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See detaillocalized modulation of testosterone action: Function of steroid receptor coactivators in the brain
Charlier, Thierry ULg; Balthazart, Jacques ULg

in Ardis, L. I. (Ed.) New research on testosterone (2008)

Testosterone, through its activation of androgen and estrogen receptors, has been shown to play a critical role in brain development and physiology. Recent studies have shown that the activity of these ... [more ▼]

Testosterone, through its activation of androgen and estrogen receptors, has been shown to play a critical role in brain development and physiology. Recent studies have shown that the activity of these receptors can be modulated by the interaction with several proteins and, in particular, that coactivators are required to enhance their transcriptional activity. The steroid receptor coactivator-1, SRC-1 is the best-characterized coactivator and we review here the current knowledge on the distribution, regulation of expression and function of this protein in the brain, focusing mostly on our work in Japanese quail. As expected for a ubiquitous coactivator, SRC-1 is present throughout the brain in both mammalian and avian species but is found in particularly high concentrations in testosterone-sensitive areas such as the preoptic area in rat and Japanese quail and in the song control nuclei in songbirds. Further analysis demonstrates that the expression of SRC-1 is not constitutive but regulated in specific brain areas by the sex, acute stress and testosterone treatment. In addition, the protein concentration appears to fluctuate through the day in some brain regions. These modulations of SRC-1 expression by endogenous (sex) and exogenous (stress) factors could potentially exacerbate at specific times the competition or squelching between different nuclear receptors and therefore decrease the biological response induced by one or another hormonal system. Although the existence of such a phenomenon has not yet been demonstrated in a functionally intact biological system, the effects of SRC-1 antisense treatments clearly strengthen this hypothesis. Indeed, the decrease of SRC-1 expression in the hypothalamus induced by antisense oligonucleotide injections clearly inhibited both estrogen-dependent male sexual behavior and androgen-dependent pre- and post-copulatory displays (strut) in Japanese quail, therefore demonstrating a role of the coactivator in the transcriptional activation induced by both estrogen and androgen receptors. Interestingly, the inhibitory effect on sexual behavior of SRC-1 knock down was not systematically associated with modifications of several histological (definition of median preoptic nucleus [POM] using Nissl staining), immunohistochemical (aromatase and vasotocin cells and fibers in the POM) and biochemical (aromatase enzymatic activity) markers of testosterone action in the brain. This dissociation of the effects of SRC-1 on behavior on the one hand and on aromatase and POM neurochemistry on another hand suggests that other system(s) involved in the activation of male sexual behavior are likely more sensitive to a decrease of SRC-1 expression. In future research, it will be essential to determine the other cofactors involved in specific physiological responses and to define whether these coactivators act synergistically, in parallel or independently in the modulation of the activity of one or several nuclear receptors linked to a particular physiological event. In several biological models, the observed changes in concentration of the circulating hormone and /or its receptors are apparently not sufficient to explain the physiological and behavioral responses observed after testosterone treatment. The discovery of steroid receptor coactivators opens new perspectives in the study of the molecular basis of steroid action at the level of the organism and a complete understanding of the mechanisms of steroid action will not be achieved without a detailed characterization of nuclear receptor cofactors. [less ▲]

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See detailLocalizing and comparing weight maps generated from linear kernel machine learning models
Schrouff, Jessica ULg; CREMERS, Julien ULg; GARRAUX, Gaëtan ULg et al

in 2013 Third International Workshop on Pattern Recognition in NeuroImaging (PRNI 2013): proceedings (2013)

Recently, machine learning models have been applied to neuroimaging data, allowing to make predictions about a variable of interest based on the pattern of activation or anatomy over a set of voxels ... [more ▼]

Recently, machine learning models have been applied to neuroimaging data, allowing to make predictions about a variable of interest based on the pattern of activation or anatomy over a set of voxels. These pattern recognition based methods present undeniable assets over classical (univariate) techniques, by providing predictions for unseen data, as well as the weights of each voxel in the model. However, the obtained weight map cannot be thresholded to perform regionally specific inference, leading to a difficult localization of the variable of interest. In this work, we provide local averages of the weights according to regions defined by anatomical or functional atlases (e.g. Brodmann atlas). These averages can then be ranked, thereby providing a sorted list of regions that can be (to a certain extent) compared with univariate results. Furthermore, we defined a “ranking distance”, allowing for the quantitative comparison between localized patterns. These concepts are illustrated with two datasets. [less ▲]

