References of "2011"
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See detailHerschel discovery of a new class of cold, faint debris discs
Eiroa, C.; Marshall, J. P.; Mora, A. et al

in Astronomy and Astrophysics (2011), 536

We present Herschel PACS 100 and 160 μm observations of the solar-type stars α Men, HD 88230 and HD 210277, which form part of the FGK stars sample of the Herschel open time key programme (OTKP) DUNES ... [more ▼]

We present Herschel PACS 100 and 160 μm observations of the solar-type stars α Men, HD 88230 and HD 210277, which form part of the FGK stars sample of the Herschel open time key programme (OTKP) DUNES (DUst around NEarby Stars). Our observations show small infrared excesses at 160 μm for all three stars. HD 210277 also shows a small excess at 100 μm, while the 100 μm fluxes of α Men and HD 88230 agree with the stellar photospheric predictions. We attribute these infrared excesses to a new class of cold, faint debris discs. Both α Men and HD 88230 are spatially resolved in the PACS 160 μm images, while HD 210277 is point-like at that wavelength. The projected linear sizes of the extended emission lie in the range from ~115 to ≤ 250 AU. The estimated black body temperatures from the 100 and 160 μm fluxes are ≲22 K, and the fractional luminosity of the cold dust is L[SUB]dust[/SUB]/L[SUB] ⋆ [/SUB] ~ 10[SUP]-6[/SUP], close to the luminosity of the solar-system's Kuiper belt. These debris discs are the coldest and faintest discs discovered so far around mature stars, so they cannot be explained easily invoking "classical" debris disc models. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. [less ▲]

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See detailChronique bibliographique - Supplément 2000-2004
Veymiers, Richard ULg; Bricault, Laurent; Budischovsky, Marie-Christine et al

in Veymiers, Richard; Bricault, Laurent (Eds.) Bibliotheca Isiaca II (2011)

Chronique bibliographique qui, sur le modèle de "l’Inventaire Bibliographique des Isiaca" (IBIS), publié dans les "ÉPRO" entre 1972 et 1991, recense, avec un commentaire critique, les publications ... [more ▼]

Chronique bibliographique qui, sur le modèle de "l’Inventaire Bibliographique des Isiaca" (IBIS), publié dans les "ÉPRO" entre 1972 et 1991, recense, avec un commentaire critique, les publications touchant aux cultes isiaques entre 2000 et 2004. [less ▲]

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See detailValorisation de la Carte Numérique des Sols de Wallonie et d’une base de données disponible en analyse de sols, dans le cadre de l’évaluation du risque de pollution des eaux souterraines par les pesticides
Bah, Boubacar Billo ULg; Vanclooster, Marnik; Oger, Robert ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2011), 15(S2), 709-726

This study shows how the Digital Soil Map of Wallonia and the associated soil database Aardewerk can be combined with the MetaPEARL model to assess the sensitivity of agricultural soils to pesticide ... [more ▼]

This study shows how the Digital Soil Map of Wallonia and the associated soil database Aardewerk can be combined with the MetaPEARL model to assess the sensitivity of agricultural soils to pesticide transfer into underground water tables in Wallonia (Southern Belgium). MetaPEARL is based on an analytical expression which describes the concentration of leached pesticides at the soil profile bottom depending on available data on soil characteristics, climate and pesticide properties. The results show an important soil sensitivity to pesticide transfer with a coefficient of retention on organic matter (Kom) very weak (about 10 dm3.kg-1) or with a relatively high half-life time (DT50 about 60 days). In this case, the pesticide is weakly retained by soil organic matter or slowly degraded and then stays available in the soil and can be quickly leached during rainfalls. In other respects, the pesticide sensitivity to leaching is strongly correlated with soil texture and its organic matter content. It is also observed that the concentration of leached pesticide is strongly depending of the rainfall surplus (water flux into the soil or hydrous balance). A sensitivity analysis has shown that the model is very sensitive to soil thickness, to organic matter content, to the bulk density of the mineral fraction by textural classes and of the organic matter. Therefore, these pedological variables have to be assessed with the highest precision to avoid adding further uncertainty to the predictions obtained. On the basis of the most sensitive soil variables, the analysis of “spatial” uncertainty related to the results delivered by MetaPEARL, due to the consideration of an unique representative value by soil type and by region (deterministic approach), shows that this approach tends to under-estimate the concentration of pesticide leached in the soil. And that compared to the use of a stochastic simulation (probabilistic approach) which takes into account the soil characteristic variability within a given soil type. This stochastic approach allows also the calculation of a more relevant threshold of risk probability (percentile) which can be compared to an imposed standard in view to enhance a sustainable management of natural resources. [less ▲]

