca fascicularis exploiting a human-modified landscape within Bali Barat National Park (Indonesia). Observations allowed identifying and describing 17 sleeping sites and the characteristics of 37 sleeping trees. Despite a large forest area available, the group’s home range centred around human settlements. The home range size, average daily range and daily travel decreased over the study period, while the human presence inside the park increased over the corresponding months. The proximity with humans also influenced the pattern of sleeping sites use; macaques slept more than expected close to human settlements and this tendency increased over the study period. In contradiction with the predation avoidance assumption, macaques did not choose sleeping trees significantly taller and larger than other trees available. We conclude that the observed sleeping site strategy (sleeping near humans) could be advantageous in terms of predator avoidance and proximity with human food, but additional influences should not be neglected. [less ▲]

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See detailA framework and approaches to develop an in-house CAT with freeware and open sources
Kimura, Tetsuo; Han, Kyung; Kosinski, Michal et al

Conference (2012, August 13)

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See detailRecepción actual de los manuscritos de Ferdinand de Saussure. Perspectivas teóricas e históricas.
Sofia, Estanislao ULg

Conference (2012, August 01)

Se le ha atribuido a Ferdinand de Saussure (1857-1913), a lo largo del siglo XX, la responsabilidad de más de una “revolución” [sobre la de los anagramas, ver Prosdocimi1894, p. 233]. Célebre en su época ... [more ▼]

Se le ha atribuido a Ferdinand de Saussure (1857-1913), a lo largo del siglo XX, la responsabilidad de más de una “revolución” [sobre la de los anagramas, ver Prosdocimi1894, p. 233]. Célebre en su época gracias a sus trabajos sobre el vocalismo indo-europeo (Saussure, 1879), cuyo estudio, precisamente, habría contribuido a revolucionar (Béguelin, 2003), Saussure alcanzó una difusión masiva póstumamente. El Cours de linguistique générale (1916) es así considerado por la tradición como el punto de inflexión que revolucionó (una vez más) las ciencias del lenguaje, al asumir y/o permitir un cambio de enfoque radical: el objeto de la lingüística sería no ya (o no ya solamente) la historia y la evolución de las lenguas, sino también (y sobre todo) la lengua en tanto sistema autónomo de signos (Saussure, 1916) cuya función esencial es la comunicación. Acentuando la importancia de este gesto, se erigió a Saussure en “fundador” no solamente de una escuela – el estructuralismo europeo – sino también, y más generalmente, de la lingüística moderna (cf. Culler, 1986, p. 15 ; Lyons, 1968, p. 38 ; Calvet, 1995, p. 507). El descubrimiento en 1996 de un nuevo fondo de manuscritos, parcialmente publicado en 2002 en los Écrits de linguistique générale, proporcionó a algunos lingüistas la ocasión de postular una nueva revolución: los manuscritos de Saussure, desenterrados un siglo después de haber sido escritos, contendrían potencial suficiente para conmocionar y restructurar (“bouleverser”) no sólo la lingüística contemporánea (Bouquet, 2004; Rastier, 2009), sino también las bases de la metafísica occidental (cf. Rastier, 2009). El propósito de este trabajo es el de revisar críticamente (si no de desactivar) los argumentos subyacentes a tal posición, para intentar de ese modo establecer cuáles son los criterios (¿biográficos, históricos, teóricos, filológicos?) que la sostienen. Intentaremos mostrar, en particular, que la apreciación de la importancia de un fondo de manuscritos científicos, como lo son en gran medida los de Saussure, no puede prescindir de una aproximación histórica, cuya carencia es evidente, justamente, en gran parte de los partidarios saussureanos (incluidos Rastier y Bouquet) de una nueva (o potencial) “revolución”. [less ▲]

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See detailCDS and financial stability
Sougné, Danielle ULg; Mattar, Jamal ULg

Conference (2012, August 01)

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See detailanswer to a question from the general reporter in session B2, question 1.6
Lilien, Jean-Louis ULg

Conference (2012, August)

Technology to forecast up to 2 days ahead the ampacity of power lines is now mature owing to european project TWENTIES

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See detailThe Proterozoic record of early eukaryotes
Javaux, Emmanuelle ULg

Conference (2012, August)

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See detailMicroeconometric Evidence of Financing Friction and Innovative Activity
Tiwari, Amaresh Kumar ULg

Conference (2012, August)

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See detailWeak localization with interacting Bose-Einstein condensates
Schlagheck, Peter ULg

Conference (2012, August)

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See detailInterstitial kinetic parameters for a 2-compartment insulin model with saturable clearance
Pretty, Christopher ULg; Le Compte, Aaron J.; Shaw, Geoffrey M. et al

Conference (2012, August)

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See detailMaturation du raisonnement biomédical évalué par la discussion d’une vignette clinique multidisciplinaire : étude longitudinale et relation avec la capacité de délimitation des connaissances
Collard, Anne ULg; Bourguignon, Jean-Pierre ULg

Conference (2012, August)

Contexte: Dans un curriculum médical comprenant des séminaires PBL, un Test de Concordance de Script nous avait permis de démontrer la maturation de la capacité de raisonnement, corrélée positivement avec ... [more ▼]

