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See detailAre the stars of a new class of variability detected in NGC 3766 fast rotating SPB stars?
Salmon, Sébastien ULg; Montalbán, J.; Reese, D. R. et al

in Meynet, Georges; Georgy, Cyril; Groh, Jose (Eds.) et al Proceedings of the International Astronomical Union S307 (2015, January 01)

A recent photometric survey in the NGC 3766 cluster led to the detection of stars presenting an unexpected variability. They lie in a region of the Hertzsprung-Russell (HR) diagram where no pulsation are ... [more ▼]

A recent photometric survey in the NGC 3766 cluster led to the detection of stars presenting an unexpected variability. They lie in a region of the Hertzsprung-Russell (HR) diagram where no pulsation are theoretically expected, in between the δ Scuti and slowly pulsating B (SPB) star instability domains. Their variability periods, between ~0.1-0.7 d, are outside the expected domains of these well-known pulsators. The NCG 3766 cluster is known to host fast rotating stars. Rotation can significantly affect the pulsation properties of stars and alter their apparent luminosity through gravity darkening. Therefore we inspect if the new variable stars could correspond to fast rotating SPB stars. We carry out instability and visibility analysis of SPB pulsation modes within the frame of the traditional approximation. The effects of gravity darkening on typical SPB models are next studied. We find that at the red border of the SPB instability strip, prograde sectoral (PS) modes are preferentially excited, with periods shifted in the 0.2-0.5 d range due to the Coriolis effect. These modes are best seen when the star is seen equator-on. For such inclinations, low-mass SPB models can appear fainter due to gravity darkening and as if they were located between the δ Scuti and SPB instability strips. [less ▲]

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See detailAsteroseismology of Massive Stars: Some Words of Caution
Noels-Grötsch, Arlette ULg; Godart, M.; Salmon, Sébastien ULg et al

in Meynet, Georges; Georgy, Cyril; Groh, Jose (Eds.) et al Proceedings of the International Astronomical Union S307 (2015, January 01)

Although playing a key role in the understanding of the supernova phenomenon, the evolution of massive stars still suffers from uncertainties in their structure, even during their ``quiet'' main sequence ... [more ▼]

Although playing a key role in the understanding of the supernova phenomenon, the evolution of massive stars still suffers from uncertainties in their structure, even during their ``quiet'' main sequence phase and later on during their subgiant and helium burning phases. What is the extent of the mixed central region? In the local mixing length theory (LMLT) frame, are there structural differences using Schwarzschild or Ledoux convection criterion? Where are located the convective zone boundaries? Are there intermediate convection zones during MS and post-MS phase, and what is their extent and location? We discuss these points and show how asteroseismology could bring some light on these questions. [less ▲]

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See detailIs λ Cep a pulsating star?
Uuh-Sonda, J. M.; Eenens, P.; Rauw, Grégor ULg

in Meynet, Georges; Georgy, Cyril; Groh, José (Eds.) et al IAU Symposium (2015, January 01)

It has been proposed that the variability seen in absorption lines of the O6Ief star λ Cep is periodical and due to non-radial pulsations (NRP). We have obtained new spectra during six campaigns lasting ... [more ▼]

It has been proposed that the variability seen in absorption lines of the O6Ief star λ Cep is periodical and due to non-radial pulsations (NRP). We have obtained new spectra during six campaigns lasting between five and nine nights. In some datasets we find recurrent spectral variations which move redward in the absorption line profile, consistent with perturbations on the stellar surface of a rotating star. However the periods found are not stable between datasets, at odds with the NRP hypothesis. Moreover, even when no redward trend is found in a full dataset of an observing campaign, it can be present in a subset, suggesting that the phenomenon is short-lived, of the order of a few days, and possibly linked to transient magnetic loops. [less ▲]

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See detailSupraglacial lakes on the Greenland ice sheet advance inland under warming climate
Leeson, A.; Shepherd, A.; Briggs, K. et al

in Nature Climate Change (2015), 5

Supraglacial lakes (SGLs) form annually on the Greenland ice sheet and, when they drain, their discharge enhances ice-sheet flow by lubricating the base and potentially by warming the ice. Today, SGLs ... [more ▼]

Supraglacial lakes (SGLs) form annually on the Greenland ice sheet and, when they drain, their discharge enhances ice-sheet flow by lubricating the base and potentially by warming the ice. Today, SGLs tend to form within the ablation zone, where enhanced lubrication is offset by efficient subglacial drainage. However, it is not clear what impact a warming climate will have on this arrangement. Here, we use an SGL initiation and growth model to show that lakes form at higher altitudes as temperatures rise, consistent with satellite observations. Our simulations show that in southwest Greenland, SGLs spread 103 and 110 km further inland by the year 2060 under moderate (RCP 4.5) and extreme (RCP 8.5) climate change scenarios, respectively, leading to an estimated 48–53% increase in the area over which they are distributed across the ice sheet as a whole. Up to half of these new lakes may be large enough to drain, potentially delivering water and heat to the ice-sheet base in regions where subglacial drainage is inefficient. In such places, ice flow responds positively to increases in surface water delivered to the bed through enhanced basal lubrication and warming of the ice, and so the inland advance of SGLs should be considered in projections of ice-sheet change. [less ▲]

