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See detailA close look at the RGS spectra of the O4Ief star Zeta Pup
Rauw, Grégor ULg; Flores, A.; Nazé, Yaël ULg et al

Poster (2010)

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See detailClose projected QSO-Galaxy associations: are they real?
Claeskens, Jean-François ULg; Surdej, Jean ULg

in Astronomy and Astrophysics (1998), 335

The present status of close projected associations between high redshift quasars and foreground galaxies is reviewed in the framework of gravitational lensing, adopting both an observational and a ... [more ▼]

The present status of close projected associations between high redshift quasars and foreground galaxies is reviewed in the framework of gravitational lensing, adopting both an observational and a theoretical approach. The Non Singular Isothermal Spherical lens model (Hinshaw & Krauss 1987) is used. We confirm that a stronger overdensity q of bright galaxies is expected at small projected angular separations (<= 3arcsec ) from high redshift and bright (thus highly luminous) quasars (HLQs). The effects of a non singular galactic core radius and/or microlensing only slightly enhance this expected overdensity. The predictions reproduce pretty well the scarce observations which are presently available, with the exception of two rather high overdensities previously claimed in the literature (e.g. q=2.9 for theta <= 6arcsec , Webster & Hewett 1990). Uncontrolled morphological selections may affect these controversial results so that additional unbiased observations are badly needed before rejecting gravitational lensing as the mechanism to produce the observed close angular QSO-galaxy associations. We describe three new selected and bias-free samples consisting of a total of 219 different HLQs. Although an apparent overdensity is detected in two of them, these galaxy excesses are found to be statistically not significant. Firm confirmation of the reality of close projected QSO-Galaxy associations is hampered by small number statistics: the expected and observed absolute numbers of such QSO-galaxy associations are still presently found to be very small. Therefore, the corresponding error bars are quite large. We conclude that the best observational strategy to significantly detect (at 3sigma ) an overdensity of galaxies near HLQs is to observe about 1500 HLQs (M_V ~ -29) down to a limiting magnitude Rlim ~ 23. Future automated surveys may provide us with such a large and unbiased database. In conclusions, we find that the lensing-induced correlation between galaxies and HLQs at small angular separations consists of a very interesting but weak effect, much less sensitive to cosmological or astrophysical parameters than the number of multiply imaged sources expected within a sample of HLQs. Based on data collected at the European Southern Observatory, La Silla, Chile [less ▲]

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See detailClose-packed array of gold nanoparticles and Sum Frequency Generation spectroscopy in total internal reflection: A platform for studying biomolecules and biosensors
Tourillon, Gérard; Dreesen, Laurent ULg; Volcke, Cédric et al

in Journal of Materials Science (2009), 44(24), 6805-6810

An approach is introduced for studying the adsorption and recognition mechanisms of biomolecules, without using any markers. We show for the first time, that the Sum Frequency Generation spectroscopy ... [more ▼]

An approach is introduced for studying the adsorption and recognition mechanisms of biomolecules, without using any markers. We show for the first time, that the Sum Frequency Generation spectroscopy performed in the Total Internal Reflection (TIR-SFG) geometry, combined with a regular close-packed array of gold nanoparticles allows to probe with a high sensitivity the changes in conformation and orientation induced by the recognition process of avidin by biocytin. This approach represents a new platform with potential use in biosensors, diagnostics and bioactive layers. [less ▲]

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See detailClose-up of primary and secondary asteroseismic CoRoT targets and the ground-based follow-up observations
Uytterhoeven, K.; Poretti, E.; Rainer, M. et al

in Journal of Physics Conference Series (2008), 118

To optimise the science results of the asteroseismic part of the CoRoT satellite mission a complementary simultaneous ground-based observational campaign is organised for selected CoRoT targets. The ... [more ▼]

To optimise the science results of the asteroseismic part of the CoRoT satellite mission a complementary simultaneous ground-based observational campaign is organised for selected CoRoT targets. The observations include both high-resolution spectroscopic and multicolour photometric data. We present the preliminary results of the analysis of the ground-based observations of three targets. A line-profile analysis of 216 high-resolution FEROS spectra of the δ Sct star HD 50844 reveals more than ten pulsation frequencies in the frequency range 5-18 d[SUP]-1[/SUP], including possibly one radial fundamental mode (6.92 d[SUP]-1[/SUP]). Based on more than 600 multi-colour photometric datapoints of the β Cep star HD 180642, spanning about three years and obtained with different telescopes and different instruments, we confirm the presence of a dominant radial mode ν[SUB]1[/SUB] = 5.48695 d[SUP]-1[/SUP], and detect also its first two harmonics. We find evidence for a second mode ν[SUB]2[/SUB] = 0.3017 d[SUP]-1[/SUP], possibly a g-mode, and indications for two more frequencies in the 7-8 d[SUP]-1[/SUP] domain. From Stromgren photometry we find evidence for the hybrid 5 Sct/γ Dor character of the F0 star HD 44195, as frequencies near 3 d[SUP]-1[/SUP] and 21 d[SUP]-1[/SUP] are detected simultaneously in the different filters. [less ▲]

