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See detailPaleogenetic study of ancient DNA suggestive of X-Linked acrogigantism
Beckers, Albert ULg; Fernandes, Daniel; Fina, Frederic et al

in Endocrine-Related Cancer (2017)

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See detailHot-Melt Extrusion as a Continuous Manufacturing Process to Form Ternary Cyclodextrin Inclusion Complexes
Thiry, Justine ULg; Krier, Fabrice; Ratwatte, Shenelka et al

in European Journal of Pharmaceutical Sciences (2017), 96

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See detailDiscovery of a low-mass companion inside the debris ring surrounding the F5V star HD 206893
Milli, J.; Hibon, P.; Christiaens, Valentin ULg et al

in Astronomy and Astrophysics (2017), 597

<BR /> Aims: Uncovering the ingredients and the architecture of planetary systems is a very active field of research that has fuelled many new theories on giant planet formation, migration, composition ... [more ▼]

<BR /> Aims: Uncovering the ingredients and the architecture of planetary systems is a very active field of research that has fuelled many new theories on giant planet formation, migration, composition, and interaction with the circumstellar environment. We aim at discovering and studying new such systems, to further expand our knowledge of how low-mass companions form and evolve. <BR /> Methods: We obtained high-contrast H-band images of the circumstellar environment of the F5V star HD 206893, known to host a debris disc never detected in scattered light. These observations are part of the SPHERE High Angular Resolution Debris Disc Survey (SHARDDS) using the InfraRed Dual-band Imager and Spectrograph (IRDIS) installed on VLT/SPHERE. <BR /> Results: We report the detection of a source with a contrast of 3.6 × 10[SUP]-5[/SUP] in the H-band, orbiting at a projected separation of 270 milliarcsec or 10 au, corresponding to a mass in the range 24 to 73 M[SUB]Jup[/SUB] for an age of the system in the range 0.2 to 2 Gyr. The detection was confirmed ten months later with VLT/NaCo, ruling out a background object with no proper motion. A faint extended emission compatible with the disc scattered light signal is also observed. <BR /> Conclusions: The detection of a low-mass companion inside a massive debris disc makes this system an analog of other young planetary systems such as β Pictoris, HR 8799 or HD 95086 and requires now further characterisation of both components to understand their interactions. [less ▲]

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See detailThe EACVI Echo Handbook.
Nchimi Longang, Alain ULg

in European Heart Journal (2017)

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See detailIdentification of complex nonlinearities using cubic splines with automatic discretization
Dossogne, Tilàn ULg; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

in Proceedings of the International Modal Analysis Conference (IMAC) XXXV (2017, January)

One of the major challenges in nonlinear system identification is the selection of appropriate mathematical functions to model the observed nonlinearities. In this context, piecewise polynomials, or ... [more ▼]

One of the major challenges in nonlinear system identification is the selection of appropriate mathematical functions to model the observed nonlinearities. In this context, piecewise polynomials, or splines, offer a simple and flexible representation basis requiring limited prior knowledge. The generally-adopted discretization for splines consists in an even distribution of their control points, termed knots. While this may prove successful for simple nonlinearities, a more advanced strategy is needed for nonlinear restoring forces with strong local variations. The present paper specifically introduces a two-step methodology to select automatically the location of the knots. It proposes to derive an initial model, using nonlinear subspace identification, and incorporating cubic spline basis functions with fixed and equally-spaced abscissas. In a second step, the location of the knots is optimized iteratively by minimizing a least-squares cost function. A single-degree-of-freedom system with a discontinuous stiffness characteristic is considered as a case study. [less ▲]

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See detailAttack-Prevention and Damage-Control Investments in Cybersecurity
Lam, Wing Man Wynne ULg

Scientific conference (2017, January)

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See detailExperimental Assessment of the Influence of Interface Geometries on Structural Dynamic Response
Dossogne, Tilàn ULg; Jerome, Trevor; Lancereau, Damien et al

in Proceedings of the International Modal Analysis Conference (IMAC) XXXV (2017, January)

Jointed interfaces are sources of the greatest amount of uncertainty in the dynamics of a structural assembly. In practice, jointed connections introduce nonlinearity into a system, which is often ... [more ▼]

Jointed interfaces are sources of the greatest amount of uncertainty in the dynamics of a structural assembly. In practice, jointed connections introduce nonlinearity into a system, which is often manifested as a softening response in frequency response, exhibiting amplitude dependent damping and stiffness. Additionally, standard joints are highly susceptible to unrepeatability and variability that make meaningful prediction of the performance of a system prohibitively difficult. This high degree of uncertainty in joint structure predictions is partly due to the physical design of the interface. This paper experimentally assesses the influence of the interface geometry on both the nonlinear and uncertain aspects of jointed connections. The considered structure is the Brake-Reuß beam, which possesses a lap joint with three bolted connections, and can exhibit several different interface configurations. Five configurations with different contact areas are tested, identified, and compared, namely joints with complete contact in the interface, contact only under the pressure cones, contact under an area twice that of the pressure cones, contact only away from the pressure cones and Hertzian contact. The contact only under the pressure cone and Hertzian contact are found to behave linearly in the range of excitation used in this work. The contact area twice that of the pressure cone behaves between the complete contact and contact only under the pressure cone cases. [less ▲]

