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See detailMG1131 + 0456 - Discovery of the optical Einstein ring with the NTT
Hammer, F.; Angonin, M. C.; Le Fevre, O. et al

in Astronomy and Astrophysics (1991), 250

Deep optical imaging and spectroscopy have been obtained for the well known radio Einstein ring MG1131 + 0456 with the ESO/NTT. The direct CCD frames show a red emission excess at the exact location of ... [more ▼]

Deep optical imaging and spectroscopy have been obtained for the well known radio Einstein ring MG1131 + 0456 with the ESO/NTT. The direct CCD frames show a red emission excess at the exact location of the radio ring. Subsequent subtraction of the lensing galaxy, assumed to be an elliptical galaxy, results in the detection of an optical ring which is strikingly similar to the radio ring. Gravitational lensing models, including source reconstruction, predicts that the source is likely a radio-galaxy for which both the optical and extended radio emissions are sufficiently distorted by the foreground lensing galaxy as to produce a nearly complete ring. The present spectroscopy and broad band photometry suggest that the lensing galaxy has a spectral energy distribution typical of a nonevolved elliptical, tentatively at z of 0.85. The radio-galaxy associated with the radio-ring is likely to be an elliptical at larger redshift, tentatively of 1.13. [less ▲]

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See detailMgII Airglow in the Atmosphere of Venus: Observations and Theory.
Lecompte, M. A.; Paxton, L. J.; Stewart, A. I. F. et al

Conference (1982, June 01)

Not Available

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See detailThe mh gene causing double-muscling in cattle maps to bovine chromosome 2
Charlier, Carole ULg; Coppieters, Wouter ULg; Farnir, Frédéric ULg et al

in Mammalian Genome : Official Journal of the International Mammalian Genome Society (1995), 6

While the hereditary nature of the double-muscling phenotype (a generalized muscular hypertrophy documented in several cattle breeds) is well established, its precise segregation mode has remained ... [more ▼]

While the hereditary nature of the double-muscling phenotype (a generalized muscular hypertrophy documented in several cattle breeds) is well established, its precise segregation mode has remained controversial. Both monogenic models (autosomal dominant or recessive) and oligogenic models have been proposed. Using a panel of 213 bovine microsatellite markers, and an experimental pedigree obtained by backcrossing double-muscled (Belgian Blue)xconventional (Friesian) F1 dams to double-muscled sire, we have mapped a locus on bovine Chromosome (Chr) 2 that accounts for all the phenotypic variance in the backcross generation. This locus, referred to as mh (muscular hypertrophy), has been positioned with respect to a map composed of seven Chr 2-specific microsatellites, at 2 cM from the closest marker. This result confirms the validity in the Belgian Blue population of the monogenic model involving an autosomal mh locus, characterized by a wild-type + and a recessive mh allele, causing the double-muscling phenotype in the homozygous condition. The linkage relationship between the mh locus and the Chr 2 markers was confirmed in three informative pedigrees collected from the general Belgian Blue Cattle population, reinforcing the notion of genetic homogeneity of the double-muscling trait in this breed. This work paves the way towards marker-assisted selection for or against the double-muscling trait, and towards positional cloning of the corresponding gene. [less ▲]

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See detailAn MHD-driven Disk Wind Outflow in SDSS J0300+0048?
Hall, Patrick; Hutsemekers, Damien ULg

in AGN Physics with the Sloan Digital Sky Survey. ASPC 311 (2004, June 01)

The outflow in SDSS J0300+0048 has the highest column density yet reported for a broad absorption line quasar. The absorption from different ions is also segregated as a function of velocity in a way that ... [more ▼]

The outflow in SDSS J0300+0048 has the highest column density yet reported for a broad absorption line quasar. The absorption from different ions is also segregated as a function of velocity in a way that can only be explained by a disk wind outflow. Furthermore, the presence of the such large column densities of gas at the high observed outflow velocities may be incompatible with purely radiative acceleration. MHD contributions to the acceleration should be considered seriously. [less ▲]

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See detailMiao de la tête aux pieds
Eloy, Céline ULg

in Expo-Book Europalia. China (2009)

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See detailMicarea sipmanii, a new species with arbuscular pycnidia from the West Indies
Sérusiaux, Emmanuël ULg; Coppins, Brian J.

