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See detailCan any possible combination of modes improve intermodal attractiveness?
Mostert, Martine ULg; Caris, An; Limbourg, Sabine ULg

in Proceedings of the BIVEC-GIBET Transport Research Days 2017 (2017, May)

In its White Paper on Transport, the European Commission recognizes intermodal transport as an alternative solution to road transport. In practice, intermodal transport can be constituted by any ... [more ▼]

In its White Paper on Transport, the European Commission recognizes intermodal transport as an alternative solution to road transport. In practice, intermodal transport can be constituted by any combination of modes, while in the literature, intermodal transport is often modeled as a combination of modes in the order “road-rail/inland waterway-road”. This work develops a new intermodal allocation model which allows choosing between any direct (road, rail and inland waterways) transport and any intermodal transport chain constituted by up to three modes of transport. Intermodal solutions can pass through one or two intermodal terminals. Applied on experimental data at the European level, the model gives insight on the optimal flow distribution for economic objectives (optimization of transport operational costs) and environmental objectives (optimization of transport CO2 emissions and air pollution external costs). Results highlight that the traditional modeling of intermodal transport as a “road-rail/inland waterway-road” combination better fits economic than environmental objectives. [less ▲]

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See detailNon-Invasive Analysis of Mural Painting from a Late-Republican House (1st century B.C.) in Ostia
Strivay, David ULg; Herens, Elodie ULg; Morard, Thomas ULg et al

Conference (2017, May)

This paper is a comprehensive analytical study of the murals belonging to an ancient Roman house through the characterization of materials. The project focuses on the wall paintings of the Domus dei ... [more ▼]

This paper is a comprehensive analytical study of the murals belonging to an ancient Roman house through the characterization of materials. The project focuses on the wall paintings of the Domus dei bucranes, a house of the end of the Republican era discovered on the site of the Schola of Trajan in Ostia. This Domus has undergone several phases of development in the 1st century BC before being destroyed around 20 BC. A new house was immediately rebuilt after a major change from the ground, which allowed exceptional preservation of the decoration system. The results complement our knowledge of Roman painting techniques during the 1st century BC and also provide a comprehensive multidisciplinary approach to the problem of conservation of wall paintings. These two related objectives have been studied using non-destructive testing methods (MA-XRF, FTIR and Raman spectroscopy). The analyzes have been performed in situ using our mobile systems. The different set-ups had to be modified in order to be able to work on horizontal surfaces, specially our XRF scanner. The study of the pictorial layers address various issues in the field of archaeology: what technique has been implemented? Does the same technique was used in both phases of the development of Domus? Do they correspond to the techniques described by ancient writers? These responses are compared to those observed in other sets of murals dating from the 1st century BC. [less ▲]

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See detailUltrasonic roll bite measurements in cold rolling: Contact length and strip thickness
Carretta, Yves; Hunter, Andrew; Boman, Romain ULg et al

in Proceedings of the Institution of Mechanical Engineers - Part J - Journal of Engineering Tribology (2017)

In cold rolling of thin metal strip, contact conditions between the work rolls and the strip are of great importance: roll deformations and their effect on strip thickness variation may lead to strip ... [more ▼]

In cold rolling of thin metal strip, contact conditions between the work rolls and the strip are of great importance: roll deformations and their effect on strip thickness variation may lead to strip flatness defects and thickness inhomogeneity. To control the process, online process measurements are usually carried out; such as the rolling load, forward slip and strip tensions at each stand. Shape defects of the strip are usually evaluated after the last stand of a rolling mill thanks to a flatness measuring roll. However, none of these measurements is made within the roll bite itself due to the harsh conditions taking place in that area. This paper presents a sensor capable of monitoring strip thickness variations as well as roll bite length in situ and in real time. The sensor emits ultrasonic pulses that reflect from the interface between the roll and the strip. Both the time-of-flight of the pulses and the reflection coefficient (the ratio of the amplitude of the reflected signal to that of the incident signal) are recorded. The sensor system was incorporated into a work roll and tested on a pilot rolling mill. Measurements were taken as steel strips were rolled under several lubrication conditions. Strip thickness variation and roll-bite length obtained from the experimental data agree well with numerical results computed with a cold rolling model in the mixed lubrication regime. [less ▲]

