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See detailFe–Ti–V–P ore deposits associated with Proterozoic massif-type anorthosites and related rocks
Charlier, Bernard ULg; Namur, Olivier; Bolle, Olivier ULg et al

in Earth-Science Reviews (2015), 141(0), 56-81

Magmatic rocks containing economic concentrations of iron, titanium, vanadium and phosphorous are commonly associated with massif-type anorthosites and related rocks. This rock association is part of the ... [more ▼]

Magmatic rocks containing economic concentrations of iron, titanium, vanadium and phosphorous are commonly associated with massif-type anorthosites and related rocks. This rock association is part of the anorthosite–mangerite–charnockite–(rapakivi-)granite suites that are restricted to the Proterozoic. Understanding the geochemistry and emplacement mechanisms of ilmenite, magnetite and apatite ore deposits is crucial for exploration, efficient mining operations and ore processing. This review discusses the controlling factors on the grade of an ore, its mineralogy, and its major and trace element distribution. We present petrogenetic models of currently mined deposits (Lac Tio, Tellnes, Damiao) and discuss the characteristics of minor ore bodies from anorthosite provinces worldwide (Grenville, North China Craton, East European Craton, Rogaland, Laramie). Models of formation of anorthosite and related rocks are presented, as well as the nature of the possible parental magmas of the suite. A mineralogical classification of Fe–Ti ores is proposed: (1) Gabbro-noritic ilmenite ore ± apatite ± magnetite; (2) Ti-magnetite-dominated ore; (3) Nelsonite (Fe–Ti oxides + apatite); and (4) Rutile-ilmenite ore. The stability of ilmenite and magnetite is then critically reviewed and the influence of various factors, particularly oxygen fugacity and crystallization pressure, is examined. We discuss liquidus compositions of Fe–Ti oxides and the behavior of important trace elements such as Cr and V, both of which are sensitive to fO2 variations. Post-cumulus evolution of both oxides can occur due to re-equilibration with trapped liquid, re-equilibration with ferromagnesian silicates, exsolution, oxidation, reaction between ilmenite and magnetite, and metamorphic overprinting. These various processes are described and their effects on the oxide geochemistry are emphasized. Several potential ore-forming processes have been invoked and can explain the formation of huge concentration of ilmenite, ± magnetite, ± apatite. Fractional crystallization can be combined with crystal sorting and plagioclase buoyancy to produce relative enrichment of dense ore minerals. Silicate liquid immiscibility can segregate conjugate Si-rich and Fe-rich melts, the latter being enriched in Fe–Ti–P. Magma mixing can produce hybrid magmas located in a single-phase field of the phase diagram and precipitate a pure ilmenite cumulate. Alternative processes are also described, such as ejection of Fe–Ti-enriched residual melts by filter-pressing and compaction, solid-state remobilization of ilmenite in veins, and hydrothermal transport of Fe and Ti from the host anorthosite followed by concentration in veins and lenticular ore bodies. The magnetic properties of Fe–Ti ore deposits present contrasting signatures, depending on whether the natural remanent magnetization is dominated by hemo-ilmenite or multi-domain magnetite. Micro- and macro-scale deformation features of ore rocks are intimately correlated with magma emplacement, and with ballooning of the anorthosite diapir associated with gravitational sagging of dense ore bodies. Exploration perspectives show that oxide-apatite gabbronorites are interesting targets because ilmenite in these rocks is poorer in Cr and Mg, and because the Ti-resource may be combined with apatite and vanadiferous magnetite. [less ▲]

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See detailA branch-and-price algorithm for 2-period vehicle routing problems
Crama, Yves ULg; Rezaei Sadrabadi, Mahmood ULg; Van Woensel, Tom

E-print/Working paper (2015)

We consider a Vehicle Routing Problem (VRP) with deterministic orders in two periods from a set of stores. Orders in period 1 (2) can be postponed (advanced) to the other period but any diversion from the ... [more ▼]

