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

in Metabolic Brain Disease (in press)

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

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

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See detailLes animateurs de la vie littéraire en Belgique francophone : de leur rôle interne à leur position de médiateur transnational
Dozo, Björn-Olav ULg

in Blanchard, Nelly; Thomas, Mannaig (Eds.) Des littératures périphériques (in press)

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See detailMemory Reactivation During Rapid Eye Movement (REM) Sleep Promotes Its Generalization and Integration in Cortical Stores
Sterpenich, Virginie; Schmidt, Christina ULg; Albouy, Genevièvre et al

in Sleep (in press)

Memory reactivation appears to be a fundamental process in memory consolidation. Here, we tested the influence of memory reactivation during REM sleep on memory performance and brain responses at ... [more ▼]

Memory reactivation appears to be a fundamental process in memory consolidation. Here, we tested the influence of memory reactivation during REM sleep on memory performance and brain responses at retrieval in healthy human participants. Auditory cues were associated with pictures of faces during their encoding. These memory cues delivered during REM sleep enhanced subsequent accurate recollections but also false recognitions. These results suggest that reactivated memories interacted with semantically-related representations, and induced new creative associations, which subsequently reduced the distinction between new and previously encoded exemplars. Cues had no effect if presented during stage 2 sleep, or if they were not associated with faces during encoding. Functional MRI revealed that following exposure to conditioned cues during REM sleep, responses to faces during retrieval were enhanced both in a visual area and in a cortical region of multisensory (auditory-visual) convergence. These results show that reactivating memories during REM sleep enhances cortical responses during retrieval, suggesting the integration of recent memories within cortical circuits, favoring the generalization and schematization of the information. [less ▲]

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See detailA generic anisotropic continuum damage model integration scheme adaptable to both ductile damage and biological damage-like situations
Mengoni, Marlène ULg; Ponthot, Jean-Philippe ULg

in International Journal of Plasticity (in press)

This paper aims at presenting a general versatile time integration scheme applicable to anisotropic damage coupled to elastoplasticity, considering any damage rate and isotropic hardening formulations ... [more ▼]

This paper aims at presenting a general versatile time integration scheme applicable to anisotropic damage coupled to elastoplasticity, considering any damage rate and isotropic hardening formulations. For this purpose a staggered time integration scheme in a finite strain framework is presented, together with an analytical consistent tangent operator. The only restrictive hypothesis is to work with an undamaged isotropic material, assumed here to follow a J2 plasticity model. The only anisotropy considered is thus a damage-induced anisotropy. The possibility to couple any damage rate law with the present algorithm is illustrated with a classical ductile damage model for aluminium, and a biological damage-like application. The later proposes an original bone remodelling law coupled to trabecular bone plasticity for the simulation of orthodontic tooth movements. All the developments have been considered in the framework of the implicit non-linear finite element code Metafor (developed at the LTAS/MN2L, University of Liège, Belgium - www.metafor.ltas.ulg.ac.be). [less ▲]

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See detailEnjeux autour des forêts congolaises
Vermeulen, Cédric ULg

in Cahiers africains (in press)

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

in Histoires littéraires (in press)

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

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See detailAn enhanced version of a bone remodelling model based on the continuum damage mechanics theory.
Mengoni, Marlène ULg; Ponthot, Jean-Philippe ULg

in Computer Methods in Biomechanics & Biomedical Engineering (in press)

The purpose of this work is to propose an enhancement of Doblaré and García's internal bone remodelling model based on the continuum damage mechanics theory. In their paper, they stated that the evolution ... [more ▼]