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See detailEtude expérimentale et numérique d'un échangeur destiné à la récupération de chaleur fatale sur bancs d'essais de moteurs aéronautiques
Gendebien, Samuel ULg; Guillaume, Ludovic ULg; Bellolio Domke, Sebastian Andres ULg et al

in Colloque Inter-universitaire Franco-Québécois (CIFQ 2017), 22-24 mai 2017, Saint-Lô, France (2017, May)

Aujourd’hui, d’importants efforts sont réalisés dans divers secteurs afin de diminuer la consommation en énergie. En ce qui concerne le secteur aéronautique, de nombreux tests sont réalisés sur les ... [more ▼]

Aujourd’hui, d’importants efforts sont réalisés dans divers secteurs afin de diminuer la consommation en énergie. En ce qui concerne le secteur aéronautique, de nombreux tests sont réalisés sur les moteurs afin d’assurer la sécurité du transport aérien. Dans ce contexte, il a été envisagé de récupérer, recycler et valoriser l’énergie produite par le moteur au moyen d’un échangeur placé dans la cheminée d’évacuation des gaz. Pour ce faire, un prototype de modèle réduit d’échangeur récupératif sur gaz de combustion (gaz/eau ou gaz/huile) a été conçu, fabriqué et testé. Ce papier présente les caractéristiques du modèle réduit de l’échangeur développé spécifiquement pour cette application. L’ensemble du banc d’essais et le système de mesure mis en place afin de caractériser les performances de l’échangeur sont décrits. Une analyse des résultats expérimentaux est présentée. Les tests sont notamment divisés en deux parties : établissement des performances en régime monophasique et diphasique. Notons également que les performances hydrauliques de l’échangeur ont été expérimentalement déterminées. Un modèle numérique de type semi-empirique est proposé pour prédire les performances de l’échangeur. Ce dernier nécessite un calibrage des paramètres au moyen des données expérimentales afin de prédire les performances de l’échangeur sous une grande plage de conditions opératoires. Une comparaison entre résultats numériques et expérimentaux est finalement présentée. [less ▲]

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See detailMODELISATION D’UN ECHANGEUR A THERMOSIPHONS POUR LA RECUPERATION DE CHALEUR
Le, Van Long ULg; Dumas, Xavier; Ferrand, Ludovic et al

in XIIIème Colloque Interuniversitaire Franco-Québécois sur la Thermique des Systèmes (2017, May)

Le présent travail a pour objectif de modéliser un échangeur à thermosiphons diphasiques pour transporter la chaleur d’un effluent gazeux (c.à.d. gaz de combustion) à haute température (720°C) au système ... [more ▼]

Le présent travail a pour objectif de modéliser un échangeur à thermosiphons diphasiques pour transporter la chaleur d’un effluent gazeux (c.à.d. gaz de combustion) à haute température (720°C) au système ORC (cycle organique de Rankine). Les thermosiphons sont placés dans les gaz de combustion et refroidis par le fluide de travail du système ORC (le Cyclopentane pour le cas actuel). Le débit massique des fumées et la puissance thermique de l’échangeur sont respectivement imposés de 21 kg/s et de 4.022 MWth. Le fluide organique s’évapore à une température de 200°C et quitte l’évaporateur sans surchauffe (vapeur saturée). Le modèle de simulation développé dans le logiciel EES (Engineering Equation Solver) est capable de déterminer le nombre nécessaiare de thermosiphons. L’influence des pas transversaux et longitudinaux de l’échangeur sur le nombre de thermosiphons et la perte de charge des fumées est également examinée pour les dispositions quinconces et alignées des tubes de thermosiphons. [less ▲]

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See detailSustainability Accounting and Control for Smart City - Special Issue - Call for Papers
Crutzen, Nathalie ULg; Van Bockhaven, Jonas; Schaltegger, Stefan et al

in sustainability accounting, management and policy journal (2017)