in Bibliotheca Lichenologica (2009), 99

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See detailMice lacking the melanin-concentrating hormone receptor-1 exhibit an atypical psychomotor susceptibility to cocaine and no conditioned cocaine response
Tyhon, Alain ULg; Adamantidis, Antoine ULg; Foidart, Agnès ULg et al

in Behavioural Brain Research (2006), 173(1), 94-103

The present study aimed at characterizing the acute and intermittent psychomotor responsiveness to cocaine in mice lacking the MCHR1 receptor, which is thought to modulate the mesocorticolimbic sytem ... [more ▼]

The present study aimed at characterizing the acute and intermittent psychomotor responsiveness to cocaine in mice lacking the MCHR1 receptor, which is thought to modulate the mesocorticolimbic sytem functioning [Smith DG, Tzavara ET, Shaw J, Luecke S, Wade M, Davis R, et al. Mesolimbic dopamine super-sensitivity in melanin-concentrating hormone-1 receptor deficient mice. J Neurosci 2005;25:914-22]. On a first free-drug session, MCHR1-deficient mice exhibited significantly higher levels of locomotor activity elicited by the novelty of the test chambers than their wild-type counterparts. On the following day session, a first injection of 6 or 12mg/kg cocaine induced comparable dose-related psychomotor activations in both genotypes, without significant difference in the relative increase in locomotion. Over the following eight once-daily test sessions, the slight psychomotor increase induced by 6mg/kg was equivalent in both genotypes and constant over the sessions. At 12mg/kg, cocaine induced a clear-cut incremental responsiveness to cocaine in both genotypes on the three first sessions; on the following sessions, only the wild-types displayed an incremental responsiveness until the last session, a sensitized effect that was confirmed for the wild-types but not for the knockouts on a subsequent sensitization test (cocaine challenge). Finally, the knockouts did not exhibit any sign of cocaine-conditioning (saline challenge), contrarily to the wild-types. It is speculated that MCHR1 may contribute to the neurobiological mechanisms of conditioned cocaine-induced psychomotor effects, possibly to those underpinning sensitization, and to a lesser extent to those sub-serving acute pharmacological cocaine action. [less ▲]

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See detailMice overexpressing hsp70 have improved behavior after acute brain injury
Plumier, Jean-Christophe ULg; Popolo, Margherita; Whalen, Michael J. et al

Poster (2001)

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See detailMice Transgenic for a Soluble Form of Murine Cytotoxic T Lymphocyte Antigen 4 Are Refractory to Murine Acquired Immune Deficiency Sydrome Development
de Leval, Laurence ULg; Debrus, S.; Lane, P. et al

in Immunology (1999), 98(4), 630-8

Interactions between B and CD4+ T cells are central to the pathogenesis of retrovirus-induced murine acquired immune deficiency virus (MAIDS). Prompted by previous work showing that treatment with ... [more ▼]

Interactions between B and CD4+ T cells are central to the pathogenesis of retrovirus-induced murine acquired immune deficiency virus (MAIDS). Prompted by previous work showing that treatment with cytotoxic T lymphocyte antigen 4 immunoglobulin (CTLA4Ig) partly inhibited the disease, we studied the course of infection in mice deficient for CD28-B7 interactions (mCTLA4-Hgamma1 transgenic mice). Despite a relative viral load identical to that of non-transgenic mice, the transgenic mice did not develop any of the major MAIDS symptoms (i.e. lymphoproliferation and immune anergy). The mCTLA4-Hgamma1 did not however, completely inhibit B-cell activation as indicated by a slight hypergammaglobulinaemia and microscopic blastic transformation. Absence of MAIDS in transgenic mice was associated with much lower levels of both interleukin-4 and interferon-gamma transcripts following viral infection. These results support the theory that the CD28/B7 costimulatory pathway is a critical determinant to MAIDS development. [less ▲]

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See detailMice with Disrupted Type I Protein Kinase A Anchoring in T Cells Resist Retrovirus-Induced Immunodeficiency
Mosenden, Randi; Singh, Pratibha; Cornez, Isabelle et al

in Journal of Immunology (2011), 186(9), 5119-30

Type I protein kinase A (PKA) is targeted to the TCR-proximal signaling machinery by the A-kinase anchoring protein ezrin and negatively regulates T cell immune function through activation of the C ... [more ▼]