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See detailLOCALLY BOUNDED NONCONTINUOUS LINEAR-FORMS ON STRONG DUALS OF NONDISTINGUISHED KOTHE ECHELON SPACES
Bastin, Françoise ULg; Bonet, Jose

in Proceedings of the American Mathematical Society (1990), 108(3), 769-774

In this note it is proved that if Al (A) is any nondistinguished Kothe echelon space of order one and K. ,0 (AI (A))' is its strong dual, then there is even a linear form : K - C which is locally bounded ... [more ▼]

In this note it is proved that if Al (A) is any nondistinguished Kothe echelon space of order one and K. ,0 (AI (A))' is its strong dual, then there is even a linear form : K - C which is locally bounded (i.e. bounded on the bounded sets) but not continuous. It is also shown that every nondistinguished Kothe echelon space contains a sectional subspace with a particular structure [less ▲]

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See detailLocating carbon nanotubes (CNTs) at the surface of polymer microspheres using poly(vinyl alcohol) grafted CNTs as dispersion co-stabilizers
Thomassin, Jean-Michel ULg; Molenberg, Isabel; Huynen, Isabelle et al

in Chemical Communications (2010), 46(3330), 3332

In this communication, we prepared carbon nanotubes (CNTs) modified by poly(vinyl alcohol) that are used as co-stabilizers for the dispersion polymerization of methyl methacrylate. Poly(methyl ... [more ▼]

In this communication, we prepared carbon nanotubes (CNTs) modified by poly(vinyl alcohol) that are used as co-stabilizers for the dispersion polymerization of methyl methacrylate. Poly(methyl methacrylate) microspheres with CNTs selectively located at their surface are formed. This specific localization is a way to enhance the electrical conductivity of the nanocomposite. [less ▲]

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See detailLocating Migration: Rescaling Cities and Migrants
Martiniello, Marco ULg

in Glick Schiller, Nina; Çagglar, Ayse (Eds.) Locating Migration: Rescaling Cities and Migrants (2011)

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See detailLocating Migration: Rescaling Cities and Migrants
Martiniello, Marco ULg

in Contemporary Sociology: A Journal of Reviews (2012), 41(3), 364-365

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See detailLocating transcribed and non-transcribed rDNA spacer sequences within the nucleolus by in situ hybridization and immunoelectron microscopy.
Thiry, Marc ULg; Thiry-Blaise, L.

in Nucleic Acids Research (1991), 19(1), 11-5

Immunoelectron microscopy and in situ hybridization have been used to investigate the precise location of transcribed and non-transcribed rDNA spacer sequences. Whereas a 5'-external transcribed spacer ... [more ▼]

Immunoelectron microscopy and in situ hybridization have been used to investigate the precise location of transcribed and non-transcribed rDNA spacer sequences. Whereas a 5'-external transcribed spacer sequence is predominantly visualized in the fibrillar centers of nucleoli, a non-transcribed spacer sequence is preferentially detected in the interstices, in close contact with the fibrillar centers and which interrupt the surrounding dense fibrillar component. Occasionally these two spacers are also observed in clumps of dense nucleolus-associated chromatin. These observations provide insights into the organization of ribosomal repeats within the nucleolus. [less ▲]

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See detailLocation adjustment for the minimum volume ellipsoid estimator
Croux, C.; Haesbroeck, Gentiane ULg; Rousseeuw, P. J.

in Statistics and Computing (2002), 12(3), 191-200

Estimating multivariate location and scatter with both affine equivariance and positive breakdown has always been difficult. A well-known estimator which satisfies both properties is the Minimum Volume ... [more ▼]

