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See detail“Rhizoponics”: a novel hydroponic rhizotron for root system analyses on mature Arabidopsis thaliana plants
Mathieu, Laura ULg; Lobet, Guillaume ULg; Tocquin, Pierre ULg et al

in Plant Methods (2015), 11

We present here an innovative design of hydroponic rhizotrons (rhizoponics) adapted to Arabidopsis thaliana. The setup allows to simultaneously characterize the RSA and shoot development from seedling to ... [more ▼]

We present here an innovative design of hydroponic rhizotrons (rhizoponics) adapted to Arabidopsis thaliana. The setup allows to simultaneously characterize the RSA and shoot development from seedling to adult stages, i.e. from seed to seed. This system offers the advantages of hydroponics such as control of root environment and easy access to the roots for measurements or sampling. Being completely movable and low cost, it can be used in controlled cabinets. We chose the case of cadmium treatment to illustrate potential applications, from cell to organ levels. [less ▲]

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See detailG. Genette et la rhétorique : aide mémoire
Lorent, Fanny ULg

in Atelier de théorie littéraire de Fabula (2015)

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See detailExperimental astrochemistry: from ground-based to space-borne laboratories (Foreword)
De Becker, Michaël ULg; Cottin, Hervé; Fleury-Frenette, Karl ULg et al

in Bulletin de la Société Royale des Sciences de Liège (2015, January), 84(4-6),

The investigation of the origin and evolution of molecules in space environments, either in interstellar or interplanetary conditions, constitutes a topic of high importance in modern space sciences. The ... [more ▼]

The investigation of the origin and evolution of molecules in space environments, either in interstellar or interplanetary conditions, constitutes a topic of high importance in modern space sciences. The presence of diversified and complex molecules motivates astrochemists to explore their formation mechanisms along with the physical conditions ruling these physico-chemical processes. Beside theoretical approaches aiming at simulating these processes, experimental techniques are nowadays frequently applied. Both laboratory and space experiment projects allow to reproduce to some extent the adequate conditions to understand some of these processes. The most recent results based on these techniques, and the prospects for future investigations, including the use of space platforms, were the scientific motivation of this workshop. These proceedings summarize a part of the content of this workshop, including abundant references to the relevant bibliography. [less ▲]

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See detailMassive stars: privileged sources of cosmic-rays for interstellar astrochemistry
De Becker, Michaël ULg

in Bulletin de la Société Royale des Sciences de Liège (2015, January), 84

Massive stars can be considered as crucial engines for interstellar physics. They are indeed the main providers of UV radiation field, and constitute a substantial source of chemical enrichment. On their ... [more ▼]

Massive stars can be considered as crucial engines for interstellar physics. They are indeed the main providers of UV radiation field, and constitute a substantial source of chemical enrichment. On their evolution time-scale (at most about 10 Myr), they typically stay close to their formation site, i.e. close to molecular clouds very rich in interstellar molecules. These stellar objects have also the property to be involved in particle acceleration processes leading to the production of high energy charged particles (cosmic-rays). After rejection in the interstellar medium, these particles will play a substantial role in processes such as those simulated in various facilities dedicated to experimental astrochemistry. This short contribution intends to put these particles, crucial for astrochemistry, in their adequate astrophysical context. [less ▲]

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See detailThe impact of transport policies on railroad intermodal freight competitiveness – The case of Belgium
Santos, Bruno F.; Limbourg, Sabine ULg; Carreira, Joana Silva

in Transportation Research. Part D : Transport and Environment (2015), 34

This paper discusses the impact of three freight transport policies aiming to promote railroad intermodal transport in Europe, and examines the case of Belgium as a testing ground. These policies consist ... [more ▼]