Contexte: Dans un curriculum médical comprenant des séminaires PBL, un Test de Concordance de Script nous avait permis de démontrer la maturation de la capacité de raisonnement, corrélée positivement avec la capacité de délimiter le champ de ses connaissances. L’objectif de la présente étude est de tester ces observations dans le contexte certificatif d’évaluation orale du raisonnement, sur base d’une vignette clinique discutée avec un collège d’enseignants. Résumé des travaux: Les données longitudinales d’évaluation de 279 étudiants ont été utilisées de la 2ème à la 5ème année du curriculum. Elles comprenaient les scores à l’examen oral de raisonnement ainsi que les degrés de certitude aux tests de connaissances (QCM). La capacité de délimitation du champ des connaissances a été calculée sur base de la différence entre les degrés de certitudes aux réponses correctes et les degrés de certitude aux réponses incorrectes au QCM. Résumé des résultats: Les résultats montrent, chez 213 étudiants qui réussissent d’emblée, une augmentation significative des performances à l’examen oral de raisonnement et une augmentation de la capacité de délimitation du champ des connaissances au cours des 4 années. Chez 66 étudiants qui échouent en 2ème année, cette capacité est plus faible et augmente l’année suivante après réussite de la 2ème année. Une corrélation positive entre les 2 indices étudiés est observée. Conclusions: Cette étude confirme, dans un contexte certificatif longitudinal au cours du curriculum médical, la maturation du raisonnement et celle de la capacité de délimiter le champ de ses connaissances. [less ▲]

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See detailConfesser le Prince : l’exemple de la cour de Bruxelles durant la première moitié du dix-septième siècle.
Pirlet, Pierre-François ULg

Conference (2012, August)

Durant l'époque moderne, la spiritualité des souverains et des puissants catholiques est associée à l'action de confesseurs. Ces religieux ont la charge d'administrer le sacrement de confession et d ... [more ▼]

Durant l'époque moderne, la spiritualité des souverains et des puissants catholiques est associée à l'action de confesseurs. Ces religieux ont la charge d'administrer le sacrement de confession et d'officier en tant que directeurs de conscience. Logés dans l'ombre du pouvoir, il échoit à ces ministres ecclésiastiques d'être les discrets garants de l'orthodoxie catholique du Prince. La responsabilité qui leur incombe les distingue des confesseurs de l'ordinaire, tandis que la singularité de la charge pose des questions quant à l'aménagement des pratiques pénitentielles : le Prince bénéficie-t-il d'une confession ad hoc dans le fond ou dans la forme ? Son statut dicte-t-il le modus operandi de son confesseur ? Ce dernier, en sus de ses compétences en matière de conseil politique, était-il choisi à l'aune de la spiritualité de son pénitent ? S'appuyant sur le dépouillement d'un large corpus de sources de la première moitié du xviième siècle – archives de diverses institutions religieuses et laïques, traités relatifs à la spiritualité et à la confession, écrits et méditations spirituelles composés par les confesseurs eux-mêmes – cette communication visera à dégager les contours et les particularités de la confession des souverains catholiques, en prenant comme objet d'étude les religieux chargés de la guidance spirituelle des princes et gouverneurs-généraux espagnols en poste à Bruxelles durant la première moitié du Grand Siècle. [less ▲]

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See detailProbing single molecules with AFM: force, dynamics, and function
Duwez, Anne-Sophie ULg

Conference (2012, August)

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See detailDo Mutual Fund Investors Still Trust Standard Risk-Adjusted Performance Measures?
Sougné, Danielle ULg; Bodson, Laurent ULg; Cave, Arnaud

Conference (2012, August)

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See detailInsulin Kinetics during Hyper-Insulinemia Euglycemia Therapy (HIET)
Penning, Sophie ULg; MASSION, Paul ULg; Le Compte, Aaron J. et al

Conference (2012, August)

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See detailLes portails occidentaux de la cathédrale d’Amiens : bilan historiographique
Lekane, Marie ULg

Conference (2012, August)

Depuis le milieu du XIXe siècle, les portails occidentaux amiénois ont régulièrement fait l’objet de publications. Jusque récemment, les études consacrées aux sculptures se bornaient à décrire les sujets ... [more ▼]

Depuis le milieu du XIXe siècle, les portails occidentaux amiénois ont régulièrement fait l’objet de publications. Jusque récemment, les études consacrées aux sculptures se bornaient à décrire les sujets iconographiques, comme si les statues étaient l’illustration stricte des Ecritures Saintes. Cette manière de faire est symptomatique d’une approche conférant aux programmes sculptés une fonction didactique. Si la notion de « Bible des illettrés » n’est pas unanimement rejetée, elle est largement remise en question par la communauté scientifique en raison de la complexité des programmes, souvent conjuguée à un éloignement physique des statues, comme c’est le cas à Amiens. Depuis une vingtaine d’années, la fonction des images en général, et des sculptures en particulier, est revue et élargie. Les historiens de l’art mènent des études comparées entre sculptures et sources liturgiques ou théologiques (en ce qui concerne Amiens : W. Schlink, 1991; S. Murray, 1996 ; B. Boerner, 2010). Parmi les fonctions de l’image, on peut également citer le lien étroit entre sculpture et prédication, mis en lumière, pour Amiens, par S. Murray en 2005. De plus, les spécialistes utilisent d’autres approches pour affiner leur connaissance matérielle de l’œuvre. Parmi celles-­‐ci, l’archéologie du bâti, ou Baugeschichte, l’analyse technique des pigments ainsi que l’étude stylistique ont permis d’alimenter les débats sur la chronologie, la mise en place des portails et les transferts artistiques afin de se faire une idée globale des portails. La statuaire amiénoise n’a cependant pas encore profité d’une étude globale, circonstanciée et renouvelée. Il s’agit pour nous de la mettre en œuvre dans le cadre de notre thèse afin de mieux saisir son rôle dans la sculpture du XIIIe siècle. [less ▲]