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See detailA closed form technique to predict springback in creep age-forming
Jeunechamps, Pierre-Paul ULg; Ho, K. C.; Lin, J. et al

in International Journal of Mechanical Sciences (2006), 48(6), 621-629

An efficient numerical method has been developed and programmed to predict springback in creep age-forming (CAF) of alummium shell components. Physically based unified creep-ageing constitutive equations ... [more ▼]

An efficient numerical method has been developed and programmed to predict springback in creep age-forming (CAF) of alummium shell components. Physically based unified creep-ageing constitutive equations determined for AA7010 at 150 degrees C are used to evaluate age-hardening and creep deformation in CAF processes. The studies are mainly concentrated on the pure bending of aluminium plates. Effects of plate thickness, single and double curvature bending, ageing time and stress relaxation features on springback are investigated. It is shown that the proposed algorithm can predict springback accurately and gives a relationship between geometrical data and springback. (c) 2006 Elsevier Ltd. All rights reserved. [less ▲]

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See detailClosed-form dual perturb and combine for tree-based models
Geurts, Pierre ULg; Wehenkel, Louis ULg

in Proceedings of the International Conference on Machine Learning (ICML 2005) (2005)

This paper studies the aggregation of predictions made by tree-based models for several perturbed versions of the attribute vector of a test case. A closed-form approximation of this scheme combined with ... [more ▼]

This paper studies the aggregation of predictions made by tree-based models for several perturbed versions of the attribute vector of a test case. A closed-form approximation of this scheme combined with cross-validation to tune the level of perturbation is proposed. This yields soft-tree models in a parameter free way, and reserves their interpretability. Empirical evaluations, on classification and regression problems, show that accuracy and bias/variance tradeoff are improved significantly at the price of an acceptable computational overhead. The method is further compared and combined with tree bagging. [less ▲]

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See detailClosed-Loop Learning of Visual Control Policies
JODOGNE, Sébastien ULg

Doctoral thesis (2006)

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See detailClosed-Loop Learning of Visual Control Policies
Jodogne, Sébastien ULg; Piater, Justus ULg

in Journal of Artificial Intelligence Research (2007), 28

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See detailClosed-loop model of the cardiovascular system including ventricular interaction and valve dynamics: application to pulmonary embolism
Desaive, Thomas ULg; Dutron, S.; Lambermont, Bernard ULg et al

in 12th International Conference on Biomedical Engineering (2005)

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See detailClosed-loop transient stability emergency control
Ernst, Damien ULg; Pavella, Mania ULg

in Proceedings of the IEEE Power Engineering Society Winter Meeting 2000 (2000)

The question of transient stability control is revisited, various types of controls are identified, and a general approach to closed-loop emergency control is proposed. The focus is on feasibility aspects ... [more ▼]

The question of transient stability control is revisited, various types of controls are identified, and a general approach to closed-loop emergency control is proposed. The focus is on feasibility aspects, general salient features and illustration of stabilization capabilities of an emergency control scheme relying on generation shedding. [less ▲]

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See detailA closer eye on hedge funds' dynamic hedging
Babaei, Hamid; Muller, Aline ULg; Lambert, Marie ULg

Conference (2013, April 18)

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See detailA closer look at the low frequency dynamics of vortex matter
Raes, Bart; de Souza Silva, Clecio C.; Silhanek, Alejandro ULg et al

in Physical Review. B : Condensed Matter (2014), 90

Using scanning susceptibility microscopy, we shed new light on the dynamics of individual superconducting vortices and examine the hypotheses of the phenomenological models traditionally used to explain ... [more ▼]

Using scanning susceptibility microscopy, we shed new light on the dynamics of individual superconducting vortices and examine the hypotheses of the phenomenological models traditionally used to explain the macroscopic ac electromagnetic properties of superconductors. The measurements, carried out on a 2H-NbSe2 single crystal at relatively high temperature T = 6.8 K, show a linear amplitude dependence of the global ac-susceptibility for excitation amplitudes between 0.3 and 2.6 Oe. We observe that the low amplitude response, typically attributed to the oscillation of vortices in a potential well defi ned by a single, relaxing, Labusch constant, actually corresponds to strongly non-uniform vortex shaking. This is particularly pronounced in the fi eld-cooled disordered phase, which undergoes a dynamic reorganization above 0.8 Oe as evidenced by the healing of lattice defects and a more uniform oscillation of vortices. These observations are corroborated by molecular dynamics simulations when choosing the microscopic input parameters from the experiments. The theoretical simulations allow us to reconstruct the vortex trajectories providing deeper insight in the thermally induced hopping dynamics and the vortex lattice reordering. [less ▲]