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See detailFormation initiale des enseignants à l'éveil scientifique: comment en faire une occasion d'apprentissage pour tous?
Beckers, Jacqueline ULg; Simons, Germain; Crahay, Marcel ULg et al

in Beckers, Jacqueline; Crahay, Marcel (Eds.) Approche par compétences et réduction des inégalités d'apprentissage entre élèves : de l'analyse des situations scolaires à la formation de enseignants (2011)

L'approche par compétences en sciences prônée par le décret nécessite de travailler la démarche scientifique en classe de façon complète : poser une question, formuler une hypothèse, chercher des ... [more ▼]

L'approche par compétences en sciences prônée par le décret nécessite de travailler la démarche scientifique en classe de façon complète : poser une question, formuler une hypothèse, chercher des résultats, expérimentaux ou non, exploiter ces résultats et conclure provisoirement. Cette façon de travailler est complexe et la façon dont l'enseignant va mettre en oeuvre les choses peut engendrer ou non des inégalités d'un élève à l'autre. Cet article est le récit d'une formation initiale d'enseignants du primaire. [less ▲]

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See detailLes cultes isiaques à Argos. Du mythe à l'archéologie
Veymiers, Richard ULg

in Veymiers, Richard; Bricault, Laurent (Eds.) Bibliotheca Isiaca II (2011, December)

Mis en rapport avec l’Égypte par leur passé légendaire, les Argiens semblent avoir accueilli Isis et les membres de son cercle dès la haute époque hellénistique. Ces cultes, pratiqués à l’origine en privé ... [more ▼]

Mis en rapport avec l’Égypte par leur passé légendaire, les Argiens semblent avoir accueilli Isis et les membres de son cercle dès la haute époque hellénistique. Ces cultes, pratiqués à l’origine en privé, ont rapidement gagné en popularité, peut-être sous l’influence des Ptolémées, pour finalement jouir d’une reconnaissance officielle dans la cité. Aucun site du Péloponnèse n’a livré autant de documents témoignant de l’implantation de ces divinités sur une aussi longue période, du IIIe siècle av. J.-C. au IIIe siècle apr. J.-C., sinon plus tard. Malgré tous ces "isiaca", les lieux de culte isiaques n’ont pas encore été clairement définis. Pausanias ne signale aucun sanctuaire dévolu à ces divinités. Plusieurs contextes archéologiques ont été associés à ces cultes, mais, le plus souvent, les identifications proposées demeurent difficiles à étayer. La zone la plus prometteuse, à peine explorée, reste, selon nous, le flanc oriental de la Larissa, dans les alentours du nymphée hadrianique, là où l’on a mis au jour deux dédicaces isiaques, ainsi qu’un petit Harpocrate de marbre. Bien évidemment, seules de nouvelles fouilles seraient susceptibles d’y assurer la présence d’un sanctuaire. [less ▲]

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See detailLarge-Scale Fire Test of Unprotected Cellular Beam Acting in Membrane Action
Vassart, Olivier; Bailey, C. G.; Hawes, M. et al

in Journal of Structural Fire Engineering (2011), 2(4), 259-268

This paper describes a full scale fire test performed the 27th of February 2010 on a composite floor for analysing the possibility of tensile membrane action to develop when the unprotected steel beams in ... [more ▼]