Estimating multivariate location and scatter with both affine equivariance and positive breakdown has always been difficult. A well-known estimator which satisfies both properties is the Minimum Volume Ellipsoid Estimator (MVE). Computing the exact MVE is often not feasible, so one usually resorts to an approximate algorithm. In the regression setup, algorithms for positive-breakdown estimators like Least Median of Squares typically recompute the intercept at each step, to improve the result. This approach is called intercept adjustment. In this paper we show that a similar technique, called location adjustment, can be applied to the MVE. For this purpose we use the Minimum Volume Ball (MVB), in order to lower the MVE objective function. An exact algorithm for calculating the MVB is presented. As an alternative to MVB location adjustment we propose L-1 location adjustment, which does not necessarily lower the MVE objective function but yields more efficient estimates for the location part. Simulations compare the two types of location adjustment. We also obtain the maxbias curves of both L-1 and the MVB in the multivariate setting, revealing the superiority of L-1. [less ▲]

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See detailLocation and Characterization of the Bovine Herpesvirus Type 4 Thymidine Kinase Gene; Comparison with Thymidine Kinase Genes of Other Herpesviruses
Lomonte, P.; Bublot, M.; Pastoret, Paul-Pierre ULg et al

in Archives of Virology (1992), 127(1-4), 327-37

The location and nucleotide sequence of the bovine herpesvirus type 4 (BHV-4) thymidine kinase (TK) gene was determined. The coding region of the TK gene is 1335 nucleotides long and corresponds to a ... [more ▼]

The location and nucleotide sequence of the bovine herpesvirus type 4 (BHV-4) thymidine kinase (TK) gene was determined. The coding region of the TK gene is 1335 nucleotides long and corresponds to a polypeptide of 445 amino acids. Comparison of TK amino acid sequences of BHV-4 and 16 herpesvirus TKs reveals a greater homology to those of the gammaherpesviruses EBV and specially HVS, than to those of alphaherpesviruses. The open reading frames detected in the vicinity of TK gene were homologous to the corresponding ones in other herpesviruses. [less ▲]

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See detailLocation and market area of rail-road terminals
Limbourg, Sabine ULg; Jourquin, Bart

Scientific conference (2010, January 28)

The European transport policy has focused on sustainable transport solutions. One of its objectives for freight transport is to restore the balance between modes and to develop intermodality. Among the ... [more ▼]

The European transport policy has focused on sustainable transport solutions. One of its objectives for freight transport is to restore the balance between modes and to develop intermodality. Among the various types of intermodal transports, this research is concerned with rail-road container terminals embedded in a hub-and–spoke network. These terminals will further be referred to as hubs. Hub-and-spoke networks have been implemented in a number of transportation systems when it is favourable to consolidate and disseminate flows at certain locations called hubs. The efficiency of such a network depends on the location of the hubs. The problem is to find the optimal hub locations and to allocate the remaining nodes to these hubs. This problem is known as the p-hub median problem (p-HMP) where p is the number of hubs to locate. This location-allocation problem is proved to be NP-hard. The time needed to solve it increases as the number of nodes exponent three. Thus, in order to model rail-road transport on the trans-European networks, a subset of nodes that can be considered as good potential locations is needed. We applied the p-HMP to a set of potential locations obtained by both spatial aggregation of demand nodes using hierarchical clustering methods and by a flow-based approach which takes the flows of commodities and their geographic spread into account. They showed that the latest method gives better results and that is why it is retained to determine a set of potential locations. The set of potential locations is used as input for an iterative procedure. One of the main contributions of this research is to propose this iterative procedure based on both the p-HMP and the multi-modal assignment problem. Moreover, the objective function of our p-hub median formulation includes the costs for pre- and post-haulages by road, trans-shipment (according to the number of handled containers into account) and rail haulage. Furthermore, in the p-hub median problem, the total demand is assigned to the hubs. In this research however, the demand can be assigned over all the transportation modes, with the possibility (but not the obligation) of using the trans-shipment facilities. Finally, we presents a methodology able to compare road and rail-road intermodal market areas that takes the network structures, the operation costs and the location of the rail-road terminals into account. This methodology is applied to the optimal configurations obtained by the resolution of the p-HMP and the p-hub centre problem (p-HCP) for the whole trans-European network. Indeed, p-HMP has an efficiency goal by minimizing the total transportation cost. The hub network design obtained by this method can sometimes lead to unsatisfactory results when worst-case origin-destination pairs are separated by a very large distance. Therefore, the p-HCM meets the equity objective by minimizing the maximum cost of a combined transport. [less ▲]