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See detailClosing address for the session "Bullks and Characterization"
Vanderbemden, Philippe ULg

Conference (2010, November)

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See detailClostridia and enterotoxaemia
Mainil, Jacques ULg

Conference (2006)

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See detailClostridial brain abscess after glioblastoma resection: case report and critical review of the literature
Duntze, J; Litré, Claude Fabien ULg; Bajolet, O et al

in Neuro-Chirurgie (2009), 55(6), 569-72

Clostridium perfringens is rare in neurosurgery. The source of clostridial brain abscess is usually a penetrating head injury. We report the case of a 57-year-old man who had parietal glioblastoma ... [more ▼]

Clostridium perfringens is rare in neurosurgery. The source of clostridial brain abscess is usually a penetrating head injury. We report the case of a 57-year-old man who had parietal glioblastoma resection with local carmustine chemotherapy and who presented a clostridial brain abscess three weeks later. Progression was especially brutal, leading to patient's death in few hours. We discuss the etiology and progression of this case compared to the data reported in the literature. [less ▲]

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See detailClostridies humaines et animales
Mainil, Jacques ULg

Scientific conference (2004, May)

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See detailClostridium difficile in young farm animals and slaughter animals in Belgium
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Vandebroek, Johan et al

in Anaerobe (2012), 18(6), 621-625

Faecal carriage of Clostridium difficile in healthy animals has been reported recently, especially in piglets and calves. However there is limited data about carriage in animals just prior to slaughter in ... [more ▼]

Faecal carriage of Clostridium difficile in healthy animals has been reported recently, especially in piglets and calves. However there is limited data about carriage in animals just prior to slaughter in Europe. The main objective of this study was to determine the presence of C. difficile in pigs and cattle at the slaughterhouse. C. difficile was isolated in 6.9% of the cattle at the slaughterhouse. None of the pig slaughter samples were positive for C. difficile after an enrichment time of 72 h. For complementary data, a short study was conducted in piglets and calves at farms. C. difficile was more prevalent in piglets (78.3%) than in calves (22.2%) on the farms. Regarding the piglet samples, 27.8% of the positive samples were detected without enrichment of stools. The PCR ribotype 078 was predominant in farm animals. Samples isolated from slaughter cattle presented the widest range in PCR-ribotype variety, and the most prevalent PCR ribotype was 118a UCL. The results of this study confirm that C. difficile is present in slaughter animals in Belgium with a large percentage of toxigenic strains also commonly found in humans. [less ▲]

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See detailClostridium difficile: an emerging zoonotic pathogen ?
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Avesani, Véronique et al

Conference (2013, November 21)

Clostridium difficile is an anaerobic, spore-forming bacterium that remains the main cause of nosocomial diarrhoea in humans after use of antibiotics. C. difficile has also been described in other ... [more ▼]

Clostridium difficile is an anaerobic, spore-forming bacterium that remains the main cause of nosocomial diarrhoea in humans after use of antibiotics. C. difficile has also been described in other environments outside of hospitals, such as soil, river and seawater samples (Pasquale et al., 2011) and in animals, in which it can also cause enteric disease (Songer and Anderson, 2006). The possibility of transmission of C. difficile pathogenic isolates between animals, environments and humans has been suggested (Janezic et al., 2012). In recent years, the interest in C. difficile in food and in food animals has increased, leading to studying animals as a possible reservoir and a potential risk for food borne infections linked to C. difficile. Studies in various countries have determined differences in the prevalence of C. difficile in animals just before slaughter (Houser et al., 2012; Rodriguez et al., 2012) as well as in retail meat (Houser et al., 2012). In addition, many types, including PCR-ribotype 078, are present in humans, animals and meat (Janezic et al.; Weese et al., 2009). The objective of this study was to evaluate the presence of C. difficile at the slaughterhouse and in retail meat. Intestinal and carcass samples were collected from pigs and cattle at a single slaughterhouse. Raw meat (beef and pork) was obtained from the retail trade. C. difficile was isolated in 1% and 9.9% of the pig and cattle intestinal contents and in 7.9% and 7% of cattle and pig carcass samples respectively. From retail meat, C. difficile was recovered from 2.3% of the beef samples and from 4.7% of the pork samples. A total of 21 different PCR-ribotypes were identified with a large percentage of types 078 and 014. This study confirms that animals are carriers of C. difficile at slaughter, and that carcass contamination occurs inside the slaughterhouse. Furthermore the results obtained also reveal the presence of toxigenic C. difficile in retail meat in Belgium with a predominance of isolates correlated with the PCR-ribotypes involved in human C. difficile infections. [less ▲]

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