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See detailMicro-plasto-hydrodynamic lubrication: a fundamental mechanism in cold rolling
Laugier, Maxime; Boman, Romain ULg; Legrand, Nicolas et al

in Advanced Materials Research (2014), 966-967

Micro Plasto-Hydrodynamic (MPH) lubrication is a general mechanism in metal forming that consists in a re-lubrication of tool-piece solid contacts by an outflow of lubricant from pressurized “pockets” ... [more ▼]

Micro Plasto-Hydrodynamic (MPH) lubrication is a general mechanism in metal forming that consists in a re-lubrication of tool-piece solid contacts by an outflow of lubricant from pressurized “pockets” promoted by the plastic deformation. MPH lubrication is one of the main sources of friction variation (e.g. uncontrolled friction) in metal forming processes like strip drawing or cold rolling. This paper presents experimental results giving evidence of the MPH lubrication mechanism in cold rolling and a new lubrication model that predicts for strip drawing conditions MPH lubrication initiation and lubricant extension along the solid contacts initially in boundary condition. This MPH model could be implemented in a cold rolling model soon to help in high strength steels developments on cold rolling mills. [less ▲]

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See detailCrise ou catharsis ?
Vanmeerbeek, Marc ULg

in Exercer (2014), 113(Editorial), 99

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See detailBayes Adaptive Reinforcement Learning versus Off-line Prior-based Policy Search: an Empirical Comparison
Castronovo, Michaël ULg; Ernst, Damien ULg; Fonteneau, Raphaël ULg

in Proceedings of the 23rd annual machine learning conference of Belgium and the Netherlands (BENELEARN 2014) (2014, June)

This paper addresses the problem of decision making in unknown finite Markov decision processes (MDPs). The uncertainty about the MDPs is modeled using a prior distribution over a set of candidate MDPs ... [more ▼]

This paper addresses the problem of decision making in unknown finite Markov decision processes (MDPs). The uncertainty about the MDPs is modeled using a prior distribution over a set of candidate MDPs. The performance criterion is the expected sum of discounted rewards collected over an infinite length trajectory. Time constraints are defined as follows: (i) an off-line phase with a given time budget can be used to exploit the prior distribution and (ii) at every time step of the on-line phase, decisions have to be computed within a given time budget. In this setting, we compare two decision-making strategies: OPPS, a recently proposed meta-learning scheme which mainly exploits the off-line phase to perform policy search and BAMCP, a state-of-the-art model-based Bayesian reinforcement learning algorithm, which mainly exploits the on-line time budget. We empirically compare these approaches in a real Bayesian setting by computing their performances over a large set of problems. To the best of our knowledge, it is the first time that this is done in the reinforcement learning literature. Several settings are considered by varying the prior distribution and the distribution from which test problems are drawn. The main finding of these experiments is that there may be a significant benefit of having an off-line prior-based optimization phase in the case of informative and accurate priors, especially when on-line time constraints are tight. [less ▲]

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See detailL’Anonyme de Londres (P. Lit. Lond. 165, Brit. Libr. inv. 137). Édition et traduction d’un papyrus médical grec du Ier siècle
Ricciardetto, Antonio ULg

Book published by PULg (2014)

Acquis en 1889 par le British Museum, l’Anonyme de Londres est, à ce jour, le plus long papyrus médical grec conservé. Daté du Ier siècle de notre ère et provenant peut-être d’Hermopolis, en Moyenne ... [more ▼]

Acquis en 1889 par le British Museum, l’Anonyme de Londres est, à ce jour, le plus long papyrus médical grec conservé. Daté du Ier siècle de notre ère et provenant peut-être d’Hermopolis, en Moyenne Égypte, il contient un texte autographe où sont exposées et discutées de nombreuses théories nosologiques, étiologiques et physiologiques, qui ont pour auteurs au moins vingt-cinq médecins et philosophes, dont peu sont postérieurs au IVe siècle avant notre ère et dont plusieurs sont inconnus par ailleurs. Après une introduction générale sur l’Anonyme de Londres, où sont notamment étudiés les circonstances relatives à la découverte et à l’étude du papyrus, ainsi que ses caractéristiques matérielles et son contenu, le livre présente l’édition critique, accompagnée de la première traduction française, des textes grecs du recto et du verso de ce témoin exceptionnel pour notre connaissance de la médecine et de la librairie antiques. Il est complété par deux bibliographies, l’une, relative aux textes du papyrus, l’autre, générale, par des index, en français et en grec, et par un fascicule de planches. [less ▲]

