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See detailLa Paix de Fexhe : un texte, des acteurs
Masson, Christophe ULg

Conference (2016, September 15)

La Paix de Fexhe fut le résultat d’un compromis entre les cinq différents « partis » politiques liégeois de l’époque : le prince-évêque, le chapitre cathédral de Saint-Lambert, le « patriciat » urbain, la ... [more ▼]

La Paix de Fexhe fut le résultat d’un compromis entre les cinq différents « partis » politiques liégeois de l’époque : le prince-évêque, le chapitre cathédral de Saint-Lambert, le « patriciat » urbain, la noblesse et les artisans. Nous étudierons donc dans le cadre de cette contribution l’identité de ces partis, ainsi que celles des délégués qu’ils envoyèrent à Fexhe, leur « agenda politique » et leurs moyens d’action. Nous reviendrons ensuite sur la part que chacun prit à la rédaction du texte du 18 juin 1316 et de ses deux compléments ratifiés le même jour et le lendemain, ce qui nous permettra de mesurer la place que chacun put faire tenir à ses revendications, nuançant, pour le moins, la lecture « démocratique » ou « ecclésio-paternaliste » en cours depuis le xixe siècle. De façon complémentaire, nous mettrons en évidence les champs d’application et les limites de ces textes, en les articulant avec ceux qui les précédèrent afin de mieux en percevoir les implications sur la longue durée de l’histoire liégeoise. [less ▲]

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See detailIntroduction
Masson, Christophe ULg

Conference (2016, September 15)

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See detailTHERMO-ECONOMIC OPTIMIZATION OF ORGANIC RANKINE CYCLE SYSTEMS FOR WASTE HEAT RECOVERY FROM EXHAUST AND RECIRCULATED GASES OF HEAVY DUTY TRUCKS
Guillaume, Ludovic ULg; Legros, Arnaud; Lemort, Vincent ULg

Conference (2016, September 14)

Waste heat recovery (WHR) ORC is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks (HDT). Nonetheless, the adoption of this ... [more ▼]

Waste heat recovery (WHR) ORC is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks (HDT). Nonetheless, the adoption of this technology in the automotive domain requires specific R&D activities going from the system definition to the on-board integration. This study focuses on the preliminary design phase of ORC systems recovering the heat wasted from two of the sources available on a HDT: the exhaust and recirculated gases. From these heat sources and their combinations, 6 possible architectures are identified. On the other hand, 4 volumetric expansion machine technologies are considered (Scroll, Screw, Piston and Vane Expanders). At the end, 24 topologies are modelled considering only the main components (Pump, Heat exchangers, Expansion machines). A three-step optimization method is proposed to identify the most promising system. First, the most suitable design conditions are identified using a simple model of expansion machine. In a second step, the design phase, using more detailed models for the expansion machines, a thermodynamic and economic optimizations are performed. Finally, in a third step, the output power of the latter system models is maximized in off-design conditions. [less ▲]

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See detailAssessment of vertical contamination of Cd, Pb and Zn in soils around a former ore smelter in Wallonia, Belgium
Liénard, Amandine ULg; Colinet, Gilles ULg

Conference (2016, September 14)

Examples of sites contaminated by atmospheric fallouts are numerous across former industrial areas, among which the valleys of Sambre and Meuse in Wallonia hosted metal ore treatment factories. We have ... [more ▼]

Examples of sites contaminated by atmospheric fallouts are numerous across former industrial areas, among which the valleys of Sambre and Meuse in Wallonia hosted metal ore treatment factories. We have studied the fate of Cd, Pb and Zn in soils affected by atmospheric deposition in the vicinity of old smelters. The importance of vertical redistribution of contaminants in soils is questioned and the aims of this paper are to i) characterize the vertical distribution of TEs and soil properties along diverse soil profiles, ii) evaluate enrichment or impoverishment of TEs along the profiles to discriminate anthropogenic or geogenic origin of contaminations and iii) evaluate whether soil type or land use influenced the mobility of contaminants in the selected profiles. Concentrations of trace elements (Cd, Co, Cr, Cu, Ni, Pb, and Zn) and major elements (Ca, Mg, K, Fe, Al, and Mn) as well as pHKCl and TOC were measured on 22 profiles located in a 3 km radius of a former ore treatment plant in Wallonia (Belgium). Enrichment factor (EF), vertical impoverishment factor (VIF), and availability ratio (AR) were used as diagnostic tools of contamination and migration of Cd, Pb, and Zn in profiles. Data revealed that soil profiles are significantly contaminated. The ranges of enrichment factors for Cd (17-3570), Pb (1-2883), and Zn (2-309) are very broad with the higher EF in the topsoil of profile. VIFs of subhorizons are rarely above 1. In a few remaining cases with VIF > 1, the main factor explaining is soil type (especially, Colluvic Regosols, Luvisols, and, Cambisols with shale load). Cd, Pb and Zn ARs are strongly correlated with TOC and to a lesser extent with pHKCl. Pb and Zn ARs are influenced by soil type and land use only plays on Zn AR. The Cd availability is independent by these two factors. The contents of trace elements measured in soil profiles are very high especially in topsoil. Until now, the Cd, Pb, and Zn vertical distribution shows a low migration from topsoil up to depth. However, we must not minimize the hazard of a future potential transfer. [less ▲]

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See detailDYNAMIC MODELING OF WASTE HEAT RECOVERY ORGANIC RANKINE CYCLE SYSTEMS IN THE AMESIM PLATFROM
Guillaume, Ludovic ULg; Ameel, Bernd; Criens, Chris et al

Conference (2016, September 14)

ORC waste heat recovery is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks. Because of the transient nature of the heat sources ... [more ▼]

ORC waste heat recovery is a very promising technology for reducing fuel consumption and consequently the CO2 emissions of future heavy-duty trucks. Because of the transient nature of the heat sources encountered on a truck, dynamic simulations are an essential part of the design process of ORC systems for truck applications. Dynamic models are useful for component design, control design and transient evaluation of ORC systems. To ease the burden of building numerous dynamic models of different candidate ORCs while the design process is ongoing, a library of generic dynamic models of ORCs is built in this work. These models work in synergy with a steady-state ORC design tool in which is added a function to automatically populate the parameters of the dynamic models. In this work, the dynamic model library and their parameterization process in LMS AMESim are described. The platform is largely used in automotive industry and offers a variety of libraries: Engine, Control, Two-Phase Flow, etc. Finally, the dynamic models are compared against the steady-state models and experimental data. [less ▲]

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See detailIs Ambrosia artemisiifolia L. able to expand its invaded range northward in Western Europe?
Ortmans, William ULg; Mahy, Grégory ULg; Monty, Arnaud ULg

Conference (2016, September 13)

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of ... [more ▼]

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of central and southern France, and northern Italy. Northwards beyond the edge of this range, occurrence of casual population have been described for years, but these populations do not appear to become invasive, and the species does not seem to spread. This situation raises the following question: Has the invaded range reached a limit or will the species continue its invasion northwards? To answer this question, we followed two complementary approaches. First we set up an experimental garden in Belgium, 250 km north to the current invaded range, to see if the local climate allows the completion of the species reproduction cycle. Second, we performed an in situ measurement campaign in 12 population located beyond the edge, within the range but near the margin, and in the center of the invaded range. The aim of this campaign was to test whether the species had reduced plant performance towards range margins. The results showed that the species is able to establish populations with high growth rates in Belgium. Furthermore, the species expressed similar performance across the considered areas, even beyond the current invasion front. No evidence of processes constraining the invasion was found, which suggests a great potential for invasion north to the current invaded range. In this uncertain situation, awareness actions should be considered in the northern countries. [less ▲]

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See detailOrganocatalytic ring-opening polymerization towards polyphosphoesters
Clément, Benoit; Vanslambrouck, Stépanie; Carion, Stéphan ULg et al

Conference (2016, September 13)

Hydrolytically degradable and biocompatible aliphatic polyesters are widely applied for biomedical applications as implants, scaffolds for tissue engineering and, finally, as nanocarriers for drug ... [more ▼]

Hydrolytically degradable and biocompatible aliphatic polyesters are widely applied for biomedical applications as implants, scaffolds for tissue engineering and, finally, as nanocarriers for drug delivery. Aliphatic phophoesters, known since the pioneering work of S. Penczek in the 70’s, exhibit the same properties of hydrolytic degradability and biocompatibility and are thus more and more studied for biomedical applications as well. In the field of materials, anti-fire properties opens up new perspectives. The difference between polyesters and polyphosphoesters in terms of synthesis and properties will be highlighted. Polyphosphosphoesters are synthesized by step-growth and chain growth polymerization. When these polyphosphoesters are synthesized by ring-opening polymerization of cyclic phosphoesters, organocatalysts turned out to be very efficient compared to coodination processes. The last part of the talk will deal with te implementation of ROP of cyclic phosphates towards a series of amphiphilic PEO-block-polyphosphate copolymers of tailored hydrophobicity depending on the length of the lateral alkyl group. These polymers are able to self assemble into nanoparticles by direct dissolution in water, thus in the absernce of any organic solvent. The so-obtained micelles were studied by a set of techniques (Pyrene Fluorescence, Dynamic Light Scattering, Tensiometry). Finally, the influence of the hydrophobicity of the polyphosphate block of the micelle on the encapsulation and the release of a model drug was investigated. [less ▲]

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See detailModelling the mortality of Hylotrupes bajulus (L.) larvae exposed to anoxic treatment for disinfestation of wooden art objects
de Streel, Géraud; Henin, Jean-Marc; Bogaert, Patrick et al

Conference (2016, September 13)

Experiments were conducted to quantify the effect of several variables on the mortality of insects exposed to an anoxic treatment in order to generate a model linking mortality to these variables. This ... [more ▼]

Experiments were conducted to quantify the effect of several variables on the mortality of insects exposed to an anoxic treatment in order to generate a model linking mortality to these variables. This study aims to explore the possible interest of using such a model to determine the characteristics of treatment (especially duration) needed to guarantee insect mortality with a given level of probability. Trials were performed on Hylotrupes bajulus larvae, which is a widespread species known for its high tolerance to anoxic conditions. The studied variables are the initial mass of the larvae, the treatment temperature (21, 30 and 40 °C), the treatment duration (four durations for each temperature tested) and whether the larva is held in wood or in a petri dish (directly exposed to anoxic atmosphere) during the experiment. It was found that, while the last variable is not correlated with mortality, treatment duration and temperature are significantly and positively correlated with it. Larvae with higher body mass were also shown to have a better resistance to the treatment. Based on these results, a model including insect initial mass, treatment temperature and duration, together with the interaction between these two variables, was determined. This relatively simple model appeared to be a useful tool in overcoming the difficulty in defining the modalities for anoxic treatment in order to reach a given level of mortality. [less ▲]