We consider a Vehicle Routing Problem (VRP) with deterministic orders in two periods from a set of stores. Orders in period 1 (2) can be postponed (advanced) to the other period but any diversion from the initial orders incurs a penalty. From the perspective of a Logistics Service Provider (LSP), such diversions could be beneficial if savings in the routing costs outweigh the penalties. So could they be from a store's view, as the store can set a high enough penalty to compensate the diversion from its own optimal orders. In this paper, we introduce a new model where we seek a better solution for the LSP, compared to solving two independent VRPs with fixed orders, by allowing orders to be fully postponed or advanced. We apply a branch-and-price algorithm to solve this model to optimality. Many cutting-edge techniques are implemented to have an efficient branch-and-price algorithm, and two ideas to possibly improve the upper bound are tested. We draw algorithmic and managerial insights based on our test instances. [less ▲]

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See detailSartre et l'instinct de mort
Cormann, Grégory ULg

in Gyemant, Maria; Popa, Delia (Eds.) Approches phénoménologiques de l'inconscient (2015)

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See detailCompte-rendu de l'ouvrage de M. Le Blanc et P. Trudeau: La réadaptation de l'adolescent antisocial
Mathys, Cécile ULg

in Canadian Journal of Criminology & Criminal Justice = Revue Canadienne de Criminologie et de Justice Pénale (2015), 57(1),

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See detailMutation de l'image, mutation de l'intention ? L'impact des représentations architecturales
Cunin, Maxime; Yang, Maria C.; Elsen, Catherine ULg

in de Boissieu, Aurélie; Deshayes, Catherine (Eds.) Actes du colloque "Mutations du Projet - Milieux et Cultures Numériques" (2015)

Les architectes ont toujours eu recours à de multiples représentations pour générer, faire évoluer puis communiquer leurs concepts architecturaux (tant aux pairs qu’aux usagers, ou encore aux décideurs ... [more ▼]

Les architectes ont toujours eu recours à de multiples représentations pour générer, faire évoluer puis communiquer leurs concepts architecturaux (tant aux pairs qu’aux usagers, ou encore aux décideurs). Cet article envisage comment la représentation externe impacte la perception « naïve » d’une intention architecturale, les « non experts » assumant des rôles de plus fondamentaux au sein de certains mécanismes décisionnels. Comment l’image, en pleine mutation depuis l’ère du numérique, façonne-t-elle la perception des facteurs clés (ou « attributs ») d’une intention architecturale ? L’article résume les principaux résultats d’une enquête menée en ligne via l’interface « Amazon Mechanical Turk » et générant 790 échelles d’évaluation de 6 avant-projets architecturaux. Les résultats abordent l’analyse des données en regard des différentes attributs; en regard des trois types de représentation choisies et en regard enfin des inconsistances dont font preuve les architectes eux-mêmes, étant donné l’évaluation de leurs propres projets et représentations. Ils révèlent que les attributs ne sont pas équitablement propices à un transfert d’intention exclusivement graphique et que les formes plus abstraites de représentations constituent, dans certains contextes, le moyen le plus efficace pour le transfert fidèle d’une intention architecturale. [less ▲]

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See detailDes chiffres de la politique à la politique du chiffre Le cas des réformes du financement de la recherche dans les universités belge francophones.
Fallon, Catherine ULg

in Reflets et Perspectives de la Vie Economique (2015)

“Governing by numbers” is a trend on the increase in public action. Numbers tend to pervade the politico-administrative space without questioning neither the quantification processes which produce them ... [more ▼]

“Governing by numbers” is a trend on the increase in public action. Numbers tend to pervade the politico-administrative space without questioning neither the quantification processes which produce them nor the conditions of their utilization in government. And yet the use of numbers and data in political arguments contribute to transform the terms of the debate: politics can transform data and indicators, but one should not neglect how numbers affect policymaking. This article proposes as case study the analysis of some recent transformations of public research funding mechanism in universities in French speaking Belgium. It questions the systemic effects of the use of performance indicators in public management in this sector and it proposes some starting points for a discussion of their impact on the quality of the political debate. [less ▲]