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See detailConstruire des savoirs sur l'activité de lecture afin de développer les compétences des élèves en difficulté : l'inaccessible rêve?
De Croix, Séverine ULg; Ledur, Dominique

in Education & Formation (2015), e-302

De nombreux jeunes adolescents faibles lecteurs se méprennent sur la nature de l’activité de lecture et souffrent d’un déficit métacognitif qui les empêche d’autoréguler leur activité de compréhension. La ... [more ▼]

De nombreux jeunes adolescents faibles lecteurs se méprennent sur la nature de l’activité de lecture et souffrent d’un déficit métacognitif qui les empêche d’autoréguler leur activité de compréhension. La réflexion qui suit s’inscrit dans le cadre des travaux relatifs aux enseignements adaptés à la prise en charge de ces déficits. Des dispositifs visant à développer la métacognition en lecture, à construire des savoirs sur cette activité et à mieux se percevoir en tant que lecteur ont été conçus, expérimentés et analysés dans le cadre d’une recherche-action longitudinale de type qualitatif. Cet article décrit quelques effets de ces dispositifs, qui encouragent à poursuivre sur la voie de ces interventions à dimension métacognitive dans des recherches à plus large échelle. [less ▲]

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See detailL'adolescent diabétique et la tentation suicidaire
Malchair, Alain ULg

Poster (2015, January)

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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 detailManufacturing of Kivuguto milk and stability in storage under refrigeration
Karenzi, Eugène; Fauconnier, Marie-Laure ULg; Destain, Jacqueline ULg et al

in European Scientific Journal (2015), 11(3), 1-16

The kivugutomilk was processed in a 20 liters bioreactor with three bacteria previously selected in kivuguto traditional milk. The work aimed to study the association of three bacteria previously selected ... [more ▼]

The kivugutomilk was processed in a 20 liters bioreactor with three bacteria previously selected in kivuguto traditional milk. The work aimed to study the association of three bacteria previously selected in traditional kivuguto in order to reproduce it in a controlled fermentation, and thereafter to understand its stability during storage under refrigeration. Postacidification, viability, proteolysis, flavor compounds as well as rheological characteristics were monitored for 36 days. The ph decreases from 4.54 to 4.45 and the titratable acidity grew from 73°d to 79°d. The final biomass after storage was 0.60 108 cfu.g-1 which is far higher than the recommended 106 cells.g-1before consumption. The proteolysis was at a range of 3.0 to 7.0 mg.l-1of lysine equivalent, which is too low so that it can’t produce bitter peptides. The evolution of flavor compounds in storage showed that no change found with 3-methylbutan-1-ol, acetic acid and furan-2(5h)-one, whilst pentan-1-ol and furanmethan-2-ol increased slightly upon 24 days’ storage. The complex viscosity decreased from 4 - 5.3 pas before storage to 2.9 - 4.0 pas corresponding respectively to the ratio g''/g' of about 0.3-0.4 with a very low variation. These data allowed the production and the good preservation of kivuguto milk at 4°c on 36 days. [less ▲]

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See detail"Lire le rythme". Henri Meschonnics Theorie und Praxis des Lesens
Viehöver, Vera ULg

in Intervalles (2015), 7(2015), 41-60

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See detailThe Ras/Rap GTPase activating protein RASA3 : from gene structure to in vivo functions
Schurmans, Stéphane ULg; Polizzi, Séléna; Scoumanne, Ariane ULg et al

in Advances in Biological Regulation (2015), 57

RASA3 (or GTPase Activating Protein III, R-Ras GTPase-activating protein, GAP1IP4BP) is a GTPase activating protein of the GAP1 subfamily which targets Ras and Rap1. RASA3 was originally purified from pig ... [more ▼]