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See detailTHE LACTOPEROXIDASE SYSTEM, A NATURAL BIOCHEMICAL BIOCONTROL AGENT FOR PRE- AND POST-HARVEST APPLICATIONS
Bafort, Françoise ULg; Parisi, Olivier ULg; Perraudin, Jean-Paul et al

in Journal of Phytopathology (2017), 165(1), 22-34

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See detailLooking for phosphate-accumulating bacteria in activated sludge processes : a multidisciplinary approach
Tarayre, Cédric ULg; Charlier, Raphaëlle; Delepierre, Anissa ULg et al

in Environmental Science and Pollution Research (2017)

Over the past decades, an increasing need in renewable resources has progressively appeared. This trend concerns not only fossil fuels but also mineral resources. Wastewater and sewage sludge contain ... [more ▼]

Over the past decades, an increasing need in renewable resources has progressively appeared. This trend concerns not only fossil fuels but also mineral resources. Wastewater and sewage sludge contain significant concentrations in phosphate and can be considered as a fertilizer source of the utmost importance. In wastewater treatment plants, the biological uptake of phosphate is performed by a specific microbiota: the phosphate-accumulating organisms. These microorganisms are recovered in sewage sludge. Here, we aimed to investigate the occurrence of phosphate accumulators in four wastewater treatment plants. A 16S metagenetic analysis identified the main bacterial phyla extracted from the aerobic treatment: α-Proteobacteria, β-Proteobacteria, and Sphingobacteria. An enrichment stage was performed to stimulate the specific growth of phosphate-accumulating bacteria in an acetate medium. An analysis of metabolic activities of sulfur and phosphorus highlighted strong modifications related to phosphorus and much less distinguishable effects with sulfur. A solid acetate medium containing 5-Br-4-Cl-3-indolyl phosphate was used to select potential phosphate-accumulating bacteria from the enriched consortia. The positive strains have been found to belong in the genera Acinetobacter, Corynebacterium, and Pseudomonas. Finally, electron microscopy was applied to the strains and allowed to confirm the presence of polyphosphate granules. Some of these bacteria contained granules the size of which exceeded 100 nm. [less ▲]

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See detailImpact of food type on respiration, fractionation and turnover of carbon and nitrogen stable isotopes in the marine amphipod Gammarus aequicauda (Martynov, 1931).
Remy, François ULg; Darchambeau, François ULg; Melchior, Aurélie et al

in Journal of Experimental Marine Biology & Ecology (2017), 486

This study experimentally determined the impact of food source type on turnover rate and trophic enrichment factors (TEFs or ∆) of δ13C and δ15N, as well as on respiration rate, in captive populations of ... [more ▼]

This study experimentally determined the impact of food source type on turnover rate and trophic enrichment factors (TEFs or ∆) of δ13C and δ15N, as well as on respiration rate, in captive populations of the marine amphipod Gammarus aequicauda. Gammarus aequicauda (318 individuals) were fed ad libitum with three food sources animal, algae, and dead Posidonia oceanica leaves (also called “litter”), varying in palatability, digestibility, nutritional qualities and isotopic compositions, for between four and six weeks in a controlled feeding experiment. The resulting death rate was lower for the amphipods fed with animal treatment (30.9%) than for individuals fed with algal (65.9%) or litter treatment (64.4%), indicating a better fitness of the individuals fed with the animal food source. Respiration rates also differed highly among the treatments. Animal treatment showed higher respiration rates than algal and litter treatments, potentially due to the toxicity of the algae and the very low nutritional quality of the litter. Amphipods fed with these treatments might have entered in a “low activity state” to cope with these unsuitable food sources, inducing low respiration rates. Due to the very low assimilation and toxicity of the algae source, turnover rate for δ13C was impossible to determine. Turnover rate for δ13C was much faster (half-life = 12.55 days) for amphipods fed with the animal food source than for amphipods fed with litter (half-life = 51.62 days), showing the faster assimilation of the most nutritionally optimal food sources by G. aequicauda. Turnover for δ15N was impossible to determine because the amphipods were already at isotopic equilibrium at the beginning of the experiment. Despite the detritus feeder status of Gammarus aequicauda, TEFs for the animal treatments were in accordance with values generally found for carnivorous organisms (∆13C = 0.9 ± 0.7‰; ∆15N = 2.9 ± 0.6‰). TEFs for the litter treatment were in accordance with values generally corresponding to detritivorous organisms (∆13C = 1.2‰; ∆15N = 1.0 ± 0.4‰). SIAR mixing model outputs obtained with these new TEF values were more constrained and coherent than outputs obtained with general literature TEFs. This study thus demonstrated the non-negligible impact of the food source on Gammarus aequicauda physiological status, fitness and turnover rates, but also on TEFs—highlighting the importance of TEF experimental calculations for every potential food source of a given organism to ensure more robust isotopic data interpretation. [less ▲]

