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See detailRevisiting the SN1987A gamma-ray limit on ultralight axion-like particles
Payez, Alexandre ULg; Evoli, Carmelo; Fischer, Tobias et al

in Journal of Cosmology and Astroparticle Physics [= JCAP] (2015), 2015(02), 006

We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and ... [more ▼]

We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling: g_{a\gamma} < 5.3 x 10^{-12} GeV^{-1}, for m_a < 4.4 x 10^{-10} eV, and we also give its dependence at larger ALP masses. Moreover, we discuss how much the Fermi-LAT satellite experiment could improve this bound, should a close-enough supernova explode in the near future. [less ▲]

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See detailSingle Wavelength Coarse Phasing In Segmented Telescopes
Simar, Juan Felipe ULg

in Applied Optics (2015), 54

Space observations of fainter and more distant astronomical objects constantly require telescope primary mirrors with a larger size. The diameter of monolithic primary mirrors is limited to 10 m because ... [more ▼]

Space observations of fainter and more distant astronomical objects constantly require telescope primary mirrors with a larger size. The diameter of monolithic primary mirrors is limited to 10 m because of manufacturing limitations. For space telescopes, the primary mirrors are limited to less than 5 m due to fairing capacity. Segmented primary mirrors thus constitute an alternative solution to deal with the steadily increase of the primary mirror size. The optical path di erence between the individual segments must be close to zero (few nm) in order to be di raction limited. We propose in this paper a new inter-segment piston sensor based on coherence measurement of a star image. This sensor is intended to be used in the co-phasing system of future segmented mirrors. [less ▲]

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See detailComment les disciplines se reconstruisent dans des environnements hybrides et dynamiques
Fallon, Catherine ULg; Thoreau, François ULg

Scientific conference (2015, February 06)

Les chercheurs en sciences politiques et sociales, voire les philosophes politiques, sont de plus en plus souvent « embarqués » dans des projets résolument transdisciplinaires, portés par les groupes de ... [more ▼]

Les chercheurs en sciences politiques et sociales, voire les philosophes politiques, sont de plus en plus souvent « embarqués » dans des projets résolument transdisciplinaires, portés par les groupes de recherche de différentes disciplines, engagés dans les développement scientifico-technologiques les plus pointus, que ce soit dans le secteur des nanotechnologies ou des biotechnologies médicales (pour citer deux exemples récents,Thoreau 2013) . Cet article prend comme point de départ un projet pluriannuel qui a obtenu des subsides pour plonger pendant une longue période trois chercheurs (philosophe, anthropologue, politologue) dans un centre de recherche en génomique humaine appliquée, installé dans une aile du Centre-Hospitalo-Universitaire. En tant que coordinateurs de ce projet, nous voulons aborder ab initio (1) la question des conditions d’exercice de notre démarche de terrain et (2) les conditions de notre service en tant que politologues au fil de cette trajectoire. [less ▲]

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See detailComprendre les programmes électoraux : comparaison des méthodes d’encodage manuel et automatique
Piet, Grégory ULg; Dandoy, Régis; Joly, Jeroen

Conference (2015, February 06)

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See detailMédias et dette wallonne: polémique autour d'un indicateur de finances publiques
Piron, Damien ULg

Conference (2015, February 06)

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See detailA mixed integer nonlinear programming bi-objective model for intermodal network design
Mostert, Martine ULg; Caris, An; Limbourg, Sabine ULg

Conference (2015, February 05)

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See detailOpinions, attitudes et comportements politiques. Notes de cours
Grandjean, Geoffrey ULg

Learning material (2015)

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See detailPolitical Opinions, Attitudes and Behaviours
Grandjean, Geoffrey ULg

Learning material (2015)

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See detail18F-FPRGD2 PET/CT imaging of integrin αvβ3 in renal carcinomas: Correlation with histopathology
WITHOFS, Nadia ULg; SIGNOLLE, NICOLAS; SOMJA, Joan ULg et al

in Journal of Nuclear Medicine (The) (2015)

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See detailRésistance aux antibiotiques : le retour à l’ère prébiotique ?
Galleni, Moreno ULg; Kerff, Frédéric ULg; Rigali, Sébastien ULg

Conference (2015, February 05)