The purpose of this work is to propose an enhancement of Doblaré and García's internal bone remodelling model based on the continuum damage mechanics theory. In their paper, they stated that the evolution of the internal variables of the bone microstructure, and its incidence on the modification of the elastic constitutive parameters, may be formulated following the principles of Continuum Damage Mechanics, although no actual damage was considered. The resorption and apposition criteria (similar to the damage criterion) were expressed in terms of a mechanical stimulus. However, the resorption criterion is lacking a dimensional consistency with the remodelling rate. We here propose an enhancement to this resorption criterion, insuring the dimensional consistency while retaining the physical properties of the original remodelling model. We then analyse the change in the resorption criterion hypersurface in the stress space for a 2D analysis. We finally apply the new formulation to analyse the structural evolution of a 2D femur. This analysis gives results consistent with the original model but with a faster and more stable convergence rate. [less ▲]

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See detailImpact of vocal load on breathiness: Perceptual evaluation
Remacle, Angélique ULg; Schoentgen, Jean; FINCK, Camille ULg et al

in Logopedics, Phoniatrics, Vocology (in press)

Objectives: To evaluate the impact on voice of 2 hours of continuous oral reading. Methods: Fifty normophonic women underwent two sessions of voice loading in which the required intensity level varied: 60 ... [more ▼]

Objectives: To evaluate the impact on voice of 2 hours of continuous oral reading. Methods: Fifty normophonic women underwent two sessions of voice loading in which the required intensity level varied: 60-65 dB(A) for the first session, and 70-75 dB(A) for the second session. Ten expert judges evaluated the breathiness of one sentence recorded before and after each loading session. Pairs of stimuli were presented randomly to the judges, who were asked to designate the breathiest sample. Results: A significant decrease in breathiness was observed following both sessions, suggesting an improvement of voice subsequent to loading. When comparing the two intensity levels, no difference was found for breathiness after vocal loading. [less ▲]

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See detailVALORISATION DES RESIDUS DE BOIS ISSUS DE L’EXPLOITATION ARTISANALE DES FORETS COMMUNAUTAIRES AU CAMEROUN : CAS DE LA FORET COMMUNAUTAIRE DE MAMBIOKO (GIC CRVC)
Malnoury, Gauthier; Zoyiem Ngouanet, Edmond; Julve Larrubia, Cecilia et al

in Tropicultura (in press)

L’exploitation artisanale du bois des forêts communautaires au Cameroun génère une quantité importante de résidus abandonnés au niveau des sites d’exploitation. Ces pièces de bois pourraient être ... [more ▼]

L’exploitation artisanale du bois des forêts communautaires au Cameroun génère une quantité importante de résidus abandonnés au niveau des sites d’exploitation. Ces pièces de bois pourraient être valorisées en produits commercialisables de manière à améliorer les revenus de la communauté. Cette étude a permis une première estimation de ce volume et présente différentes pistes de valorisation adaptées à la communauté de Mambioko. Cette étude de cas s’adresse à tous les acteurs de la foresterie communautaire au Cameroun et vise une valorisation rationnelle de la matière ligneuse dans un but de développement rural. [less ▲]

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See detail"Cachez cette erreur que je ne saurais voir ! " - Représentations et Attitudes normatives chez des enseignants et apprenants de français langue étrangère
Defays, Jean-Marc ULg; Meunier, Deborah ULg

in Rosier, Laurence (Ed.) Actes du colloque international « Si j’aurais su, j’aurais pas venu! - linguistique des formes exclues : descriptions, genres, épistémologie » (in press)

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See detailA Balance Equation Determines a Switch in Neuronal Excitability
Franci, Alessio ULg; Drion, Guillaume ULg; Seutin, Vincent ULg et al

in PLoS Computational Biology (in press)

We use the qualitative insight of a planar neuronal phase portrait to detect an excitability switch in arbitrary conductance-based models from a simple mathematical condition. The condition expresses a ... [more ▼]