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See detailMethane balance of an intensively grazed pasture and estimation of the enteric methane emissions from cattle
Dumortier, Pierre ULg; Aubinet, Marc ULg; Beckers, Yves ULg et al

in Agricultural and Forest Meteorology (2017), 232

The methane turbulent fluxes of an intensively grazed pasture were measured continuously from June 2012 to December 2013 at the Dorinne Terrestrial Observatory (DTO) in Belgium. During grazing periods ... [more ▼]

The methane turbulent fluxes of an intensively grazed pasture were measured continuously from June 2012 to December 2013 at the Dorinne Terrestrial Observatory (DTO) in Belgium. During grazing periods, the fluxes were dominated by enteric fermentation and were found to be strongly related to cow stocking density. In 2013, total emission from the pasture was found between 9 and 11 g CH4 m−2, 97% of which being emitted during grazing periods. Emission per LU (livestock unit) was estimated in a non-invasive way by integrating eddy covariance fluxes over large periods and by assuming a homogeneous average cattle disposition on the pasture. This estimate was compared to the one obtained during confinement periods, where cows were confined in a small part of the pasture. The emission per LU varied between 104 and 134 g CH4 LU−1 day−1 (13 and 17 g CH4 kg DMI−1), depending on the dataset and the computation method used. Diel course was characterized by two emission peaks, one in the morning and a larger one in the afternoon. For rest periods (no cattle on the pasture), small emissions were observed (median and mean values of 0.5 and 1.5 mg CH4 m−2 day−1, respectively). [less ▲]

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See detailThermal history modelling to understand microstructures observed in repair technology of Ti-6Al-4V
Tran, Hoang Son ULg; Tchuindjang, Jérôme Tchoufack ULg; Hakan, Paydas et al

in Extended Abstract book of 14th Conf. on Computer Methods in Materials Technology KomPlasTech 2017 (2017, January)

Laser cladding is a metal deposition technique used to fabricate or repair components. In the present work Ti-6Al-4V deposits with a variable thickness are studied to assess the use of laser cladding as a ... [more ▼]

Laser cladding is a metal deposition technique used to fabricate or repair components. In the present work Ti-6Al-4V deposits with a variable thickness are studied to assess the use of laser cladding as a repair technology [1]. Solidification following melting and partial remelting of pre-existing layers is coupled with heat treatment of the solidified material due to the repeated heating and cooling cycles during building. The effect of the building strategy on the metallurgical characteristics of the material for a decreasing track length (DTL) or a constant track length (CTL) strategy is analyzed. Depending on the possible heat accumulation, the nature of the phases are determined by metallography and hardness maps of the deposits. Optical Microscopy (OM), Stereo Microscopy (SM), and Scanning Electron Microscopy (SEM) were used in order to study the microstructure. The generation of the microstructure results from the material thermal history. This one is computed by Finite Element Method and a careful analysis establishes the link between the phase state and the detailed thermal history. [less ▲]

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See detailQuelques idées générales à propos de la compréhension en mathématiques
Bair, Jacques ULg

E-print/Working paper (2017)

Dans cet article, nous apportons des éléments de réponse à la question générale suivante : "Que signifie bien comprendre en mathématiques ?" Nous nous demandons pourquoi il est difficile d'y répondre et ... [more ▼]

Dans cet article, nous apportons des éléments de réponse à la question générale suivante : "Que signifie bien comprendre en mathématiques ?" Nous nous demandons pourquoi il est difficile d'y répondre et apportons une piste de solution en distinguant les activités de production de celles de reproduction. De plus, nous abordons le problème étudié d'un point de vue aussi bien local que global. Enfin, nous nous interrogeons sur l'incompréhension en mathématiques en proposant une typologie, en repérant des causes possibles d'incompréhension et en donnant quelques conseils pratiques. [less ▲]

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See detailRelevance of vitamin D in the pathogenesis and therapy of frailty.
Bruyère, Olivier ULg; Cavalier, Etienne ULg; Buckinx, Fanny ULg et al

in Current Opinion in Clinical Nutrition & Metabolic Care (2017), 20(1), 26-29

PURPOSE OF REVIEW: This article reviews recently published evidence regarding the role of vitamin D in the physiopathology of physical frailty in elderly populations and its role in the management of this ... [more ▼]