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See detailOrigin of the counterintuitive dynamic charge in the transition metal dichalcogenides
Pike, Nicholas ULg; Van Troeye, Benoit; Dewandre, Antoine ULg et al

in Physical Review B (2017), 95

Despite numerous studies of transition metal dichalcogenides, the diversity of their chemical bonding characteristics and charge transfer is not well understood. Based on density functional theory we ... [more ▼]

Despite numerous studies of transition metal dichalcogenides, the diversity of their chemical bonding characteristics and charge transfer is not well understood. Based on density functional theory we investigate their static and dynamic charges. The dynamic charge of the transition metal dichalcogenides with trigonal symmetry are anomalously large, while in their hexagonally symmetric counterparts, we even observe a counterintuitive sign, i.e., the transition metal takes a negative charge, opposite to its static charge. This phenomenon, so far never remarked on or analyzed, is understood by investigating the perturbative response of the system and by investigating the hybridization of the molecular orbitals near the Fermi level. Furthermore, a link is established between the sign of the Born effective charge and the process of π backbonding from organic chemistry. Experiments are proposed to verify the calculated sign of the dynamical charge in these materials. Employing a high-throughput search we also identify other materials that present counterintuitive dynamic charges. [less ▲]

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See detailLes épreuves multiples chez les jeunes. Réflexion sur un programme développemental à long terme.
Jidovtseff, Boris ULg

Learning material (2017)

Réflexion personnelle sur une proposition de modèle développemental à long terme spécifique aux épreuves multiples en athlétisme.

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See detailRégimes matrimoniaux et effets patrimoniaux des partenariats enregistrés en Europe. Propos introductifs
Wautelet, Patrick ULg

in Droit de la famille (2017), 22(5), 10-13

Ce bref texte présente quelques propos introductifs destinés à situer les règlements 2016/1103 et 2016/1104. Le texte s'attarde sur l'histoire de ces règlements, leur plus-value et esquisse certaines des ... [more ▼]

Ce bref texte présente quelques propos introductifs destinés à situer les règlements 2016/1103 et 2016/1104. Le texte s'attarde sur l'histoire de ces règlements, leur plus-value et esquisse certaines des questions ouvertes qu'ils posent [less ▲]

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See detailMartian mesospheric cloud observations by IUVSon MAVEN: Thermal tides coupled to the upper atmosphere
Stevens; Siskind; Evans et al

in Geophysical Research Letters (2017), 44

The manuscript describes the observation of Martian mesosphericclouds between 60 and 80 km altitude by the Imaging Ultraviolet Spectrograph (IUVS) on NASA’sMAVEN spacecraft. The cloud observations are ... [more ▼]

The manuscript describes the observation of Martian mesosphericclouds between 60 and 80 km altitude by the Imaging Ultraviolet Spectrograph (IUVS) on NASA’sMAVEN spacecraft. The cloud observations are uniquely obtained at early morning local times, whichcomplement previous observations obtained primarily later in the diurnal cycle. Differences in thegeographic distribution of the clouds from IUVS observations indicate that the local time is crucial for theinterpretation of mesospheric cloud formation. We also report concurrent observations of upperatmospheric scale heights near 170 km altitude, which are diagnostic of temperature. These observationssuggest that the dynamics enabling the formation of mesospheric clouds propagate all the way to theupper atmosphere. [less ▲]

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See detailTranscriptome wide analysis of natural antisense transcripts shows potential role in breast cancer
Wenric, Stéphane ULg; El Guendi, Sonia; CABERG, Jean-Hubert ULg et al

Poster (2017, May)

Non-coding RNAs (ncRNA) represent at least 1/5 of the mammalian transcript amount, and about 90% of the genome length is actively transcribed. Many ncRNAs have been demonstrated to play a role in cancer ... [more ▼]

