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See detailImpact of shading on meiofauna in a Posidonia oceanica meadow
Pete, Dorothée ULg; Gobert, Sylvie ULg

Poster (2014, December)

Posidonia oceanica meadow is an endemic ecosystem of the Mediterranean coasts. A known threat to this ecosystem is aquaculture. In zones of intensive fish production, P. oceanica meadow tends to be less ... [more ▼]

Posidonia oceanica meadow is an endemic ecosystem of the Mediterranean coasts. A known threat to this ecosystem is aquaculture. In zones of intensive fish production, P. oceanica meadow tends to be less healthy or to disappear .One of the reasons for this is a decrease in the light that reaches the leaves (direct shading, increase of water turbidity or of epiphytic algae density). Unfortunately, when the meadow begins to die, it is often too late to act. So, people are trying to find indicators that react early to this kind of perturbations. In this framework, this study focuses on the impact of shading (without nutrient enrichment) on the meiofauna living in the surface sediment of a P. oceanica meadow. An in situ shading experiment was led from the end of May to the end of August 2009, at a depth of 10 m, in a reference P. oceanica meadow. Three shading nets were put in the meadow to reach a light extinction of 50%. A control site was also defined. The first two centimetres of sampled sediment cores were studied. After three months of shading, the total abundance of meiofauna at the shading site was lower than at the beginning of the experiment, while it stayed around the same level at the control site. This difference is mainly due to a decrease in the total number of foraminiferans, nematods, gnathostomulids, copepods and bivalves. However, no significant difference in diversity was observed. At the end of this experiment, it appeared that, contrarily to what is mostly said in the literature, the direct organic enrichment that occurs at fish farms is not the only reason to the modification of the meiofauna communities of the ecosystem. The shading by itself has also an effect. [less ▲]

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See detailLettre d'information du projet Dacefi-Synthèse & réalisations majeures
Meunier, Quentin; Morin, Amélie; Moumbougou, Carl et al

E-print/Working paper (2014)

Cette dernière lettre d'information du projet présente le bilan de ses réalisations et les avancées importantes du Gabon en termes de foresterie communautaire

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See detailEvaluation of pairwise calibration techniques for range cameras and their ability to detect a misalignment
Lejeune, Antoine ULg; Grogna, David ULg; Van Droogenbroeck, Marc ULg et al

in International Conference on 3D Imaging (IC3D) (2014, December)

Many applications require the use of multiple cameras to cover a larger volume. In this paper, we evaluate several pair-wise calibration techniques dedicated to range cameras. We compare the precision of ... [more ▼]

Many applications require the use of multiple cameras to cover a larger volume. In this paper, we evaluate several pair-wise calibration techniques dedicated to range cameras. We compare the precision of a self-calibration technique based on the movement in front of the cameras to object based calibration. While the self-calibration method is less precise than its counterparts, it yields a first estimation of the transformation between the cameras and permits to detect when the cameras become mis-aligned. Therefore it is useful in a practical situations. [less ▲]

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See detailProjet DACEFI 2. Atlas cartographique. Présentation des outils d'analyse spatiale et d'aide à la décision.
Morin, Amélie; Meunier, Quentin; Federspiel, Michèle et al

Cartographic material (2014)

Faisant suite à une première phase (2006-2008), le projet pilote Développement d’Alternatives Communautaires à l’Exploitation Forestière Illégale (DACEFI-2, de 2010 à 2014) s’est employé à tester au Gabon ... [more ▼]

Faisant suite à une première phase (2006-2008), le projet pilote Développement d’Alternatives Communautaires à l’Exploitation Forestière Illégale (DACEFI-2, de 2010 à 2014) s’est employé à tester au Gabon la mise en oeuvre des forêts communautaires, promues par le code forestier gabonais en 2001 (loi n°016/01). Pour cela, le projet a appuyé les communautés rurales désireuses de gérer elles-mêmes une portion de forêt et les a accompagnées tout au long du processus de création d’une forêt communautaire. Ce processus, adapté dans la mesure du possible aux communautés rurales, est jalonné de multiples étapes et peut paraitre parfois long et fastidieux. Présentant des méthodologies d’action et des cartes, cet atlas a été développé à la fin des 5 années d’exécution dans l’idée de capitaliser la démarche adoptée par le projet pour aboutir à la délimitation d’une forêt communautaire. Il vient également synthétiser pour le lecteur les travaux cartographiques réalisés dans les villages et regroupements de villages, que le projet a appuyés tout au long de sa mise en oeuvre. Par ailleurs, la loi indique qu’une « forêt communautaire est une portion du Domaine Forestier Rural (DFR) affectée à une communauté villageoise ». Dans le contexte local, lors du projet DACEFI-2, l’absence de définition précise du DFR a poussé l’équipe à mener une étude complémentaire pour déterminer l’espace nécessaire et l’espace disponible pour la mise en place de forêts communautaires. Cet atlas est donc également l’occasion de présenter cette synthèse. [less ▲]

