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See detailNo efficiency of the lateral system on nocturnal feeding in the European sea bass (Dicentrarchus labrax L.)
Faucher, Karine ULg; Dutto, Gilbert; Covès, Denis et al

in Aquaculture (2006), 252(2-4), 462-475

In order to evaluate the effect and consequence of lateral system inactivation on fish nocturnal feeding, the differential growth of groups of European sea bass maintained in different rearing conditions ... [more ▼]

In order to evaluate the effect and consequence of lateral system inactivation on fish nocturnal feeding, the differential growth of groups of European sea bass maintained in different rearing conditions were compared. Whereas some fish with intact lateral system (placebo fish) were placed under a photoperiod of 12-L: 12-D, other placebo fish were kept in the dark. In the same way, fish deprived of lateral system by section of their lateral system nerves and antibiotic treatment were placed under a photoperiod of 12-L :12-D and the others in the dark. For each of these four rearing conditions, two sets of experiment were realized. Percent mortality, feed rhythm, averaged daily feed demand, specific growth rate and feed efficiency were compared among these four groups of fish. After four months of experiment, results revealed that, under a photoperiod of 12-L: 12-D, fish showed a diurnal feed rhythm whereas no rhythm appeared in fish kept in the dark. In addition, as reported by other authors, the average daily feed demand, the quantity of ingested food and specific growth rate were greater in fish maintained under a photoperiod of 12-L :12-D than those kept in the dark. The fish lateral system inactivation did not affect mortality, feed intake, specific growth rate or feed efficiency. These results demonstrated that lateral system is not the major sensory organ leading to European sea bass nocturnal feeding; chemoreception system undoubtedly taking over. If the olfactory system explains equal feed intake between placebo and treated fish, the greater specific growth rate in treated than in placebo fish indicates the action of another mechanism, such as a "booster effect" of antibiotics used for lateral system inactivation on fish. [less ▲]

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See detailL'accompagnement : une fonction multiforme, un contrat clair à établir d'emblée
Poumay, Marianne ULg

Learning material (2006)

La fonction d'accompagnateur est aujourd'hui répandue à travers de nombreux secteurs professionnels. Le présent document se propose de mobiliser deux auteures, Pierrette Massé et Maëlla Paul, pour dégager ... [more ▼]

La fonction d'accompagnateur est aujourd'hui répandue à travers de nombreux secteurs professionnels. Le présent document se propose de mobiliser deux auteures, Pierrette Massé et Maëlla Paul, pour dégager les caractéristiques essentielles de l'accompagnement et une taxonomie des postures d'accompagnement. Cette modélisation peut guider vers une classification empirique d'accompagnements réalisés dans le cadre de programmes tels "Formadis". [less ▲]

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See detailDu nouveau à l'interface materno-foetale: rôle du couple hCG/récepteur LH-hCG dans l'implantation embryonnaire
PERRIER d'HAUTERIVE, Sophie ULg; Charlet, Jeanne de Chantal ULg; Dubois, Michel ULg et al

in Revue Médicale de Liège (2006), 61(10), 705-12

Implantation of the embryo into the maternal endometrium represents a unique biological process, combining an immunological (tolerance of an allograft) and biological (adhesion of two epitheliums) paradox ... [more ▼]

Implantation of the embryo into the maternal endometrium represents a unique biological process, combining an immunological (tolerance of an allograft) and biological (adhesion of two epitheliums) paradox. The success of implantation depends on a receptive endometrium, a functionally normal blastocyst and a synchronized cross-talk between embryonic and maternal tissues. Though sexual steroids control the process, a cascade of growth factors or cytokines are the prime paracrine mediators of the dialogue at the maternal-embryonic interface. HCG is one of the molecules most precociously produced by the embryo and is the most specific marker of its presence. HCG is a luteotropic factor which relays the inadequate support provided by the reduced rates of LH, but also influences the pregnancy on a paracrine mode by a local action on implantation process, probably by interacting with its receptor, the LH/hCG-R that we have evidenced on endometrial epithelium. We demonstrate that embryo actively participate into its implantation, tolerance and placentation. [less ▲]

