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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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See detailBrussels IIbis Regulation - an appraisal of the application in Belgium
Wautelet, Patrick ULg

Report (2014)

This report, commissioned by the European Commission, undertakes to map out the practice of Belgian courts and authorities in relation to the Brussels IIbis Regulation (Regulation 2201/2003). It is based ... [more ▼]

This report, commissioned by the European Commission, undertakes to map out the practice of Belgian courts and authorities in relation to the Brussels IIbis Regulation (Regulation 2201/2003). It is based on a questionnaire submitted to experts in all Member States in the framework of a study on the assessment of the Regulation (EC) No 2201/2003 and the policy options for its amendment (call for tenders No JUST/2012/JCIV/FW/0195/A4). The purpose of this backward-looking evaluation is to assess the practical application and the effects of Regulation (EC) No 2201/2003 in terms of its relevance, coherence, effectiveness, efficiency, and EU added value and utility. [less ▲]

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See detailMembrane interactions of cyclic lipodepsipeptides from the viscosin group
Geudens, Niels; Feher, Krisztina; De Vleeschouwer et al

Poster (2014, June)

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See detailApplication of hyperspectral Raman imaging to the analysis of a self-emulsifying drug delivery system (SEDDS).
Sacre, Pierre-Yves ULg; De Bleye, Charlotte ULg; Netchacovitch, Lauranne ULg et al

Poster (2014, June)

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of ... [more ▼]

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of poorly water-soluble drugs. The API is finely dispersed in the excipients and forms a solid solution increasing its dissolution rate. Hyperspectral Raman imaging is a powerful tool that combines both spectral and spatial information. It returns qualitative and quantitative information useful during the development or the characterization of pharmaceutical preparations. The studied formulation consisted of a BCS 2 API (high permeability, low solubility) dispersed in excipients mainly composed of Lauroyl macrogol-32 glycerides (>50%). Two different preparations were analyzed: 100% of API dissolved and 70% of API dissolved with 30% of API powder added to the formulation. The two formulations have therefore exactly the same qualitative and quantitative composition but different spatial distribution and dispersion of the API mimicking a problem during the process. First a confocal Raman microscopic analysis was performed to evaluate the solid state of the API in the formulations. Then, an evaluation of the particle size was performed. These results are important since they can affect the bioavailability of the API and therefore its activity. Beside the microscopic scale analysis, a macroscopic imaging quantitative PLS model has been developed. The method has been validated within +/- 10% acceptance limits following the total error approach. This validated quantitative model enables reliable quantitative analysis at the pixel level of Raman images providing meaningful chemical images. [less ▲]

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See detailMulti-scale aquifer characterization and groundwater flow model parameterization using direct push technologies
Rogiers, Bart; Vienken, Thomas; Gedeon, Matej et al

in Environmental Earth Sciences (2014)

Direct push (DP) technologies are typically used for cost-effective geotechnical characterization of unconsolidated soils and sediments. In more recent developments, DP technologies have been used for ... [more ▼]

Direct push (DP) technologies are typically used for cost-effective geotechnical characterization of unconsolidated soils and sediments. In more recent developments, DP technologies have been used for efficient hydraulic conductivity (K) characterization along vertical profiles with sampling resolutions of up to a few centimetres. Until date, however, only a limited number of studies document high-resolution in situ DP data for three-dimensional conceptual hydrogeological model development and groundwater flow model parameterization. This study demonstrates how DP technologies improve building of a conceptual hydrogeological model. We further evaluate the degree to which the DP-derived hydrogeological parameter K, measured across different spatial scales, improves performance of a regional groundwater flow model. The study area covers an area of ~60 km² with two overlying, mainly unconsolidated sand, aquifers separated by a 5-7 m thick highly heterogeneous clay layer (in north-eastern Belgium). The hydrostratigraphy was obtained from an analysis of cored boreholes and about 265 cone penetration tests (CPTs). The hydrogeological parameter K was derived from a combined analysis of core and CPT data and also from hydraulic direct push tests. A total of 50 three-dimensional realizations of K were generated using a non-stationary multivariate geostatistical approach. To preserve the measured K values in the stochastic realizations, the groundwater model Krealizations were conditioned on the borehole and direct push data. Optimization was performed to select the best performing model parameterization out of the 50 realizations. This model outperformed a previously developed reference model with homogeneous K fields for all hydrogeological layers. Comparison of particle tracking simulations, based either on the optimal heterogeneous or reference homogeneous groundwater model flow fields, demonstrate the impact DP-derived subsurface heterogeneity in K can have on groundwater flow and solute transport. We demonstrated that DP technologies, especially when calibrated with site-specific data, provide high-resolution 3D subsurface data for building more reliable conceptual models and increasing groundwater flow model performance. [less ▲]