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See detailDifferences in bovine milk fat composition among dairy breeds in The Netherlands
Maurice-Van eijndhoven, Myrthe; Bovenhuis, Henk; Soyeurt, Hélène ULg et al

Conference (2012, August)

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See detailA study on the ecology of northern pigtail macaque (Amcaca nemestrina) in Khao Yai National PArk
Savini, Tommaso ULg; albert, aurélie; José Dominguez, Juan Manuel et al

Conference (2012, August)

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See detailDetermination of the composition of cryolitic melts involved in the Hall-Heroult process by Raman spectroscopy
Malherbe, Cédric ULg; Gilbert, Bernard ULg

Conference (2012, August)

Considering our experience in the study of such highly corrosive media by Raman spectroscopy and since the bath spectrum is function of the molar NaF/AlF3 ratio and the Al2O3 content, we have proposed in ... [more ▼]

Considering our experience in the study of such highly corrosive media by Raman spectroscopy and since the bath spectrum is function of the molar NaF/AlF3 ratio and the Al2O3 content, we have proposed in the past to apply that technique to the direct determination of the melt composition . Recent instrumental developments on CCD based spectrometers have made the proposed method more feasible. This presentation will first demonstrate that, employing an updated instrument provided with new optical filters and a more sensitive CCD detector, better quality spectra are obtained. Afterward, new results relevant to the development of our analytical method for the direct determination of the molar NaF/AlF3 ratio and the Al2O3 content in cryolitic melt will be discuss. Different aspects of the calculation procedure will be illustrated:  Estimation and subtraction method of the Rayleigh decay from melt spectra;  Development of an internal normalisation procedure based on equilibria in the melt and assisted by home-made software;  Establishment of calibration curves for the determination of the molar ratio NaF/AlF3 in the melt;  Establishment of calibration curves for the determination of oxide content in the melt;  Overall procedure for the composition determination. [less ▲]

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See detailAgriculture Urbaine, un métier d'avenir
Fiers, Marie; Claeys, Jean-Paul; Jijakli, Haissam ULg

Conference (2012, August)

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See detailÊtre femme en contexte postcolonial africain et être confronté à la succession : au-delà des aspects juridiques, vécu et gestion psychosociaux.
Bomda, Joseph ULg

Conference (2012, August)

L’Afrique postcoloniale francophone vit le cinquantenaire de son indépendance dans un contexte de dualité de normes successorales (tradition vs. modernité). Si l’expert du droit dit comment les conflits ... [more ▼]

L’Afrique postcoloniale francophone vit le cinquantenaire de son indépendance dans un contexte de dualité de normes successorales (tradition vs. modernité). Si l’expert du droit dit comment les conflits (résiduels, virtuels et habituels) qui en résultent sont gérés, le vécu intrinsèque des victimes lui importe peu. Cette communication, issue de nos travaux de thèse (Ph.D) en psychologie sociale sur l’éveil, le vécu et la gestion de la dissonance cognitive en contexte postcolonial africain, rend compte d’une sélection de réponses des femmes camerounaises, 382, victimes de l’opposition entre les normes du droit moderne et celles du droit traditionnel en rapport avec la jeune fille et la veuve. À l’occasion, les différences anthropologiques fondatrices des visions du monde traditionnelle et moderne de la succession permet d’identifier les points de contrastes entre les deux normes et de comprendre le malaise qui en résulte socioculturel. Au terme des analyses statistiques, les résultats indiquent que ces femmes souffrent de l’inconfort psychologique, des affects négatifs liés à soi, des affects liés à l’anxiété, des affects négatifs liés à soi et aux autres et, curieusement des affects positifs. La gestion de ces affects passe entre autres par la revalorisation de la tradition et de la modernité, l’évitement des situations aggravantes, le partage social des émotions, le prosélytisme et la confusion entre la tradition et la modernité. L’embarras place ainsi la gent féminine dans un embarras qui déteint sur leur rapport à elle et sur leurs rapports aux autres. Il urge conséquemment de voir le projet de code de la famille et des personnes prendre corps en partant d’un effort de conciliation des différences relevées entre les deux en jeu. [less ▲]

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See detailGrave Soils Analysis by TD-GCxGC-TOFMS
Stefanuto, Pierre-Hugues ULg; Scotsmans, E. M.J.; Wilson, A. S. et al

Conference (2012, August)

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See detailOptimization of a formic/acetic acid treatment of beech wood for lignin extraction
Simon, Mathilde ULg; Richel, Aurore ULg; Vanderghem, Caroline ULg et al