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See detailExplaining the CMS Higgs lepton-flavor violating
Aristizabal Sierra, Diego ULg; Vicente, Avelino ULg

in Physical Review. D : Particles and Fields (2014), 90(11), 115004

Direct searches for lepton flavor violating Higgs boson decays in the τ μ channel have been recently reported by the CMS collaboration. The results display a slight excess of signal events with a ... [more ▼]

Direct searches for lepton flavor violating Higgs boson decays in the τ μ channel have been recently reported by the CMS collaboration. The results display a slight excess of signal events with a significance of 2.5σ, which translates into a branching ratio of about 1%. By interpreting these findings as a hint for beyond the standard model physics, we show that the Type-III 2HDM is capable of reproducing such signal while at the same time satisfying vacuum stability, perturbativity, electroweak precision data, measured Higgs standard decay modes and low-energy lepton flavor violating constraints. We have found that the allowed signal strength ranges for the bb, WW* and ZZ* standard channels shrink as soon as BR(h→τμ)∼ 1% is enforced. Thus, we point out that if the excess persists, improved measurements of these channels may be used to test our Type-III 2HDM scenario. [less ▲]

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See detailEcology of 20 trace elements in Mytilus galloprovincialis
Richir, Jonathan ULg; Lepoint, Gilles ULg; Lejeune, Pierre et al

Conference (2014, December)

Trace elements (TEs) are considered as non-degradable pollutants. This persistent character can alter their natural biogeochemical balance in contaminated environments. TEs are further toxic for aquatic ... [more ▼]

Trace elements (TEs) are considered as non-degradable pollutants. This persistent character can alter their natural biogeochemical balance in contaminated environments. TEs are further toxic for aquatic organisms from threshold levels and are thus likely to cause multiple damages to the population, the community and the ecosystem levels. For these reasons, their environmental occurrence has to be accurately monitored. The main interest of the use of quantitative sentinel organisms to this end, or bioindicator species, is their capacity to give information on the bioavailability of environmental contaminants. Mussels from the genus Mytilus are particularly well suited organisms for the monitoring of the coastal contamination. Native wild and cultured Mytilus galloprovincialis Lamarck, 1819 have been widely used since around 40 years to this purpose along coasts of the eastern Atlantic and the Mediterranean. But the accurate use of a bioindicator relies on the detailed knowledge of its ecophysiology and the influence of environmental variables on the bioaccumulation processes. In the framework of the STARECAPMED project, the ecology of 20 TEs in M. galloprovincialis is therefore investigated. The mussel morphometry and biology firstly define the TE accumulation processes. Accumulated TE are internally regulated and redistributed between body compartments; these internal processes notably depend on the essential or non-essential character of TEs. As filter feeder, mussels accumulate soluble and suspended TEs whose environmental levels are determined by the geomorphology, the physico-chemistry and the hydrology of monitored coastal meadows. All these factors are acting together to modulate the TE accumulation processes in mussels. TE bioaccumulated levels further balance quickly when any physiological or environmental changes occur in order to reach a new steady-state with environmental TE loads. The ecology of TEs in M. galloprovincialis is thus complex and very dynamic; these considerations must be taken into account when monitoring the chemical contamination of coastal meadows. [less ▲]

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See detailActive network management for electrical distribution systems: problem formulation and benchmark
Gemine, Quentin ULg

Scientific conference (2014, November 28)

In order to operate an electrical distribution network in a secure and cost-efficient way, it is necessary, due to the rise of renewable energy-based distributed generation, to develop Active Network ... [more ▼]

In order to operate an electrical distribution network in a secure and cost-efficient way, it is necessary, due to the rise of renewable energy-based distributed generation, to develop Active Network Management (ANM) strategies. These strategies rely on short-term policies that control the power injected by generators and/or taken of by loads in order to avoid congestion or voltage problems. While simple ANM strategies would curtail the production of generators, more advanced ones would move the consumption of loads to relevant time periods to maximize the potential of renewable energy sources. However, such advanced strategies imply solving large-scale optimal sequential decision-making problems under uncertainty, something that is understandably complicated. In order to promote the development of computational techniques for active network management, we detail a generic procedure for formulating ANM decision problems as Markov decision processes. We also specify it to a 75-bus distribution network. The resulting test instance is available at http://www.montefiore.ulg.ac.be/~anm/ . It can be used as a test bed for comparing existing computational techniques, as well as for developing new ones. A solution technique that consists in an approximate multistage program is also illustrated on the test instance. [less ▲]