Aujourd’hui, la résistance des bactéries aux antibiotiques relève d'une préoccupation croissante dans le domaine de la santé publique et s'impose plus que jamais comme une priorité. Ce problème a un coût ... [more ▼]

Aujourd’hui, la résistance des bactéries aux antibiotiques relève d'une préoccupation croissante dans le domaine de la santé publique et s'impose plus que jamais comme une priorité. Ce problème a un coût, sociétal et économique en Europe: 25.000 décès annuels par septicémie et 1,5 milliard d’euros d’augmentation du coût des traitements. Bien que le besoin de nouveaux agents antibactériens en milieu clinique est urgent, seules deux nouvelles classes d’antibiotiques ont pu être proposées durant ces 30 dernières années. En effet, la découverte et le développement de nouveaux antibiotiques posent des défis scientifiques, cliniques et financiers importants. [less ▲]

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See detailDaily intake and bacteriological quality of meat consumed in the households of Kigali city (Rwanda)
Niyonzima, Eugène; Ongol, Martin Patrick; Kimonyo, Anasthase et al

Poster (2015, February 05)

Meat is worldwidely known to be a nutrient rich food. It provides valuable amounts of proteins,vitamins such as retinol and vitamin B12 and minerals namely iron, selenium and zinc with an increased ... [more ▼]

Meat is worldwidely known to be a nutrient rich food. It provides valuable amounts of proteins,vitamins such as retinol and vitamin B12 and minerals namely iron, selenium and zinc with an increased bioavailability than found in other dietary sources [1]. Along the production chain, meat can get contaminated by a wide range of spoilage and/or pathogenic microorganisms from the farm, slaughtering environment and distribution. The actual number of foodborne infections attributable to meat is difficult to assess accurately, principally because only a small proportion of illness cases is officially reported. However, by using outbreak data published internationally, Greig and Ravel [2] reported that 12.7 % of reported foodborne outbreaks were attributable to beef while 10.5 and 4.6 % were associated with chicken and pork, respectively. According to the same authors, Salmonella spp. and pathogenic E.coli, respectively, were identified as the causal agents in 32.9 and 34.6 % of foodborne outbreaks of bacterial origin attributable to beef. The objective of this study was to determine the meat consumption pattern in different socio-conomical categories of the population of Kigali city and to assess the bacteriological quality of the consumed meat. [less ▲]

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See detailQuaternary prevention, an answer of family doctors to overmedicalization
Jamoulle, Marc ULg

in International Journal of Health Policy and Management (2015), 4((X)), 1-4

In response to the questioning of Health Policy and Management (HPAM) by colleagues on the role of rank and file family physicians in the same journal, the author, a family physician in Belgium, is trying ... [more ▼]

In response to the questioning of Health Policy and Management (HPAM) by colleagues on the role of rank and file family physicians in the same journal, the author, a family physician in Belgium, is trying to highlight the complexity and depth of the work of his colleagues and their contribution to the understanding of the organization and economy of healthcare. It addresses, in particular, the management of health elements throughout the ongoing relationship of the family doctor with his/her patients. It shows how the three dimensions of prevention, clearly included in the daily work, are complemented with the fourth dimension, quaternary prevention or prevention of medicine itself, whose understanding could help to control the economic and human costs of healthcare [less ▲]

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See detailMechanisms of metal hyperaccumulation in A. halleri
Hanikenne, Marc ULg

Scientific conference (2015, February 04)

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See detailLo “stratega” delle immagini. Cosimo I de’ Medici e gli artisti della Firenze ducale
Geremicca, Antonio ULg

Conference given outside the academic context (2015)

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See detailSite-specific height-diameter allometry of Central African moist forests
Loubota Panzou, Grâce Jopaul ULg; Doucet, Jean-Louis ULg; Fayolle, Adeline ULg

Poster (2015, February 04)

In this study we aimed to identify the variation in height-diameter allometry between forest types and among species in Central African moist forests. We also examined the consequences on biomass ... [more ▼]