Conference (2012, August)

Lignocellulosic substrates are a promising alternative resource for the sustainable production of energy (biofuels), bio-based products and organic compounds. In the past, the extraction and recycling of ... [more ▼]

Lignocellulosic substrates are a promising alternative resource for the sustainable production of energy (biofuels), bio-based products and organic compounds. In the past, the extraction and recycling of cellulose (into fermentable glucose) constituted the central axis of lignocellulosic biorefinery processes. Degraded hemicelluloses and lignins were recovered as side-products with no possibilities of high-added value applications. Within the context of an integrated biorefinery, and for economic reasons, the recovery and the non-energetic valorization of lignins have opened recently new horizons. Lignin is a cross-linked phenolic polymer and is considered as potential alternative to petrochemical polymers or as a source of antioxidants for cosmetics and food industry, resins, chelating agent... As the final application of lignin depends on both extraction process and type of lignocellulosic sources, the development of fast and efficient physicochemical characterization methods is thus a prerequisite to optimize extraction processing conditions. In this study, beech wood particles (Fagus sylvatica L.) are delignified at atmospheric pressure by a formic acid/acetic acid/water mixture. Firstly, response surface methodology is used to optimize cooking time and temperature for delignification, pulp yield and concentration of degradation products (2-furfural and 5-hydroxymethylfurfural). The results highlight that best delignification is obtained in the highest cooking times and temperatures and that 5-hydroxymethylfurfural is produced during the formic/acetic acid treatment but is also degraded into 2-furfural. With the aim to develop an integrated biorefinery approach, multi-criteria optimization is used to find ideal cooking time and temperature (5h07, 104.2°C) leading to the maximization of delignification and pulp yield and to the minimization of 2-furfural production Finally, physicochemical and chemical structures of extracted lignins are found dependent on treatment conditions harshness. [less ▲]

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See detailProteomics of aphid salivary proteins
Francis, Frédéric ULg; De Pauw, Edwin ULg; Vandermoten, Sophie ULg et al

Conference (2012, August)

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See detailEvaluation of the social impact of HPAI surveillance network at the community level in Vietnam.
Antoine-Moussiaux, Nicolas ULg; Delabouglise, Alexis; Binot, Aurélie et al

Conference (2012, August)

The need to set up efficient and sustainable surveillance networks is a major concern which must be continually placed at the heart of the overall issue of development. In developing countries, the ... [more ▼]

The need to set up efficient and sustainable surveillance networks is a major concern which must be continually placed at the heart of the overall issue of development. In developing countries, the political priority to reduce poverty means that it is vital to include social aspects in public decision making on health management in general. This focus on social aspects can be considered all the more important regarding surveillance as it is deeply embedded in agents’ everyday life. The flow of information about animal health involves different non-monetary costs, ensuing from stigmatization or from social pressure to withhold or disclose information. Understanding, measuring and alleviating these social costs of information is required to ensure the effectiveness and viability of surveillance. The present study considers the case of highly pathogenic avian influenza surveillance in Vietnam. It aims at establishing a protocol allowing for understanding and quantifying social costs incurred by surveillance agents at the community level. In this prospect, tools and concepts from anthropology, participative epidemiology and experimental economics were combined. More particularly, social network analysis, participatory observation, companion modeling and stated preference surveys were applied for the thorough examination of constraints and costs of health information flows. The opportunity for the scaling-up of such methodologies and for the inclusion of the so-elicited quantitative values in socio-economic evaluation of surveillance systems are discussed. [less ▲]

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See detailImpact of sensor and measurement timing errors on model-based insulin sensitivity
Pretty, Christopher ULg; Le Compte, Aaron J.; Shaw, Geoffrey M. et al

Conference (2012, August)

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See detailUV radiation effects on liquid crystal variable retarders for aerospace applications
Garcia Parejo, Pilar; Alvarez-Herrero, Alberto; Uribe-Patarroyo, Nestor et al

Conference (2012, August)

Liquid-Crystal Variable Retarders (LCVRs)1 are optical devices that provide a variable optical retardance accomplished by the application of electric fields. Traditionally, they have been used as light ... [more ▼]