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See detailInvestigating the effect of plant-derived amendments on PAHs degradation in brownfield contaminated soils
Davin, Marie ULg; Starren, Amandine ULg; Colinet, Gilles ULg et al

Conference (2016, September 13)

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistant organic compounds of major concern that tend to accumulate in the environment, damaging ecosystems and health. Brownfields represent an ... [more ▼]

Polycyclic aromatic hydrocarbons (PAHs) are a class of persistant organic compounds of major concern that tend to accumulate in the environment, damaging ecosystems and health. Brownfields represent an important tank for PAHs that require remediation. As an alternative to environmentally aggressive, expensive and often disruptive soil remediation strategies, experiences have been carried on to understand and develop techniques based on bioremediation and phytoremediation. PAHs degradation experiments were conducted in microcosms (laboratory scale) in order to determine whether several plant-derived amendments could enhance bioremediation. Briefly, samples of aged contaminated soils were treated with different concentrations of Medicago sativa or Trifolium pratense root exudates or dried roots, commercial saponin, a natural surfactant found in some plant roots such as some Fabaceae, and some samples were left unamended as controls. Soil samples were incubated for two and four weeks at controlled temperature (28°C). Carbon dioxide emission was monitored throughout the whole incubation. At the end of each experiment, dehydrogenase activity was measured as an indicator of microbiological activity and residual PAHs were determined using High-Performance Liquid Chromatography with Fluorimetric Detection (HPLC-FLD). In total, eleven amendment modalities and two incubation periods were tested and repeated four times. Preliminary experiments show promising results as amended samples seem to show different respiration activities. Ongoing studies will allow discussion as to whether or not PAHs degradation is influenced by the different modalities and if there are any differences according to the nature and concentration of the amendment. [less ▲]

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See detailOverhanging Constraints in Addivitive Manufacturing Using Two Different Tools
Bauduin, Simon ULg; Collet, Maxime ULg; Duysinx, Pierre ULg

Conference (2016, September 12)

Topology optimization is widely used as a design tool for advanced application in mechanical, aerospace and automotive industries. This technique offers an optimal distribution of a predetermined amount ... [more ▼]

Topology optimization is widely used as a design tool for advanced application in mechanical, aerospace and automotive industries. This technique offers an optimal distribution of a predetermined amount of material in a given design space. In the last years, a lot of efforts has been invested into the development of high performance methods such as homogenization, SIMP or BESO. However as the state of the art in manufacturing experiences evolution, a coupling between topology optimization and additive manufacturing is needed. Additive manufacturing has numerous advantages that fits the characteristics of topology optimized designs. It can manufacture highly complex design without high cost increase and furthermore continuous density material of the SIMP method could be manufactured by lattice structures. With all the opportunities given by the additive manufacturing the urge to bind the last one to topology optimization is heavily required. Specific constraints related to manufacturing issues have to be taken into account such as the need of supports structures to ensure a good heat evacuation during the manufacturing process, as well as to hold up overhanging section. Some researches have been done to try to include this constraint in the optimization problem such as Leary and al or Andrew T. Gaynor. However this work focuses on 2 different methods (projection scheme and mechanical approach) to tackle the overhanging problem and compare them . [less ▲]

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See detailJoint learning and pruning of decision forests
Begon, Jean-Michel ULg; Joly, Arnaud ULg; Geurts, Pierre ULg

Conference (2016, September 12)

Decision forests such as Random Forests and Extremely randomized trees are state-of-the-art supervised learning methods. Unfortunately, they tend to consume much memory space. In this work, we propose an ... [more ▼]

Decision forests such as Random Forests and Extremely randomized trees are state-of-the-art supervised learning methods. Unfortunately, they tend to consume much memory space. In this work, we propose an alternative algorithm to derive decision forests under heavy memory constraints. We show that under such constraints our method usually outperforms simpler baselines and can even sometimes beat the original forest. [less ▲]

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See detailRandom subspace with trees for feature selection under memory constraints
Sutera, Antonio ULg; Châtel, Célia; Louppe, Gilles et al

Conference (2016, September 12)

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See detailInfluence of grain boundaries on the COads monolayer oxidation and oxygen reduction reaction kinetics
Asset, Tristan ULg; Chattot, Raphaël; Nelayah, Jaysen et al

Conference (2016, September 12)

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See detailMicrostructural design using stress–based topology optimization
Collet, Maxime ULg; Bruggi, Matteo; Noël, Lise ULg et al

Conference (2016, September 12)

New additive manufacturing techniques break the limitations encountered for years when producing components descending from topology optimization. Classical design procedures focus on macro-structural ... [more ▼]

New additive manufacturing techniques break the limitations encountered for years when producing components descending from topology optimization. Classical design procedures focus on macro-structural optimization to sustain given loads but today innovative manufacturing processes allow considering structures exhibiting tailored microstructures, i.e. the well known microstructural design. The practical applications of structures including material design is mainly motivated by the greater performances that can be achieved compared to classical solutions. Microstructural design has been shown a great interest as attested by recent works. However, stress–based topology optimization has not yet been extensively exploited when addressing microstructural design using numerical homogenization though stress constraints is an important feature and have gained in interest in the field of topology optimization. This contribution investigates the problem of material design enforcing stress constraints within periodic microstructures by considering a representative volume element (RVE) subject to prescribed strain fields. The SIMP approach is adopted as material interpolation law while the optimization problems are solved using a sequential convex programming approach. In particular the well known method of moving asymptotes (MMA) is considered. Numerical homogenization is used to assess the effective elastic properties of the microstructures. The Von Mises stress criterion is used to impose the constraints on the stress level. This work discusses the formulation of a well-posed design problem as well as some numerical issues encountered. The developed solution procedure is first validated by comparison against analytical results, e.g. the single inclusion of Vigdergauz microstructure. [less ▲]

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See detailLinkages and production and marketing of rice vermicelli in traditional craft villages of Bac Giang province
Le Thy Long, Vy; Nguyen Huu, Nhuan; Lebailly, Philippe ULg

Conference (2016, September 10)

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See detailImplications de la perspective en première personne en psychopathologie : le cas de la schizophrénie
Englebert, Jérôme ULg; Valentiny, Caroline

Conference (2016, September 09)

Les approches traditionnelles de la schizophrénie en psychiatrie se centrent essentiellement sur une perspective que l’on peut qualifier de perspective en « troisième personne ». Ces considérations ... [more ▼]

Les approches traditionnelles de la schizophrénie en psychiatrie se centrent essentiellement sur une perspective que l’on peut qualifier de perspective en « troisième personne ». Ces considérations tentent, de l’extérieur, de circonscrire les difficultés auxquelles sont confrontées les personnes affectées d’une psychopathologie. Dans le cas de la schizophrénie, les manuels insistent notamment sur les symptômes délirants et hallucinatoires – signes sur lesquels, de facto, le clinicien et le patient ne peuvent s’entendre et rencontrer une phénoménologie commune. Une autre voie d’approche, s’inscrivant dans la tradition phénoménologique, propose d’explorer les phénomènes à partir du discours et du vécu subjectif des patients – dans une perspective en « première personne ». À partir d’une recherche récemment menée, nous explorerons le vécu subjectif de six patients schizophrènes à l’aide de l’échelle EASE (Examination of Anomalous Self-Experience). Cette échelle pose des balises dans la co-construction d’une narrativité permettant l’investigation d’expériences liées aux troubles du soi. Ce choix méthodologique s’ancre dans une volonté de laisser la place à l’étonnement, de ne pas pré-penser, ou le moins possible, le recueil d’expériences. Les analyses des phénomènes décrits par les patients se nourrissent des travaux de la psychopathologie phénoménologique (Blankenburg, Minkowski, Tatossian, Stanghellini, Sass, …) et se veulent un aller-retour constant entre théorie et clinique. Dans ce contexte, nous approfondirons l’hypothèse proposée par Louis Sass selon laquelle la folie, du moins dans certaines de ses formes, pourrait dériver d’une intensification plutôt que d’un affaiblissement de la conscience. L’hyper-réflexivité schizophrénique – indiquant une focalisation explicite et réflexive sur des phénomènes a priori implicites et préréflexifs – sera particulièrement analysée à partir des descriptions recueillies. Après avoir développé, à partir des cas cliniques, cette hypothèse d’une « hyper-conscience » comme symptôme cardinal de l’expérience subjective de la schizophrénie, nous analyserons les implications du recours à la perspective en « première personne » sur la prise en charge, les modèles de soins et la manière de concevoir le rapport au monde de ces patients. [less ▲]

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See detailSeroprevalence of Borrelia burgdorferi in horses in the southern part of Belgium: a “one health” driven study
Meersschaert, Carole; Cerri, Simona ULg; Houben rosa, Rosa et al

Conference (2016, September 08)

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See detailUnified treatment of microscopic boundary conditions in computational homogenization method for multiphysics problems
Nguyen, Van Dung ULg; Wu, Ling ULg; Homsi, Lina ULg et al

Conference (2016, September 08)

Computational homogenization (so-called FE2) method is an effective tool to model complex behavior of heterogeneous media allowing direct coupling between the structure response and the evolving ... [more ▼]

Computational homogenization (so-called FE2) method is an effective tool to model complex behavior of heterogeneous media allowing direct coupling between the structure response and the evolving microstructure not only in purely mechanical problems but also in multiphysics problems [1]. The basic idea of this method is to obtain the macroscopic constitutive relationships from the resolution of the microscopic boundary value problem (BVP) defined on a representative volume element. This method does not requires any constitutive assumption at the macroscopic level, but an appropriate microscopic boundary condition has to be defined. Our work focuses on the unified treatment of the microscopic boundary condition in a multiphysics microscopic BVP. In particular, an efficient way to compute the tangent operator is developed for an arbitrary kind of boundary conditions. When considering the FE2method, the homogenized stresses and homogenized tangents at every macroscopic integration points are required. From the energy consistency condition between macroscopic and microscopic problems, the homogenized stresses can be easily computed by the volumetric averaging integrals of the microscopic counterparts. The required homogenized tangents often follows a stiffness condensation from the microscopic stiffness matrix at the equilibrium state [2]. When using the stiffness condensation, the microscopic stiffness matrix needs to be partitioned, and dense matrices based on Schur complements (under a matrix form 𝐊̃ 𝑏𝑏=𝐊𝑏𝑏−𝐊𝑏𝑖𝐊𝑖𝑖−1𝐊𝑖𝑏) have to be estimated. The matrix operations based on Schur complements require a large time consuming and a lot of memory when increasing the number of degrees of freedom of the microscopic BVPs. This work proposes an efficient method allowing to compute the homogenized tangents without significant effort. The microscopic stiffness matrix does not need to be partitioned. The homogenized tangents are computed by solving a linear system, which is based on the linearized system at the converge solution of the microscopic BVP, with multiple right hand sides. With proposed numerical improvements, the FE2 method is used in a fully thermo-mechanically-coupled simulation. The temperature-dependent elastoplastic behavior, thermal conduction as well as the heat conversion from the mechanical deformation are considered in the hyperelastic large strain framework. [1]. Geers, M. G. D., Kouznetsova, V. G., Brekelmans, W. A. M., 2010. J. Comput. Appl. Math. 234 (7), 2175-2182. [2]. Kouznetsova, V., Brekelmans, W. A. M., Baaijens, F. P. T., 2001. Comput. Mech. 27 (1), 37-48. [less ▲]