This paper describes a full scale fire test performed the 27th of February 2010 on a composite floor for analysing the possibility of tensile membrane action to develop when the unprotected steel beams in the central part of the floor are made of cellular beams. The natural fire was created by a wood crib fire load of 700 MJ/m2 and the 9 × 15 m floor survived the fire that peaked at 1000°C and lasted for 90 minutes. Blind predictions of the air temperature development by the software OZone and of the structural behaviour by the software SAFIR which proved quite satisfactory are also described. [less ▲]

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See detailThermo-reversible reactions for the preparation of smart materials: recyclable covalently-crosslinked shape memory polymers
Defize, Thomas ULg; Riva, Raphaël ULg; Thomassin, Jean-Michel ULg et al

in Macromolecular Symposia (2011), 309/310(1), 154-161

[4+2] thermoreversible Diels-Alder cycloaddition has been used to crosslink star-shaped poly(ε-caprolactone) in order to produce networks based on strong carbon-carbon covalent bondings. Depending on the ... [more ▼]

[4+2] thermoreversible Diels-Alder cycloaddition has been used to crosslink star-shaped poly(ε-caprolactone) in order to produce networks based on strong carbon-carbon covalent bondings. Depending on the nature of the Diels-Alder reactants, these bonds can be thermoreversibly broken, allowing re-processing of the polymer matrix. [less ▲]

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See detailRelaxation schemes for min max generalization in deterministic batch mode reinforcement learning
Fonteneau, Raphaël ULg; Ernst, Damien ULg; Boigelot, Bernard ULg et al

in 4th International NIPS Workshop on Optimization for Machine Learning (OPT 2011) (2011, December)

We study the min max optimization problem introduced in [Fonteneau, 2011] for computing policies for batch mode reinforcement learning in a deterministic setting. This problem is NP-hard. We focus on the ... [more ▼]

We study the min max optimization problem introduced in [Fonteneau, 2011] for computing policies for batch mode reinforcement learning in a deterministic setting. This problem is NP-hard. We focus on the two-stage case for which we provide two relaxation schemes. The first relaxation scheme works by dropping some constraints in order to obtain a problem that is solvable in polynomial time. The second relaxation scheme, based on a Lagrangian relaxation where all constraints are dualized, leads to a conic quadratic programming problem. Both relaxation schemes are shown to provide better results than those given in [Fonteneau, 2011]. [less ▲]

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See detailToxicokinetics of selenium in Chelonians: trophic exposure in Trachemys scripta scripta
Dyc, Christelle ULg; Greco, Anaïs; Das, Krishna ULg

(2011, December)

Background. Se is primordial for all development stages in oviparous species but can induce cellular damages (e.g. oxidative stress, histopathotoxicity) , embryo- and immunotoxicity (Usdi 1998; Hoffman ... [more ▼]

Background. Se is primordial for all development stages in oviparous species but can induce cellular damages (e.g. oxidative stress, histopathotoxicity) , embryo- and immunotoxicity (Usdi 1998; Hoffman 2002) , even at low concentration. Unlike birds and fishes, little is currently known on Se toxicology in reptiles, such as turtles. Most studies reported tissue burdens from field-captured or death animals but rarely provided an understanding of the dose, duration or pathway of exposure. Our present study aims to investigate toxicokinetic of Se through an in vivo and per os exposure of the yellow-bellied slider turtle Trachemys scripta scripta. Furthermore relationship between Se concentration in internal tissues (liver, kidney, muscle ) and external tissues (carapace, skin, blood) will evaluate usefulness of these last in the framework of non-invasive sampling in protected turtle species. Methodology. 160 yellow-bellied slider turtles, around four weeks old, were acquired in September 2010 and placed by pair in individual tank for a six-month acclimatization period. Lengths, as straight carapace length SCL, ranged from 1.7 to 6.4 cm. Three groups of 42 individuals each were designed. The feeding trial consisted in an eight-week supplementation period followed by a four-week depuration period. At some intervals during that time scale, six individuals per group were sacrificed and tissues were collected (carapace, scutes, skin, blood, liver, kidney, muscle) for selenium analysis. During the supplementation period, turtles were fed with diet containing 0 (control) , 23 or 47 µg.g-1 of selenium as seleno-L-methionine. During the depuration period, the remaining individuals were fed with non-supplemented control diet. Total selenium was investigated by ICPMS. Results and discussion. The Se-concentration in all collected tissues increased in a dose-dependent way over the course of the supplementation period. Se accumulation had no effect on survival, diet behavior or growth. Higher Se levels were observed in kidney, followed by muscle and blood. During the recovery period, Se levels decreased in tissues in a significantway except in blood, muscle and carapace. Blood, skin and carapace Se levels were positively correlated to those in kidney and muscle. Such relationships were also observed between liver and carapace, and blood. Results suggested a Se transfer through the food intake and the potential use of carapace and skin as relevant tools in non-invasive biomonitoring studies. [less ▲]