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See detailDéfaire le discours d'autorité. Les 'Physiologies' à la limite de l'essai
Stienon, Valérie ULg

in Glaudes, Pierre; Lyon-Caen, Boris (Eds.) Essai et essayisme en France au XIXe siècle (2014)

Les Physiologies déferlent sous la Monarchie de juillet, alimentant les dépôts de pittoresques et prolongeant les caricatures en vitrine des passages parisiens. Si, presqu’un siècle plus tard, l’emprunt ... [more ▼]

Les Physiologies déferlent sous la Monarchie de juillet, alimentant les dépôts de pittoresques et prolongeant les caricatures en vitrine des passages parisiens. Si, presqu’un siècle plus tard, l’emprunt littéraire à la «physiologie» compose encore un effet de titre pour un essai théorique tel que la Physiologie de la critique d’Albert Thibaudet (1920), le petit genre du même nom, qui présente d’autres caractéristiques formelles et thématiques, n’est pas nettement défini par rapport à une conception et une pratique de l’essai. Au mieux peut-on lui trouver certaines parentés avec la chronique sous la forme de la notation des faits-Paris et avec une fiction d’actualité féconde en savoirs culturels et sociaux. Cette indétermination générique est particulièrement intéressante en raison de la diversité des paramètres poétiques et contextuels sur lesquels elle repose. Ce sont ces aspects qui font l’objet du présent parcours synthétique dans un corpus foisonnant, en préalable à une étude plus spécifiquement dédiée aux infinies nuances qui caractérisent ces textes. [less ▲]

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See detailMallarmé dans la prison des signes
Durand, Pascal ULg

in Cahiers du CérédI (2014, June), 10

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See detailPhysician Induced Demand for C-Sections: Does the Convenience Incentive Matter?
Lefevre, Mélanie ULg

Scientific conference (2014, June)

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See detailModeling of the Iturinic Antimicrobial Lipopeptide Mycosubtilin at Interfaces
Loison, Claire; Nasir, Mehmet Nail ULg; Benichou, Emmanuel et al

Conference (2014, June)

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See detailExecutive function and grey matter atrophy in healthy aging: A voxel-based morphometry analysis
Manard, Marine ULg; Bahri, Mohamed Ali ULg; Salmon, Eric ULg et al

Poster (2014, June)

Introduction Executive functioning is one of the cognitive domain that declines in healthy aging (Salthouse, Atkinson, & Berish, 2003). In addition, neuroimaging studies pointed out diverse ... [more ▼]

Introduction Executive functioning is one of the cognitive domain that declines in healthy aging (Salthouse, Atkinson, & Berish, 2003). In addition, neuroimaging studies pointed out diverse neurobiological modifications associated to normal aging, such as reduced grey and white matter volumes and cortical thickness (Raz & Rodrigue; 2006). In that context, Voxel Based Morphometry (VBM; Ashburner & Friston, 2000) and Partial Least Square (PLS; McIntoch at al., 1996, 2004) were used to investigate the effect of grey matter atrophy on executive abilities in normal aging. Methods Thirty six young (age range: 18-30) and 43 healthy older (age range: 60-78) adults were included in this study. Executive functioning was assessed by inhibition, updating and shifting tasks (Miyake et al., 2000), and a composite score for general executive ability was created. Structural high resolution T1-weighted images were acquired with a 3T head-only scanner using a standard transmit-receive quadrature head coil (Siemens, Allegra, Erlangen, Germany). The structural images were segmented using VBM8 toolbox, normalized to the MNI stereotaxic space and the resulting grey matter volume images were smoothed (Gaussian kernel: FWHM 8mm). PLS analyses were performed to determine regional grey matter volume differences between young and older adults, and next to identify the regional grey matter volumes specifically associated to executive performance in older participants (p<0.001). PLS is a validated multivariate approach that robustly identifies whole brain activity patterns correlated with behavioral data or experimental design (i.e., scores, conditions or tasks). Results Behavioral data showed a significant age-related decline in executive functioning (t=-5.43; p<.001). MRI analyses showed that significant age-related grey matter volume decrease was mostly observed across a large network including frontal, parietal, and temporal regions. Moreover significant positive correlations between the executive score and the grey matter volumes in older participants were found in a subset of these cortical areas: the inferior, middle and superior frontal cortex, the pre and postcentral gyri, the anterior and middle cingulate cortex, the inferior and superior parietal regions, the retrosplenial cortex, and finally, the inferior, middle and superior temporal regions. Discussion This study first replicated that executive abilities decline with age (Salthouse et al., 2003). This age-related executive decline is related to specific cerebral regions within a large fronto-temporo-parietal network sensitive to age. Interestingly, the areas whose atrophy is linked to executive abilities are quite similar to those evidenced in functional neuroimaging studies in young participants (see Collette & Van der Linden, 2002; Collette, Hogge, Salmon, & Van der Linden, 2006 for reviews). Therefore, using PLS multivariate analyses, we demonstrated that executive changes in normal aging are not dependent on atrophy in frontal areas only but rather comes from a grey matter volume decrease in a large antero-posterior brain network. [less ▲]