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See detailSécurité et santé au travail dans les bassins miniers wallons des années ’50
Geerkens, Eric ULg

Conference (2016, September 08)

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See detailMeasurement of Innovation: Where Do We Stand?
Artige, Lionel ULg

Conference (2016, September 08)

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See detailA coupled electro-thermo-mechanical discontinuous Galerkin method applied on composite materials
Homsi, Lina ULg; Noels, Ludovic ULg

Conference (2016, September 07)

Carbon fiber reinforced polymer composites have become increasingly important due to their unique properties which are appreciated in many practical applications such as low weight, low cost, low density ... [more ▼]

Carbon fiber reinforced polymer composites have become increasingly important due to their unique properties which are appreciated in many practical applications such as low weight, low cost, low density, high mechanical characteristics. Moreover the range of their electrical conductivity can be controlled by the amount of carbon fibers. Carbon fiber reinforced polymer composites consist of at least two components, a polymer matrix (generally dielectric) and electrically conductive fillers. This combination results in multifunctional composites, both structural and conductive. The existence of the polymer matrix will avoid catastrophic failure due to fiber breaking, and the existence of the carbon fibers will enhance strength and stiffness on one hand, and will allow to a significant temperature gradient when electric current is applied on the other hand. The objective of this paper is to study the response of the carbon fiber reinforced polymer composites when an electric power is applied and to determine the effective properties. To this end governing equations describing electro-thermo-mechanical coupling in composite materials are developed and discretized using the Discontinuous Galerkin (DG) finite element method. DG methods have many advantages such as optimal convergence and local approximation properties in addition to their flexibility for mesh adaption and their straightforward use of high order polynomial approximations. A micromechanical model of unidirectional carbon fibers dispersed in a polymer matrix is formulated considering the interaction of electrical, thermal and mechanical fields It is then solved using the DG method to determine the time dependent response of the electro-thermo-mechanical coupling and quantify the variation of the fields. [less ▲]

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See detailGPS, Galileo and BeiDou inter-system biases estimation in relative positioning with code and phase pseudoranges
Deprez, Cécile ULg; Warnant, René ULg

Conference (2016, September 07)

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the Chinese BeiDou satellite system and the ... [more ▼]

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the Chinese BeiDou satellite system and the European Galileo program have experienced major progress in 2015 and 2016 with the launch of 7 and 8 satellites respectively. Associated with the ongoing GPS modernization, many more frequencies and satellites are now available. Therefore, multi-GNSS relative positioning based on overlapping frequencies should entail better accuracy and reliability in position estimations. However, the differences between satellite systems induce inter-system biases (ISBs) inside the multi-GNSS equations of observation. The combined use of L1 and L5 from GPS with E1 and E5a from Galileo, B2 from BeiDou and E5b from Galileo in zero baseline double differences (ZB DD) based on a unique pivot satellite is employed to resolve ISBs. This model removes all the satellite- and receiver-dependent error sources by differentiating and the zero baseline configuration allows atmospheric and multipath effects elimination. An analysis of the long-term stability of ISBs (GPS- Galileo and Galileo - BeiDou) is conducted onvariouspairsof receiversover large timespans. Thepossibleinfluenceof temperature variations inside the receivers over ISB values is also investigated. Our study is based on the 6 multi-GNSS receivers (2 Septentrio PolaRx4, 1 Septentrio PolaRxS, 1 Septentrio PolaRx5 and 2 Trimble NetR9) installed on the roof of our building in Liege. The estimated ISBs are then used as corrections in the multi-GNSS observation model and the resulting accuracy of multi-GNSS positioning is compared to GPS, Galileo and BeiDou standalone solutions. [less ▲]

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See detailProbabilistic prediction of the quality factor of micro-resonator using a stochastic thermo-mechanical multi-scale approach
Wu, Ling ULg; Lucas, Vincent ULg; Golinval, Jean-Claude ULg et al

Conference (2016, September 07)

As the size of the device is only one or two orders of magnitude higher than the size of the grains, the structural properties, such as the thermo-elastic quality factor (Q), of micro-electro-mechanical ... [more ▼]

As the size of the device is only one or two orders of magnitude higher than the size of the grains, the structural properties, such as the thermo-elastic quality factor (Q), of micro-electro-mechanical systems (MEMS) made of poly-crystalline materials exhibit a scatter, due to the existing randomness in the grain size, grain orientation, surface roughness... In order to predict the probabilistic behavior of micro-resonators, the authors extend herein a previously developed stochastic 3-scale approach [1] to the case of thermoelastic damping [2]. In this method, stochastic volume elements (SVEs) [3] are defined by considering random grain orientations in a tessellation. For each SVE realization, the mesoscopic apparent elasticity tensor, thermal conductivity tensor, and thermal dilatation tensor can be obtained using thermo-mechanical computational homogenization theory [4]. The extracted mesoscopic apparent properties tensors can then be used to define a spatially correlated meso-scale random field, which is in turn used as input for stochastic finite element simulations. As a result, the probabilistic distribution of the quality factor of micro-resonator can be extracted by considering Monte-Carlo simulations of coarse-meshed micro-resonators, accounting implicitly for the random micro-structure of the poly-silicon material. [1] V. Lucas, J.-C. Golinval, S. Paquay, V.-D. Nguyen, L. Noels, L. Wu, A stochastic computational multiscale approach; Application to MEMS resonators. Computer Methods in Applied Mechanics and Engineering, 294, 141-167, 2015. [2] L. Wu, V. Lucas, V.-D. Nguyen, J.-C. Golinval, S. Paquay, L. Noels, A Stochastic Multiscale Approach for the Modeling of Thermoelastic Damping in Micro-Resonators. Submitted. [3] M. Ostoja-Starzewski, X.Wang, Stochastic finite elements as a bridge between random material microstructure and global response, Computer Methods in Applied Mechanics and Engineering, 168, 35--49, 1999. [4] I. Özdemir, W. A. M. Brekelmans, M. G. D. Geers, Computational homogenization for heat conduction in heterogeneous solids, International Journal for Numerical Methods in Engineering 73, 185-204, 2008. [less ▲]

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See detailGeneralized Pascal triangle for binomial coefficients of words : an overview
Stipulanti, Manon ULg

Conference (2016, September 07)

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word ... [more ▼]

We introduce a generalization of Pascal triangle based on binomial coefficients of finite words. These coefficients count the number of times a finite word appears as a subsequence of another finite word. Similarly to the Sierpiński gasket that can be built as the limit set, for the Hausdorff distance, of a convergent sequence of normalized compact blocks extracted from Pascal triangle modulo 2, we describe and study the first properties of the subset of [0, 1] × [0, 1] associated with this extended Pascal triangle modulo a prime p. Then we create a new sequence from this extended Pascal triangle that counts, on each row of this triangle, the number of positive binomial coefficients. We study some properties of this sequences. To be precise, we investigate some properties regarding the regularity of the sequence. To extend our work, we construct a Pascal triangle using the Fibonacci representations of all the nonnegative integers and we define the corresponding sequence of which we study the regularity. This regularity is an extension of the classical k-regularity of sequences. [less ▲]

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See detailInterfaces in multi-material architectures fabricated by polyjet printing
Zorzetto, Laura ULg; Rink, Marta; Briatico Vangosa, Francesco et al

Conference (2016, September 07)

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See detailSimulations of composite laminates inter and intra-laminar failure using on a non-local mean-field damage-enhanced multi-scale method
Wu, Ling ULg; Adam, Laurent; Bidaine, Benoît et al

Conference (2016, September 07)

The failure of carbon fiber reinforced composite laminates is studied using a multiscale method. A non-local mean-field homogenization (MFH) method accounting for the damage evolution of the matrix phase ... [more ▼]

The failure of carbon fiber reinforced composite laminates is studied using a multiscale method. A non-local mean-field homogenization (MFH) method accounting for the damage evolution of the matrix phase of the composite material [1] is considered in each ply in order to capture the intra-laminar failure. In that formulation, an incremental-secant MFH approach is used to account for the elastic unloading of the fibers during the strain softening of the matrix. In order to avoid the strain/damage localization caused by the matrix material softening, the damage enhanced MFH was formulated in an implicit non-local way [2]. Accurate predictions of the composite softening behavior and of the different phases response is then achieved. The delamination process is modeled by recourse to a hybrid discontinuous Galerkin (DG)/ extrinsic cohesive law approach. An open-hole composite laminate with a quasi-isotropic sequence ([90/45/-45/90/0]S) is then studied experimentally and using the multiscale method [3]. The numerical model is found to predict the damage bands along the fiber directions in agreement with the experimental samples inspected by X-ray computed tomography (XCT). Moreover, the predicted delamination pattern is found to match the experimental observations. Finally, with a view to stochastic analysis, the effect of the volume fraction and orientation variations on the failure is studied by defining them as random variables. REFERENCES [1] L. Wu, L. Noels, L. Adam, I. Doghri, An implicit-gradient-enhanced incremental-secant mean- field homogenization scheme for elasto-plastic composites with damage, International Journal of Solids and Structures, 50, 3843-3860, 2013. [2] R. Peerlings, R. de Borst, W. Brekelmans, S. Ayyapureddi, Gradient-enhanced damage for quasi-brittle materials. International Journal for Numerical Methods in Engineering, 39, 3391-3403, 1996. [3] L. Wu, F. Sket, J.M. Molina-Aldareguia, A. Makradi, L. Adam, I. Doghri, L. Noels, A study of composite laminates failure using an anisotropic gradient-enhanced damage mean-field homogenization model, Composite Structures, 126, 246–264, 2015. [less ▲]

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See detailYes we can! Implementing digitization requests in Alma
Renaville, François ULg; Brownlie, Helen; Read, Simon et al

Conference (2016, September 06)

Enabling patron digitization requests is one of those (new) exciting services that end users appreciate! Alma allows patrons and staff members to request the creation of a digital file for any physical or ... [more ▼]

Enabling patron digitization requests is one of those (new) exciting services that end users appreciate! Alma allows patrons and staff members to request the creation of a digital file for any physical or electronic item. Alma digitization request workflow is configurable according to the library’s requirements, created via Alma or Primo, partial or full, limited to some user groups, limited in numbers, with or without approval process, digitized materials added to collections and made accessible to registered and/or guest users via Primo, etc. So Alma libraries can deal with a lot of different options to satisfy their patrons' needs. This session will present the development and launch of digital fulfillment from the perspective of 3 institutions (the University of Otago Library, the University of Liege Library, and the University of Sheffield Library) focusing on the strategic choices that were made, the implementation, and the final delivery of the services to their communities. [less ▲]