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See detailQuantile regression in nonparametric location-scale models with censored data
Heuchenne, Cédric ULg; Van Keilegom, Ingrid

Conference (2011, December)

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See detailL'identité wallonne aujourd'hui
Jacquemain, Marc ULg

in Germain, P.; Robaye, R. (Eds.) L'Etat de la Wallonie. Portrait d'un pays et de ses habitants (2011)

L'article fait le point sur le sentiment d'appartenance à la Wallonie et comment il a évolué au sein de la population au sein des quinze dernières années. Il remet en évidence la complémentarité naturelle ... [more ▼]

L'article fait le point sur le sentiment d'appartenance à la Wallonie et comment il a évolué au sein de la population au sein des quinze dernières années. Il remet en évidence la complémentarité naturelle entre le sentiment belge et le sentiment wallon. Il montre que le sentiment d'appartenance est évolutif, qu'il dépend non seulement de l'actualité mais des stratégies d'acteurs politique, économiques ou médiatiques. Il fait aussi l'hypothèse que l'identité wallonne, en terme de contenus, se définit davantage par un modèle socio-économique partagé que par des symboles et qu'elle ne présente donc pas de caractère d'identité nationale. [less ▲]

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See detailFibrosis and pulmonary function tests - New therapeutic options for respiratory diseases.
Clercx, Cécile ULg

in Proceedings of the Meeting of German specialists in internal medicine (ECVIM-CA-Internal Medicine) - Viernheim - 3rd December 2011 (2011, December)

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See detailDe la raclée à la tétée: la théorie de l'attachement, un modèle pour penser la prise en charge des familles maltraitantes.
Bullens, Quentin ULg

in Psychiatrie et Violence (2011)

From reading the Guedeney & Guedeney's book L'Attachement (2006) has become an issue: the use of attachment theory in a meta-analyse on the institutional caring of abusive families. This article explores ... [more ▼]

From reading the Guedeney & Guedeney's book L'Attachement (2006) has become an issue: the use of attachment theory in a meta-analyse on the institutional caring of abusive families. This article explores some possible parallels in the idea of helping to thinking about the treatment when sometimes violence impede it. [less ▲]

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See detailConstrained sparse estimation for improved fault isolation
Borguet, Sébastien ULg; Léonard, Olivier ULg

in Journal of Engineering for Gas Turbines & Power (2011), 133(12), 121602

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See detailEvaluation of organic dust components cytotoxicity on thp1 monocytes-derived-macrophages using high content analysis
Ramery, Eve ULg; O'Brien, Peter James

in Veterinary Clinical Pathology (2011, December), 40(4), 583

Background: Organic dust contains pathogen associated molecular patterns (PAMPs) which can induce, following chronic exposure, significant airway diseases. Mononuclear phagocytes are key protecting cells ... [more ▼]