Liquid-Crystal Variable Retarders (LCVRs)1 are optical devices that provide a variable optical retardance accomplished by the application of electric fields. Traditionally, they have been used as light polarization modulators for polarimetric applications in ground telescopes2, and more recently they took part in the polarisation modulation package of the Imaging Magnetograph eXperiment (IMaX)3, where the LCVRs were launched successfully on-board the Sunrise mission, a stratospheric balloon that was flown from Antarctica to study the solar magnetic fields. This mission was the precursor of the Solar Orbiter mission of the European Space Agency (ESA), where the liquid crystals will be used as polarisation modulators onboard a space mission for the first time in two instruments: the Polarimetric and Helioseismic Imager (SO/PHI) and the Multi-Element Telescope for Imaging and Spectroscopy (METIS). Any on-board element used for aerospace applications must be able to survive the harsh environmental space conditions including UV radiation, gamma radiation, vibrational tests, thermal-vacuum... In this sense, LCVRs have been recently validated to be used under the space conditions of the Solar Orbiter mission, in the framework of the ESA project: “Validation of LCVRs for the Solar Orbiter Polarisation Modulation Package”. In this project, a set of LCVRs with different design parameters has been analyzed under the different space environmental conditions. These design parameters include the architecture of the LCVR cell, using Anti-Parallel Aligned Nematic (APAN) and Hybrid Aligned Nematic (HAN) architectures, the type of liquid crystal molecules, using different commercial nematic liquid crystal mixtures with high and low birefringence and positive and negative dielectric anisotropy, different homogeneous and homeotropic polyimide alignment layers and different glass plates. Among the space environmental components, the UV radiation needs special consideration due to the organic nature of the liquid crystal molecules and the alignment layers that consisted of rubbed polyimide layers. In this work, we present the main results of the UV radiation test campaign carried out in the LCVRs consisting of the performance of a thorough optical characterization of the LCVRs, including optical retardance and response times measurements at different voltages performed by the ellipsometry technique, and optical transmission measurements, before and after irradiating the LCVRs with UV light at different doses, in two different spectral ranges: 200 -400 nm and 160-200 nm. The main degradation effects observed in the LCVRs was a progressive reduction of the retardance range of the LCVRs which points out a decrease of the birefringence of the liquid crystal molecules or the increase of the pretilt angle due to the degradation of the polyimide layers, and an increase of the response times of the cells. Nevertheless, the changes observed do not involve the destruction of the LCVRs and they keep fulfilling the requirements for the Solar Orbiter mission becoming in a promising technology for aerospace applications. [less ▲]

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See detailOverview of smallholders’ local rice post-harvest activities in Benin: Gender, practices, commercialization and rice processors livelihoods
Zossou, Enangnon ULg; Vodouhe, Davo Simplice; Diagne, Aliou et al

Conference (2012, August)

Rice is a primary food source, vital vehicle in dealing with food security and eradicating poverty. In Benin rice is becoming increasingly important and its production and processing tasks are divided on ... [more ▼]

Rice is a primary food source, vital vehicle in dealing with food security and eradicating poverty. In Benin rice is becoming increasingly important and its production and processing tasks are divided on the basis of gender, with women being responsible for much of the drudgery involved in processing. To have an overview of gender and socio-economic dimensions of local rice processing in Benin, a study was conducted in the north and south of Benin with 240 smallholder rice processors randomly selected. In addition to structured interviews and weekly report sheets, the participatory assessment on sustainable livelihood approach was used to appreciate the different states of their financial, social, human, natural and physical capitals assets. Rice processors are mostly women (67% in the whole sample). Men are more representative in white rice processing while women are more representative in parboiled rice processing. Women rice processors have less acces to formal learning source and have bad practices during white rice processing. The traditional rice parboiling methods that don’t lead to good quality rice is prevalence. The main actors of local rice commercialization are the rice producers; the bodies of the Ministry of Agriculture; Famers Organisation and smallholder local rice processors who are generally young women. During local rice commercialization, women are more representative in the sale without contract in the processing village while men are more representative in the sale under a contract. The overall state of capitals is low with better scores in human, physical and natural capitals stocks for men and in social capital for women. [less ▲]

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See detailAutomates et systèmes de numération
Charlier, Emilie ULg

Conference (2012, August)

Ce cours d'1h30 est accessible à un grand public de mathématiciens, y compris les enseignants du secondaire. Je commencerai par définir ce que sont les automates finis. J'introduirai les systèmes de ... [more ▼]

Ce cours d'1h30 est accessible à un grand public de mathématiciens, y compris les enseignants du secondaire. Je commencerai par définir ce que sont les automates finis. J'introduirai les systèmes de numération en général. Je m'attarderai sur le cas des bases entières, et montrerai les propriétés remarquables de calculs dans ces bases, notamment le calcul de l'addition et de la multiplication par une constante par automate fini. Ensuite, j'étendrai ces considérations à des numérations dites non-standard et aux systèmes de Pisot. Enfin, je définirai les numérations abstraites. [less ▲]

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See detailCoparenting alliances assessment in heterosexual and same-sex parents triads
D'Amore, Salvatore ULg; Pardo, Seth; Favez, Nicolas

Conference (2012, July 27)

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See detailL’avenir du français dans le monde ? Le cœur et la raison
Defays, Jean-Marc ULg

Conference (2012, July 24)

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See detailTHE ADDITIONAL VALUE OF HYPERSPECTRAL DATA FOR SMART FARMING
Migdall, Silke; Klug, Philipp; Denis, Antoine ULg et al

Conference (2012, July 22)

The spectral information contained in hyperspectral data allows for a more detailed crop and soil parameter retrieval, in turn making possible to derive precise information about plant health (nutrient ... [more ▼]

The spectral information contained in hyperspectral data allows for a more detailed crop and soil parameter retrieval, in turn making possible to derive precise information about plant health (nutrient deficiencies, water stress, crop diseases) but also about soil status (from soil moisture to humus content). Thus, smart farming, that is farming practice that wants to account for the whole ecosystem on the field and react precisely to any challenges, can be supported by hyperspectral data with exactly the spatial information it needs. [less ▲]