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See detailPeut-on gérer la forme urbaine ? Les enjeux de la régulation morphologique (France, Angleterre, Etats-Unis)
Teller, Jacques ULg

in Descat, S.; Siret, D. (Eds.) La ville durable au risque de l’histoire (2006)

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See detailThe APPEAR Method for guiding the valorisation of urban archaeological sites
Teller, Jacques ULg; Warnotte, A.; Tinant, M. et al

Scientific conference (2006)

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See detailSingle-player games: introduction to a new solving method
Van Lishout, François ULg

Master of advanced studies dissertation (2006)

In many games, the machine has become stronger than the best human players. Machines have already beaten the human World Champion in famous games like Checkers, Chess, Scrabble and Othello. However ... [more ▼]

In many games, the machine has become stronger than the best human players. Machines have already beaten the human World Champion in famous games like Checkers, Chess, Scrabble and Othello. However, mankind has not been humbled by chips in all games. The best human players are still stronger than computers in games like Go, Poker, Chinese Chess and Hex. In this thesis, we will focus on a new way to model single-player games in order to improve the performances of the machine. We will demonstrate this technique on the game of Sokoban. [less ▲]

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See detailRelevance of soil mapping criteria to predict geochemical background of trace elements in soils from local to regional scales.
Colinet, Gilles ULg; Bogaert, Patrick; Bock, Laurent ULg

Poster (2006)

Among natural factors driving the soil content in metallic trace elements (MTE), the geochemical background is often deemed as a sound base for the detection of contaminations. Numerous studies have shown ... [more ▼]

Among natural factors driving the soil content in metallic trace elements (MTE), the geochemical background is often deemed as a sound base for the detection of contaminations. Numerous studies have shown the difficulties to take into account the multi-dimensionnality of the spatial variability of most soil properties. As far as a detailed soil map is available for Belgium, the relevance of its information was investigated at various spatial scales in the Walloon Region (Southern Belgium), from the plot to the entire region, to evaluate the feasibility of a multi-scale mapping of geochemical background. A database of soil profiles (gathering both agricultural and forest soils) was used to analyse the relationships between the MTE total content (measured after HF-HClO4-HCl dissolution) and other general characteristics such as pH, Total Organic Carbon content (TOC), Particle Size Distribution (PSD), and cationic exchange capacity (CEC). The factors of MTE spatial distribution inside and between solums were investigated through multivariate statistical analysis. The spatial dependence of these factors was then studied over plot, field, farm, county and region scales, and compared to the spatial structures of the soil map parameters. At the solum level, strong relationships between most of the studied MTE were found, as well as between stone charge and fine earth contents. The PSD is the main driving factor of MTE content in non-carbonated soils, whatever the land use. When considering soil associations, such as catenas, the slope redistribution processes must be taken into account. However, the PSD remains the main driving factors and, as the soil map contains information about that property (mainly the textural class and the profile development), a cartography of the geochemical background based on the use of the soil map and pedotransfer functions or regression models appears relevant. At the regional scale, some long-range spatial structures could be identified. These result mainly from the geological structure of the Walloon region, where the lithological zonation is rather clearly marked. The soil map (texture and nature of stone charge) appears relevant at that scale too but does need a generalization process and fails however to differenciate the intra-type soil spatial variability. Some basic processes of integration of point measurements and qualitative information have been explored. They should be further investigated in the future. [less ▲]

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See detailMétaphysique phénoménologique, suite
Seron, Denis ULg

in Bulletin d'Analyse Phénoménologique (2006), 2(2), 3-75

This paper, which is the sequel of a previous essay published in the same collection, provides an overview of some basic problems related to the notion of a phenomenological metaphysics. The key thesis in ... [more ▼]