Background: Organic dust contains pathogen associated molecular patterns (PAMPs) which can induce, following chronic exposure, significant airway diseases. Mononuclear phagocytes are key protecting cells of the respiratory tract. Several studies have investigated the effects of PAMPs, and mainly endotoxins, on cytokine production. However the sub-lethal cytotoxicity of organic dust components on macrophages has not been tested yet. The novel technology of high content analysis (HCA) is already used to assess subclinical drug-induced toxicity. It combines the capabilities of flow cytometry, intracellular fluorescence probes, and image analysis and enables to perform rapid multiple analysis in large numbers of samples. Objectives: The purpose of the present study was, by using HCA, to investigate the cytotoxicity of the 3 major PAMPs contained in organic dust, ie. endotoxin (LPS), peptidoglycan (PGN) and β-glucans (zymosan) on THP-1 monocyte-derived macrophages. Methods: LPS was used at concentrations of 0.005, 0.01, 0.02, 0.05, 0.1 and 1 μg/ml; PGN and zymosan were used at concentrations of 1, 5, 10, 50, 100 and 500 μg/ml. Cells were exposed to PAMPs for 24 hours. In addition, the oxidative burst and the phagocytic capabilities of the cells were tested. Results: An overlap between PGN intrinsic fluorescence and red/far-red fluorescent dyes occurred, rendering the evaluation of some parameters impossible for PGN. LPS induced sub-lethal cytotoxicity at the lowest dose (from 10 ng/ml). However, the most spectacular changes occurred with zymosan. In addition, zymosan, but not LPS, induced phagosome maturation and oxidative burst. Conclusions: Given the fact that β-glucans can be up to 100 fold more concentrated in organic dust than LPS, these results suggest that β-glucans could play a major role in macrophages impairment following heavy dust exposure and will deserve further investigation in the near future. [less ▲]

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See detailChronique bibliographique - 2005-2008
Veymiers, Richard ULg; Bricault, Laurent; Budischovsky, Marie-Christine et al

in Bricault, Laurent; Veymiers, Richard (Eds.) Bibliotheca Isiaca II (2011)

Chronique bibliographique qui, sur le modèle de "l’Inventaire Bibliographique des Isiaca" (IBIS), publié dans les "ÉPRO" entre 1972 et 1991, recense, avec un commentaire critique, les publications ... [more ▼]

Chronique bibliographique qui, sur le modèle de "l’Inventaire Bibliographique des Isiaca" (IBIS), publié dans les "ÉPRO" entre 1972 et 1991, recense, avec un commentaire critique, les publications touchant aux cultes isiaques entre 2005 et 2008. [less ▲]

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See detailLa sémiotique, entre autres / Semiotics, among others
Dondero, Maria Giulia ULg; Provenzano, François ULg; Klinkenberg, Jean-Marie ULg et al

in Signata. Annales des Sémiotiques = Annals of Semiotics (2011), 2

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See detailLes cultes isiaques en Grèce. Introduction. Actes du IVe colloque international sur les études isiaques, Troisième journée, Université de Liège, 29 novembre 2008, Michel Malaise in honorem
Veymiers, Richard ULg; Bricault, Laurent

in Veymiers, Richard; Bricault, Laurent (Eds.) Bibliotheca Isiaca II (2011)

Introduction thématique à la publication des Actes de la troisième journée du IVe colloque international sur les études isiaques, Université de Liège, 29 novembre 2011, Michel Malaise in honorem.

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See detailNovel amphiphilic mikto-arm star-shaped copolymers for the preparation of PLA-based nanocarriers
Cajot, Sébastien ULg; Riva, Raphaël ULg; Billiet, Leen et al

in Macromolecular Symposia (2011), 309/310(1), 111-122

Three-arm (A2B) and four-arm (A2B2) star-shaped copolymers based on biocompatible and biodegradable hydrophobic poly(ε-caprolactone) (PCL) (A arms) and biocompatible and bioeliminable hydrophilic poly ... [more ▼]

Three-arm (A2B) and four-arm (A2B2) star-shaped copolymers based on biocompatible and biodegradable hydrophobic poly(ε-caprolactone) (PCL) (A arms) and biocompatible and bioeliminable hydrophilic poly(ethylene oxide) (PEO) (B arms) were synthesized by the coupling of an ω-azide terminated PEO chains with PCL chain bearing one (A2B) or two (A2B2) alkyne functions at the middle of the chain by the copper mediated azide-alkyne cycloaddition (CuAAC). The amphiphilic behavior of these different stars was confirmed by micellization experiments in water followed by dynamic light scattering and transmission electron microscopy analyses. The efficiency to stabilize PLA nanoparticles was investigated in function of the stars structure. [less ▲]

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