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See detailComplete analytical procedure to assess the response of a frame submitted to a column loss
Huvelle, Clara; Hoang, Van Long ULg; Jaspart, Jean-Pierre ULg et al

in Engineering Structures (2015), 86

The present paper gives a global overview on recent developments performed at the University of Liege on structural robustness of buildings for the specific scenario ‘‘loss of a column’’. In particular, a ... [more ▼]

The present paper gives a global overview on recent developments performed at the University of Liege on structural robustness of buildings for the specific scenario ‘‘loss of a column’’. In particular, a complete analytical method to assess the response of a 2D frame losing statically one of its columns is presented in details. This method is based on the development of alternative load paths in the damaged structure and takes into account the couplings between the different parts of the structure which are differently affected by the column loss. Also, the validation of the developed method through comparison to experimental and numerical evidences is presented. [less ▲]

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See detailConcept et perception. Le conceptualisme en question
Gauvry, Charlotte ULg; Brisart, Robert

Book published by Olms (2015)

Introduction et traductions de textes de Bill Brewer, Tim Crane, Fred Dretske, Gareth Evans, John McDowell, Christopher Peacocke, Charles Travis et Michael Tye. Par une introduction détaillée et une ... [more ▼]

Introduction et traductions de textes de Bill Brewer, Tim Crane, Fred Dretske, Gareth Evans, John McDowell, Christopher Peacocke, Charles Travis et Michael Tye. Par une introduction détaillée et une sélection de neuf textes emblématiques traduits en français, l’enjeu de ce volume est d’introduire le lecteur francophone à l’histoire de la controverse sur le contenu conceptuel de la perception et de lui en proposer une fine compréhension par l’analyse des différents arguments mobilisés dans les deux camps. Simultanément, le volume a pour ambition de tester la longévité de ces arguments et d’interroger la place qui est dévolue à la controverse sur la scène philosophique la plus contemporaine. [less ▲]

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See detailCompte rendu de 'Mutations et déterminisme chez Bourdieu'
Saint-Amand, Denis ULg

in Lectures (2015)

En définitive, il aurait sans doute mieux valu resserrer le propos sous la forme d’un article critique qui aurait pu trouver place dans une revue spécialisée : ne se donnant par les moyens de ses trop ... [more ▼]

En définitive, il aurait sans doute mieux valu resserrer le propos sous la forme d’un article critique qui aurait pu trouver place dans une revue spécialisée : ne se donnant par les moyens de ses trop hautes ambitions, l’ouvrage se révèle trop léger en plus de se distinguer par le manque de soin apporté à sa réalisation [less ▲]

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See detailPrincipes biomécaniques pour le sport (cours ADEPS)
Schwartz, Cédric ULg

Learning material (2015)

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See detailSignes et corrections dans le P.Vat. gr. 11v - Favorinos, De exsilio
Macedo, Gabriel ULg

in Marganne, Marie-Hélène; Amato, Eugenio (Eds.) Entre papyrologie, philologie et littérature. Autour du traité "Sur l'Exil" de Favorinos d'Arles. Actes de la journée d'études, Nantes 13-11-2013 (2015)

A study of scribal practices, signs and corrections on the only known copy of Favorinos' De exsilio.