This paper, which is the sequel of a previous essay published in the same collection, provides an overview of some basic problems related to the notion of a phenomenological metaphysics. The key thesis in the paper is that the very starting point of all "critical" metaphysics should first consist in an intensional interpretation of existential propositions. Starting from the idea (for him distinctive of the phenomenological approach in general) that intensionality with an 's' now needs to be described in terms of the intentionality with a 't', the author tries to outline some implications and consequences of applying the methods used in phenomenology to metaphysical problems. He then briefly surveys some of the possible applications of this view, especially as to the theory of truth. [less ▲]

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See detailComparison of different non-linear equations and corresponding unitarization schemes
Selyugin, O. V.; Cudell, Jean-René ULg

in Proceedings of science (2006)

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See detailUse of artificial diet system to assess the potential bio-insecticide effect of a fungal lectin from Xerocomus chrysenteron (XCL) on Myzus persicae.
Jaber, K.; Paquereau, L.; Fournier, D. et al

in Communications in Agricultural and Applied Biological Sciences (2006), 71(2 Pt B), 497-505

Lectins are carbohydrate binding proteins which are widely distributed in nature: they have been isolated from microorganisms, fungi, plants and animals. Many of these proteins were tested for their ... [more ▼]

Lectins are carbohydrate binding proteins which are widely distributed in nature: they have been isolated from microorganisms, fungi, plants and animals. Many of these proteins were tested for their potential biocide effect on lot of pests. Indeed, lectins can cause dramatic changes in the cellular morphology and metabolism, particularly on the digestive system of insect having ingested them, by lectin binding to membrane glycosyl groups of the digestive tract cells. A fungal lectin, namely Xerocomus Chrysenteron lectin (XCL) was previously purified and was shown to be toxic to several pests including aphids. At the cell level, an increase in the endocytosis, the induction of morphological changes such as the actin cytoskeleton shape was determined. In this work, the recombinant XCL was produced and was tested for its potential aphicide effect on Myzus persicae, a polyphagous aphid found on more than 400 host plant species and transmitting more than 100 viral diseases. We developed bioassays using different artificial diets incorporating a broad range of XCL concentrations (from 10 microgx ml(-1) to lmg.ml(-1)) to assess the potential negative effects of XCL on the development and reproduction of the M. persicae aphid. Significant mortality rates, changes of developmental durations and nymph production were observed depending on the XCL concentration in the artificial diet. Concanavalin A lectin was also used in a new range of experiments to compare the effects of the two lectins on the aphid biological parameters. According to the observed dose responses toward the XCL and Con-A lectins included in the artificial diet and the action mode of this kind of proteins, the perspectives of lectin use in pest control will be discussed. [less ▲]

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See detailCorrosion behaviour of different hot rolled steels
Perez, F. J.; Martinez, L.; Hierro, M. P. et al

in Corrosion Science (2006), 48(2), 472-480

The oxidation-corrosion behaviour of hot rolled alloys was examined by electrochemical impedance spectroscopy. The corrosion behaviour of the non-oxidised alloys was first determined in order to have a ... [more ▼]

The oxidation-corrosion behaviour of hot rolled alloys was examined by electrochemical impedance spectroscopy. The corrosion behaviour of the non-oxidised alloys was first determined in order to have a reference behaviour. Then, each alloy was oxidised for 1 and 3 days at 650 degrees C in air and its corrosion behaviour was also determined. For all the alloys, Fe2O3 was formed at the scale-gas interface. However, the Fe2O3 crystallographic structures varied as a function of the alloy composition. Differences in the corrosion behaviour are due to the thickness, the microstructure and the porosity of the scale. The new graphite chromium iron alloy (Hi-Cr + C) have an oxidation-corrosion behaviour close to the indefinite chill double paired (ICDP) one and is therefore thought to be a good candidate to replace the ICPD alloy. In the case of the high speed steel (HSS) alloy, the oxidation-corrosion kinetics are too slow to prevent sticking problems. The Co addition decreases the corrosion-oxidation rates for the non-oxidised and oxidised samples but this effect is limited in time. (C) 2005 Elsevier Ltd. All rights reserved. [less ▲]