Non-coding RNAs (ncRNA) represent at least 1/5 of the mammalian transcript amount, and about 90% of the genome length is actively transcribed. Many ncRNAs have been demonstrated to play a role in cancer. Among them, natural antisense transcripts (NAT) are RNA sequences which are complementary and overlapping to those of protein-coding transcripts (PCT). NATs were punctually described as regulating gene expression, and are expected to act more frequently in cis than other ncRNAs that commonly function in trans. In this work, 22 breast cancers expressing estrogen receptors and their paired healthy tissues were analyzed by strand-specific RNA sequencing. To highlight the potential role of NATs in gene regulations occurring in breast cancer, three different gene extraction methods were used: differential expression analysis of NATs between tumor and healthy tissues, differential correlation analysis of paired NAT/PCT between tumor and healthy tissues, and NAT/PCT read count ratio variation between tumor and healthy tissues. Each of these methods yielded lists of NAT/PCT pairs that were demonstrated to be enriched in survival-associated genes on an independent cohort (TCGA). This work allows to highlight NAT lists that display a strong potential to affect the expression of genes involved in the breast cancer pathology. [less ▲]

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See detailDeciphering the role of dendritic sodium channels on action potential dynamics in substantia nigra dopaminergic neurons
Moubarak, Estelle; Engel, Dominique ULg; Dufour, Martial et al

Poster (2017, May)

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See detailAdvanced method optimization for volatile aroma profiling of beer using two-dimensional gas chromatography time-of-flight mass spectrometry
Stefanuto, Pierre-Hugues ULg; Perrault, Katelynn ULg; Dubois, Lena ULg et al

in Journal of Chromatography. A (2017)

The complex mixture of volatile organic compounds (VOCs) present in the headspace of Trappist and craft beers was studied to illustrate the efficiency of thermal desorption (TD) comprehensive two ... [more ▼]

The complex mixture of volatile organic compounds (VOCs) present in the headspace of Trappist and craft beers was studied to illustrate the efficiency of thermal desorption (TD) comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS) for highlighting subtle differences between highly complex mixtures of VOCs. Headspace solid-phase microextraction (HS-SPME), multiple (and classical) stir bar sorptive extraction (mSBSE), static headspace (SHS), and dynamic headspace (DHS) were compared for the extraction of a set of 21 representative flavor compounds of beer aroma. A Box-Behnken surface response methodology experimental design optimization (DOE) was used for convex hull calculation (Delaunay’s triangulation algorithms) of peak dispersion in the chromatographic space. The predicted value of 0.5 for the ratio between the convex hull and the available space was 10% higher than the experimental value, demonstrating the usefulness of the approach to improve optimization of the GC × GC separation. Chemical variations amongst aligned chromatograms were studied by means of Fisher Ratio (FR) determination and F‐distribution threshold filtration at different significance levels (α = 0.05 and 0.01) and based on z‐score normalized area for data reduction. Statistically significant compounds were highlighted following principal component analysis (PCA) and hierarchical cluster analysis (HCA). The dendrogram structure not only provided clear visual information about similarities between products but also permitted direct identification of the chemicals and their relative weight in clustering. The effective coupling of DHS-TD-GC × GC-TOFMS with PCA and HCA was able to highlight the differences and common typical VOC patterns among 24 samples of different Trappist and selected Canadian craft beers. [less ▲]

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See detailDiscovery and pharmacological characterization of succinate receptor (SUCNR1/GPR91) agonists
Geubelle, Pierre ULg; Gilissen, Julie; Dilly, Sebastien et al

in British Journal of Pharmacology (2017), 174(9), 796-808

Background and Purpose The succinate receptor (SUCNR1 or GPR91) has been described as a metabolic sensor that may be involved in homeostasis. Notwithstanding its implication in important (patho ... [more ▼]