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See detailUncertainties in Models of Stellar Structure and Evolution
Noels-Grötsch, Arlette ULg; Bragaglia, Angela

in Astrophysics and Space Science Proceedings (2015), 39

Numerous physical aspects of stellar physics have been presented in Session 2 and the underlying uncertainties have been tentatively assessed. We try here to highlight some specific points raised after ... [more ▼]

Numerous physical aspects of stellar physics have been presented in Session 2 and the underlying uncertainties have been tentatively assessed. We try here to highlight some specific points raised after the talks and during the general discussion at the end of the session and eventually at the end of the workshop. A table of model uncertainties is then drawn with the help of the participants in order to give the state of the art in stellar modeling uncertainties as of July 2013. [less ▲]

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See detailLes techniques de restauration des prairies tempérées fonctionnent-elles sous les tropiques ?
Le Stradic, Soizig ULg; Buisson, Elise

in Forget, Michel-Pierre; Hossaert-McKey, Martine; Poncy, Odile (Eds.) Écologie tropicale: De l'ombre à la lumière (2015)

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See detailNeuromodulation in migraine: state of the art and perspectives.
MAGIS, Delphine ULg

in Expert review of medical devices (2015)

Migraine is a highly prevalent and disabling disease. The drugs prescribed for migraine prophylaxis can have intolerable side effects or can be ineffective. Neuromodulation techniques are increasingly ... [more ▼]

Migraine is a highly prevalent and disabling disease. The drugs prescribed for migraine prophylaxis can have intolerable side effects or can be ineffective. Neuromodulation techniques are increasingly used in neurology. Transcutaneous supraorbital nerve stimulation is effective in episodic migraine prevention, whereas vagus nerve stimulation provides interesting results in acute migraine therapy. Transcranial stimulation techniques gave variable, and sometimes contradictory, results. The visual cortex is the target of choice in migraine: studies in migraine prevention and aura acute treatment are encouraging. These noninvasive therapies appear safe with a low rate of side effects. Available studies of invasive occipital nerve stimulation in chronic migraine gave modest results; but invasive occipital nerve stimulation offers a new hope to highly disabled patients who failed to respond to any other treatment. In the future, neuromodulation will probably take an increasing place in migraine treatment, as add-on therapy or alternative to medications, especially because of its attractive safety profile. [less ▲]

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See detailConstructing Quebec and Wallonia: How Political Parties Speak about their Region
Mercenier, Heidi; Perrez, Julien ULg; Reuchamps, Min

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

Political parties are key political actors in both Quebec and Wallonia. As their foremost ambition is to govern their region, these parties clearly contribute to shaping its identity and image. This ... [more ▼]

Political parties are key political actors in both Quebec and Wallonia. As their foremost ambition is to govern their region, these parties clearly contribute to shaping its identity and image. This chapter aims at exploring how political parties in Quebec and in Wallonia speak about their region by focusing on an analysis of their electoral manifestos for the period 1994–2014. Using a quantitative and qualitative approach combining insights from lexicometry, cognitive linguistics and political science, the aims of this contribution are (i) to unravel how the parties perceive their region and its future development, (ii) to identify relevant evolutions in their perception of their respective region, and (iii) to assess to what extent parallels can be drawn between the two regions. [less ▲]

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See detailPositive cooperativity between acceptor and donor sites of the peptidoglycan glycosyltransferase.
Bury, Daniel; Dahmane, Ismahene ULg; Derouaux, Adeline ULg et al

in Biochemical pharmacology (2015), 93(2), 141-50

The glycosyltransferases of family 51 (GT51) catalyze the polymerization of lipid II to form linear glycan chains, which, after cross linking by the transpeptidases, form the net-like peptidoglycan ... [more ▼]

