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See detailLa fédération belge
Reuchamps, Min ULg; Onclin, François ULg

in Fournier, Bernard; Reuchamps, Min (Eds.) Le fédéralisme en Belgique et au Canada. Comparaison sociopolitique (2009)

The current Belgian federation is the product of a long and slow process of federalisation which started in the 1960’s but which find its multiple roots before that time and was mainly the result of the ... [more ▼]

The current Belgian federation is the product of a long and slow process of federalisation which started in the 1960’s but which find its multiple roots before that time and was mainly the result of the pressure of the Flemish movement. History can thus explain the originality – and the complexity – of the Belgian federal structure. This federal structure is made of a federal Authority, three Communities and three Regions. In this introductory chapter, we present the origins, the formation and the evolution of the Belgian federation. We then describe its structure, the institutions and the actors. [less ▲]

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See detailLa fédération canadienne
Fournier, Bernard ULg

in Fournier, Bernard; Reuchamps, Min (Eds.) Le fédéralisme en Belgique et au Canada : comparaison sociopolitique (2009)

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See detailLa Fédération des Banques de Données Biogéographiques (F.B.D.B.).
Dufrêne, Marc ULg

in I.F.B.L. Feuille de contact trimestrielle (1990), 8

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See detailLes fédérations d’entreprises et les règles de concurrence
Petit, Nicolas ULg

Conference (2009, March 13)

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See detailFederico García Lorca en Lieja
Francois, Jeromine ULg

E-print/Working paper (2014)

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See detailFederico García Lorcas Marionettentheater
Ceballos Viro, Alvaro ULg

in Das Andere Theater (2009), 73

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See detailThe Fedorivka layered intrusion (Korosten Pluton, Ukraine): An example of highly differentiated ferrobasaltic evolution
Duchesne, Jean-Clair ULg; Shumlyanskyy, L.; Charlier, Bernard ULg

in Lithos (2006), 89(3-4), 353-376

This study documents the petrography and whole-rock major and trace element geochemistry of 38 samples mainly from a drill core through the entire Fedorivka layered intrusion (Korosten Pluton), as well as ... [more ▼]

This study documents the petrography and whole-rock major and trace element geochemistry of 38 samples mainly from a drill core through the entire Fedorivka layered intrusion (Korosten Pluton), as well as mineral compositions (microprobe analyses and separated mineral fraction analyses of plagioclase, iltnenitc, magnetite and apatite) of 10 samples. The Fedorivka layered intrusion can be divided into 4 lithostratigraphic units: a Lower Zone (LZ, 72 to thick), a Main Zone (MZ, 160 m thick), and an Upper Border Zone, itself subdivided into 2 sub-zones (UBZ(2), 40 m thick; UBZ(1), 50 m thick). Igneous lamination defines the cumulate texture, but primary cumulus minerals have been affected by trapped liquid crystallization and subsolidus recrystallization. The dominant cumulus assemblage in MZ and UBZ(2) is andesine (An(39-42)), iron-rich olivine (Fo(32-42)), augite (En(29-35)Fs(24-29)Wo(42-44)), ilmenite (Hem(1-6)), Ti-magnetite (Usp(52-78)), and apatite. The data reveal a continuous evolution from the floor of the intrusion (LZ) to the top of MZ, due to fractional crystallization, and an inverse evolution in UBZ, resulting from crystallization downwards from the roof. The whole-rock Fe/Mg ratio and incompatible element contents (e.g. Rb, Nb, Zr, REE) increase in the fractionating magma, whereas compatible elements (e.g. V, Cr) steadily decrease. The intercumulus melt remained trapped in the UBZ cumulates due to rapid cooling and lack of compaction, and cumulus mineral compositions re-equilibrated (e.g. olivine, Fe-Ti oxides). In LZ, the intercumulus melt was able to partially or totally escape. The major element composition of the MZ cumulates can be approximated by a mixing (linear) relationship between a plagioclase pole and a mafic pole, the latter being made up of all mafic minerals in (nearly) constant relative proportions. By analogy with the ferrobasaltic/jotunitic liquid line of descent, defined in Rogaland, S. Norway, and its conjugated cumulates occurring in the Transition Zone of the Bjerkreim-Sokndal intrusion (Rogaland, a monzonitic (57% SiO2) melt is inferred to be in equilibrium with the MZ cumulates. The conjugated cumulate composition falls (within error) on the locus of cotectic compositions fixed by the 2-pole linear relationship. Ulvospinel is the only Ti phase in some magnetites that have been protected from oxidation. QUIlF equilibria in these samples show that magnetite and olivine in MZ have retained their liquidus compositions during subsolidus cooling. This permits calculation of liquidus fO(2) conditions, which vary during fractionation from Delta FMQ=0.7 to -1.4 log units. Low fO(2) values are also evidenced by the late appearance of cumulus magnetite (Fo(42)) and the high V3+-content of the melt, reflected in the high V-content of the first liquidus magnetite (up to 1.85% V). (C) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailFEED INGREDIENTS, PATHOGEN COLONIZATION AND GUT HEALTH IN PIGS
Van Kessel, Andrew; Pieper, Robert; Bindelle, Jérôme ULg et al