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See detailLe B.I.M et la maquette virtuelle comme moyen pédagogique permettant le rapprochement entre les cours d'informatique et l'enseignement du projet d'architecture
Boutemadja, Abdelkader ULg; Driesmans, Carine ULg; Jancart, Sylvie ULg

in Kubicki, Sylvain; Halin, Gilles; Bignon, Jean-Claude (Eds.) Scan 14 sémainaire de conception architecturale numérique : Interaction(s) des maquettes numériques (2014, June)

In the context of this paper, we pose the question of the conditions of possible link between computer courses and design projet. The integration of schools of architecture at universities is an ... [more ▼]

In the context of this paper, we pose the question of the conditions of possible link between computer courses and design projet. The integration of schools of architecture at universities is an opportunity to focus in the experiments made in this direction and to propose to implement the terms of this rapprochement. For us, it is important that this approach lies in the Bachelor years in a common core for all students. [less ▲]

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See detailDistributed Model-free Control of Photovoltaic Units for Mitigating Overvoltages in Low-Voltage Networks
Aristidou, Petros ULg; Olivier, Frédéric ULg; Hervas, Maria Emilia et al

in Proc. of CIRED 2014 workshop (2014, June)

In this paper, a distributed model-free control scheme to mitigate overvoltage problems caused by high photovoltaic generation in low-voltage feeders is proposed. The distributed controllers are ... [more ▼]

In this paper, a distributed model-free control scheme to mitigate overvoltage problems caused by high photovoltaic generation in low-voltage feeders is proposed. The distributed controllers are implemented on the photovoltaic inverters and modulate the active and reactive power injected into the network. In particular, they direct photovoltaic units first to consume reactive power and, if necessary, curtail active power generation to reduce high voltages in the feeder. [less ▲]

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See detailMODEL PREDICTIVE CONTROL OF CONGESTION AND VOLTAGE PROBLEMS IN ACTIVE DISTRIBUTION NETWORKS
Soleimani Bidgoli, Hamid ULg; Glavic, Mevludin ULg; Van Cutsem, Thierry ULg

in Proc. of CIRED Workshop 2014 (2014, June)

This paper presents a centralized control scheme, inspired of Model Predictive Control (MPC), to manage thermal overloads and correct abnormal voltages in real-time. The control scheme is able to smoothly ... [more ▼]

This paper presents a centralized control scheme, inspired of Model Predictive Control (MPC), to manage thermal overloads and correct abnormal voltages in real-time. The control scheme is able to smoothly bring the system within the desired limits, taking into account its near-future evolution. The control method effectiveness is illustrated on a 20-kV, 32-bus network hosting four distributed generation units. [less ▲]

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See detailThe two scenarios for quantum multifractality breakdown
Georgeot, Bertrand; Dubertrand, Rémy; Garcia-Mata, Ignacio et al

Scientific conference (2014, June)

Several types of physical systems are characterized by quantum wave func- tions with multifractal properties. In the quantum chaos field, they cor- respond to pseudointegrable systems, with properties ... [more ▼]

Several types of physical systems are characterized by quantum wave func- tions with multifractal properties. In the quantum chaos field, they cor- respond to pseudointegrable systems, with properties intermediate between integrability and chaos. In condensed matter, they include electrons in a disordered potential at the Anderson metal-insulator transition. This multi- fractality leads to particular transport properties and appears in conjunction with specific types of spectral statistics. In parallel, progress in experimental techniques allows to observe finer and finer properties of the wavefunctions of quantum or wave systems, as well as to perform experiments with un- precedented control on the dynamics of the systems studied. In this context, this talk will discuss the robustness of multifractality in presence of footnote- size perturbations. We expose two scenarios for the breakdown of quantum multifractality under the effect of such perturbations. In the first scenario, multifractality survives below a certain scale of the quantum fluctuations. In the other one, the fluctuations of the wave functions are changed at every scale and each multifractal dimension smoothly goes to the ergodic value. We use as generic examples a one-dimensional dynamical system and the three- dimensional Anderson model at the metal-insulator transition, and show that for different types of perturbation the destruction of multifractal properties always follows one of these two ways. Our results thus suggest that quantum multifractality breakdown is universal and obeys one of these two scenarios depending on the perturbation. We also discuss the experimental implica- tions. [less ▲]

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