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See detailLocation and Morphology of Io's FUV Footprint Emissions on Jupiter
Grodent, Denis ULg; Gérard, Jean-Claude ULg; Saglam, A. et al

Conference (2005, August 07)

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See detailLocation and Phenotype of Proliferating T cells in Secondary Lymph Follicles
Hoshi, S.; Bouzahzah, F.; Mancini, I. et al

in Journal of Clinical and Experimental Hematopathology [=JCEH] (2001), 42

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See detailLocation and spatial shape of electron beams in Io's wake
Jacobsen, S.; Saur, J.; Neubauer, F. M. et al

in Journal of Geophysical Research. Solid Earth (2010), 115

The Galileo spacecraft observed energetic field-aligned electron beams very close to Io during several flybys. We apply a three-dimensional magnetohydrodynamic (MHD) model of the far-field Io-Jupiter ... [more ▼]

The Galileo spacecraft observed energetic field-aligned electron beams very close to Io during several flybys. We apply a three-dimensional magnetohydrodynamic (MHD) model of the far-field Io-Jupiter interaction to simulate for the first time the location and spatial shape of field-aligned electron beams. Io continuously generates MHD waves by disturbing the Jovian magnetoplasm. Currents carried by Alfven waves propagate predominantly along the magnetic field lines. As the number of charge carriers decreases along the travel path, electrons are accelerated toward Jupiter. These energetic electrons precipitate into the Jovian ionosphere, visible as prominent Io footprint emission. Electrons are also accelerated toward Io and form the equatorial beams observed by the Galileo spacecraft. Unlike the beam formation, the position and spatial structure of these beams have not been addressed in detail before. We use a 3-D MHD model with initial conditions corresponding to the individual Galileo flyby and determine the spatial morphology of the beams in Io's orbital plane. Our results for the beam locations are in good agreement with the Galileo Energetic Particle Detector observations. We find that the ratio of the one-way travel time of the Alfven wave from Io to Jupiter and the convection time of the plasma past the obstacle controls the location of the beam. This leads to the conclusion that at other satellites with other plasma environments, the electrons might not be close to the satellite but can be shifted significantly downstream along its plasma wake. Thus, the future search for electron beams near a satellite should be further extended to the wake region. [less ▲]

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See detailThe location and topology of electron beams in Io‘s wake
Jacobsen, Sven; Saur, Joachim; Neubauer, Friz et al

Conference (2009, April 22)

The Galileo spacecraft measured hot field aligned electron beams near Io during three flybys. We apply our 3D MHD model of the Io-Jupiter interaction to constrain the location and shape of field aligned ... [more ▼]

The Galileo spacecraft measured hot field aligned electron beams near Io during three flybys. We apply our 3D MHD model of the Io-Jupiter interaction to constrain the location and shape of field aligned electron beams for the individual flyby scenarios. Io continuously generates MHD waves by disturbing the Jovian magnetoplasma. Currents carried by Alfvén waves propagate predominantly along the magnetic field lines. The waves accelerate electrons as the number of charge carriers decreases on their way to Jupiter. These energetic electrons precipitate into the Jovian ionosphere, visible as prominent Io footprint emission in the Jovian aurora. On the other hand electrons have to be accelerated upward to form the beams measured by Galileo. Unlike the beam formation, the position and spatial structure of these beams has been poorly discussed. We adopt our 3D MHD model initial conditions to the individual flyby scenario and determine the spatial morphol- ogy of beams in Io’s orbital plane. We compare our findings to Galileo observations and find very good agreement. Moreover, we use our model to further investigate in detail a recent concept which involves cross-hemisphere electron beams to explain certain auroral features of the Io footprint emission such as a leading spot and secondary spots [Bonfond et al., 2008]. Our results indicate that besides geometrical properties, such as Io’s position in the torus, the incoming plasma density controls the travel path and topology of an electron beam. [less ▲]