In this study we aimed to identify the variation in height-diameter allometry between forest types and among species in Central African moist forests. We also examined the consequences on biomass estimation. Two forest sites in southern Cameroon with contrasting levels of deciduousness. Height and diameter were measured for a total of 521 trees belonging to 12 timber species over a large range of diameter, 10-240 cm for the Ma’an site and 11-182 cm for the Mindourou site. Non-destructive height measurements were calibrated with destructive measurements for a total of 60 trees, 30 in each site. Commercial forest inventory data (n=7253 0.5ha plots) were gathered for the Ma’an (n=34 samples and 2101 plots) and Mindourou (n=117 samples and 5152 plots) sites. A total of ten allometric models (including asymptotic and non-asymptotic models) were fitted to the height-diameter data at species (n=12) and site (n=2) level. Biomass estimates were computed based on forest inventory data and general allometric models using both site-specific and published height-diameter equations. Given the strong correlation between the non-destructive and destructive height measurements we had confidence in using the non-destructive height measurements to establish site- and species-specific height-diameter allometric equations. The height measurements performed over a wide range of diameters, 10-240 cm, tended to support an asymptotic shape (and most often the Michaelis Menten model) for the height-diameter allometry either at species and site level. We identified a significant difference in height-diameter allometry between the two study sites. For a given diameter, trees tended to be taller in the more semi-deciduous Mindourou site than in the more evergreen Ma’an site, with a maximum height of 39.5 and 46.5 m, respectively. The two sites significantly differed in stand structure and biomass. This difference is due to the variation in height-diameter allometry. Height-diameter allometry strongly varies between sites and site-specific height-diameter allometric equations should be developed to further improve the estimation of biomass and carbon stock contained in tropical forests. [less ▲]

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See detailSuppression of Limit Cycle Oscillations using the Nonlinear Tuned Vibration Absorber
Habib, Giuseppe ULg; Kerschen, Gaëtan ULg

in Proceeding IMAC XXXIII A Conference and Exposition on Structural Dynamics, Orlando 2-5 February 2015 (2015, February 03)

The objective of the present study is to mitigate, or even completely eliminate, the limit cycle oscillations in mechanical systems using a passive nonlinear absorber, termed the nonlinear tuned vibration ... [more ▼]

The objective of the present study is to mitigate, or even completely eliminate, the limit cycle oscillations in mechanical systems using a passive nonlinear absorber, termed the nonlinear tuned vibration absorber (NLTVA). An unconventional aspect of the NLTVA is that the mathematical form of its restoring force is not imposed a priori, as it is the case for most existing nonlinear absorbers. The NLTVA parameters are determined analytically using stability and bifurcation analyses, and the resulting design is validated numerically using the MATCONT software. The proposed developments are illustrated using a Van der Pol-Du ng primary system. [less ▲]

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See detailPrésentation de cas cliniques résolus ou non résolus
WANG, François-Charles ULg

Scientific conference (2015, February 03)

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See detailEstimation of the Time Interval between the Administration of Heroin and the Sampling of Blood in Chronic Inhalers
DUBOIS, Nathalie ULg; HALLET, Claude ULg; SEIDEL, Laurence ULg et al

in Journal of Analytical Toxicology (2015)

To develop a model for estimating the time delay between last heroin consumption and blood sampling in chronic drug users. Eleven patients, all heroin inhalers undergoing detoxification, were included in ... [more ▼]

To develop a model for estimating the time delay between last heroin consumption and blood sampling in chronic drug users. Eleven patients, all heroin inhalers undergoing detoxification, were included in the study. Several plasma samples were collected during the detoxification procedure and analyzed for the heroin metabolites 6-acetylmorphine (6AM), morphine (MOR), morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G), according to a UHPLC/MSMS method. The general linear mixed model was applied to time-related concentrations and a pragmatic four-step delay estimation approach was proposed based on the simultaneous presence of metabolites in plasma. Validation of the model was carried out using the jackknife technique on the 11 patients, and on a group of 7 test patients. Quadratic equations were derived for all metabolites except 6AM. The interval delay estimation was 2–4 days when only M3G present in plasma, 1–2 days when M6G and M3G were both present, 0–1 day when MOR, M6G and M3G were present and <2 h for all metabolites present. The ‘jackknife’ correlation between declared and actual estimated delays was 0.90. The overall precision of the delay estimates was 8–9 h. The delay between last heroin consumption and blood sampling in chronic drug users can be satisfactorily predicted from plasma heroin metabolites. [less ▲]

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