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See detailUltra-narrow superconducting junctions: electromigration to shed light on quantum point contacts
Baumans, Xavier ULg; Cerbu, Dorin; Adami, Obaïd-Allah ULg et al

Conference (2016, September 06)

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and in quantum computing circuits. In this context, it is of ... [more ▼]

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and in quantum computing circuits. In this context, it is of fundamental importance to better understand the undesired and harmful appearance of thermal and quantum fluctuations of the superconducting order parameter [1]-[3] as a function of the wire width. Although superconductors in the mesoscopic regime (i.e. size comparable to ξ and/or λ) have been explored both experimentally and theoretically in depth, the superconducting nanoworld (i.e. at scales of the fermi wavelength) has received much less attention. The lack of experimental results is in part due to the difficulty of sample fabrication, at dimensions beyond the limit reached by conventional lithographic techniques. A promising direction consists of controlling the local displacement of atom by an electron wind, a process known as electromigration (EM) [4] . This effect relies on the combination of local temperature rise and substantial current crowding at nanoconstrictions. While uncontrolled, EM is responsible for the breakdown of small electronic devices, it can be used in a controllable way to further decrease locally the cross section of the nanowire towards single atomic contacts. In this work, we explore in-situ controlled EM to fabricate nano-constrictions immersed in cryogenic environment. We demonstrate that a transition from thermally assisted phase slips (TAPS) to quantum phase slips (QPS) takes place when the effective cross section becomes smaller than ~ 150 nm 2 . In the regime dominated by QPS the nanowire loses completely its capacity to carry current without dissipation, even at the lowest possible temperature [5] . We also demonstrate that the bow-tie shaped constrictions exhibit a negative magnetoresistance at low magnetic fields [5] which can be attributed to the suppression of superconductivity in the contact leads [6] . Strikingly, the detrimental effect caused by the repeated EM can be healed by simply inverting the current direction. These findings reveal the strong potential of the proposed fabrication method to explore various fascinating superconducting phenomena in atomic-size constrictions. [less ▲]

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See detailSubsidence in the Sept Iles layered intrusion (Canada) revealed by anisotropy of magnetic susceptibility
Bolle, Olivier ULg; Diot, Hervé; Fransen, William ULg et al

Conference (2016, September 06)

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See detailAre Christmas tree plantations a suitable habitat for farmland birds?
Gailly, Robin ULg; Paquet, Jean-Yves; Titeux, Nicolas et al

Conference (2016, September 06)

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may ... [more ▼]

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may likely impact farmland birds. Impacts on birds have been examined for bioenergy agricultural systems, such as miscanthus plantations and short rotation willow coppice. In Europe, the extend of Christmas tree plantations (CTP) has recently increased dramatically in farmland but their impacts on farmland birds remains largely unknown. We examined the extent to which CTP in southern Belgium alter bird species assemblages compared to traditional farmland. The presence and abundance of birds were recorded twice during a breeding season in randomly selected sites located in farmland areas with and without CTP. Results show that the conversion of traditional farmland into CTP modifies bird species assemblages and locally increases bird diversity and density without inducing biotic homogenization. This observed pattern indicates that CTP might constitute an interesting alternative habitat for farmland birds. However bird presence or abundance may be confounding indicator of habitat quality because individuals may be attracted to low-quality habitats in human modified landscapes. The European Stonechat Saxicola rubicola was chosen as a model species to investigate the quality of CTP as a breeding habitat in more details. Habitat quality in CTP was assessed with measures of reproductive success and survival. These measures were compared with those collected in traditional farmland. Although vegetation structure, field management and nest placement are highly different between habitat types, our first results suggest that CTP are not of lesser quality than traditional farmland for the European Stonechat. [less ▲]

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See detailInternet Platforms for Education on Sustainability
Pfennig, Andreas ULg

Conference (2016, September 05)

One challenge in teaching sustainability results from the expertise being distributed in various universities. At the same time society would not require so many experts focused on sustainability that ... [more ▼]

One challenge in teaching sustainability results from the expertise being distributed in various universities. At the same time society would not require so many experts focused on sustainability that corresponding purely sustainability-oriented curricula should be offered in a majority of universities. Thus sustainability aspects have to be integrated into existing curricula e.g. in chemical engineering studies. To offer sufficiently high-level courses or teaching content, one way is to share modules dealing with sustainability aspects. The idea to share teaching capabilities on a national or international level is not new, some examples are sustainicum.at, bioenergytrain.eu. While these approaches address the topic of sustainability with a relatively wide variety of facets, it is difficult to see, how a coherent picture can be obtained and transferred in education to students and the interested public. While this is so, already regarding the most basic element of the versatile toolbox of chemical engineering, namely setting up and solving simple balances, leads to significant insights and especially a fundamental understanding on the basic interplay of at least some of the major drivers. These are – besides increasing world population, which is the main driver – the increasing energy consumption, the limited land area for food and bioenergy production, the finite size even of the atmosphere leading to an increase in CO2 concentration and climate change, to name just a few. All of these aspects refer to limited resources for which balances can be set up and solved. The balances have the advantage that they are so simple that everybody can assess their validity and implications. The experience with working out a corresponding teaching module will be presented exemplarily. To facilitate delivering the aspects to students and the interested public the teaching material including a full manuscript and power-point slides have been worked out and are supplied at sustainicum.at. To allow easy access to the content of this teaching material also corresponding lectures have been recorded and are made publicly available through YouTube. The technical boundary conditions, which were found to be quite optimal as compared to other public lectures available on the internet, will be presented. The teaching material has in the past also been used for a variety of own presentations with the aim to deliver the basic understanding to an interested public, including public conference series or school classes. From these various experiences conclusions are drawn which will be presented. Introduction: One challenge in teaching sustainability results from the expertise being distributed in various universities. At the same time society would not require so many experts focused on sustainability that corresponding purely sustainability-oriented curricula should be offered in a majority of universities. Thus sustainability aspects have to be integrated into existing curricula e.g. in chemical engineering studies. To offer sufficiently high-level courses or teaching content, one way is to share modules dealing with sustainability aspects. The idea to share teaching capabilities on a national or international level is not new, some examples are sustainicum.at, bioenergytrain.eu. While these approaches address the topic of sustainability with a relatively wide variety of facets, it is difficult to see, how a coherent picture can be obtained and transferred in education to students and the interested public. Exemplary Topic: While this is so, already regarding the most basic element of the versatile toolbox of chemical engineering, namely setting up and solving simple balances, leads to significant insights and especially a fundamental understanding on the basic interplay of at least some of the major drivers. These are – besides increasing world population, which is the main driver – the increasing energy consumption, the limited land area for food and bioenergy production, the finite size even of the atmosphere leading to an increase in CO2 concentration and climate change, to name just a few. All of these aspects refer to limited resources for which balances can be set up and solved. The balances have the advantage that they are so simple that everybody can assess their validity and implications. The experience with working out a corresponding teaching module will be presented exemplarily. Results and Conclusions: To facilitate delivering the aspects to students and the interested public the teaching material including a full manuscript and power-point slides have been worked out and are supplied at sustainicum.at. To allow easy access to the content of this teaching material also corresponding lectures have been recorded and are made publicly available through YouTube. The technical boundary conditions, which were found to be quite optimal as compared to other public lectures available on the internet, will be presented. The teaching material has in the past also been used for a variety of own presentations with the aim to deliver the basic understanding to an interested public, including public conference series or school classes. From these various experiences conclusions are drawn which will be presented. [less ▲]

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See detailPhase Slips In Tunable Width Point Contacts Created By Electromigration
Silhanek, Alejandro ULg

Conference (2016, September 05)

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and as interconnects in circuits proposed for quantum computing ... [more ▼]

Superconducting nanowires have been, for years now, a topic of great interest due to their potential application in single photon detectors and as interconnects in circuits proposed for quantum computing. In this context, it is of fundamental importance to better understand the undesired and harmful appearance of thermal and quantum fluctuations of the superconducting order parameter as a function of the wire width. In this presentation, we explore in-situ controlled electromigration (EM) to fabricate nano-constrictions immersed in cryogenic environment. We demonstrate that a transition from thermally assisted phase slips (TAPS) to quantum phase slips (QPS) takes place when the effective cross section becomes smaller than ~150 nm^2. In the regime dominated by QPS the nanowire loses completely its capacity to carry current without dissipation, even at the lowest possible temperature. We also demonstrate that the bow-tie shaped constrictions exhibit a negative magnetoresistance at low magnetic fields which can be attributed to the suppression of superconductivity in the contact leads. Strikingly, the detrimental effect caused by the repeated EM can be healed by simply inverting the current direction. These findings reveal perspectives of the proposed fabrication method for exploring various fascinating superconducting phenomena in atomic size constrictions. [less ▲]

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See detailBalanced words and related concepts: applications and complexity issues
Crama, Yves ULg

Conference (2016, September 05)

In this talk, I present a few results and several questions about "regular" sequences of integers and related concepts, such as balanced words, partitions and covers of the integers by arithmetic ... [more ▼]

In this talk, I present a few results and several questions about "regular" sequences of integers and related concepts, such as balanced words, partitions and covers of the integers by arithmetic sequences. Such concepts have been investigated in pure mathematics, but also naturally arise in a variety of application fields such as production planning, political science, or queueing theory. I briefly present some of these applications and explain how they motivate seemingly new questions relating, for instance, to the algorithmic complexity of regular partitions, or to the structure of balanced words. The presentation is based on joint work with Nadia Brauner and Vincent Jost (Grenoble). [less ▲]

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See detailInstability and abrupt changes in marine ice sheet behaviour
Bulthuis, Kevin ULg; Arnst, Maarten ULg; Pattyn, Frank et al

Conference (2016, September 05)

The West Antarctic ice sheet (WAIS), whose bedrock is to a large extent below sea level, has been identified as a tipping element in Earth’s climate system because it could dramatically re- treat and ... [more ▼]

The West Antarctic ice sheet (WAIS), whose bedrock is to a large extent below sea level, has been identified as a tipping element in Earth’s climate system because it could dramatically re- treat and cause important sea-level rise. Different mechanisms underlying instabilities of such marine ice sheets have been proposed in the literature, but the risk that these mechanisms could trigger an accelerated retreat of the WAIS is still an open question. In this oral communication, which results from the literature study that I carried out during this ongoing first year of my PhD, I will review two main mechanisms that can cause marine ice sheet instability. The first mechanism is the marine ice sheet instability explained by Weertman who hypothe- sizes that marine ice sheets grounded on bedrocks which deepen inland can be inherently unstable. I will focus my attention on the stability of the steady states of this nonlinear dyna- mical system, as well as on the critical values of the external forcing parameters responsible for abrupt changes in the system behaviour (critical transitions). I will review how geological data suggest that rapid ice sheet retreats explained by Weertman’s hypothesis occurred in Antarctica during the Pleistocene and the early Holocene. The recently observed accelerated ice loss of the Pine Island and Thwaites glaciers of the WAIS could also be considered as a consequence of this instability mechanism and could lead to an important contribution to sea-level rise in the future. The second mechanism that I will review is the binge-purge oscillation mechanism which could have caused the disintegration of the Laurentide ice sheet during the last glacial period. These oscillations could also explain future behaviour of the WAIS. Binge-purge oscillations are short periods of enhanced ice flow (purge phase) followed by periods of much slower flow (binge phase). These oscillations are usually explained by a thermal-gravitational instability which takes place when basal conditions change. I will focus my attention on the mathematical and physical conditions which can trigger this instability process, as well as on examples of such oscillations in the WAIS in the past. [less ▲]