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See detailNew Role For Hpar-1 Kinases Emk And C-Tak1 In Regulating Localization And Activity Of Class Iia Histone Deacetylases
Dequiedt, Franck ULg; Martin, Maud ULg; Von Blume, Julia et al

in Molecular and Cellular Biology (2006), 26(19), 7086-102

Class IIa histone deacetylases (HDACs) are found both in the cytoplasm and in the nucleus where they repress genes involved in several major developmental programs. In response to specific signals, the ... [more ▼]

Class IIa histone deacetylases (HDACs) are found both in the cytoplasm and in the nucleus where they repress genes involved in several major developmental programs. In response to specific signals, the repressive activity of class IIa HDACs is neutralized through their phosphorylation on multiple N-terminal serine residues and 14-3-3-mediated nuclear exclusion. Here, we demonstrate that class IIa HDACs are subjected to signal-independent nuclear export that relies on their constitutive phosphorylation. We identify EMK and C-TAK1, two members of the microtubule affinity-regulating kinase (MARK)/Par-1 family, as regulators of this process. We further show that EMK and C-TAK1 phosphorylate class IIa HDACs on one of their multiple 14-3-3 binding sites and alter their subcellular localization and repressive function. Using HDAC7 as a paradigm, we extend these findings by demonstrating that signal-independent phosphorylation of the most N-terminal serine residue by the MARK/Par-1 kinases, i.e., Ser155, is a prerequisite for the phosphorylation of the nearby 14-3-3 site, Ser181. We propose that this multisite hierarchical phosphorylation by a variety of kinases allows for sophisticated regulation of class IIa HDACs function. [less ▲]

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See detailEffect of boundary conditions and heat source distribution on temperature distribution in friction stir welding
Simar, A.; Lecomte-Beckers, Jacqueline ULg; Pardoen, T. et al

in Science & Technology of Welding & Joining (2006), 11(2), 170-177

on Al-6005A have been carried out using a fully instrumented milling machine. The power input was calculated from the measured torque and forces. The thermal cycles were measured at various locations ... [more ▼]

on Al-6005A have been carried out using a fully instrumented milling machine. The power input was calculated from the measured torque and forces. The thermal cycles were measured at various locations close to the weld centreline. A finite element pseudothermal model was developed, taking into account the influence of the welding parameters on the power input. The distribution of the total power input between surface and volume heat sources was also studied. The measured and predicted thermal cycles are in good agreement when proper contact conditions between the workpiece and the backing plate are introduced. [less ▲]

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See detailSaturation effects in diffractive scattering at LHC energies
Selyugin, O. V.; Cudell, Jean-René ULg

in Kolganova, E.; Sissakian, A.; Kozlov, G. (Eds.) ICHEP 2006: Proceedings (2006)

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See detailLe risque sismique et sa prévention en Région Wallonne
Camelbeek, Thierry; Barszez, Anne-Marie; Plumier, André ULg

in Les risques majeurs en Région Wallonne (2006)

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See detailTwo INnovations for Earthquake Resistant Design: The INERD Project.
Plumier, André ULg; Doneux, Catherine; CASTIGLIONI, C. et al

Report (2006)

The project develops two innovations. The first innovation promotes a construction measure by which the "soft storey" mechanism is obviated in the lower storeys of reinforced concrete (R.C.) frames by ... [more ▼]

The project develops two innovations. The first innovation promotes a construction measure by which the "soft storey" mechanism is obviated in the lower storeys of reinforced concrete (R.C.) frames by encasing steel profiles in R.C. columns in order to provide them with a basic reliable shear, bending and compression resistance. Tests are performed and comparison of the behaviour of reference reinforced concrete and composite specimens made. Several parameters are studied: axial load, length of anchorage, stiffeners in the panel zone, weak and strong axis bending, configurations with and without infills. The study defines design rules for steel profiles to be encased in ductile R.C. columns, formulas for the behaviour of local strut and tie mechanism in presence of infills and formulas for the calculation of the shear resistance of a composite beam-to-column panel zone in configurations without infills. The second innovation consists in using dissipative connections for diagonals of frames with concentric bracings. Two types of connections are studied: the “pin” connections, made of bent rounded or rectangular bars, and “U-device” connection, made of plates bent in U. Their behaviour is studied experimentally on connections and on complete bracings. Design rules are defined, especially for the pin connection, and fatigue curves obtained. The applicability and interest are set forward by numerical studies and comparative design of structures with classical and with dissipative connections. The innovation demonstrates a higher capacity to dissipate energy. It can be translated into higher behaviour factor q. [less ▲]