in Proceeding of the 47th Eastern Nutrition Conference (2011)

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See detailFeed restriction and IGFBP in bulls: effects of increasing starving period lengths.
Massart, Serge; Van Eenaeme, Christian ULg; Renaville, Robert ULg et al

in Journal of Animal Science (1995), 73(suppl 1), 225

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See detailFeed restriction in young bulls alters the onset of puberty in relationship with plasma insulin-like growth factor-I (IGF-I) and IGF-binding proteins
Portetelle, Daniel ULg; Massart, Serge; Van Eenaeme, Christian ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (1998), 2(special issue), 70

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See detailFeed restriction in young bulls alters the onset of puberty in relationship with plasma insulin-like growth factor-I (IGF-I) and IGF-binding proteins.
Renaville, Robert ULg; Van Eenaeme, Christian ULg; Breier, B. H. et al

in Domestic Animal Endocrinology (2000), 18(2), 165-76

The objectives of this study were to evaluate the effect of feed restriction and re-alimentation on the onset of puberty and IGF status in peripubertal male calves and to compare the radioimmunoassay (RIA ... [more ▼]

The objectives of this study were to evaluate the effect of feed restriction and re-alimentation on the onset of puberty and IGF status in peripubertal male calves and to compare the radioimmunoassay (RIA) and western ligand blotting (WLB) methods for bovine IGFBP-2. Twelve prepubertal 290 d-old Belgian Blue bulls (mean weight: +/- 290 kg) were randomly assigned in three groups: a control group (NG; n = 4) receiving a classic fattening diet to induce "normal" growth (1.48 kg/d), a feed restricted group (RG; n = 4) to obtain reduced growth (0.50 kg/d) and, a severely restricted group (SG; n = 4) to nearly stop growth (0.08 kg/d). The feed restriction period was maintained over a period of 114 d. After the period of differential feeding, all animals received the control feed regime over a period of 100 d. Blood samples were collected at fortnightly intervals. Circulating IGF-I was measured by RIA whereas plasma IGFBPs was evaluated by WLB; IGFBP-2 was additionally quantified by RIA procedure. At the beginning of the trial, IGF-I levels were low (<100 ng/ml) and similar in the three groups in accordance with prepubertal status. In the NG group, a progressive rise in IGF-I was observed from Day 42 to Day 142 whereas in the RG and SG groups, IGF-I levels did not change until the experimental restriction period ended. The delay of the rise in plasma IGF-I was longer for the SG group, IGF-I remained low until 2 wk after the end of the period of restricted feeding. Surprisingly, although differences were detected for IGF-I levels between the three groups, the IGFBP-2 and -3 data, evaluated by WLB could only discriminate between NG and SG group and not between NG and RG. However, by using a RIA method, an IGFBP-2 decrease was observed in the NG group coincident with increasing IGF-I levels. For both RG and SG groups, IGFBP-2 levels remained high throughout the feed restriction period whereas plasma IGFBP-2 levels declined upon feeding in both groups. During this feed restriction period, IGFBP-2 was significantly lower in NG than in RG or SG groups. Moreover, SG group animals had higher levels in plasma IGFBP-2 than RG animals. In conclusion, puberty is characterized by developmental changes in plasma IGF-I and IGFBPs that were altered by feed restriction. Moreover, RIA evaluation of plasma IGFBP-2 is able to better reflect group differences than WLB. [less ▲]