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See detailNon-destructive measurements of the volume magnetic behavior of large bulk GdBCO single domains and ferromagnet/superconductor structures
Vanderbemden, Philippe ULg; Egan, Raphael; Morita, Mitsuru et al

Conference (2016, September 05)

The present work deals with magnetic measurements on bulk large grain GdBa2Cu3O7 (GdBCO) single domains using a recently constructed bespoke magnetometer [Rev. Sci. Instrum. 86 025107 (2015)]. The device ... [more ▼]

The present work deals with magnetic measurements on bulk large grain GdBa2Cu3O7 (GdBCO) single domains using a recently constructed bespoke magnetometer [Rev. Sci. Instrum. 86 025107 (2015)]. The device enables the measurement of magnetic moments as large as 1 Am^2 (1000 emu) on large bulk samples up to 20 mm diameter at 77 K. This extends significantly the accessible measurement range of “off-the shelf” magnetometers (e.g. SQUID, VSM). Unlike Hall probe mapping, the measured signal is representative of the superconducting currents flowing across the entire height of the sample. Since the device is based on a flux extraction technique and does not include any Hall probe, another advantage is that no gap between a Hall probe and the sample needs to be taken into account to interpret the results. In the present work we first show how the dimensions of the sensing coils and integration bounds are chosen in such a way the magnetometer is sensitive to dipolar magnetic moment of the sample, while being insensitive to moments of higher order. Next we study the relaxation of the trapped magnetic moment under various magnetization processes. The sensitivity of the device allows small variations of m (e.g. ~ 2% for 1 hour) to be recorded. We show experimentally that the relaxation of the magnetic moment of the whole sample is reduced strongly if the superconductor is not fully magnetized, either in field cooled (FC) or zero-field cooled (ZFC) conditions. The practical consequence is that an abnormally slow magnetic relaxation (large E-J power law exponent n) under a conventional magnetization procedure indicates that the bulk superconductor could be magnetized further. In a second set of experiments, we study the increase of magnetic moment of a bulk superconductor when it is attached to a soft ferromagnetic disk. We also examine the irreversible demagnetization of these structures when subjected to crossed magnetic fields and compare to the magnetic moment of a classical (Nd-Fe-B) permanent magnets in the same conditions. Acknowledgements: This work is part of an "Action de Recherches Concertees" grant (ARC 11/16 -03) from the "Communaute Francaise de Belgique". [less ▲]

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See detailImprinting superconducting vortex trajectories in a magnetic layer
Shaw, Gorky ULg

Conference (2016, September 05)

We experimentally show that the principle of local polarization of a magnetic layer can be applied for imprinting, into a soft magnetic layer of permalloy (Py), the trajectory of vortices moving in a ... [more ▼]

We experimentally show that the principle of local polarization of a magnetic layer can be applied for imprinting, into a soft magnetic layer of permalloy (Py), the trajectory of vortices moving in a superconducting film (Nb). In full analogy with a magnetic drawing board, vortices act as tiny magnetic scribers leaving a wake of polarized magnetic media in the Py layer. We have used the magneto-optical imaging technique to investigate the mutual interaction between superconducting vortices and ferromagnetic domains. In general, we observe that the flux propagation is delayed at the border of the magnetic layer. For thick Py layers, the stripe magnetic domain pattern guides the smooth flux penetration as well as the abrupt vortex avalanches in the Nb film. More interestingly, in thin Py layers without stripe domains, vortices leave clear imprints of locally polarized magnetic moments along their trajectories. Furthermore, the printings were found to be stable and could still be observed at room temperature, allowing for ex situ observation of the flux penetration in superconductors. We expect our findings to pave the way for further studies for optimizing magnetic recording of superconducting vortex trajectories. [less ▲]

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See detailTowards a data model for (inter)textual relationships. Connecting Ancient Egyptian texts and understanding scribal practices
Polis, Stéphane ULg; Razanajao, Vincent ULg; Sojic, Nathalie ULg

Conference (2016, September 05)

The goal of this lecture is theory-oriented: we propose a conceptual data model that allows us to deal with complex textual relationships. It is empirically grounded in our experience of digital ... [more ▼]

The goal of this lecture is theory-oriented: we propose a conceptual data model that allows us to deal with complex textual relationships. It is empirically grounded in our experience of digital annotation of Ancient Egyptian texts. This paper is initially born out of the practical need of annotating and linking together hundreds of textual witnesses in the framework of the Ramses project (Polis et al. 2013; Polis & Winand 2013), the aim of which is to build and publish online (http://ramses.ulg.ac.be) the first richly annotated corpus of Late Egyptian texts (c. 1350-900 BCE). [less ▲]

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See detailNew crystallographic data on several uranyl minerals
Dal Bo, Fabrice ULg; Hatert, Frédéric ULg; Philippo, Simon

Conference (2016, September 04)

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See detailCo-producing evidence: Ethnographic inquiry of a "wild" search for causation
Duysens, Fanny ULg

Conference (2016, September 03)

Drawing on a multi-sited ethnography which explores the field of patients’ organizations (POs) concerned with genetic disorders within the Belgian context, this communication is interested in some ... [more ▼]

Drawing on a multi-sited ethnography which explores the field of patients’ organizations (POs) concerned with genetic disorders within the Belgian context, this communication is interested in some knowledge-related collaboration between POs and scientific and medical experts, or “wild research” projects (Callon & Rabeharisoa, 2003). Especially, it examines an informant's narrative of the "wild" search for causation of the disorder by which his family is concerned and the inherent forms and modalities of knowledge production, circulation and validation. While STS scholars have traditionally seen POs as epistemic communities, they currently point out an increasing engagement in such novel forms of collaboration over the last decades. This leads to the emergence of a certain “evidence-based activism” (EBA) among POs, characterized by a growing articulation of credential and more “experiential” knowledge to define common epistemologies of the conditions they are concerned with. The springs of this articulation remain to be explored. Thus, the aim is to flesh out the recent concept of EBA, to empirically question what it covers, and how new biomedical knowledge is generated by “evidence activists”. Rather than provoking “radical openings in technoscientific practice”, our observations show a continuous co-production of knowledge taking place within POs engaged in EBA. So, this paper will take stock of these transformations and envisage the affordances and blind spots for STS of the use of new concepts such as EBA. [less ▲]

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See detailAssessing Basic Motor Competencies in Primary School – an International Comparative Study in Europe
Scheuer, Claude; Cloes, Marc ULg; Colella, Dario et al

Conference (2016, September 03)

A central aim of primary physical education (PE) is the promotion of physical competencies as a necessary condition of developing a physically active lifestyle and to be able to participate in the Olympic ... [more ▼]

A central aim of primary physical education (PE) is the promotion of physical competencies as a necessary condition of developing a physically active lifestyle and to be able to participate in the Olympic community. We defined basic motor competencies as physical performance dispositions, which evolved from task-specific requirements in the culture of sports and exercise. They are supposed to be learnable, based on previous experiences and can be improved through practice. Potential evaluations of effects in PE need to consider situation-specific and context-dependent characteristics of PE as well as prior experiences of pupils. Therefore, a design for test items, which are closely related to PE and vary in difficulty depending on the age of the pupils, is necessary. For this purpose, we developed the MOBAK-1 test instrument for the assessment of basic motor competencies in first graders. It allows teachers to identify groups in need of special support, and initiate these support measures to reduce inequalities. The first study took place in Zurich (Switzerland) and focused on construct validity (e.g., the factorial validity of the instrument). Between spring 2015 and spring 2016, the MOBAK-1 test instrument was and will be implemented in further countries in Europe. At this time, we have four samples of four different countries: (1) Switzerland (Zurich) (N = 317; girls = 55%; age: M = 7.04 years [SD = .37]; BMI = 16.08 [SD = 2.25]) assessed by University of Basel (Dr. Christian Herrmann); (2) Germany (Frankfurt) (N = 1061; girls = 45%; age: M = 6.80 years [SD = .89]; BMI = 16.30 [SD = 2.37]) assed by University of Frankfurt (Prof. Dr. Christopher Heim); (3) Lithuania (Kaunas) (N = 120; girls = 48%; age: M = 7.76 years [SD = .33]; BMI = 16.14 [SD = 2.30]) assessed by Lithuanian Sports University (Assoc. Prof. Dr. Arunas Emeljanovas); (4) Italy (Foggia) (N = 85; girls = 45%; age: M = 7.24 years [SD = .30]; BMI = 17.53 [SD = 3.04]) assessed by University of Foggia (Prof. Dr. Dario Colella). Further samples are currently on the way to be completed in four other countries: (1) Luxembourg (N = 280) assessed by University of Luxembourg (Claude Scheuer); (2) Slovakia (Trnava) (N = 240) assessed by University of Trnava (Dr. Dana Masarykova); (3) Czech Republic (Brno) (N = 600) assessed by University of Brno (Dr. Petr Vlcek); (4) Belgium (Liège) (N = 450) assessed by University of Liège (Prof. Dr. Marc Cloes and Dr. Boris Jidovtseff). In the initial validation study in Switzerland, two factors consisting of four items each were found. The related EFA (Study 1: CFI=.98; RMSEA=.024) and CFA (Study 2: CFI =.95; RMSEA=.044) revealed good model fit indices. The first factor “Locomotion” represents body movements (e.g., balancing), the second factor “Object-control” represents ball control (e.g., catching). Conclusions: The developed MOBAK test instrument meets psychometric validity demands based on the Swiss data. The presentation will show the results of the validation studies in further European countries and the results of the comparative study. [less ▲]

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See detailUrban soils with a sideway glance
Meulemans, Germain ULg

Conference (2016, September 03)

The soils of cities are becoming an important subject for the soil sciences, triggering revisions in their usual modes of research and concepts. One implication of this is the resort to the 'ecological ... [more ▼]

