Les sources pour l’Histoire de l’architecture des Temps modernes en Wallonie

Scientific conference (2010, December 03)

Du "on dit" de la rumeur au "cela est" de l'information. Réflexion sur la nature fragmentaire de l'énonciation mass-médiatique

Conference (2010, December 03)

Comment se négocie la construction d'un lieu de culte dans l'espace urbain? Le cas du projet de mosquée à Glain

Conference (2010, December 02)

Use of tolerance intervals in the development of near infrared spectroscopic methods: An innovative way to select the most appropriate calibration model

Poster (2010, December 02)

Evaluating analytical results reliability using a Bayesian probability criterion

Poster (2010, December 02)

In pharmaceutical industries, quantitative analytical methods such as HPLC play a key role. Indeed, the analytical results obtained from them are used to make crucial decisions such as the release of ... [more ▼]

In pharmaceutical industries, quantitative analytical methods such as HPLC play a key role. Indeed, the analytical results obtained from them are used to make crucial decisions such as the release of batches of drugs, the evaluation of safety and efficacy of new drug candidates or the monitoring of patients health. Prior to their routine use, analytical methods are submitted to a stringent validation study where they have to demonstrate that they are fit for their final purpose, i.e. providing accurate result . Typically this demonstration is made by either providing point estimates of systematic error (bias) and random error (variance) or sometimes by providing interval estimates of these statistical parameters at several well defined concentration levels of the target analyte. They are then compared to maximum acceptable levels. More recently, tolerance intervals approaches have been proposed that are evaluated in a similar way at these key concentration levels. However none of these decision approaches allow knowing the probability to obtain accurate results over the whole concentration range of interest. Frequentist approximations have been proposed to estimate this probability but only at the concentration levels experimentally tested and not for the whole range of interest. In this work, a linear hierarchical Bayesian approach is proposed. It takes into account the potential random characteristic of the slope and intercept observed from one analytical run to the other, and also integrates the possible covariance between the parameters. Additionally, heteroscedasticity of the residual variance over the concentration range investigated is taken into account. A situation regularly observed in practice. Finally a reliability profile for the whole concentration range studied is obtained using MCMC sampling. This profile provides the probability (Prel) to obtain accurate results over the full concentration range investigated. This profile is then compared to a minimum reliability probability (Pmin) that will define the valid concentration range of the analytical method. The usefulness of this approach is illustrated through the validation of a bioanalytical method and also compared with a one concentration level at a time frequentist approach derived from tolerance intervals. [less ▲]

Buñuel et le sombrero mexicain

Conference (2010, December 02)

La conférence analyse quelques aspects de la relation entre Buñuel et la culture mexicaine officielle. D'abord on analyse le discours du cinéaste lui-même sur ce qu'il appelait la 'culture du sombrero ... [more ▼]

La conférence analyse quelques aspects de la relation entre Buñuel et la culture mexicaine officielle. D'abord on analyse le discours du cinéaste lui-même sur ce qu'il appelait la 'culture du sombrero'. Ensuite on lit les textes que le poète Octavio Paz écrivit sur le cinéaste espagnol. [less ▲]

Sustainable Strategy and Related Performance Management in Small Firms: A Belgian Case Study

Conference (2010, December 02)

Les règles d’interprétation en droit fiscal à la lumière de la jurisprudence des juridictions supérieures

Scientific conference (2010, December 02)

Crises alimentaires et climatiques au Niger : Bilan et perspectives à l'occasion du Sommet de Cancun sur le réchauffement climatique

Scientific conference (2010, December 01)

Hard X-ray identification of η Carinae and steadiness close to periastron

in Astronomy and Astrophysics (2010), 524

Context. The colliding-wind binary η Carinae exhibits soft X-ray thermal emission that varies strongly around the periastron passage. It has been found to have non-thermal emission, thanks to its ... [more ▼]

Context. The colliding-wind binary η Carinae exhibits soft X-ray thermal emission that varies strongly around the periastron passage. It has been found to have non-thermal emission, thanks to its detection in hard X-rays using INTEGRAL and Suzaku, and also in γ-rays with AGILE and Fermi. <BR /> Aims: This paper attempts to definitively identify η Carinae as the source of the hard X-ray emission, to examine how changes in the 2-10 keV band influence changes in the hard X-ray band, and to understand more clearly the mechanisms producing the non-thermal emission using new INTEGRAL observations obtained close to periastron passage. <BR /> Methods: To strengthen the identification of η Carinae with the hard X-ray source, a long Chandra observation encompassing the INTEGRAL/ISGRI error circle was analysed, and all other soft X-ray sources (including the outer shell of η Carinae itself) were discarded as likely counter-parts. To expand the knowledge of the physical processes governing the X-ray lightcurve, new hard X-ray images of η Carinae were studied close to periastron, and compared to previous observations far from periastron. <BR /> Results: The INTEGRAL component, when represented by a power law (with a photon index Γ of 1.8), would produce more emission in the Chandra band than observed from any point source in the ISGRI error circle apart from η Carinae, as long as the hydrogen column density to the ISGRI source is lower than N[SUB]H[/SUB] ≲ 10[SUP]24[/SUP] cm[SUP]-2[/SUP]. Sources with such a high absorption are very rare, thus the hard X-ray emission is very likely to be associated with η Carinae. The eventual contribution of the outer shell to the non-thermal component also remains fairly limited. Close to periastron passage, a 3-σ detection is achieved for the hard X-ray emission of η Carinae, with a flux similar to the average value far from periastron. <BR /> Conclusions: Assuming a single absorption component for both the thermal and non-thermal sources, this 3-σ detection can be explained with a hydrogen column density that does not exceed N[SUB]H[/SUB] ≲ 6 × 10[SUP]23[/SUP] cm[SUP]-2[/SUP] without resorting to an intrinsic increase in the hard X-ray emission. The energy injected in hard X-rays (averaged over a month timescale) appears to be rather constant at least as close as a few stellar radii, well within the acceleration region of the wind. [less ▲]