Type I protein kinase A (PKA) is targeted to the TCR-proximal signaling machinery by the A-kinase anchoring protein ezrin and negatively regulates T cell immune function through activation of the C-terminal Src kinase. RI anchoring disruptor (RIAD) is a high-affinity competitor peptide that specifically displaces type I PKA from A-kinase anchoring proteins. In this study, we disrupted type I PKA anchoring in peripheral T cells by expressing a soluble ezrin fragment with RIAD inserted in place of the endogenous A-kinase binding domain under the lck distal promoter in mice. Peripheral T cells from mice expressing the RIAD fusion protein (RIAD-transgenic mice) displayed augmented basal and TCR-activated signaling, enhanced T cell responsiveness assessed as IL-2 secretion, and reduced sensitivity to PGE2- and cAMP-mediated inhibition of T cell function. Hyperactivation of the cAMP–type I PKA pathway is involved in the T cell dysfunction of HIV infection, as well as murine AIDS, a disease model induced by infection of C57BL/6 mice with LP-BM5, a mixture of attenuated murine leukemia viruses. LP-BM5–infected RIADtransgenic mice resist progression of murine AIDS and have improved viral control. This underscores the cAMP–type I PKA pathway in T cells as a putative target for therapeutic intervention in immunodeficiency diseases. [less ▲]

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See detailMice without uPA, tPA, or plasminogen genes are resistant to experimental choroidal neovascularization
Rakic, Jean-Marie ULg; Lambert, Vincent ULg; Munaut, Carine ULg et al

in Investigative Ophthalmology & Visual Science (2003), 44(4), 1732-1739

PURPOSE. To evaluate the presence and potential involvement of members of the plasminogen/plasminogen activator (Plg/PA) system in the exudative form of age-related macular degeneration (AMD). METHODS ... [more ▼]

PURPOSE. To evaluate the presence and potential involvement of members of the plasminogen/plasminogen activator (Plg/PA) system in the exudative form of age-related macular degeneration (AMD). METHODS. The expression of PA members mRNA was evaluated in human and experimental choroidal neovascularization (CNV) by RT-PCR. The presence and activity of PA was studied by immunofluorescence and in situ zymography. The influence of endogenous plasminogen (Plg), urokinase (uPA), tissue type plasminogen activator (tPA), and uPA receptor (uPAR) was explored in single-gene-deficient mice in a model of laser-induced CNV. RESULTS. Members of the Plg/PA system were present both in human and murine CNV. The absence of Pig, uPA, or tPA significantly decreased the development of experimental CNV compared with wild-type or uPAR-deficient mice. This effect could be attributable, partly to a modulation of matrix metalloproteinase activity, but also to an accumulation of fibrinogen-fibrin in the laser-induced wounds. CONCLUSIONS. Together with previous work done by the authors, this study indicates that choroidal neovascularization is extremely sensitive to the modulation of Plg/PA system activity. This may provide a new strategy for the treatment of exudative AMD. [less ▲]

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See detailMicellar electrokinetic chromatography systems for the separation of mixtures of charged and uncharged compounds
Lamalle, Caroline ULg; Servais, Anne-Catherine ULg; Fradi, Ines ULg et al

in Journal of Separation Science (2012), 35(15), 1933-1939

In this study, the migration behavior of charged and uncharged analytes was investigated under different conditions. Effective mobilities - electrophoretic mobilities under the influence of micelles - of ... [more ▼]

In this study, the migration behavior of charged and uncharged analytes was investigated under different conditions. Effective mobilities - electrophoretic mobilities under the influence of micelles - of cations, anions, and neutrals were measured at neutral, basic, and acidic pH (7.5, 11, and 2.2) using background electrolytes containing different sodium dodecyl sulfate (SDS) concentrations (0-90 mM) and acetonitrile (ACN) proportions (0-75%). SDS concentration and ACN proportion were found to have a tremendous effect on the effective mobilities and migration order of the model compounds. Although the SDS micelles preferably interact with neutrals and cations, hydrophobic bonds can also occur with anions. Cations, anions, and neutrals having rather different migration behaviors, it is possible to considerably enhance the selectivity of the method by adjusting properly the SDS concentration and the ACN proportion. These observations confirm the interest of using micellar electrokinetic chromatography not only for the separation of neutral substances but also to analyze charged compounds. [less ▲]

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See detailA micellar route to ordered arrays of magnetic nanoparticles: From size-selected pure cobalt dots to cobalt-cobalt oxide core-shell systems
Boyen, Hans-Gerd; Kästle, Gerd; Zürn, Klaus et al

in Advanced Functional Materials (2003), 13(5), 359-364

Starting with Co-salt-loaded inverse micelles, which form if the diblock copolymer polystyrene-block-poly(2-vinylpyridine) is dissolved in a selective solvent like toluene and CoCl2) is added to the ... [more ▼]