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See detailQuels modèles pour soutenir la prévention et la promotion de la santé ?
Vanmeerbeek, Marc ULg; Mathonet, Julien; Miermans, Marie-Christine ULg et al

Conference (2014, November 28)

Contexte et objectifs La prévention n’atteint pas souvent son objectif d’accès universel aux soins préventifs. Les modèles opérationnels publiés concernant la prévention et la promotion de la santé en ... [more ▼]

Contexte et objectifs La prévention n’atteint pas souvent son objectif d’accès universel aux soins préventifs. Les modèles opérationnels publiés concernant la prévention et la promotion de la santé en soins primaires ont été recherchés pour réaliser un inventaire fonctionnel et formuler des hypothèses de travail sur l’efficacité et l’équité de la prévention. Méthode Revue narrative de littérature utilisant les mots-clés relatifs aux différents niveaux de prévention, à la promotion de la santé, aux soins primaires, aux modèles de pratique et à la délivrance de soins. Une analyse multicritères a été utilisée. Principaux résultats Douze modèles ont été sélectionnés. Les modèles dont les auteurs annoncent qu’ils s’appliquent à la prévention décrivent majoritairement des approches centrées sur les individus dans le cadre de la relation médecin-patient, prenant en compte l’organisation de pratique. Certains modèles systémiques de type socio-écologique illustrent le concept de promotion de la santé : pratique éducative, ciblage sur des groupes ou des populations, prise en compte des milieux de vie et des déterminants sociaux de la santé. La place des patients dans l’élaboration des modèles est mineure, à l’image de leur implication comme acteurs dans les systèmes de soins. Les définitions des termes de prévention, promotion de la santé et éducation du patient diffèrent considérablement d’un modèle à l’autre. Discussion et conclusion Certains éléments valorisés par la promotion de la santé seraient intégrables aux pratiques de soins : empowerment individuel des patients, prise en compte de leurs milieux de vie ; participation accrue à des réseaux locaux de professionnels de la santé ; intégration, au sein des mêmes structures, de l’approche individuelle et collective pour permettre la poursuite simultanée des objectifs de personnalisation, d’efficacité et d’équité. Ces évolutions ont des implications sur la formation des soignants, en termes d’aptitudes communicationnelles, de sensibilisation aux concepts de la santé publique et d’immersion précoce des futurs soignants dans la communauté. [less ▲]

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See detailEstimating Ventricular Stroke Work from Aortic Pressure Waveform
Kamoi, Shun; Pretty, Christopher; Chiew, Yeong Shiong et al

in 13th Belgian Day on Biomedical Engineering (2014, November 28)

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See detailEstimating Ventricular Stroke Work from Aortic Pressure Waveform
Kamoi, Shun; Pretty, Christopher; Chiew, Yeong Shiong et al

Poster (2014, November 28)

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See detailTracking stressed blood volume during vascular filling experiments
Pironet, Antoine ULg; Dauby, Pierre ULg; Chase, J. Geoffrey et al

Poster (2014, November 28)

A three-chamber cardiovascular system model is used to compute stressed blood volume from filling experiments. As previously observed, stressed blood volume is a good predictor of the change in cardiac ... [more ▼]

A three-chamber cardiovascular system model is used to compute stressed blood volume from filling experiments. As previously observed, stressed blood volume is a good predictor of the change in cardiac output after fluid infusion. [less ▲]

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See detailTracking stressed blood volume during vascular filling experiments
Pironet, Antoine ULg; Dauby, Pierre ULg; Chase, J. Geoffrey et al

in 13th Belgian Day on Biomedical Engineering (2014, November 28)

A three-chamber cardiovascular system model is used to compute stressed blood volume from filling experiments. As previously observed, stressed blood volume is a good predictor of the change in cardiac ... [more ▼]

A three-chamber cardiovascular system model is used to compute stressed blood volume from filling experiments. As previously observed, stressed blood volume is a good predictor of the change in cardiac output after fluid infusion. [less ▲]

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See detailL’animation théâtrale comme présence sociale
Brahy, Rachel ULg

Conference (2014, November 27)

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See detailClimat et gaz à effet de serre: récentes évolutions constatées
Ozer, Pierre ULg

Scientific conference (2014, November 26)

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See detailHigh-throughput synthesis of functional oxide films
Dhanapal, Pravarthana ULg

Doctoral thesis (2014)