This paper discusses the impact of three freight transport policies aiming to promote railroad intermodal transport in Europe, and examines the case of Belgium as a testing ground. These policies consist in subsidizing intermodal transport operations (such as in Belgium, to stimulate rail transport), internalizing external costs (as recommended by the European Union in order to foster cleaner modes), and adopting a system perspective when optimizing the location of inland intermodal terminals. The study proposes an innovative mixed integer intermodal freight location-allocation model based on hub-location theory and deals with non-linear transport costs in order to replicate economies of distance. Our analysis suggests that subsidizing has a significant impact on the volumes transported by intermodal transport, and, to a lesser extent, that optimizing terminal location increases the competitiveness of intermodal transport. On the other hand, according to our assumptions, internalizing external costs can negatively impact the promotion of intermodality. This finding indicates that innovative last-mile transports are needed in order to reduce the external impacts of drayage operations. [less ▲]

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See detailCircadian and circannual variations in cord blood hematopoietic cell composition
Servais, Sophie ULg; BAUDOUX, Etienne ULg; Brichard, B. et al

in Haematologica (2015), 100(1), 32-34

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See detailStephen Jay Gould ou la science enchantée
Jacquemain, Marc ULg

in Politique : Revue de Débats (2015), 88

Stephen Jay Gould, inventeur de la "théorie des équilibres ponctués" avec Nils Elredge fut non seulement un paléontologue de premier plan mais aussi un défenseur acharné du darwinisme. Défenseur acharné ... [more ▼]

Stephen Jay Gould, inventeur de la "théorie des équilibres ponctués" avec Nils Elredge fut non seulement un paléontologue de premier plan mais aussi un défenseur acharné du darwinisme. Défenseur acharné, mais dénué de tout dogmatisme il s'est aussi battu pour une conception "humaniste" de la science, qui l'éloigne de tout scientisme et qui l'amène souvent à "réhabiliter les vaincus" de l'histoire des sciences. Enfin, s'il fut un défenseur de Darwin, il a combattu ceux de successeurs qui ont essayé de l'utiliser pour défendre l'inégalité sociale ou l'eugénisme. En cela Gould fut sans doute le meilleur des darwiniens. [less ▲]

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See detailThree-Parameter Kinematic Theory for Shear Behavior of Continuous Deep Beams
Mihaylov, Boyan ULg; Hunt, Bradley; Bentz, Evan et al

in ACI Structural Journal (2015), 112(1), 47-57

This paper presents a theory for predicting shear strengths, deformations, and crack widths near failure of continuous deep beams. To describe the deformations in continuous deep beams, the theory uses a ... [more ▼]

This paper presents a theory for predicting shear strengths, deformations, and crack widths near failure of continuous deep beams. To describe the deformations in continuous deep beams, the theory uses a three-degree-of-freedom kinematic model (3PKT), which is an extension of an earlier two-degree-of-freedom model (2PKT) for members in single curvature. The extended model is validated with the help of measured local and global deformations taken during loading to failure of a large continuous deep beam. The accuracy of the shear-strength predictions given by the theory is evaluated using a database of 129 published tests of continuous deep beams. The theory enables the load distribution and failure loads of continuous deep beams subject to differential settlement to be evaluated. [less ▲]

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See detailCompte-rendu de l'ouvrage d'Eva Illouz : "Hard Romance : "Cinquante nuances de Grey" et nous" (2014)
Ledent, David ULg

in COnTEXTES : Revue de Sociologie de la Littérature (2015)

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See detailModelling Hydromechanical Dilation Geomaterial—Cavitation and Localization
Sieffert, Y.; Buzzi, O.; Collin, Frédéric ULg et al

in Chau, Kam Tim; Zhao, Jidong (Eds.) Bifurcation and Degradation of Geomaterials in the New Millennium (2015, January)

This paper presents an extension of the local second gradient model to multiphasic materials (solid particles, air, water) and including the cavitation phenomenon. This new development was made in order ... [more ▼]