Starting with Co-salt-loaded inverse micelles, which form if the diblock copolymer polystyrene-block-poly(2-vinylpyridine) is dissolved in a selective solvent like toluene and CoCl2) is added to the solution, monomicellar arrays of such micelles exhibiting a significant hexagonal order can be prepared on top of various substrates with tailored intermicellar distances and structure heights. In order to remove the polymer matrix and to finally obtain arrays of pure Co nanoparticles, the micelles are first exposed to an oxygen plasma, followed by a treatment in a hydrogen plasma. Applying in-situ X-ray photoelectron spectroscopy, it is demonstrated that: 1) The oxygen plasma completely removes the polymer, though conserving the original order of the micellar array. Furthermore, the resulting nanoparticles are entirely oxidized with a chemical shift of the Co 2P(3/2) line pointing to the formation Of Co3O4. 2) By the subsequent hydrogen plasma treatment the nanoparticles are fully reduced to metallic Co. 3) By exposing the pure Co nanoparticles for 100 s to various oxygen partial pressures p(O2), a stepwise oxidation is observed with a still metallic Co core surrounded by an oxide shell. The data allow the extraction of the thickness of the oxide shell as a function of the total exposure to oxygen (p(O2) x time), thus giving the opportunity to control the ferromagnetic-antiferromagnetic composition of an exchange-biased magnetic system. [less ▲]

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See detailMicelles CSC étudiées par microscopie à force atomique
Willet, Nicolas ULg; Gohy, Jean-François; Jérôme, Robert ULg

Conference (2002)

Les assemblages supramoléculaires suscitent un grand intérêt parmi la communauté scientifique de nos jours. Un nouveau type de micelles formées dans l’eau est ici rapporté. En effet, dans l’eau, le ... [more ▼]

Les assemblages supramoléculaires suscitent un grand intérêt parmi la communauté scientifique de nos jours. Un nouveau type de micelles formées dans l’eau est ici rapporté. En effet, dans l’eau, le copolymère triséquencé poly(styrène)-b-poly(2-vinylpyridine)-b-poly(oxyde d’éthylène) (PS-b-P2VP-b-POE) forme spontanément des micelles sphériques monodisperses, dont la structure interne a été étudiée par microscopie à force atomique. Dans la plupart des cas d’études supramoléculaires, des copolymères biséquencés amphiphiles sont dissouts dans un solvant sélectif d’un des constituants, ce qui mène à la formation de micelles sphériques consistant en un cœur formé par les blocs insolubles entouré d’une couche des blocs solvatés. On sait que les copolymères triséquencés ABC s’organisent spontanément en une grande variété de structures supramoléculaires à l’état solide, mais leur association dans des solvants sélectifs a été peu rapportée jusqu’ici. Nous rapportons ici la formation de micelles aqueuses constituées de trois couches à partir du copolymère triséquencé PS-b-P2VP-b-POE. Elles ont été baptisées micelles CSC (de l’anglais core-shell-corona). Les masses moléculaires des différents blocs sont 20 000 pour le PS, 14 000 pour la P2VP, et 26 000 pour le POE. Nous nous attendons donc à la formation de micelles CSC consistant en un cœur de PS, une couche intermédiaire de P2VP, et une couronne de POE. De par la dépendance de la solubilité dans l’eau du bloc central de P2VP vis-à-vis du degré d’ionisation, les micelles CSC devraient être sensibles au pH. La structure des micelles CSC à l’état sec a été étudiée par microscopie à force atomique (AFM) en mode tapping. Ces observations complètent une étude par microscopie électronique à transmission (TEM). A pH>5, des micelles sphériques, hautement régulières et de faible polydispersité sont observées, en accord avec les études de diffusion de lumière dynamique (DLS) et de TEM. Le diamètre des micelles CSC à l’état sec a été mesuré (DCSC  60 nm). Cette valeur est logiquement inférieure au diamètre hydrodynamique (Dh  75 nm, par DLS), car la couronne de POE est désolvatée. A pH<5, l’image AFM des micelles CSC montre qu’elles ont des dimensions caractéristiques (DCore  30 nm et DCore+Shell  40 nm) qui sont en accord qualitatif avec celles estimées via les images TEM. Les nanoparticules métalliques et semi-conductrices sont les nouveaux candidats idéaux pour l’électronique, les nanosystèmes optiques, etc. De telles nanoparticules peuvent être synthétisées dans des réacteurs confinés tels que les cœurs micellaires de copolymères séquencés amphiphiles, avec l’inconvénient que la taille de la nanoparticule, qui est fixée par les dimensions du cœur micellaire, ne peut varier que dans une gamme limitée à quelques nanomètres. Bien au contraire, les blocs P2VP des micelles CSC peuvent être utilisés comme un moule pour la production de nanocouches métalliques, dont l’épaisseur peut être ajustée par la masse moléculaire du bloc de P2VP. La couche de P2VP a été sélectivement chargée d’ions AuCl4–, grâce à l’interaction sélective entre les ions et les unités 2VP protonnées. L’excès d’ions AuCl4– n’interagissant pas a été éliminé par dialyse, suivie par la réduction des centres Au3+ en Au0, par irradiation électronique ou par NaBH4. Les micelles chargées d’or ont une structure uniforme. Cependant, des expériences d’absorption UV-visible mettent en évidence la persistance de particules d’or individuelles au sein de la couche de P2VP. Il ne se forme donc pas de mur d’or continu. Il reste à optimiser les conditions de chargement en HAuCl4 des micelles CSC et de réduction. En complémentarité avec d’autres techniques, l’AFM nous a donc permis d’observer que le copolymère triséquencé PS(20 000)-b-P2VP(14 000)-b-POE(26 000) forme des micelles bien définies. La couche de P2VP peut servir de réacteur pour la synthèse de nanoparticules d’or. Enfin, la couche de P2VP, sensible au pH, rend ce système utile pour l’encapsulation et/ou le relargage de principes actifs. [less ▲]