Epitaxy of metal oxides is of great interest since it provides a way to obtain desired novel properties for the applications such as electronics and energy. However, earlier epitaxy research's have been ... [more ▼]

Epitaxy of metal oxides is of great interest since it provides a way to obtain desired novel properties for the applications such as electronics and energy. However, earlier epitaxy research's have been restricted because of the limited range of compositions and low-index of commercially available single crystal substrates. Consequently, novel epitaxy synthesis methods need to be developed in order to go beyond the present demands of of single crystal substrates in terms of phase, composition, size, orientation and symmetry. In this research work, we have developed a high-throughput synthesis process, called combinatorial substrate epitaxy (CSE), where an oxide film is grown epitaxially on a polycrystalline substrate. As a proof-of-concept, we firstly fabricated Ca3Co4O9 films on Al2O3 ceramics. Films have a good local epitaxial registry, and the Seebeck coefficient is about 170 µV/K at 300 K. High quality BiFeO3/La0.7Sr0.3MnO3 thin film heterostructures were secondly deposited on dense LaAlO3 ceramics prepared by spark plasma sintering. Piezoforce microscopy was used to confirm the local ferroelectric properties. Thirdly, we investigate the growth of of metastable monoclinic Dy2Ti2O7 epitaxial films on polycrystalline La2Ti2O7 substrates. We conclude that CSE approach opens the way towards unexpected electronic properties in oxide films. [less ▲]

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See detailPattern Matching & Image Registration
Latour, Philippe ULg

Learning material (2014)

This document is an overwiew of the objectives, methods and applications of pattern matching and image registration. Both pixel-based and features-based methods are reviewed and compared. Some ... [more ▼]

This document is an overwiew of the objectives, methods and applications of pattern matching and image registration. Both pixel-based and features-based methods are reviewed and compared. Some applications to machine vision (electronic component manufacturing) are described. [less ▲]

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See detailDroit constitutionnel belge - Plan général du cours (année 2014-2015)
Behrendt, Christian ULg

Learning material (2014)

Le document constitue le Plan général de l'enseignement de Droit constitutionnel dispensé à l'Université de Liège en 2e année de bachelier en droit et en 2e année de bachelier en science politique.

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See detailUse of 13C-NMR in structural elucidation of polysaccharides: case of locust bean gum
Gillet, Sébastien ULg; Aguedo, Mario ULg; Blecker, Christophe ULg et al

Poster (2014, November 25)

Locust bean gum (LBG) galactomannans are polysaccharides consisting of a β-(1→4) D-mannopyranosyl backbone substituted to varying degrees in α-(1→6) with single D-galactopyranosyl residues. This basic ... [more ▼]

Locust bean gum (LBG) galactomannans are polysaccharides consisting of a β-(1→4) D-mannopyranosyl backbone substituted to varying degrees in α-(1→6) with single D-galactopyranosyl residues. This basic structure is the same for all galactomannans (Fig. 2). However, when locust bean gum is extracted at different temperatures, the generated fractions exhibit different properties in aqueous solution (viscosity, viscoelasticity, gel formation, thermohydrolysis resistance, etc.). This means that there are differences within the fine structure of the polymers (although the basic structure is the same). Analysis of [13C]-NMR spectra of galactomannans, in combination with other techniques, can provide capital information about fine structural elucidation of the polymers. The method specifies the distribution of lateral galactosyls along the main chain of mannans. Two fractions extracted from locust bean gum at 25 and 80 °C (respectively GM25 and GM80) were comparatively studied by [13C]-NMR. Mannosyls/Galactosyls (M/G) ratios can be determined by considering the intensities of C-1 mannose and galactose signals in [13C]-NMR spectra. This method provides results relatively close to those obtained by GC-MS analysis. Spectra also showed that resonance from C4 of D-mannose residues were split, in evident dependence upon the nearest-neighbor probabilities (“diad frequencies”) of D-galactosyl groups along the mannan chains (Fig. 2). Diad frequencies were obtained by integrating C4(Man) peak areas. F11, F21/F12 and F22 gave respectively the di-, mono- or non-substituted mannose pairs proportions. High percentages of F11 and F22 therefore indicate a more non-homogeneous distribution of lateral galactosyls along the polysaccharide backbone as observed for GM80. The percentages of total lateral substituents obtained by C4(Man) peak analysis [F11 + (F21 or F12)/2] were fairly well correlated with M/G ratios. Splitting of the C-6 substituted D-mannose resonance provides, therefore the basis for determining the next-nearest-neighbor probabilities (triad frequencies) (Fig. 2). However, the spectrum is often not sufficiently resolved to accurately quantify and interpret the results. [less ▲]

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