Background and Purpose The succinate receptor (SUCNR1 or GPR91) has been described as a metabolic sensor that may be involved in homeostasis. Notwithstanding its implication in important (patho)physiological processes, the function of SUCNR1 has remained elusive because no pharmacological tools were available. We report on the discovery of the first family of synthetic potent agonists. Experimental Approach We screened a library of succinate analogues and analysed their activity on SUCNR1. In addition, we modelled a pharmacophore and a binding site for the receptor. New agonists were identified based on the information provided by these two approaches. Their activity was studied in various bioassays, including measurement of cAMP levels, [Ca2+]i mobilisation, TGF-α shedding and recruitment of arrestin 3. The in vivo impact of SUCNR1 activation by these new agonists was evaluated on rat blood pressure. Key Results We identified cis-epoxysuccinic acid and cis-1,2-cyclopropanedicarboxylic acid as agonists with an efficacy similar to the one of succinic acid. Interestingly, cis-epoxysuccinic acid was characterized by a 10 to 20 fold higher potency than succinate on the receptor. For example, cis-epoxysuccinic acid reduced cAMP levels with a pEC50 = 5.57 ± 0.02 (EC50 = 2.7 μM) as compared to succinate pEC50 = 4.54 ± 0.08 (EC50 = 29 μM). The rank order of potency of the three agonists was the same in all bioassays tested. In vivo, cis-epoxysuccinic and cis-1,2-cyclopropanedicarboxylic acid increased rat blood pressure to the same extent as succinate did. Conclusions and Implications We provide new agonist tools for SUCNR1 that should facilitate further research on this understudied receptor. [less ▲]

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See detailInfluence qualitative et quantitative du mode de séchage sur l'huile essentielle de Thymus fontanesii de l'Algérie
Sidali, Lamia; Brada, Moussa; Fauconnier, Marie-Laure ULg et al

Poster (2017, May)

Cette étude a pour but d`étudier l`influence du mode de séchage (à l’ombre et au soleil) sur le rendement et la composition chimique de l`huile essentielle de Thymus fontanesii de l`Algérie obtenue par ... [more ▼]

Cette étude a pour but d`étudier l`influence du mode de séchage (à l’ombre et au soleil) sur le rendement et la composition chimique de l`huile essentielle de Thymus fontanesii de l`Algérie obtenue par extraction assistée par induction électromagnétique. Les résultats ont montré que le séchage à l`ombre a donné un meilleur rendement de (1.12%) après une période de séchage de 10 jours jusqu`à la stabilisation de teneur en eau, alors que le séchage au soleil pendant 8 jours donne un rendement de (0.89%). La composition chimique de l`huile essentielle de Thymus fontanesii (TF) a été analysé par la chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC/MS) et la chromatographie en phase gazeuse a ionisation de flamme (GC/FID). [less ▲]

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See detailIntroduction aux doctrines et aux idées politiques: une approche structurale
Claisse, Frédéric ULg; Counet, Maxime ULg; Verjans, Pierre ULg

Book published by De Boeck Supérieur (2017)

Comment s’articulent les grandes doctrines et idées politiques ? En quoi des auteurs comme Machiavel ou La Boétie peuvent-ils nous aider à comprendre l’exercice du pouvoir et la résistance à la domination ... [more ▼]

Comment s’articulent les grandes doctrines et idées politiques ? En quoi des auteurs comme Machiavel ou La Boétie peuvent-ils nous aider à comprendre l’exercice du pouvoir et la résistance à la domination ? Quels sont les clivages qui constituent la toile de fond de la vie politique ? De Bodin à Maurras et Renan, de Condorcet à Sen, de Montesquieu à Hayek et de Marx à Rawls et Piketty, en passant par Hobbes, Locke et Bossuet, les grands auteurs ont apporté des réponses à quatre questions fondamentales auxquelles toute société se trouve confrontée : Qui sommes-nous ? Pourquoi vivons-nous ensemble ? Comment produisons-nous ? Comment distribuons-nous nos richesses ? Ces réponses continuent d’influencer en profondeur les débats politiques. Plutôt que de présenter les doctrines politiques en familles idéologiques homogènes (libéralisme, socialisme, conservatisme), cet ouvrage met en évidence les unités de base qui sous-tendent les principaux énoncés politiques, quelle que soit l’étiquette sous laquelle ils circulent. Fruit de nombreuses années d’analyse et d’enseignement, ce manuel offre un point de vue original sur les doctrines et idées politiques, à travers une approche structurale qui insiste sur les jeux d’oppositions et de priorités, tout en passant en revue des œuvres fondatrices de notre imaginaire politique. Pour les étudiants, qui trouveront dans cet ouvrage une introduction aux doctrines et idées politiques, ainsi qu’une approche analytique des grands auteurs. Pour les citoyens, à qui il fournira des ressources pour mieux s’orienter parmi les positionnements politiques et en comprendre la logique. [less ▲]

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