The glycosyltransferases of family 51 (GT51) catalyze the polymerization of lipid II to form linear glycan chains, which, after cross linking by the transpeptidases, form the net-like peptidoglycan macromolecule. The essential function of the GT makes it an attractive antimicrobial target; therefore a better understanding of its function and its mechanism of interaction with substrates could help in the design and the development of new antibiotics. In this work, we have used a surface plasmon resonance Biacore((R)) biosensor, based on an amine derivative of moenomycin A immobilized on a sensor chip surface, to investigate the mechanism of binding of substrate analogous inhibitors to the GT. Addition of increasing concentrations of moenomycin A to the Staphylococcus aureus MtgA led to reduced binding of the protein to the sensor chip as expected. Remarkably, in the presence of low concentrations of the most active disaccharide inhibitors, binding of MtgA to immobilized moenomycin A was found to increase; in contrast competition with moenomycin A occurred only at high concentrations. This finding suggests that at low concentrations, the lipid II analogs bind to the acceptor site and induce a cooperative binding of moenomycin A to the donor site. Our results constitute the first indication of the existence of a positive cooperativity between the acceptor and the donor sites of peptidoglycan GTs. In addition, our study indicates that a modification of two residues (L119N and F120S) within the hydrophobic region of MtgA can yield monodisperse forms of the protein with apparently no change in its secondary structure content, but this is at the expense of the enzyme function. [less ▲]

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See detailOptimal control of a Cope rearrangement by coupling the reaction path to a dissipative bath or a second active mode
Chenel, Aurélie; Meier, Christoph; Dive, Georges et al

in The Journal of Chimical Physics (2015), 142

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See detailInvesting in the Future
Pahud de Mortanges, Charles ULg

E-print/Working paper (2015)

This paper attempts to address the challenges of how to invest in Synthetic Biology firms, most of which are relatively new start-ups and unprofitable. Valuing an early-stage firm with only a brief ... [more ▼]

This paper attempts to address the challenges of how to invest in Synthetic Biology firms, most of which are relatively new start-ups and unprofitable. Valuing an early-stage firm with only a brief operating history, little or no operating profit (or even revenue), and an immature and untested business model, could be a formidable challenge. We propose a limited number of quantitative, and a larger number of qualitative criteria. An investor may consider these when faced with analyzing a new untried business, but one he/she believes has considerable potential for success in the future. [less ▲]

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See detailElevated heart rate at 24-36h after admission and in-hospital mortality in acute in non-arrhythmic heart failure.
Lancellotti, Patrizio ULg; ANCION, Arnaud ULg; Magne, Julien et al

in International journal of cardiology (2015), 182C

BACKGROUND: Elevated resting heart rate is associated with worse outcomes in chronic heart failure (HF) but little is known about its prognostic impact in acute setting. The main aim of the present study ... [more ▼]

BACKGROUND: Elevated resting heart rate is associated with worse outcomes in chronic heart failure (HF) but little is known about its prognostic impact in acute setting. The main aim of the present study was to examine the relationship between resting heart rate obtained 24-36h after admission for acute non-arrhythmic HF and in-hospital mortality. METHODS AND RESULTS: We examined the association of heart rate with in-hospital mortality in a cohort of 712 patients admitted for acute HF. None of the patients had significant arrhythmias, required invasive ventilation, or presented with acute coronary syndrome or primary valvular disease. Forty patients (5.6%) died during the hospital stay. Those patients were significantly older (78+/-9 vs. 72+/-12years; p=0.0021), had higher heart rate (92+/-22 vs. 78+/-18bpm; p<0.0001), NT pro-BNP (p=0.0005), creatinine (p=0.023), were often diabetics (p=0.026) and had lower systolic and diastolic blood pressures (p<0.05). There was a significant graded relationship between the increase in mortality rate and tertile of heart rate (p<0.01). With multivariable analysis, age (p=0.037), heart rate (p<0.0001), diastolic blood pressure (p<0.001), prior ischemic heart disease (p=0.02) and creatinine (p=0.019) emerged as independent predictors of in-hospital mortality. After adjusting for predictors of poor prognosis, patients in the highest heart rate tertile had worst outcomes when compared with those in the lowest heart rate group (p=0.007). CONCLUSIONS: Higher heart rate 24-36h after admission for acute non-arrhythmic HF is associated with increased risk of in-hospital mortality. Early targeting of elevated heart rate might represent a complementary therapeutic challenge. [less ▲]

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