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See detailCAMKKβ/AMPK-α1 pathway regulates phosphorylation of cytoskeletal targets in thrombin-stimulated human platelets
Onselaer, Marie-Blanche; Oury, Cécile ULg; Hunter, Roger W et al

in Journal of Thrombosis and Haemostasis [=JTH] (2014), 12(6), 973-986

Background. Platelet activation requires sweeping morphological changes, supported by contraction and remodelling of platelet actin cytoskeleton. In various other cell types, AMP-activated protein kinase ... [more ▼]

Background. Platelet activation requires sweeping morphological changes, supported by contraction and remodelling of platelet actin cytoskeleton. In various other cell types, AMP-activated protein kinase (AMPK) controls the phosphorylation state of cytoskeletal targets. Objective. We hypothesized that AMPK is activated during platelet aggregation and contributes to the control of cytoskeletal targets. Results. We found that AMPK-α1 was mainly activated by thrombin and not by other platelet agonists in purified human platelets. Thrombin activated AMPK-α1 ex vivo via a Ca2+/calmodulin-dependent kinase kinase β (CAMKKβ)-dependent pathway. Pharmacological inhibition of CAMKKβ blocked thrombin-induced platelet aggregation and counteracted thrombin-induced phosphorylation of several cytoskeletal proteins, namely, regulatory myosin light chains (MLC), cofilin and vasodilator-stimulated phosphoprotein (VASP), three key elements involved in actin cytoskeleton contraction and polymerization. Platelets isolated from mice lacking AMPK-α1 exhibited reduced aggregation in response to thrombin, associated with a defect in MLC, cofilin and VASP phosphorylation and actin polymerization. More importantly, we show for the first time that AMPK pathway was activated in platelets of patients undergoing major cardiac surgery, in a heparin-sensitive manner. Conclusion. AMPK-α1 is activated by thrombin in human platelets. It controls phosphorylation of key cytoskeletal targets and actin cytoskeleton remodelling during platelet aggregation. [less ▲]

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See detailStructural analysis of some bis-(8-isopropyl-isoquinolinium) derivatives reveals a preferential folded conformation leading to a stereoselective attack by sodium borohydride
Dilly, Sébastien ULg; Badarau, Eduard; Dufour, Fabien et al

in Journal of Molecular Structure (2014)

Reduction of symmetrical bis-isoquinolinium derivatives with sodium borohydride generates normally a mixture of three 1,2,3,4-tetrahydroisoquinoline stereoisomers. In a series of 8- isopropyl analogues ... [more ▼]

Reduction of symmetrical bis-isoquinolinium derivatives with sodium borohydride generates normally a mixture of three 1,2,3,4-tetrahydroisoquinoline stereoisomers. In a series of 8- isopropyl analogues, chiral resolution failed for the analogues with propyl and m-xylyl linkers since two and one peaks respectively were detected by HPLC. Further analysis by MS and CD of both peaks of the propyl analogue revealed that each peak corresponds to an enantiomer. Conformational analysis and X-ray cristallography showed a folded conformation of the propyl and m-xylyl analogues responsible for the observed stereoselectivity following the reduction step. Additional 1H NMR investigations confirm structural features detected by theoretical analysis. [less ▲]

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See detailCan we interpret linear kernel machine learning models using anatomically labelled regions?
Schrouff, Jessica ULg; Monteiro, Joao; Joao Rosa, Maria et al

Poster (2014, June)

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See detailThe Impact of Dual-Tasking on Verbal Short-Term Memory in Children with Specific Language Impairment
Leclercq, Anne-Lise ULg; Maillart, Christelle ULg; Lange, Manon et al

Poster (2014, June)

Limitations in general processing capacities have been proposed to account for poor verbal short-term memory (STM) performances in children with SLI. Previous studies observed that STM performances ... [more ▼]