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See detailETUDE DE L’ÉVOLUTION DE LA GERMINATION, DE LA CROISSANCE ET DE LA PHÉNOLOGIE DE FLORAISON CHEZ SENECIO INAEQUIDENS DC. (ASTERACEAE) LORS DE SON INVASION EN EUROPE.
Monty, Arnaud ULg

Master of advanced studies dissertation (2006)

Senecio inaequidens DC. (Asteraceae) est une plante invasive introduite involontairement par l’industrie lainière il y a environ un siècle. Introduite à plusieurs reprises dans des zones indépendantes et ... [more ▼]

Senecio inaequidens DC. (Asteraceae) est une plante invasive introduite involontairement par l’industrie lainière il y a environ un siècle. Introduite à plusieurs reprises dans des zones indépendantes et connues, elle est maintenant présente dans une grande partie de l’Europe de l’ouest, où seul des individus tétraploïdes sont observés. Des collectes de graines ont été menés le long de deux gradients altitudinaux et climatiques, en Belgique et dans le sud de la France (respectivement 8 et 10 populations). Dix individus parents par population ont été échantillonnés. Par ailleurs, des graines d’Afrique, venant de deux populations diploïdes et deux populations tétraploïdes, ont été reçues. Dix graines par individu parent ont été semées en pots dans un jardin expérimental en conditions homogènes, à Gembloux (Belgique), afin d’étudier les éventuelles différenciations entre continents et le long des gradients climatiques. Un pot par plant a été gardé. Les données collectées concernent la germination, la phénologie de floraison et la croissance. L’analyse ne permet pas de mettre en évidence de différences marquées entre les plants africains et européens d’une part, et entre cytotypes d’autre part. Par contre une relation entre la plupart des caractères étudiés et l’altitude a été montrée pour la zone française, reflétant une différenciation adaptative de l’espèce dans cette zone après l’invasion. Les résultats du transect belge sont nettement moins clairs, ce qui est à mettre en relation avec une moins grande différence d’altitude et des climats moins contrastés. [less ▲]

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See detailClinical data based optimal STI strategies for HIV: a reinforcement learning approach
Ernst, Damien ULg; Stan, Guy-Bart; Gonçalves, Jorge et al

in Proceedings of the 45th IEEE Conference on Decision and Control (CDC 2006) (2006)

This paper addresses the problem of computing optimal structured treatment interruption strategies for HIV infected patients. We show that reinforcement learning may be useful to extract such strategies ... [more ▼]

This paper addresses the problem of computing optimal structured treatment interruption strategies for HIV infected patients. We show that reinforcement learning may be useful to extract such strategies directly from clinical data, without the need of an accurate mathematical model of HIV infection dynamics. To support our claims, we report simulation results obtained by running a recently proposed batch-mode reinforcement learning algorithm, known as fitted Q iteration, on numerically generated data. [less ▲]

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See detailApplications of security-constrained optimal power flows
Capitanescu, Florin ULg; Glavic, Mevludin; Ernst, Damien ULg et al

in In Proceedings of Modern Electric Power Systems Symposium, MEPS06 (2006)

This paper proposes to formulate security control as a sequential decision making problem and presents new developments in automatic learning of sequential decision making strategies from simulations and ... [more ▼]

This paper proposes to formulate security control as a sequential decision making problem and presents new developments in automatic learning of sequential decision making strategies from simulations and/or information collected from real-life system measurements. The exploitation of these methods for the design of decision making strategies and control policies in the context of preventive and emergency mode dynamic security assessment and control is discussed and further opportunities for research in this area are highlighted. [less ▲]

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