This paper presents an extension of the local second gradient model to multiphasic materials (solid particles, air, water) and including the cavitation phenomenon. This new development was made in order to model the response of saturated dilatant materials under deviatoric stress and undrained conditions and possibly, in future, the behaviour of unsaturated soils [less ▲]

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See detailSEM and EDS observations of carrollite bioleaching with a mixed culture of acidophilic bacteria
Nkulu, Guy; Gaydardzhiev, Stoyan ULg; Mwema, Edouard et al

in Minerals Engineering (2015), doi:10.1016/j.mineng.2014.12.005

Bioleaching of high purity carrollite minerals with mesophilic bacteria was carried out and monitored by observations in scanning electron microscopy (SEM) and elemental X-ray microanalysis (EDS) to ... [more ▼]

Bioleaching of high purity carrollite minerals with mesophilic bacteria was carried out and monitored by observations in scanning electron microscopy (SEM) and elemental X-ray microanalysis (EDS) to provide evidence of the interaction pattern between carrollite and microorganisms. A bacterial consortium involving three different acidophilic chemolithotrophs was adopted. The evolution of the surface topography, inside alteration effects and elemental composition of the mineral with leaching time was followed. It could be postulated that bacterial adhesion takes place on the mineral surface, resulting in the formation of dissolution pits of various shapes and continues by boring elongated channels deep inside the mineral grains. Enhanced concentration of ferric iron and sulphur could be assumed in vicinity of the zones where mineralized polymer substances are precipitated. It could be inferred that carrollite dissolution is governed by cooperative bioleaching involving oxidation induced by bacteria attached to the surface and ferric iron re-oxidized by planktonic bacteria in suspension. [less ▲]

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See detailPossibilities for Co(III) dissolution from an oxidized ore through simultaneous bioleaching of pyrite
Zeka, Leon; Lambert, Fanny ULg; Frenay, Jean ULg et al

in Minerals Engineering (2015)

Solubilisation of Co(III) from a heterogenite met in copper cobaltiferous oxide ore has been realized through reductive leaching using ferrous iron generated via bio-oxidation of pyrite. Biotic and ... [more ▼]

Solubilisation of Co(III) from a heterogenite met in copper cobaltiferous oxide ore has been realized through reductive leaching using ferrous iron generated via bio-oxidation of pyrite. Biotic and abiotic experiments at various pulp densities and redox potentials have been performed and results compared. Cobalt leaching at elevated redox potential is possible, offering cost reduction benefits due to reduced consumption of ferrous iron. At elevated potential of 625 mV, however, the initial rate of cobalt leaching has been found as 115 mg/(g ore)⋅(24 h), lower than the rate of 865 mg/(g ore)⋅(24 h) registered at 505 mV. Less stochiometric amount of ferrous iron was required when cobalt leaching was coupled to pyrite bioleaching, with 75% of cobalt recovered for 12 h at the optimally found conditions. It could be inferred that the Fe3+–Fe2+ cycle exists and is efficiently maintained through bacterial presence in the studied system. [less ▲]

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See detail1, 2, 3 façons d’évaluer des travaux pratiques d’Histologie
Multon, Sylvie ULg; Crahay, Vinciane ULg; Florquin, Sandra et al

Conference (2015, January)

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See detail18F-FDG PET Uptake Characterization Through Texture Analysis: Investigating the Complementary Nature of Heterogeneite and Functional Tumor Volume in a Multi-Cancer Site Patient Cohort
HATT, MAT; MAJDOUB, MOHAMED; VALLIERES, MARTIN et al

in Journal of Nuclear Medicine (The) (2015), 56(1), 38-44

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See detailCareer Patterns in Multi-level Quebec and Wallonia: Towards a Sub-State and Federal Political Class?
Dodeigne, Jérémy ULg

in Reuchamps, Min (Ed.) Minority Nations in Multinational Federations: A comparative study of Quebec and Wallonia (2015)

The process of regionalisation in Western Europe has renewed the interest in political careers, not only for newly regionalised unitary states but also for established federations (Stolz 2003). Recently ... [more ▼]