RASA3 (or GTPase Activating Protein III, R-Ras GTPase-activating protein, GAP1IP4BP) is a GTPase activating protein of the GAP1 subfamily which targets Ras and Rap1. RASA3 was originally purified from pig platelet membranes through its intrinsic ability to bind inositol 1,3,4,5-tetrakisphosphate (I(1,3,4,5)P4) with high affinity, hence its first name GAP1IP4BP (for GAP1 subfamily member which binds I(1,3,4,5)P4). RASA3 was thus the first I(1,3,4,5)P4 receptor identified and cloned. The in vitro and in vivo functions of RASA3 remained somewhat elusive for a long time. However, recently, using genetically-modified mice and cells derived from these mice, the function of RASA3 during megakaryopoiesis, megakaryocyte adhesion and migration as well as integrin signaling has been reported. The goal of this review is thus to summarize and comment recent and less recent data in the literature on RASA3, in particular on the in vivo function of this specific GAP1 subfamily member. [less ▲]

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See detailInstitutional Investors, adverse selection and stock market liquidity in France
Sougné, Danielle ULg; Aymen, Ajina; Faten, Lakhal

in International Journal of Managerial Finance (2015), 11

The purpose of this paper is to examine the effect of institutional investor's ownership and type on information asymmetry and stock market liquidity in France.The findings show that the proportion of ... [more ▼]

The purpose of this paper is to examine the effect of institutional investor's ownership and type on information asymmetry and stock market liquidity in France.The findings show that the proportion of institutional investors has a positive and significant effect on stock-market liquidity, which confirms the signal theory and trading hypothesis. These investors perform high trading activity which favorably affects market liquidity. The results also show that pension funds improve liquidity. This result suggests that pension funds manage huge assets decreasing transactions costs and improving liquidity. They display a positive signal to the market about more transparency and a low level of information asymmetry. [less ▲]

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See detailPrivate Versus Official? New Hypotheses for the Reconstruction of Bronze Age Upper Mesopotamian Economic System
Mas, Juliette ULg

Conference (2015, January)

Ancient economic systems from Southern and Central Mesopotamia are quite well known when Northern Mesopotamia ones remain less known. If we already know that, during Bronze Age, households played a ... [more ▼]

Ancient economic systems from Southern and Central Mesopotamia are quite well known when Northern Mesopotamia ones remain less known. If we already know that, during Bronze Age, households played a deciding role in several kinds of production, their degree of dependence or independence to the State still has to be clarified . The archaeological data clearly show that private workshops, set up in private houses, could be very efficient and specialized. Furthermore, these economic entities could be assimilated to private enterprises, which were able to handle their own administrative duties. On the other hand, we know from the texts that the Palace and the temples were also a main element of ancient economic systems. If public administrations should, in some cases, have supplied raw materials, hired workforce, and dealt with the distribution of produced goods, it seems that the production didn’t take place in the palace itself. Dealing both with archaeological and textual data could help to better define the role and the importance of both public and private components in early Mesopotamian economic systems. [less ▲]

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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 detailEpidemiological Review of Injuries in Rugby Union
Kaux, Jean-François ULg; Julia, Marc; Delvaux, François ULg et al

in Sports (2015), 3(1), 21-29

Rugby is a sport that is growing in popularity. A contact sport par excellence, it causes a significant number of injuries. In Rugby Union, there are 30 to 91 injuries per 1000 match hours. This ... [more ▼]

Rugby is a sport that is growing in popularity. A contact sport par excellence, it causes a significant number of injuries. In Rugby Union, there are 30 to 91 injuries per 1000 match hours. This epidemiological review of injuries incurred by rugby players mentions the position and type of injuries, the causes, time during the match and season in which they occur and the players’ positions as well as the length of players’ absences following the injury. [less ▲]

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See detailN1-Fluoroalkyltryptophan analogues: synthesis and in vitro study as potential substrates for indoleamine 2,3-dioxygenase
Henrottin, Jean ULg; Zervosen, Astrid ULg; Lemaire, Christian ULg et al

in ACS Medicinal Chemistry Letters (2015)

ABSTRACT: Indoleamine 2,3-dioxygenase (hIDO) is an enzyme that catalyzes the oxidative cleavage of the indole ring of L-tryptophan through the kynurenine pathway, thereby exerting immunosuppressive ... [more ▼]

ABSTRACT: Indoleamine 2,3-dioxygenase (hIDO) is an enzyme that catalyzes the oxidative cleavage of the indole ring of L-tryptophan through the kynurenine pathway, thereby exerting immunosuppressive properties in inflammatory and tumoral tissues. The syntheses of 1-(2-fluoroethyl)-tryptophan (1-FETrp) and 1-((1-(2-fluoroethyl)-1H-1,2,3-triazol-4-yl)methyl)-tryptophan, two N1-fluoroalkylated tryptophan derivatives, are described here. In vitro enzymatic assays with these two new potential substrates of hIDO show that 1-FETrp is a good and specific substrate of hIDO. Therefore, its radioactive isotopomer, 1-[18F]FETrp, should be a molecule of choice to visualize tumoral and inflammatory tissues and/or to validate new potential inhibitors. [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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