We use the qualitative insight of a planar neuronal phase portrait to detect an excitability switch in arbitrary conductance-based models from a simple mathematical condition. The condition expresses a balance between ion channels that provide a negative feedback at resting potential (restorative channels) and those that provide a positive feedback at resting potential (regenerative channels). Geometrically, the condition imposes a transcritical bifurcation that rules the switch of excitability through the variation of a single physiological parameter. Our analysis of six di erent published conductance based models always nds the transcritical bifurcation and the associated switch in excitability, which suggests that the mathematical predictions have a physiological rel- evance and that a same regulatory mechanism is potentially involved in the excitability and signaling of many neurons. [less ▲]

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See detailData processing of vibrational chemical imaging for pharmaceutical applications.
Sacre, Pierre-Yves ULg; De Bleye, Charlotte ULg; Chavez, Pierre-François ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (in press)

Vibrational spectroscopy (MIR, NIR and Raman) based hyperspectral imaging is one of the most powerful tools analyze pharmaceutical preparation. Indeed, it combines the advantages of vibrational ... [more ▼]

Vibrational spectroscopy (MIR, NIR and Raman) based hyperspectral imaging is one of the most powerful tools analyze pharmaceutical preparation. Indeed, it combines the advantages of vibrational spectroscopy to imaging techniques and allows therefore the visualization of distribution of compounds, crystallization processes. However, these techniques provide a huge amount of data that must be processed to extract the relevant information. This review presents fundamental concepts of hyperspectral imaging, the basic theory of the most used chemometric tools used to pre-process, process and post-process the generated data. The last part of the present paper focuses on pharmaceutical applications of hyperspectral imaging and highlights the data processing approaches to enable the reader making the best choice among the different tools available. [less ▲]

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See detailLe rôle de la perception de soi comme lecteur dans le développement de la compétence en lecture
Schillings, Patricia ULg; Dupont, Virginie; Neuberg, France ULg et al

in Mesure et Evaluation en Education [=MEE] (in press)

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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 (in press)

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 detailAlgorithmic and Computational Advances for Fast Power System Dynamic Simulations
Aristidou, Petros ULg; Van Cutsem, Thierry ULg

in Proceedings of the IEEE PES General Meeting (in press)

In this paper, some algorithmic and computational advances are presented for power system dynamic simulations. The heart is a Schur-complement-based solution algorithm, stemming from domain decomposition ... [more ▼]

In this paper, some algorithmic and computational advances are presented for power system dynamic simulations. The heart is a Schur-complement-based solution algorithm, stemming from domain decomposition methods, applied to the differential-algebraic equation model. This algorithm is then accelerated computationally, by employing parallel computing techniques, and numerically, by exploiting time-scale decomposition and localization. Models of a real medium-scale system and a realistic large-scale test system are used for the performance evaluation of the proposed methods. [less ▲]

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See detailOn the convergence of relaxation schemes to couple phasor-mode and electromagnetic transients simulations
Plumier, Frédéric ULg; Geuzaine, Christophe ULg; Van Cutsem, Thierry ULg

in Proceedings of the IEEE PES General Meeting (in press)

Hybrid simulations combining phasor-mode and electromagnetic transients models aim at taking advantage of computational speed of the former and accuracy of the latter. For simulation accuracy, a ... [more ▼]

Hybrid simulations combining phasor-mode and electromagnetic transients models aim at taking advantage of computational speed of the former and accuracy of the latter. For simulation accuracy, a relaxation process is used, which consists of iterating between both models. The convergence properties of this relaxation process are investigated. The speed of convergence is assessed when the variables exchanged at the interface between both models are respectively pure voltage/current sources, Norton/Thévenin equivalents, or a combination of them. Iteratively updated Norton/Thévenin equivalents are shown to drastically reduce the number of relaxation iterations. [less ▲]

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See detailMobilité et apprentissage linguistique : des représentations contrastées ?
Meunier, Deborah ULg

in Yasri-Labrique, Eleonore; Gardies, Patricia; Djordevic, Ksenija (Eds.) Didactique contrastive: questionnements et applications (in press)

Detailed reference viewed: 18 (1 ULg)