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See detailLocation estimation in nonparametric regression with censored data
Heuchenne, Cédric ULg; Van Keilegom, Ingrid

in Journal Of Multivariate Analysis (2007), 98(8), 1558-1582

Consider the heteroscedastic model Y =m (X) +sigma(X)epsilon, where epsilon and X are independent, Y is subject to right censoring, m (center dot) is an unknown but smooth location function (like e.g ... [more ▼]

Consider the heteroscedastic model Y =m (X) +sigma(X)epsilon, where epsilon and X are independent, Y is subject to right censoring, m (center dot) is an unknown but smooth location function (like e.g. conditional mean, median, trimmed mean...) and sigma(center dot) an unknown but smooth scale function. In this paper we consider the estimation of m(center dot) under this model. The estimator we propose is a Nadaraya-Watson type estimator, for which the censored observations are replaced by 'synthetic' data points estimated under the above model. The estimator offers an alternative for the completely nonparametric estimator of m (center dot), which cannot be estimated consistently in a completely nonparametric way, whenever high quantiles of the conditional distribution of Y given X = x are involved. We obtain the asymptotic properties of the proposed estimator of m (x) and study its finite samplebehaviour in a simulation study. The method is also applied to a study of quasars in astronomy. (c) 2007 Elsevier Inc. All rights reserved. [less ▲]

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See detailLocation immobilière et T.V.A.
Thilmany, Jean ULg

Book published by Larcier (2009)

La notion de location immobilière en matière de T.V.A. s’écarte expressément des concepts traditionnels du Code civil, et reçoit désormais, pour l’application des directives européennes et des ... [more ▼]

La notion de location immobilière en matière de T.V.A. s’écarte expressément des concepts traditionnels du Code civil, et reçoit désormais, pour l’application des directives européennes et des dispositions de droit interne qui en sont issues, une acception spécifique, la jurisprudence européenne l’ayant érigée en «notion autonome de droit communautaire». Dans cet ouvrage, l’auteur s’attache à cerner les contours de cette notion à la lumière du droit fiscal européen, avant de définir la portée du principe de l’exemption de T.V.A. applicable à la location immobilière. Il analyse ensuite de manière détaillée le régime des diverses formes de mise à disposition d’immeubles qui, par exception, restent néanmoins soumises à la taxe tout en conférant à l’assujetti le droit de déduire les taxes payées en amont, droit exclu en cas d’exemption. Enfin, l’auteur examine le régime de certaines opérations apparentées à la location immobilière et les incidences concrètes, en matière de T.V.A., des travaux effectués par un locataire dans l’immeuble loué, de même que les particularités relatives à la déduction de la T.V.A. par le locataire d’une partie d’immeuble en copropriété forcée. Les nombreuses circulaires et décisions administratives relatives à la matière sont relevées et analysées. Quant aux décisions de jurisprudence, parmi lesquelles un nombre appréciable de décisions inédites, elles font l’objet d’un commentaire systématique. [less ▲]

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See detailLocation of an Ag-NOR protein in Ehrlich tumor cells by immunoelectron microscopy
Thiry, Marc ULg; Vandelaer, M; Goessens, G

Poster (1996)

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See detailLocation of DNA within the nucleolus of rat oocytes during the early stages of follicular growth.
Thiry, Marc ULg; Goessens, Guy ULg

in International Journal of Developmental Biology (1992), 36(1), 139-42

We have investigated the DNA distribution within the rat oocyte nucleolus during the early stages of follicular growth by means of the in situ terminal deoxynucleotidyl transferase method. In the ... [more ▼]

We have investigated the DNA distribution within the rat oocyte nucleolus during the early stages of follicular growth by means of the in situ terminal deoxynucleotidyl transferase method. In the fibrillogranular nucleolus, label is visualized on small clumps of peri- and intranucleolar chromatin. Such labeled clumps are frequently observed inside the interstices surrounding the fibrillar centers. Label is also consistently found in the fibrillar centers whereas the dense fibrillar component and the granular component are devoid of gold particles. These results contradict earlier data but conform with other recent immunocytochemical observations, obtained in nucleoli of a variety of somatic cell types, concerning the correlation between structure and function in the nucleolus. [less ▲]

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