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See detailIntersubjectivity and intersubjectification: typology and operationalisation
Brems, Lieselotte ULg; Ghesquière, Lobke; van de velde, Freek

Conference (2012, July 19)

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See detailExtension of Bayesian procedures to integrate and to blend multiple external information into genetic evaluations
Vandenplas, Jérémie ULg; Gengler, Nicolas ULg

Conference (2012, July 18)

Current genetic evaluations are mostly based on local data, potentially followed by an international second step, as it is performed by INTERBULL (Uppsala, Sweden) for dairy breeds. However, reliability ... [more ▼]

Current genetic evaluations are mostly based on local data, potentially followed by an international second step, as it is performed by INTERBULL (Uppsala, Sweden) for dairy breeds. However, reliability of estimated breeding values (EBV) for animals with few local data may be limited. Furthermore, the current development of genomic selection makes this issue more important and the blending of those multiple sources more necessary. Current methods are based on selection index and Bayesian procedures were proposed for a single external source. The aim of this research was to extend these methods to integrate information from multiple sources outside a given evaluation system, i.e. external information, into this genetic evaluation, i.e. internal evaluation, and to assess its potential to blend multiple sources of information when only external information is available. To allow simplifications of the computational burden and the propagation of all external information through the whole pedigree, all animals were considered as animals associated to external information thanks to the prediction of external information from available one for internal animals, i.e. animals with no external information. Multiple considerations of contributions due to relationships among animals were also taken into account. Two dairy cattle populations were simulated across 5 generations. Internal females were randomly mated with internal and 50 external males. Milk production for the first lactation for each female was simulated in both populations. Results for 100 replicates showed that average rank correlations among Bayesian EBV and EBV based on the joint use of external and internal data were close to 1 for both external and internal animals. The respective correlations for the internal evaluation were equal to 0.54 and 0.95. Mean squared error, expressed as a percentage of the internal mean squared error, was close to 0% for both external and internal animals. Thereby, the Bayesian procedure has the potential to integrate and to blend multiple sources of external information to evaluate animals more reliably. [less ▲]

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See detailEffect of milk recording schemes on milk and milk components genetic parameters in Luxembourg
Arnould, Valérie ULg; Gengler, Nicolas ULg; Soyeurt, Hélène ULg

Conference (2012, July 18)

A particularity of the Luxembourg milk recording is the use of different schemes. Two principal schemes are applied: the scheme “S” applied on 69.1% of the total herds (n=712) and consisting in one ... [more ▼]

A particularity of the Luxembourg milk recording is the use of different schemes. Two principal schemes are applied: the scheme “S” applied on 69.1% of the total herds (n=712) and consisting in one proportionate sample of all daily milkings, and the scheme “T” (21.6% of the total herds) which consists in one sample of only one milking (morning or evening milking) (and alternating milking time from month to month). The problematic is that application of different schemes could influence the milk components (protein and fat yield) and the milk fat components (saturated and unsaturated groups of fatty acids) genetic parameters estimation and to prevent all comparisons between dairy population under different milk recording schemes. A total of 47,613 and 44,833 test-day records were obtained, respectively for schemes “S” and “T” from Holstein cows in first lactation in Luxembourg dairy herds. The used model included as fixed effects: herd x date of test, class of age, and month x year. Random effects were permanent environmental, additive genetics, and residual effects. The main objective of this work is to study the effect the choice of milk recording schemes (“S” or “T” schemes) on milk yield and milk components genetic parameters. A solution could be to add a fixed effect taking in account the milking time. The second objective is to study the effect of milking time (morning or evening) on genetic parameters estimated in the case of scheme “T”. According to the results, genetic parameters were statistically different between the schemes “S” and “T” for milk yield (P value < 0.0001). Further, the classifications of bulls according to their breeding values were very different when values were estimated on basis of scheme “S” or “T” (Spearman correlation value of 0.51 for milk yield for example). In conclusion, using several milk recording schemes do not allow any comparison of genetic parameters between dairy cattle’s. [less ▲]

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See detailEstimation of genetic parameters for birth weight, pre-weaning mortality and hot carcass weight in a crossbred population of pigs
Dufrasne, Marie ULg; Misztal, Ignacy; Tsuruta, Shogo et al

Conference (2012, July 18)

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See detailGenetic parameters for methane indicator traits based on milk fatty acids in cows
Kandel, Purna Bhadra ULg; Vanlierde, Amélie ULg; Dehareng, Frédéric et al

Conference (2012, July 18)

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See detailBayesian integration of external information into the single step approach for genomically enhanced prediction of breeding values
Vandenplas, Jérémie ULg; Misztal, Ignacy; Faux, Pierre ULg et al

Conference (2012, July 17)

An assumption to compute unbiased estimated breeding values (EBV) is that all information, i.e. genomic, pedigree and phenotypic information, has to be considered simultaneously. However, current ... [more ▼]