Limitations in general processing capacities have been proposed to account for poor verbal short-term memory (STM) performances in children with SLI. Previous studies observed that STM performances decreased to a larger extent in children with SLI as compared to their unaffected peers when the processing demands of the task increased (e.g., Ellis Weismer, et al., 2005; Montgomery, 2000a,b). However, in these studies, the increase in attention processing demands went with an increase in linguistic processing demands. Since children with SLI experience language processing problems, it is not clear whether general attention problems or language processing problems are at the root of their larger performance decrease as compared to their unaffected peers. This study aims at directly assessing the hypothesis that limitations in general attentional capacity are at the root of poor STM performances in children with SLI, using an attention demanding visual search task administered concurrently with nonword repetition task. Twenty-three children with SLI, 23 age-matched children, and 23 nonword span-matched children performed immediate serial recall tasks of nonwords. The STM lists were presented either alone or concurrently with the target detection task. Moreover, the target detection task either stopped or continued when children had to recall the nonwords. Results show a main effect of dual task condition on both nonword repetition accuracy and target detection accuracy. Performances in children with SLI were not more affected than in controls by the necessity to perform a concurrent visual attention task during nonword lists presentation. However, nonword recall seemed to be more challenging for children with SLI than for age-matched controls. Indeed, performances in the visual task were lower in children with SLI than in their age-matched controls, but not as compared to nonword span-matched controls. [less ▲]

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See detailReceptor expression in craniopharyngiomas causing tumor growth in pregnancy: case report and review of the literature
VROONEN, Laurent ULg; TOME, Monica; THIRY, Albert ULg et al

in Abstract book : 57èmes Journées Internationales d'Endocrinologie Clinique - Henri-Pierre Klotz (2014, June)

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See detailIdentifying endophenotypes of autism: a multivariate approach
Segovia-Román, Fermín ULg; Holt, Rosemary; Spencer, Michael et al

in Frontiers in Computational Neuroscience (2014), 8

The existence of an endophenotype of autism spectrum condition (ASC) has been recently suggested by several commentators. It can be estimated by finding differences between controls and people with ASC ... [more ▼]

The existence of an endophenotype of autism spectrum condition (ASC) has been recently suggested by several commentators. It can be estimated by finding differences between controls and people with ASC that are also present when comparing controls and the unaffected siblings of ASC individuals. In this work, we used a multivariate methodology applied on magnetic resonance images to look for such differences. The proposed procedure consists of combining a searchlight approach and a support vector machine classifier to identify the differences between three groups of participants in pairwise comparisons: controls, people with ASC and their unaffected siblings. Then we compared those differences selecting spatially collocated as candidate endophenotypes of ASC. [less ▲]

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See detailESTUDIO ANTE Y POST-MORTEM DE LAS CARACTERÍSTICAS FISIOPATOLÓGICAS DEL TRACTO GENITAL Y SUS FACTORES DE RIESGO EN VACAS LECHERAS EN EL SUR DE VIETNAM
Nguyen, Kien Cuong; Tomas Mulet, Cristina; Okouyi-Mfoumou, Marcel et al

Conference (2014, June)

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See detailColloque International "La Géographie Physique et les Risques Naturels" - Livre de résumés
Ozer, André ULg; Ozer, Pierre ULg

Book published by Université de Liège (2014)

Lors du Congrès de l’Association Internationale des Géomorphologues (AIG-IAG) qui s’est tenu à Paris en août 2013, plusieurs collègues ont demandé d’organiser à Liège le colloque inaugural de ... [more ▼]

Lors du Congrès de l’Association Internationale des Géomorphologues (AIG-IAG) qui s’est tenu à Paris en août 2013, plusieurs collègues ont demandé d’organiser à Liège le colloque inaugural de l’Association Francophone de Géographie Physique (AFGP). Profitant du ‘17th Joint Geomorphological Meeting’ déjà prévu du 30 juin au 3 juillet 2014 regroupant des géomorphologues de Belgique, France, Italie, Roumanie et Grèce, il a été proposé de nous réunir à Liège les 29 et 30 juin en prélude à cette réunion pour ‘lancer’ l’Association Francophone de Géographie Physique. Nous avons ainsi pu regrouper des amis francophones provenant de nombreux pays et réunis autour de la thématique du rôle de la géographie physique dans la gestion des risques naturels. Ce thème est cher à l’Université de Liège qui coordonne, depuis 2000, un Master complémentaire en Gestion des Risques Naturels ouvert aux pays francophones. Ce document présente les résumés des 27 communications scientifiques qui y seront présentées lors de ce Colloque intitulé "La Géographie Physique et les Risques Naturels". [less ▲]

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