The soils of cities are becoming an important subject for the soil sciences, triggering revisions in their usual modes of research and concepts. One implication of this is the resort to the 'ecological engineering' of soils, framed as a research in soil processes through the active making of soils from scratch. In this, several voices from inside the Soil sciences call for a move from descriptive research to open-ended experimentation. A similar move has also been called for in anthropology. Ingold, notably, suggests to revive the 'craft of anthropology' (2008), encouraging anthropologists to participate in the carrying on of life through craft and experimentation, rather than restraining to retrospective accounts of its unfolding dynamics. How, then, can turns towards making resonate between the practices of soil scientists and those of the anthropologists that attempt to study them? In this paper, I present a collaborative experiment between artists, anthropologists and soil scientists that was carried out in a series of residences near Paris between 2015 and 2016. The residential sessions consisted in a continuation and speculative exploration of the questions raised in both the soil sciences and anthropology in an experimental, creative way - addressing the intertwinement of human and soil becomings from direct engagement with them. The paper addresses how such experiments can be a research process, aimed at exploring the world 'with a sideway glance' (Ingold, 2008). The paper concludes with open questions on where anthropological investigation through art making might play a role in the future of disciplinarities. [less ▲]

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See detail“That’s only statistics”:Recording PPPs in national accounts
Piron, Damien ULg

Conference (2016, September 02)

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See detailLe potentiel des blogues et des réseaux numériques dans l'apprentissage d'une langue étrangère
Vintila, Elena-Georgiana ULg

Conference (2016, September 02)

We selected two French foreign language textbooks published in Romania under the Ministry of Education in 2004 and 2005 by the same publishing house and we will analyze the modality of presentation of ... [more ▼]

We selected two French foreign language textbooks published in Romania under the Ministry of Education in 2004 and 2005 by the same publishing house and we will analyze the modality of presentation of grammar points offered by textbooks and selected blogs. For this analysis, we will focus on: the appearance of textbooks, respectively blogs, the presentation of the grammar point set analysis, types and number of exercises. In addition, we will try to see what socio-cultural values ​​are highlighted by the authors and how bloggers alter through publications. [less ▲]

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See detailThe influence of COMT on the neural substrates of short-term memory in normal aging
Manard, Marine ULg; Salmon, Eric ULg; Collette, Fabienne ULg

Conference (2016, September 02)

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not ... [more ▼]

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not allow to easily disentangle the contribution of maintenance and manipulation processes. We explored the effect of COMT genotype on the maintenance process using a Sternberg memory task varying the amount of information presented, in young and older homozygous carriers for the Val and Met alleles of the COMT gene. Although no clear behavioral difference was observed between groups, patterns of cerebral activity indicate difficulties for Met older individuals to maintain stable representations. These results will be discussed in terms of dopaminergic contribution to stability/flexibility of cognitive processes during aging. [less ▲]

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See detailImpact of high-wheat bran diet on sows’ microbiota, performances and progeny’s growth and health
Leblois, Julie ULg; Bindelle, Jérôme ULg; Dehareng, Frédéric et al

Conference (2016, September 02)

Finding alternatives to antimicrobial growth promoters is part of the goal of improving sustainability in pig production. Dietary fibres are considered as health-promoting substances acting on pigs’ ... [more ▼]

Finding alternatives to antimicrobial growth promoters is part of the goal of improving sustainability in pig production. Dietary fibres are considered as health-promoting substances acting on pigs’ microbiota. This study aimed to investigate whether the enrichment of sows’ diet with high levels of wheat bran (WB) could impact the performances of sows and piglets’ health. Seven sows were fed a control diet (CON) and 8 sows a WB diet from day 43 of gestation (WB 240 g/kg DM) until the end of the lactation period (WB 140 g/kg DM). Diets were formulated to be iso-energetic and iso-nitrogenous by changing the proportions of some ingredients. Faeces were sampled at different time points (before treatment, during treatment: in gestation and lactation) to determine microbiota composition (sequencing with Illumina MiSeq). Milk was sampled weekly to determine lactose, fat and protein concentration by mid-infrared technology and IgA and IgG contents by ELISA. Before weaning (d26-27), piglets were euthanized, intestinal contents and tissues sampled for further analyses. Zootechnical performances of sows and piglets were recorded. Statistical analyses were performed using the SAS MIXED procedure and repeated measurements. Treatment never impacted piglets’ weight (P=0.51). Sows’ ingestion during the lactation period was comparable between both treatments until the last 4 days of lactation where the percentage of target ingestion was significantly (P<0.001) lower for the WB (66%) compared to the CON group (89%). No effect on sows’ backfat and weight changes was observed. An increased abundance of Lactobacillus spp. in feces of the WB group was observed in gestation before and after diet change (8.8% vs 15.1% of total bacteria). However, for the overall genera changes between treatments, it only seems to occur for minor groups of bacteria. Milk protein, fat, IgG and IgA were not affected by treatment, but a time-effect (P<0.001) was observed while treatment impacted (P<0.05) lactose content. In conclusion, sows’ performances were not affected by the high WB diet and more research on the piglets’ samples is foreseen. [less ▲]

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See detailIntegrating Science and Technology into Sports: A Case Study of Sports Innovations in Belgium
Van Oudheusden, Michiel ULg; Van Hoyweghen, Ine

Conference (2016, September 01)

This paper explores the dynamic interplay between sports and innovation policies, research and development processes, and science-driven sports practices in Wallonia and Flanders (Belgium). Here, as in ... [more ▼]

This paper explores the dynamic interplay between sports and innovation policies, research and development processes, and science-driven sports practices in Wallonia and Flanders (Belgium). Here, as in other countries and regions, the aim of integrating science and technology into sports is now a leading sports policy principle and innovation strategy. Building on science and technology studies (STS) tools and methods (vision assessment, multi-site ethnography, foresight), the paper draws out the ethical, legal, and social issues (ELSI) induced by the use of new sciences and technologies in sports. These ELSI include the client-centered nature of sports science, which raises concerns about occupational control and athlete welfare, the uptake of genetic data in sports talent detection programs, and the challenges of coordinating "data-driven" and "intuitive" sports training approaches. It is argued that as sports are scientized and technologized, such ELSI demand to be addressed by sports innovators, governing bodies, and publics. By drawing critical attention to how sports are increasingly shaped by devices, data flows, and scientists, the paper states the case for bringing sports into STS and STS into sports. [less ▲]

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See detailSuccessional trajectories of cyanobacterial communities following glacier retreat in Svalbard (High Arctic)
Stelmach Pessi, Igor ULg; Pushkareva, Ekaterina; Borderie, Fabien ULg et al

Conference (2016, September 01)

The effects of global warming are pronounced at high northern latitudes, where the warming trend observed for the past decades is almost twice as the global average. Most glaciers in Svalbard (High Arctic ... [more ▼]

The effects of global warming are pronounced at high northern latitudes, where the warming trend observed for the past decades is almost twice as the global average. Most glaciers in Svalbard (High Arctic) have been retreating and thinning since the end of the Little Ice Age in the late 19th century, and retreat rates have increased substantially in the last decades. As a glacier retreats, it systematically exposes new terrestrial habitats for the colonization by pioneering (micro)organisms. Distance from the glacier terminus can be used as a proxy for time since deglaciation, which makes glacier forefields well suited for the study of primary succession. In the present study, we investigated the successional trajectories of cyanobacterial communities along a 100-year deglaciation gradient in the forefield of two Svalbard glaciers (Ebba- and Hørbyebreen). Cyanobacterial abundance was assessed by epifluorescence microscopy and cyanobacterial diversity was investigated by pyrosequencing of partial 16S rRNA gene sequences. Filamentous cyanobacteria were more abundant than unicellular and heterocystous cyanobacteria in both forefields, and an increase in the abundance of cyanobacteria was observed along the deglaciation gradients. Pseudanabaenales was the most OTU-rich order, followed by Chroococcales, Oscillatoriales, Synechococcales, Nostocales and Gloeobacterales. At the genus level, classified phylotypes were assigned to Leptolyngbya, Phormidium, Nostoc, Pseudanabaena, Chroococcidiopsis and Microcoleus. Interestingly, OTU richness increased along the deglaciation gradient in Ebbabreen, but an inverse correlation was observed in Hørbyebreen. Beta diversity estimations indicated contrasting cyanobacterial phylogenetic structures along the temporal gradient, with a clear separation of initial (10-20 years), intermediate (30-50) and advanced (80-100) communities. Time since deglaciation accounted for around 25% of the phylogenetic variability in both forefields, with organic carbon content also explaining a significant proportion of community turnover along the deglaciation gradients. Taxonomic composition was somewhat constant along the deglaciation gradient, but OTUs associated with initial communities were related to sequences predominantely restricted to polar biotopes, while advanced communities included phylotypes related to cosmopolitan taxa. [less ▲]

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See detailHow to expand method by and for sensory: trials along and beside fieldwork
Vangeebergen, Thomas ULg

Conference (2016, September 01)

In a research with sensory analysts and flavourists, I tried other ways of interview (e.g. people auto-confrontations to their own registered activity) and other mediums to relate to the ethnographical ... [more ▼]

In a research with sensory analysts and flavourists, I tried other ways of interview (e.g. people auto-confrontations to their own registered activity) and other mediums to relate to the ethnographical work, as graphic novel or comics. [less ▲]

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See detailStrategies of the Walloon dairy breeders faced to the uncertain dairy future
Dalcq, Anne-Catherine ULg; Dogot, Thomas ULg; Soyeurt, Hélène ULg et al

Conference (2016, September 01)

This study observes the strategies, and their determinants, of the Walloon dairy breeders faced to the post quota perspective through the realization of 245 surveys, conducted from November 2014 to ... [more ▼]

This study observes the strategies, and their determinants, of the Walloon dairy breeders faced to the post quota perspective through the realization of 245 surveys, conducted from November 2014 to February 2015. Three kinds of strategical variables were defined and related to the evolution of milk production (MP) [the breeders who increase MP (HighMP) vs. keep constant MP (ConstantMP) vs. stop MP]; the valorisation of MP [alternative (ValMP) vs. classical] and the diversification of activities [with (DivMP) vs. without such activities]. The relationships between the chosen strategies and the quantitative technical variables were studied using generalized linear models. The independence between qualitative technical variables and the strategical variables was tested using Chi Square test. HighMP and ConstantMP bredeers represent 38.4% and 53.9% of respondents, respectively. HighMP breeders were significantly more declared as legal entity (p-value = 0.03), had more family members on the farm (p-value<0.01), larger agricultural area in property (p-value = 0.03) and higher MP quota (p-value = 0.01) compared to ConstantMP breeders. Only 9.8% of respondents decide to valorise differently MP. ValMP breeders tend to have more employees (p-value = 0.08) and an agricultural area less fragmented (p-value = 0.07) than classical breeders. A total of 7.8% of respondents decide to develop other activities. DivMP breeders tend to have more employees (p-value = 0.10), more agricultural area in property (p-value = 0.03) and a more recent year of installation (p-value < 0.01). Finally, 44.9% of ConstantMP breeders do not want to start an alternative valorisation of MP and diversify their activities. In conclusion, a relationship exists between, amongst others, the legal status, workforce available, characteristics of the agricultural area, the dairy production and the strategy chosen by the Walloon dairy breeders. [less ▲]