An assumption to compute unbiased estimated breeding values (EBV) is that all information, i.e. genomic, pedigree and phenotypic information, has to be considered simultaneously. However, current developments of genomic selection will bias evaluations because only records related to selected animals will be available. The single step genomic evaluation (ssGBLUP) could reduce pre-selection bias by the combination of genomic, pedigree and phenotypic information which are internal for the ssGBLUP. But, in opposition to multi-step methods, external information, i.e. information from outside ssGBLUP, like EBV and associated reliabilities from Multiple Across Country Evaluation which represent a priori known phenotypic information, are not yet integrated into the ssGBLUP. To avoid multi-step methods, the aim of the study was to assess the potential of a Bayesian procedure to integrate a priori known external information into a ssGBLUP by considering simplifications of computational burden, a correct propagation of external information and no multiple considerations of contributions due to relationships. To test the procedure, 2 dairy cattle populations (referenced by “internal” and “external”) were simulated as well as milk production for the first lactation of each female in both populations. Internal females were randomly mated with internal and 50 external males. Genotypes of 3000 single-nucleotide polymorphisms for the 50 males were simulated. A ssGBLUP was applied as the internal evaluation. The external evaluation was based on phenotypic and pedigree external information. External information integrated into the ssGBLUP consisted to external EBV and associated reliabilities of the 50 males. Results showed that rank correlations among Bayesian EBV and EBV based on the joint use of external and internal data and genomic information were higher than 0.99 for the 50 males and internal animals. The respective correlations for the internal evaluation were equal to 0.50 and 0.90. Thereby, the Bayesian procedure can integrate external information into ssGBLUP. [less ▲]

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See detailFeasibility of genomic prediction of fatty acids composition in milk of dairy cattle from Luxembourg using single-step procedure
Faux, Pierre ULg; Arnould, Valérie ULg; Soyeurt, Hélène ULg et al

Conference (2012, July 16)

Milk composition in fatty acids (FA) portrays a class of novel traits of interest for both human health and animal robustness. With the exception of Wallonia, Luxembourg is currently the only place in the ... [more ▼]

Milk composition in fatty acids (FA) portrays a class of novel traits of interest for both human health and animal robustness. With the exception of Wallonia, Luxembourg is currently the only place in the world where, using mid-infrared spectrometry, milk composition in 29 FA is routinely recorded for dairy cows. Since 2007, spectral data has been recorded so far on 87,368 cows from 690 different herds, by 2 main control methods (T-method: one sample of only one milking, morning or evening, and S-method: proportionate sample of all daily milkings). Additionally, milk, fat and protein yields are available since 1990. The availability of FA allows many options for management use and animal breeding but requires advanced modeling (e.g., adapted to the testing methods). In the context of animal breeding, genomic selection has been widely developed in dairy cattle, where single-step approach (ssGBLUP) is particularly well suited for small-sized populations, as the dairy cattle population of Luxembourg (365,892 animals currently in pedigree) and is completely integrated into mixed modeling of phenotypic data. The objectives of this study were: (1) to assess the potential benefits of a single-step genomic evaluation on milk FA composition in a small-sized population and in particular (2) to quantify the impact of genomic information on reliability (REL) of estimated breeding values (EBV) of FA in Luxembourg. In a preliminary study for a single FA, oleic acid (C18:1 cis 9) genetic evaluations were performed on 47,613 milk records; collected by S-method, from 8,000 cows in first parity with a random regression test-day model using second order Legendre polynomials. For this sample, molecular data was simulated for 422 AI sires, ancestors of recorded cows. Prediction error variances (PEV) were used to compute REL and effective daughter contributions (EDC). First results showed a low increase in REL and EDC. Extension of this research to all sampling methods and research on the optimum structure of the reference population (bulls, cows) will be done to fit the Luxembourg-specific situation. [less ▲]

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See detailLa caméra et l'ouvrier: des "Sorties d'usine" à "Oeil/Machine III"
Hamers, Jérémy ULg

Conference (2012, July 13)

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See detailStress et santé des dirigeants de PME
Angenot, Arnaud ULg; Schippers, Nathalie ULg; Eubelen, Isabelle et al

Conference (2012, July 12)

Comme l’atteste l’Institut National de la Santé et de la Recherche Médicale ([INSERM], 2011), il est aujourd’hui devenu nécessaire de pouvoir mieux identifier les sources de stress chez les travailleurs ... [more ▼]

Comme l’atteste l’Institut National de la Santé et de la Recherche Médicale ([INSERM], 2011), il est aujourd’hui devenu nécessaire de pouvoir mieux identifier les sources de stress chez les travailleurs indépendants. Parmi ceux-ci, les dirigeants de Petites et Moyennes Entreprises (PME) sont fréquemment victimes de problèmes de santé liés à une charge physique et mentale élevées (Bournois, Duval-Hamel, Scarengella & Roussillon, 2007 ; Gunnarsson, Vingard & Josephson, 2007). S’appuyant sur ces constats, cette étude a eu pour objectif d’évaluer leur sentiment d’épuisement professionnel et de déterminer les causes de stress spécifiques au milieu entrepreneurial. Pour ce faire, une enquête par questionnaire écrit a été menée à la demande de différentes organisations patronales belges du secteur de la construction et de la vente. [less ▲]

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See detailA research project : young children in situation of handicap taking an active part in their everyday life
Camus, Pascale ULg

Conference (2012, July 12)

Despite the fact that Belgium has ratified the Convention on the Rights of theCchild in 1992, few children with special needs, aged 0-3, are effectively taken care in ECEC services. When it appears that ... [more ▼]