The process of regionalisation in Western Europe has renewed the interest in political careers, not only for newly regionalised unitary states but also for established federations (Stolz 2003). Recently, Docherty (2011: 186) rightly stated that “there has been little analytical work on the Canadian political career ” . And, arguably, even less on political careers in Quebec. Though, since the end of the 1990s, Walloon political careers have received greater attention (Fiers 2001a, 2001b; Pilet, Fiers and Steyvers 2007; Vanlangenakker, Maddens and Put 2010). Based on an original dataset, this chapter proposes a comprehensive analyses of federal and regional careers since the 1990s in Quebec and in Wallonia. More specifically, it presents and explains the circulation of members of parliament (MPs) in the two federations, with a specific focus on career maintenance at a single level of government (professional political careers) and career advancement (level-hopping movements between political arenas). [less ▲]

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See detailA plastic-damage model for concrete in fire: Applications in structural fire engineering
Gernay, Thomas ULg; Franssen, Jean-Marc ULg

in Fire Safety Journal (2015), 71

The research aims at developing a new multiaxial constitutive model for concrete in the fire situation. In addition to validity at the material level, a crucial feature of a constitutive model is the ... [more ▼]

The research aims at developing a new multiaxial constitutive model for concrete in the fire situation. In addition to validity at the material level, a crucial feature of a constitutive model is the applicability at the structural level; yet for concrete in fire there remains a serious lack of models combining reliability and robustness. The theoretical aspects and validation of the new model, which rely on a plastic-damage formulation, have been the subject of a former publication; they are briefly summarized here. This paper explores the capabilities of the concrete model for being used in a performance-based structural fire engineering framework. Several examples of numerical simulations by non-linear finite element method are discussed, with emphasis on practical applications that are demanding for the material model. In particular, it is shown that the simulations using the new concrete model succeed in capturing, at ambient temperature, the crack pattern in a plain concrete specimen and the influence of the loading path on reinforced concrete (RC) slabs. At high temperature, the presented applications include a RC slab subjected to furnace fire and a large-scale composite steel–concrete structure subjected to natural fire. In the numerical analyses, no parameter calibration was required on the particular concrete type, except for the uniaxial strengths and tensile crack energy which are to be defined case-by-case. The results illustrate the reliability and numerical robustness of the model. Also, they suggest that satisfactory prediction of structural behavior in fire can be obtained when no additional data is available on the specific properties of the particular concrete mix that is used in the project, as is often the case in practice, by using standard values of parameters. [less ▲]

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See detailMultiscale modelling framework for the fracture of thin brittle polycrystalline films - Application to polysilicon
Mulay, Shantanu; Becker, Gauthier ULg; Vayrette, Renaud et al

in Computational Mechanics (2015), 55(1), 73-91

Micro-electro-mechanical systems (MEMS) made of polycrystalline silicon are widely used in several engineering fields. The fracture properties of polycrystalline silicon directly affect their reliability ... [more ▼]

Micro-electro-mechanical systems (MEMS) made of polycrystalline silicon are widely used in several engineering fields. The fracture properties of polycrystalline silicon directly affect their reliability. The effect of the orientation of grains on the fracture behaviour of polycrystalline silicon is investigated out of the several factors. This is achieved, firstly, by identifying the statistical variation of the fracture strength and critical strain energy release rate, at the nanoscopic scale, over a thin freestanding polycrystalline silicon film, having mesoscopic scale dimensions. The fracture stress and strain at the mesoscopic level are found to be closely matching with uniaxial tension experimental results. Secondly, the polycrystalline silicon film is considered at the continuum MEMS scale, and its fracture behaviour is studied by incorporating the nanoscopic scale effect of grain orientation. The entire modelling and simulation of the thin film is achieved by combining the discontinuous Galerkin method and extrinsic cohesive law describing the fracture process. [less ▲]

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