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See detailStructural design considering damage within an XFEM-level set framework
Noël, Lise ULg; Duysinx, Pierre ULg; Maute, Kurt

Conference (2016, September)

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See detailFlocculation properties of the bacterial exopolysaccharide FucoPol
Araújo, Diana; Reis, Patricia; Marques, Anna et al

Conference (2016, September)

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See detailThere is more to life than subsistence: use-wear and residue analyses on pre-Still Bay stone tools at Sibudu
Rots, Veerle ULg; Lentfer, Carol ULg; Schmid, Viola et al

Conference (2016, September)

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See detailComparing conventional excellence: moral and technical features of "good research"
Charlier, Nathan ULg

Conference (2016, September)

During a stay at Lancaster University, I was struck to discover how the institutional branding relied on the rhetoric of excellence. Several flags scattered over the campus are displaying statements such ... [more ▼]

During a stay at Lancaster University, I was struck to discover how the institutional branding relied on the rhetoric of excellence. Several flags scattered over the campus are displaying statements such as: "our physicists helped discover the Higgs boson particle", "Lancaster University is ranked among the top 10 universities in the UK", "our volcanologists made the first observation of a rare type of lava", etc. These quotes convey technologies such as rankings, but also moral and epistemological aspects regarding the role and status of scientific knowledge. This fostered my reflection regarding the fieldwork I made in different research institutions located in Belgium: while academic excellence is not at the core of their branding per se, it is indeed a key issue for many actors concerned with research governance. My paper proposes to map the different ways to frame the notion of excellence in four institutions: two large biotech research centres and two universities in Flanders and Wallonia. It relies on 25 semi-structured interviews with tenured academics involved in their institution's research management. The paper will compare how "good research" is valued in different settings: what counts when one evaluates the "excellence" of a scientific production/career? To which technologies, indicators and to which "moral principles" are interviewees referring to when they discuss excellence? How do they engage in criticizing certain framings and praise others? Eligible for the rhetoric or comparative panel, my contribution will present four distinct institutional conventions that govern research practices and sorts the good scientist from the bad. [less ▲]

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See detailBinary Phase Behavior of Saturated Triacylglycerols containing Stearic and Palmitic Acid
Bhaggan, Krishnadath ULg; Smith, K.W.; Blecker, Christophe ULg et al

Conference (2016, September)

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See detailAnalysis of the Jovian aurorae
Bonfond, Bertrand ULg

Conference (2016, September)

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See detailNonlinear vibration analysis of the SmallSat spacecraft: From identification to design
Detroux, Thibaut ULg; Noël, Jean-Philippe ULg; Masset, Luc ULg et al

Conference (2016, September)

The objective of the present contribution is to introduce nonlinear experimental and numerical tools and methods applicable to real-life structures. The study is illustrated using the SmallSat spacecraft ... [more ▼]

The objective of the present contribution is to introduce nonlinear experimental and numerical tools and methods applicable to real-life structures. The study is illustrated using the SmallSat spacecraft developed by Airbus Defence and Space, which possesses several localized nonlinearities. The computation of nonlinear normal modes and bifurcations reveals that the satellite possesses complex dynamics including modal interactions, quasiperiodic oscillations and isolated resonances. [less ▲]

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See detailCrystallization and morphologies of waxes in rice bran oil
Diem Doan, Chi; Patel, Ashok R.; Danthine, Sabine ULg et al

Conference (2016, September)

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See detailPresentation of germplasm Health Unit-Gembloux
Massart, Sébastien ULg

Conference (2016, September)

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See detailIdentification of bovine methicillin resistant staphylococci from Europe, Africa and North America by colony hybridization, PCR and antibiotic sensitivity.
Ngassam Tchamba, Cyrille ULg; Thiry, Damien ULg; Bardiau, Marjorie et al

Conference (2016, September)

Mastitis is the costliest pathology in dairy cattle and staphylococci are the most prevalent bacterial mastitis pathogens worldwide. Antimicrobial treatment of mastitis has led to the selection of ... [more ▼]

Mastitis is the costliest pathology in dairy cattle and staphylococci are the most prevalent bacterial mastitis pathogens worldwide. Antimicrobial treatment of mastitis has led to the selection of resistant staphylococci, of which the Methicillin Resistant S. aureus (MRSA) are the most studied ones. Still, MR has also been described for non-aureus staphylococci (MRS) species. Bovine MRS(A) represent not only a problem in the treatment of mastitis, but also a potential hazard in public health via the inter-Staphylococcus transferability of the mobile “Staphylococcal Cassette Chromosome” (SCC) carrying the mec genes encoding MR and the zoonotic potential of some Staphylococcus species. The aim of this study is the comparison of genetic and phenotypic methods for the identification of MRS(A) isolated from bovine mastitis in European, African and North-American countries. A total of 1168 mastitis-associated staphylococci were isolated between 2005 and 2014 in Belgium, Italy, Switzerland, Senegal, Niger and Canada, and kept at -80°C until further use. Out of them, 867 isolates were identified to S. aureus while 301 isolates were non aureus staphylococci. All 1168 staphylococci were tested genetically by the dot blot hybridization assay on positively charged nylon membranes (Roche) after DNA extraction with 32P-radioactively labelled probes derived from the mecA and mecC genes and phenotypically by growth on “Chrom MRSA ID®” agar plates. Isolates positive at both or either tests were further studied by PCR targeting the same two genes and by the disk diffusion assay to oxacillin and cefoxitin. A total of 265 isolates (23%) were positive at both or either tests. Out of them, 27 S. aureus (10%) but no non-aureus (0%) tested positive both for DNA hybridization with the mecA probe and for growth on “Chrom MRSA ID®” plates. No isolate tested positive with the mecC probe. In addition, 32 S. aureus (12%) and 15 non aureus (6%) were positive with the mecA probe only and 169 S. aureus (64%) and 22 non aureus (8%) grew on “Chrom MRSA ID®” plates only. The S. aureus originate from Belgium (105), Italy (6), Canada (31), Senegal (38) and Niger (48) whereas the non-aureus originate from Belgium (25), Italy (1) and Niger (11). All of them are being tested with the PCR targeting the mecA gene and by the disk diffusion assay to oxacillin and cefoxitin. Most isolates (72%) grew on “Chrom MRSA ID®” plates only while few (18%) were positive to the hybridization with the mecA probe only. This high difference between the results of both tests could be explained by the weak specificity of phenotypic tests comparing to genetic tests. The others 10% of the isolates (S. aureus) which are positive with the two methods (dot blot hybridization and “Chrom MRSA ID®”) can be considered as MRSA mediated by the mecA gene. However, results of PCR and disk diffusion assay will confirm respectively the presence of mec genes and which of the two methods is the most suitable for identifying MRS from mastitis cases in cattle. Comparison of the results of phenotypic and genetic assays will indicate whether other variant(s) than mecA and mecC may be present in MRS. Further genetic and phenotypic studies are needed to (i) identify the non-aureus isolates to the species level; (ii) compare the MRS(A) isolated in the different countries by their biotypes, serotypes, lysotypes, and virulotypes, without forgetting their SCCmec and their clonal complex; and (iii) identify the mec gene variant present in hybridization-positive PCR-negative isolates, if any. [less ▲]

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See detailIdentification of bovine and porcine colistin-resistant mcr1-positive Escherichia coli.
Mainil, Jacques ULg; Muylaert, Adeline ULg; Saulmont, Marc et al

Conference (2016, September)

OBJECTIVE Polymyxins, especially colistin, have been used for years in veterinary medicine and were rediscovered a few years ago as last resort antibiotics in human medicine against multi-resistant Gram ... [more ▼]

OBJECTIVE Polymyxins, especially colistin, have been used for years in veterinary medicine and were rediscovered a few years ago as last resort antibiotics in human medicine against multi-resistant Gram negative bacterial pathogens. For years, only chromosome-mediated resistance to colistin was identified as a consequence of mutation(s) in lipid A-encoding genes. Recently, however, a plasmid-located gene (mcr1) was identified in Gram-negative enterobacteria and has since been found by PCR in several, but not all, bovine, human, porcine and poultry colistin-resistant Escherichia coli (Liu YY et al. Lancet Infect Dis, 2016, 16(2), 161-168; Nordmann P and Poirel L. Clin Microbiol Infect, 2016, 22, 398-400 ; Schwarz S and Johnson AP. J Antimicrob Chemother, 2016, in press, doi: 10.1093/jac/dkw274). The purpose of this study was to compare phenotypic and genetic for the detection of resistance to colistin and of the mcr1 gene in a collection of Escherichia coli isolated from different animal species and from humans. METHODS More than 3000 E. coli isolates from cattle, pigs, dogs, cats, horses, rabbits, chickens ducks and humans were tested for resistance to colistin by growing them on agar plates with 1g/ml of colistin. The Minimal Inhibitory Concentrations (MIC) of and the presence of the mcr1 gene in all growing isolates were determined using the E test® and colony hybridization assay with a mcr1 specific gene probe, respectively. The probe-positive isolates were further tested with the mcr1 gene specific PCR. RESULTS A total of 410 E. coli isolated grew on 1g/ml colistin-containing agar plates. The majority of isolates grew well, but several grew sparsely with only few isolated colonies. As determined by the E test®, MIC of 273 isolates (67%) was 1g/ml of colistin and higher; conversely, MIC of 137 isolates (33%) was lower than 1g/ml of colistin. Of those 410 E. coli isolates, 34 from pigs and bovines (9% of isolates growing on colistin-containing agar plates; 25% of isolates with MIC higher than 1g/ml) hybridized with the mcr1 gene-derived probe: 5 from pigs and 11 from bovines gave black spots (including five from the same calf), while 18 from pigs and one from bovine gave grey spots. All but one pig isolate had a MIC between 1.5 and 16 g/ml of colistin. Fifteen “black spot” probe-positive isolates tested positive with the mcr1 gene specific PCR as did 3 porcine “grey spot” probe-positive isolates, while the remaining 16 isolates repeatedly tested negative even after lowering the annealing temperature. CONCLUSION This study confirms that (i) the results of phenotypic assays for the detection of colistin resistance can not be always trusted; (ii) the mcr1 gene is not the only one mechanism of resistance to colistin; (iii) mcr1 variants may exist that can not be detected by the classical PCR. Phenotypic assays like growth on colistin-containing agar plates can still represent a first base screening assay, although the MIC determination using the E test® confirms a >1g/ml MIC for only 2 out of 3 growing isolates. Presence of mcr1 gene and putative variants (like the most recently described mcr2 gene; Xavier BB et al., Eurosurveillance, 21, 7 July 2016) in all probe-positive isolates will be confirmed after Whole Genome Sequencing that will also allow comparing the mcr1-positive plasmids and isolates from pigs and cattle to similar human E. coli isolates. Further studies should also be performed to identify the colistin resistance mechanism in mec-negative isolates. [less ▲]

