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See detailThe X-ray properties of magnetic massive stars
Nazé, Yaël ULg; Petit, Véronique; Rinbrand, Melanie et al

in IAU Symposium (2015, January 01)

Early-type stars are well-known to be sources of soft X-rays. However, this high-energy emission can be supplemented by bright and hard X-rays when magnetically confined winds are present. In an attempt ... [more ▼]

Early-type stars are well-known to be sources of soft X-rays. However, this high-energy emission can be supplemented by bright and hard X-rays when magnetically confined winds are present. In an attempt to clarify the systematics of the observed X-ray properties of this phenomenon, a large series of Chandra and XMM observations was analyzed, over 100 exposures of 60% of the known magnetic massive stars listed recently by Petit et al. (2013). It is found that the X-ray luminosity is strongly correlated with mass-loss rate, in agreement with predictions of magnetically confined wind models, though the predictions of higher temperature are not always verified. We also investigated the behaviour of other X-ray properties (absorption, variability), yielding additional constraints on models. This work not only advances our knowledge of the X-ray emission of massive stars, but also suggests new observational and theoretical avenues to further explore magnetically confined winds. [less ▲]

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See detailFood provioning influences ranging patterns in northern pigtailed macaques (Macaca leonina)
Huynen, Marie-Claude ULg; Savini, Tommaso ULg; Asensio, Norberto et al

in International Journal of Primatology (2015, January)

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See detailDocumentário e mal-entendido. Retorno sobre uma primeira filmagem no Brasil
Hamers, Jérémy ULg

in Stols, Eddy; Mascaro, Luciana; Bueno, Clodoaldo (Eds.) Brasil e Bélgica: Cinco Séculos de Conexões e Interação (2015)

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See detailDiversité des expressions culturelles: retour du politique
Vlassis, Antonios ULg

Report (2015)

Cette édition spéciale aborde les enjeux actuels de la mise en œuvre de la Convention sur la diversité des expressions culturelles (CDEC) à travers une analyse des questions discutées lors de la 8ème ... [more ▼]

Cette édition spéciale aborde les enjeux actuels de la mise en œuvre de la Convention sur la diversité des expressions culturelles (CDEC) à travers une analyse des questions discutées lors de la 8ème session du Comité intergouvernemental de la CDEC. À cet égard, nous revenons dans un premier temps sur l’impact normatif de la CDEC et sur la question des rapports périodiques des Parties à la CDEC. Dans un deuxième temps, nous traitons du débat autour de la mise en œuvre du Fonds international pour la diversité culturelle et des articles 16 (Traitement préférentiel) et 21 (Concertation et coordination internationales), ainsi que de la question de l’adaptation de la CDEC aux défis des technologies numériques. Les interventions des participants lors de la session du Comité et le caractère du débat nous révèlent le retour du politique dans la CDEC, à savoir que l’étape actuelle de sa mise en œuvre implique nécessairement des divergences et des conflits politiques, vu l’importance économique, sociale et culturelle des questions traitées. Un tableau récapitulatif des principaux événements qui ont marqué 2014 vient compléter ce tour d’horizon. [less ▲]

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See detailMetabolic reprogramming in transformed mouse cortical astrocytes: a proteomic study.
Bentaib, Azeddine; De Tullio, Pascal ULg; Chneiweiss, Herve et al

in Journal of proteomics (2015), 113

Metabolic reprogramming is thought to play a key role in sustaining the survival and proliferation of cancer cells. These changes facilitate for example the uptake and release of nutrients required for ... [more ▼]

Metabolic reprogramming is thought to play a key role in sustaining the survival and proliferation of cancer cells. These changes facilitate for example the uptake and release of nutrients required for nucleotide, protein and lipid synthesis necessary for macromolecule assembly and tumor growth. We applied a 2D-DIGE (Two-Dimensional Differential in-Gel Electrophoresis) quantitative proteomic analysis to characterize the proteomes of mouse astrocytes that underwent in vitro cancerous transformation, and of their normal counterparts. Metabolic reprogramming effects on enzymatic and structural protein expression as well as associated metabolites abundance were quantified. Using enzymatic activity measurements and zymography, we documented and confirmed several changes in abundance and activity of various isoenzymes likely to participate in metabolic reprogramming. We found that after transformation, the cells increase their expression of glycolytic enzymes, thus augmenting their ability to use aerobic glycolysis (Warburg effect). An increased capacity to dispose of reducing equivalents through lactate production was also documented. Major effects on carbohydrates, amino acids and nucleotides metabolic enzymes were also observed. Conversely, the transformed cells reduced their enzymatic capacity for reactions of tricarboxylic acid oxidation, for neurotransmitter (glutamate) metabolism, for oxidative stress defense and their expression of astroglial markers. BIOLOGICAL SIGNIFICANCE: The use of a global approach based on a 2D DIGE analysis allows obtaining a comprehensive view of the metabolic reprogramming undergone by astrocytes upon cancerous transformation. Indeed, except for a few enzymes such as pyruvate carboxylase and glutaminase that were not detected in our initial analysis, pertinent information on the abundance of most enzymes belonging to pathways relevant to metabolic reprogramming was directly obtained. In this in vitro model, transformation causes major losses of astrocyte-specific proteins and functions and the acquisition of metabolic adaptations that favor intermediate metabolites production for increased macromolecule biosynthesis. Thus our approach appears to be readily applicable for the investigation of changes in protein abundance that determine various transformed cell phenotypes. It could similarly be applied to the evaluation of the effects of treatments aimed at correcting the consequences of cell transformation. [less ▲]