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See detailFeedback Control of Impact Dynamics: the Bouncing Ball Revisited
Ronsse, Renaud; Sepulchre, Rodolphe ULg

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

We study the the design of a tracking controller for the popular bouncing ball model: the continuous-time actuation of a table is used to control the impacts of the table with a bouncing ball. The ... [more ▼]

We study the the design of a tracking controller for the popular bouncing ball model: the continuous-time actuation of a table is used to control the impacts of the table with a bouncing ball. The proposed control law uses the impact times as the sole feedback information. We show that the acceleration of the table at impact plays no role in the stability analysis but is an important parameter for the robustness of the feedback system to model uncertainty, in particular to the uncertainty on the coefficient of restitution. [less ▲]

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See detailA feedback control perspective on models of apoptosis signal transduction
Readman, Mark C.; Schliemann, Monica; Kalamatianos, Dimitrios et al

in Chaos, Solitons & Fractals (2013)

Apoptosis is a key regulator for replacing unused, old and damaged cells. Here we analyse three models of apoptosis. We deconstruct these models by linearising the models about the life steady state and ... [more ▼]

Apoptosis is a key regulator for replacing unused, old and damaged cells. Here we analyse three models of apoptosis. We deconstruct these models by linearising the models about the life steady state and applying methods from linear control theory. This control viewpoint uncovers a decentralised control scheme with a clear separation of plant and controller and reveals that the caspase inhibitors act as decentralised phase lead controllers. © 2013 Elsevier Ltd. All rights reserved. [less ▲]

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See detailFeedback control strategies for spatial navigation revealed by dynamic modelling of learning in the Morris water maze
Fey, Dirk ULg; Commins, Sean; Bullinger, Eric ULg

in Journal of Computational Neuroscience (2011), 30(2), 447-454

The Morris water maze is an experimental procedure in which animals learn to escape swimming in a pool using environmental cues. Despite its success in neuroscience and psychology for studying spatial ... [more ▼]

The Morris water maze is an experimental procedure in which animals learn to escape swimming in a pool using environmental cues. Despite its success in neuroscience and psychology for studying spatial learning and memory, the exact mnemonic and navigational demands of the task are not well understood. Here, we provide a mathematical model of rat swimming dynamics on a behavioural level. The model consists of a random walk, a heading change and a feedback control component in which learning is reflected in parameter changes of the feedback mechanism. The simplicity of the model renders it accessible and useful for analysis of experiments in which swimming paths are recorded. Here, we used the model to analyse an experiment in which rats were trained to find the platform with either three or one extramaze cue. Results indicate that the 3-cues group employs stronger feedback relying only on the actual visual input, whereas the 1-cue group employs weaker feedback relying to some extent on memory. Because the model parameters are linked to neurological processes, identifying different parameter values suggests the activation of different neuronal pathways. [less ▲]

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See detailFeedback from reservoir sedimentation on the flow pattern in rectangular basins
Camnasio, Erica; Erpicum, Sébastien ULg; Orsi, Enrico et al

in 6th International Conference on Scour and Erosion (ICSE) (2012, August)

Despite simple geometries, flow in shallow rectangular reservoirs show complex recirculation patterns, which strongly influence the sediment deposits and, in practice, affect the operation and maintenance ... [more ▼]

Despite simple geometries, flow in shallow rectangular reservoirs show complex recirculation patterns, which strongly influence the sediment deposits and, in practice, affect the operation and maintenance costs of such facilities. Based on composite modelling, this research characterizes flow and sedimentation patterns in geometric conditions which have not been investigated so far. Velocity fields developing in rectangular shallow reservoirs (h = 0.2 m) with different asymmetric locations of the inlet and the outlet channels were experimentally investigated. Tests were performed in a reservoir geometry (4.5 m x 4 m) characterized by a stable symmetric flow pattern in the basic symmetric configuration, at constant hydraulic conditions; the aim was to evaluate exclusively the effect of channels displacing on the flow patterns and on the sedimentation of suspended solids. Horizontal velocity components were measured by ultrasound velocity profilers in the entire reservoir and maps of velocity vectors were obtained. Velocity measurements were performed both with clear water and with an inflowing suspended load. At the end of the experiments sediments deposits thickness on the entire reservoir bottom was measured by a laser light method, and maps of sediments deposits thickness were produced. Reservoir trapping efficiency was evaluated, but no significant influence of inlet and outlet channels location on trapping efficiency was observed. Numerical simulations were performed with the depth-averaged model WOLF 2D, in order to assess the ability of the model to reproduce the different types of flow patterns found in the experiments. In particular, a sensitivity analysis on bottom roughness as well as on the turbulence closure model and parameter was performed, in order to analyze a possible feedback effect of sediment deposits and/or suspended load on the type of flow pattern. [less ▲]