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See detailMicellization of Poly(2-oxazoline)-Based Quasi-Diblock Copolymers on Surfaces
Fustin, Charles-André; Lefèvre, Nathalie ULg; Hoogenboom, Richard et al

in Macromolecular Chemistry and Physics (2007), 208

The micellization on surfaces of two series of quasi-diblock copoly(2-oxazoline)s consisting of 2-phenyl-2-oxazoline (PhOx) segments linked to either 2-methyl-2-oxazoline (MeOx) or 2-ethyl-2-oxazoline ... [more ▼]

The micellization on surfaces of two series of quasi-diblock copoly(2-oxazoline)s consisting of 2-phenyl-2-oxazoline (PhOx) segments linked to either 2-methyl-2-oxazoline (MeOx) or 2-ethyl-2-oxazoline (EtOx) segments is investigated in detail. Those micelles are not preexisting in the initial ethanol solution but are formed during the spin-coating process by the evaporation of the solvent inducing the precipitation of the less soluble PhOx segments. The morphology and size of the surface micelles vary according to the fraction of PhOx in the copolymers. Moreover, it is demonstrated that the chemical nature of the more soluble MeOx or EtOx segments also has an influence on the morphology of the resulting surface micelles. [less ▲]

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See detailMicellization of quaternized poly(2-(dimethylamino)ethyl methacrylate)-block-poly(methyl methacrylate) copolymers in water
Antoun, Sayed; Gohy, Jean-François; Jérôme, Robert ULg

in Polymer (2001), 42(8), 3641-3648

Micellization of a series of amphiphilic quaternized poly(2-(dimethylamino)ethyl methacrylate)-block-poly(methyl methacrylate) (PQDMAEMA-b-PMMA) copolymers has been studied in water. The alkyl halide used ... [more ▼]

Micellization of a series of amphiphilic quaternized poly(2-(dimethylamino)ethyl methacrylate)-block-poly(methyl methacrylate) (PQDMAEMA-b-PMMA) copolymers has been studied in water. The alkyl halide used for the quaternization of the aminated block has an effect on the solution properties of the diblocks, that have been investigated by dynamic light scattering and surface tension measurements. When a short length alkyl halide is used, the diblock copolymers behave like traditional amphiphiles, whereas their behavior is similar to polysoaps in case of long alkyl halides. The size of the micelles increases when 1-bromopropan-3-ol is substituted for 1-bromopropane in the quaternization reaction. It is, however, independent of the structure of butyl bromide, i.e. n-butyl vs tert-butyl bromide. The solution properties of a star-shaped PQDMAEMA-b-PMMA copolymer have also been studied and compared to the linear counterpart. The star-shaped architecture actually prevents the block copolymer to be properly oriented at the air/water interface in agreement with the formation of unimer micelles. [less ▲]

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See detailMichael Gizzi, New Depths of Deadpan
Delville, Michel ULg

in Sentence: A Journal of Prose Poetics (2009), 7

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