Despite the fact that Belgium has ratified the Convention on the Rights of theCchild in 1992, few children with special needs, aged 0-3, are effectively taken care in ECEC services. When it appears that they have access to services, care is focused on their deficiency, professionals often consider access as a favour done to the child and its family who is seen first as having special needs (instead of being first a child with competences). The workshop has proposed to explore and question the nature and the extent of participation for those children that are taken care in ECEC services (out of their families). Some questions have been explored and discussed: - Is little children's participation more rhetoric than reality? What are the representations about rights of children in situation of handicap to participate? What if we compare to protection and provision rights? - What does “participation” mean for little children in situation of handicap in an ECEC service? - How the representations adults have can work on conditions to participate? The necessity to adopt a thinking where the focus is placed on each child’s competences and interests … [less ▲]

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See detailMicrowave-treatment of frozen wood packaging material
Henin, Jean-Marc; Bauduin, Aline; Leyman, Michaël ULg et al

Conference (2012, July 12)

As part of the wood packaging material (WPM) regulation in international trade, the dielectric heating (DH) is soon to be included in ISPM15 (IPPC 2009) as an approved phytosanitary treatment. It has been ... [more ▼]

As part of the wood packaging material (WPM) regulation in international trade, the dielectric heating (DH) is soon to be included in ISPM15 (IPPC 2009) as an approved phytosanitary treatment. It has been considered that when using dielectric radiation (i.e. microwaves or radiofrequencies), reaching 60°C or more throughout the entire profile of the wood during at least 60s (i.e. 60°C/60s) ensures the eradication of any noxious organism present in the wood. Regarding the treatment itself, the main requirements mentioned in the draft of ISPM15 Annex 1 (IPPC 2011) concern the way to achieve “uniformity of heating” as well as the treatment duration, which must not exceed 30min. Concerning wood characteristics, the only restriction to the DH concerns the thickness of the wood pieces, which must not exceed 20cm; no other restriction exists regarding wood moisture content, density or initial temperature. As reported in the draft of ISPM15 Annex 1, it is generally considered that “when using microwaves as a heating source, the coldest part of the wood is the surface”. This statement implies that achieving 60°C (or more) during 60s at the surface of the wood should guarantee compliance with IPPC requirements (i.e. 60°C throughout the profile of the wood). However, since ice and liquid water exhibit very different properties towards microwaves, initially frozen wood (9cmX9cm and 17cmX17cm in cross-section) was irradiated in a 28.8 kW microwave oven (2.45GHz) in order to assess whether achieving 60°C/60s at the surface of less than 20cm-thick planks ensures higher core temperatures. The temperature pattern observed after the treatment was compared with the one observed after the treatment of initially thawed wood pieces. It was observed that, in some conditions, initially frozen pieces exhibit inside temperature (much) lower than 60°C, despite complying with 60°C/60s all over the surface of the wood. These results show that when wood is heated with microwaves, its coldest part may not be the surface. Our results also strongly suggest that the impact of wood properties on post-treatment temperature pattern should be further investigated in order to better identify the limits of the DH (at least on frozen wood). [less ▲]

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See detailFull discontinuous Galerkin formulation of shells in large deformations with parallel and fracture mechanics applications
Becker, Gauthier ULg; Noels, Ludovic ULg

Conference (2012, July 11)

Fracture mechanical problems can be solved by coupling the finite elements with a cohesive approach. Unfortunately, the classical cohesive methods suffer from severe limitations. Indeed, on one hand, the ... [more ▼]

Fracture mechanical problems can be solved by coupling the finite elements with a cohesive approach. Unfortunately, the classical cohesive methods suffer from severe limitations. Indeed, on one hand, the intrinsic approach, which inserts the cohesive elements at the beginning, has to model the prefracture stage. This requires an initial slope in the traction separation law that should tend toward infinity to avoid lack of consistency leading to obvious numerical problems. On the other hand, the extrinsic cohesive method inserts the cohesive elements during the simulation when a fracture criterion is reached. This insertion requires topological mesh modifications and therefore a very complicated implementation, especially in a parallel code. To overcome these limitations, new methods were developed and in particular, an approach based on discontinuous Galerkin formulation (DG) has been pioneered by R. Radovitzky (Radovitzky cmame2011). The use of the DG principle allows to formulate the problem with discontinuous elements and the continuity between them is ensured weakly by terms integrated on the elements interface . These interface elements can be easily replaced by a cohesive element during the simulation. We have recently developed this approach for shells (Becker cmame2011) to obtain a full DG method. Moreover, a new cohesive law based on the reduced stresses of the thin bodies formulation is developed to propagate a fracture through the thickness. This cohesive model dissipates the right amount of energy during crack phenomena. These developments are implemented in parallel and validated by the study the blast of a notched cylinder, for which experimental and numerical (by XFEM method) data are reported in the literature by R. Larsson (Larsson ijnme2011). Finally, as thin structures are often made of ductile materials, which show large deformations before fracture, the formulation is extended to the non linear case with hyperelastic material law. This one can take into account the damage and a criterion based on the work of Huespe (Huespe plasticity2009) is developed to localize the damage leading to the apparition and propagation of cracks. [less ▲]

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