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See detailChine, une mise à jour
Florence, Eric ULg

in Politique : Revue de Débats (2015), 88

Au lendemain de la répression du mouvement démocratique de 1989, journalistes, analystes et autres « China watchers » abondaient en commentaires crépusculaires sur la pérennité du régime chinois ... [more ▼]

Au lendemain de la répression du mouvement démocratique de 1989, journalistes, analystes et autres « China watchers » abondaient en commentaires crépusculaires sur la pérennité du régime chinois. L’argument le plus souvent évoqué était celui d’un décalage insoutenable entre réformes économiques – qui connaîtront un approfondissement à l’occasion du fameux « voyage dans le Sud » de Deng Xiaoping en 1992 – et l’absence de réformes politiques, un décalage qui devait presque immanquablement signifier la fin du régime communiste. Quelque vingt-cinq ans plus tard, où en est-on ? [less ▲]

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See detailEffect of stress path on the miniaturization size effect for nickel polycrystals
Keller, Clement; Hug, Eric; Habraken, Anne ULg et al

in International Journal of Plasticity (2015), 64

The mechanical behavior of metallic materials deeply depends on the size of samples. For specimen dimensions decreasing from a few millimeters to a few micrometers, the general observed trend is a ... [more ▼]

The mechanical behavior of metallic materials deeply depends on the size of samples. For specimen dimensions decreasing from a few millimeters to a few micrometers, the general observed trend is a softening of the mechanical behavior in tension which affects the stress level and the strain hardening. The objective of this work is to provide new experimental results in order to analyze the miniaturization size effects for various stress paths without strain gradients across the thickness of the samples. To this aim, experimental tensile tests, large tensile tests and shear tests have been performed on Ni sheets with various grain sizes. Results show that the miniaturization softening is affected by triaxiality, the larger is this parameter, the lower is the mechanical softening. These features seem to be linked to surface effects which are larger for low triaxiality stress paths. From an industrial point of view, it is hence possible to improve the forming of microparts using suitable stress paths. [less ▲]

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See detailStimuli-responsive behavior of micelles prepared from a poly(vinyl alcohol)-block-poly(acrylic acid)-block-poly(4-vinylpyridine) triblock terpolymer
Poggi, Elio; Guerlain, Claire; Debuigne, Antoine ULg et al

in European Polymer Journal (2015), 62

A poly(vinyl alcohol)-block-poly(acrylic acid)-block-poly(4-vinylpyridine) triblock terpolymer (PVOH-b-PAA-b-P4VP) is prepared by hydrolyzing a poly(vinyl acetate)-block-poly(acrylonitrile)-block-poly(4 ... [more ▼]

A poly(vinyl alcohol)-block-poly(acrylic acid)-block-poly(4-vinylpyridine) triblock terpolymer (PVOH-b-PAA-b-P4VP) is prepared by hydrolyzing a poly(vinyl acetate)-block-poly(acrylonitrile)-block-poly(4-vinylpyridine) precursor (PVAc-b-PAN-b-P4VP) synthesized by a combination of cobalt-mediated radical polymerization (CMRP) and nitroxide mediated polymerization (NMP). The PVOH-b-PAA-b-P4VP terpolymer is further micellized in water and the accordingly obtained micellar structures are characterized by a combination of dynamic light scattering (DLS) and cryo-transmission electron microscopy (cryo-TEM) as a function of pH. Well-defined micelles are observed in the whole pH range except for pH values below 4.5 where non-aggregated chains (unimers) are present. The formation of micelles can be rationalized by the formation of insoluble PAA/P4VP inter-polyelectrolyte complexes in the 4.5–6 pH range while hydrophobic P4VP cores are observed at pH values above 6. Finally, the effect of the addition of different salts on the micellar characteristic features is investigated. [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 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 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 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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