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See detailEpidemiology and Molecular Variability of little cherry virus in Belgium
Tahzima, Rachid; Peusens, Gertie; Belïen, Tim et al

Conference (2016, September)

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See detailHeart Team Liege - Session Video Link
PIERARD, Luc ULg; vahanian, Alec; LANCELLOTTI, Patrizio ULg et al

Conference (2016, September)

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See detailCancer du canal anal: identification de deux sous-types distincts
Herfs, Michael ULg

Conference (2016, September)

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See detailFiber technology, rope-making, textiles and the Lochstäbe from the Aurignacian of the Swabian Jura
Conard, Nicholas; Rots, Veerle ULg

Conference (2016, September)

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See detailProduction of word stress by French speaking CLIL and non-CLIL learners of Dutch
Hiligsmann, Philippe; Rasier, Laurent ULg; Degrave, Pauline

Conference (2016, September)

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See detailNitric Oxide nightglow as a tracer of inter-hemispheric circulation: Detailed comparison with the LMD-GCM
Stiepen, Arnaud ULg; IUVS team; Gonzales-Galindo et al

Conference (2016, September)

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See detailAge-related differences in the dynamics of cortical excitability and cognitive inhibition during prolongedwakefulness
Gaggioni, Giulia ULg; Chelllappa, S.; Ly, J. et al

Conference (2016, September)

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See detailChanges in crop yields, soil organic carbon and soil nitrogen content under climate change and variable management practices"
Dumont, Benjamin ULg; Basso, Bruno; Shcherbak, Iurii et al

Conference (2016, September)

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See detailGay adoptive families: between stressors and losses. 2 contrasted cases
Messina, Roberta ULg; D'Amore, Salvatore ULg

Conference (2016, September)

Gay adoptive families are more and more present in the European context (currently the full joint adoption by same sex couples is granted in 9 European countries and 4 countries permit the step-child ... [more ▼]

Gay adoptive families are more and more present in the European context (currently the full joint adoption by same sex couples is granted in 9 European countries and 4 countries permit the step-child adoption). Despite the numerous studies on lesbian and gay parent- headed families, the current literature that has focused specifically on gay adoptive parent families remains rather limited. This research has the aim of increase the scientific knowledge on this new family form with the purpose to shed light on typical stressors experienced by parents and by children. The specificity of these families consists, among others, to be at the crossroads of two levels of complexity: being adoptive families and being LG families. Like all LG families, gay adoptive families have to face different stressors such as the lack of support by families of origin and social context, the need to hide their parenting project, the fear to not be considered parents "like the others" and the worry that their children are discriminated because of parents’ homosexuality. In addition to these stressors linked to the family structure, there is the challenge to adopt a child already marked by difficult life experiences and abandonment. The specificity of these families is the product of the difficulties encountered from the couples to became parents and of the experience of loss experienced by the child. The result of this whole meeting, is often found in parents’ strategies to face stressors and in the weight that the loss takes on for the child and in the relational dynamics of the family. Through two contrasting cases we will reflect on the possible adaptive strategies of parents and on the importance of integrating the child history in a new family story in which past, present and future come together and don’t know fractures. [less ▲]

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See detailCreating undocumented EU migrants through welfare: The case of Belgium
Lafleur, Jean-Michel ULg; Mescoli, Elsa ULg

Conference (2016, September)

In the dual context of increased Central and Eastern European migration and of the global financial and economic crisis, several Northern European Member States have implemented (or debated) reforms of ... [more ▼]

In the dual context of increased Central and Eastern European migration and of the global financial and economic crisis, several Northern European Member States have implemented (or debated) reforms of their welfare regimes to restrict access to migrants coming from other EU Member States. As the debates on the so-called “welfare tourism” are intensifying in different parts of the EU, we can observe a growing trend among Member States to use welfare policies as instruments to limit the mobility of certain EU migrants. This stance is best illustrated with Prime Minister Cameron’s demand for four-year ban on EU migrants claiming in-work benefits. In Belgium, too, EU citizens have been particularly affected by this adverse context as the Migration Office (Office des Etrangers) has intensified controls against EU residents receiving welfare benefits. With this policy, authorities have been using a restrictive interpretation of the European Directive 2004/38 that allows Member States to remove residence permits from EU citizens who represent an “unreasonable burden on state finances”. As a consequence, the number of EU citizens expelled from Belgium on a yearly basis has jumped from 343 to 2,042 between 2010 and 2014. In this paper, we propose to focus on those EU citizens who see their freedom of circulation in the EU restricted after claiming social protection in their country of residence. Relying on fieldwork conducted with Italian and Romanian migrants who experienced the removal of their residence permit, we discuss the different resilience strategies of those EU citizens faced with the legal obligation to leave: such strategies include returning to the homeland, refusing to leave, mobilizing the support of migrant organizations, introducing individual appeals, and seeking to regularize their administrative status. In particular, we shall focus on the experience of EU migrants who have decided to stay in Belgium and experience the status of an undocumented EU migrant. This peculiarity of this status is visible in three respects: 1) expulsion is not enforced by local authorities, 2) migrants continue to be able to circulate between their homeland and the country where they no longer have a residence permit, and 3) they have a possibility to regularize their status if they can demonstrate to municipal authorities that they no longer represent “a burden” on Belgium’s public finances. Overall, confronting our data to the rich literature on undocumented third country nationals, we discuss the limits of EU citizenship as experienced by those who are denied the right to free movement. This paper relies primarily on multi-sited ethnographic fieldwork (in progress) conducted with Italian and Romanian migrants in Brussels and with individuals of the same nationality who decided to leave Belgium and return to their home country after the removal of their residence permit. Additional fieldwork includes semi-directed interviews with civil society organizations, trade unions, and consular authorities. The data collection process started in May 2014 and is expected to be finished in May 2016. [less ▲]

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See detailEnzymatic interesterification for the formulation of high quality zero trans fats from rapeseed oil
Gibon, V.; Closset, S.; Maes, J. et al

Conference (2016, September)

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See detailClinically relevant optical properties of three types of intraocular lenses
Gatinel, Damien; Loicq, Jerôme ULg

Conference (2016, September)

Purpose: To experimentally compare the optical performance of three types of hydrophobic intraocular lenses (IOLs): extended depth of focus (TECNIS Symfony), bifocal (TECNIS ZMB00), and trifocal ... [more ▼]

Purpose: To experimentally compare the optical performance of three types of hydrophobic intraocular lenses (IOLs): extended depth of focus (TECNIS Symfony), bifocal (TECNIS ZMB00), and trifocal (FineVision GFree). Setting: Rothschild Foundation Paris, France - Liege Space Center Liège, Belgique Methods: Surface topography was analyzed by optical microscopy. Modulation transfer function (MTF) and spherical aberrations were determined on optical bench for variable pupil apertures and with two cornea models (0 µm and +0.28 µm). United States Air Force target imaging was analyzed for different focal points (near, intermediate, and far). Point spread function (PSF) and halos were quantified and compared. Results: All lenses presented step-like optic topography. For a pupil size of = 3 mm, distinctive MTF peaks were observed for all lenses: two peaks for the extended depth of focus and bifocal lenses with +1.75 and +4.00 diopters (D) addition, respectively, and three peaks for the trifocal lens with +1.75 and +3.50 addition for intermediate and near vision, respectively. The extended depth of focus and bifocal lens had slightly higher MTF at best focus with the +0.28 µm cornea model than with the 0 µm model, whereas the trifocal lens was likely to be more independent of the corneal spherical aberrations. Conclusions: Each lens appears to rely on light diffraction for optical performance, presenting halos with comparable intensities. For small pupil apertures, the MTF peaks for the far and intermediate focal distances of the trifocal and extended depth of focus lenses overlap, but the trifocal lens presented an additional MTF peak for the near focal points. [less ▲]

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See detailMeeting in Brackets - Devising Belgian Mental Health Policies through Inter-organisational Meetings
Thunus, Sophie ULg

Conference (2016, September)

Object: this paper analyses inter-organisational meetings held in response to a reform of the Belgian mental health care system. It proposes to shift the researcher’s attention from the instrumental ... [more ▼]

Object: this paper analyses inter-organisational meetings held in response to a reform of the Belgian mental health care system. It proposes to shift the researcher’s attention from the instrumental function attributed to meetings to the role they actually play in this reform. Aims: based on the observation that meetings frequently failed to reach their instrumental outcome, this paper first asks which other roles meetings might play and how. Second, it suggests that the concept of bracketing might be helpful in perceiving, describing and analysing the roles played by meetings. Methods: this paper relies on empirical material collected through semi-structured interviews, direct observation and documentary analyse. Excerpts from interviews and field notes of observation are used as a basis for analysing 4 specific meetings. These meetings have been selected according to their relevance to the research question of the role played by meetings and a set of criteria relating to the meeting type, participants, topic and context. Results: this paper demonstrates that, next to their instrumental function, meetings play at least three complementary roles, which are defined as expressive, representative and performative. It argues that these three roles of meetings are better understood by using the concept of bracketing in three ways: as a methodological, descriptive and analytical tool. [less ▲]

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See detailProperties of single fasteners - Ring shank nails
Mergny, Elke ULg; Sandhaas, Carmen

Conference (2016, September)

In Eurocode 5, nailed joints are designed using the Johansen model extended with the rope effect. The necessary input parameters are embedment strength fh, yield moment My and withdrawal capacity Fax. We ... [more ▼]

In Eurocode 5, nailed joints are designed using the Johansen model extended with the rope effect. The necessary input parameters are embedment strength fh, yield moment My and withdrawal capacity Fax. We can obtain these parameters by using empirical equations based on regression analysis. These equations are given by EC5, for smoothed nails. However, especially for ring shank nails, no consistent rules are given in the current version of Eurocode 5 and the values must be taken from technical documents of the single nails. The aim of this STSM was firstly to develop a database. It was based on 96 reports, mostly about ring shank nails tests, carried out for certification purposes, from 33 producers. Based on this extensive database, regression analyses have been carried out, especially the wire tension strength 𝑓𝑢, the yield moment 𝑀𝑦 and nail tension capacity 𝐹𝑡, all are direct nail proprieties. Potential benefits are more robust design models covering a large range of nails, reduced testing and simplified design equations. [less ▲]

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Peer Reviewed
See detailConclusion
Veymiers, Richard ULg

Conference (2016, September)

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See detailUtilisation of CO2 from an Industrial source for Methanol production
Font-Palma, Carolina; Douven, Sigrid ULg; Léonard, Grégoire ULg

Conference (2016, September)

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Peer Reviewed
See detailSurfactant-assisted USP deposition of WO3 electrochromic thin films on various TCO-glass substrates
Maho, Anthony ULg; Nicolay, Sylvain; Manceriu, Laura ULg et al

Conference (2016, August 31)

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