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See detailA feedback loop between the liver-enriched transcription factor network and mir-122 controls hepatocyte differentiation.
Laudadio, Ilaria; Manfroid, Isabelle ULg; Achouri, Younes et al

in Gastroenterology (2012), 142(1), 119-29

BACKGROUND & AIMS: Hepatocyte differentiation is controlled by liver-enriched transcription factors (LETFs). We investigated whether LETFs control microRNA expression during development and whether this ... [more ▼]

BACKGROUND & AIMS: Hepatocyte differentiation is controlled by liver-enriched transcription factors (LETFs). We investigated whether LETFs control microRNA expression during development and whether this control is required for hepatocyte differentiation. METHODS: Using in vivo DNA binding assays, we identified miR-122 as a direct target of the LETF hepatocyte nuclear factor (HNF) 6. The role and mechanisms of the HNF6-miR-122 gene cascade in hepatocyte differentiation were studied in vivo and in vitro by gain-of-function and loss-of-function experiments, using developing mice and zebrafish as model organisms. RESULTS: HNF6 and its paralog Onecut2 are strong transcriptional stimulators of miR-122 expression. Specific levels of miR-122 were required for proper progression of hepatocyte differentiation; miR-122 stimulated the expression of hepatocyte-specific genes and most LETFs, including HNF6. This indicates that HNF6 and miR-122 form a positive feedback loop. Stimulation of hepatocyte differentiation by miR-122 was lost in HNF6-null mice, revealing that a transcription factor can mediate microRNA function. All hepatocyte-specific genes whose expression was stimulated by miR-122 bound HNF6 in vivo, confirming their direct regulation by this factor. CONCLUSIONS: Hepatocyte differentiation is directed by a positive feedback loop that includes a transcription factor (HNF6) and a microRNA (miR-122) that are specifically expressed in liver. These findings could lead to methods to induce differentiation of hepatocytes in vitro and improve our understanding of liver cell dedifferentiation in pathologic conditions. [less ▲]

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See detailFeedback loops: From cellular to network principles
Dethier, Julie ULg

Scientific conference (2015, January 12)

Biological rhythms play a major role in the functioning of the brain. However, the generation mechanisms and functions of these rhythms are still under debate and the question of which cellular details ... [more ▼]

Biological rhythms play a major role in the functioning of the brain. However, the generation mechanisms and functions of these rhythms are still under debate and the question of which cellular details must be retained at the network level is largely open. In this presentation, I will highlight that cellular properties have a major impact at the network level, especially in the study of modulation and robustness. I will focus on a particular cellular property, a positive feedback loop in a specific timescale, and illustrate its network level impact with two simple examples: the modulation and robustness of an half-center oscillator, a very simple central pattern generator composed of two reciprocal-inhibitory populations, and the control of transient beta-band oscillations in the basal ganglia, a group of subcortical nuclei that act as a cohesive functional unit, in relation to motor movements. [less ▲]

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See detailFeedback mechanisms for global oscillations in Lure systems
Sepulchre, Rodolphe ULg; Stan, G. B.

in Systems & Control Letters (2005), 54(8), 809-818

The paper presents two mechanisms for global oscillations in feedback systems, based on bifurcations in absolutely stable systems. The external characterization of the oscillators provides the basis for a ... [more ▼]

The paper presents two mechanisms for global oscillations in feedback systems, based on bifurcations in absolutely stable systems. The external characterization of the oscillators provides the basis for a (energy-based) dissipativity theory for oscillators, thereby opening new possibilities for rigorous stability analysis of high-dimensional systems and interconnected oscillators. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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