PURPOSE OF REVIEW: This article reviews recently published evidence regarding the role of vitamin D in the physiopathology of physical frailty in elderly populations and its role in the management of this geriatric condition. RECENT FINDINGS: Some recent studies have found a low level of 25-hydroxyvitamin D, considered the best marker of vitamin D status, in frail individuals. All prospective studies consistently report that low vitamin D status is associated with an increased risk of becoming frail. Recent studies also suggest that the relationship between vitamin D status and frailty is largely mediated by the development of sarcopenia. Very few well designed randomized controlled trials are available that assess the effectiveness of vitamin D supplementation in the prevention or management of frailty. In the absence of specific guidelines, a minimal serum 25-hydroxyvitamin D level of 75 nmol/l is proposed for frail elderly patients by some scientific societies. The doses necessary to reach this target are between 800 and 2000 IU/day. SUMMARY: Several studies suggest a potential effect of vitamin D on physical frailty but large clinical trials are lacking at this time to provide solid evidence of clinical benefit. [less ▲]

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See detailUn « Laboratoire belge » du droit international (1869-1940) ? Réseaux internationaux, expériences et mémoires de guerre des juristes belges
Genin, Vincent ULg

Doctoral thesis (2017)

Circonscrire une problématique implique de dégager plusieurs hypothèses de travail. La Première Guerre mondiale représente le pivot autour duquel ces hypothèses s’articuleront et seront mises à l’épreuve ... [more ▼]

Circonscrire une problématique implique de dégager plusieurs hypothèses de travail. La Première Guerre mondiale représente le pivot autour duquel ces hypothèses s’articuleront et seront mises à l’épreuve. Celle-ci étant destinée à les « mettre à l’épreuve ». À l’issue de ce travail, nous espérons que la confrontation de ces hypothèses à l’analyse historique permettra la décantation de conclusions générales dont émanera une thèse définie. La Guerre de 1914-1918, par son caractère global, ses « innovations » technologiques, son degré de violence, marque une étape significative de l’histoire contemporaine. La Belgique, premier pays du front Ouest à être envahi, se situe aux premières loges de cette nouvelle phase historique. Territoire dont la neutralité « perpétuelle, permanente et garantie » est violée, en transgression du droit international public, ce point d’ancrage semble propice à l’étude d’un milieu ayant peu attiré l’attention des historiens : les juristes belges de droit international. Nous estimons que cette étude est à même de mieux nous informer sur les caractéristiques de ce milieu professionnel en soi, concerné au premier chef par l’acte inaugural de la guerre, sur ses pratiques, ses codes, ses réseaux internationaux, la positionnalité des juristes, mais aussi, en négatif, de nous renseigner sur un aspect méconnu de l’image de la Belgique et de sa position dans la hiérarchie internationale, à savoir sa contribution au droit international. L’évolution de ce milieu et de ce qu’il représente, à l’aune de la Guerre de 1914-1918, reconnue pour avoir acceléré la juridicisation des relations internationales, constitue l’essentiel de l’angle d’approche adopté par notre recherche. Toutefois, il est permis de dégager plusieurs hypothèses, dont chacune recouvre un critère de cette approche plus générale : En effet, le conflit modifie-t-il le degré de légitimité de cette catégorie de juristes dans le champ scientifique belge et exerce-t-il une influence similaire dans le champ académique ? Dans quelle mesure les internationalistes belges jouent-ils un nouveau rôle, après 1918, dans le cadre de la politique étrangère officielle du pays ? Par extension, nous nous intéresserons à leur rapport au milieu des diplomates. Nous tenterons également d’évaluer dans quelle mesure ces juristes sont les acteurs d’un phénomène transnational ou, au contraire, s’ils poursuivent des objectifs dont les intérêts sont « nationaux ». Par ailleurs, ces juristes peuvent-ils être considérés comme des indicateurs, des pierres de touche, de l’évolution de la position de la Belgique dans le « Concert des nations » ? Le cas échéant, nous tenterons de comprendre dans quelle mesure cette « condition » d’indicateur évolue entre l’avant-1914 et l’après-1918. Ces juristes contribuent-ils à la défense d’enjeux idéologiques et/ou politiques et comment se positionnent-ils par rapport aux conceptions jusnaturalistes et juspositivistes ? À l’aune des réflexions précédentes, il est possible d’envisager une problématique générale, que l’on peut énoncer comme suit : Dans quelle mesure les juristes belges de droit international public, de la fin du XIXème siècle au milieu du XXème siècle, ont tissé des réseaux internationaux, été des indicateurs de l’évolution de la Belgique dans la hiérarchie internationale et, surtout, ont été influencés par l’expérience de la Guerre de 1914-1918, en tant que génératrice d’une mémoire influant sur les modes d’expressions et de représentations de ce groupe social, jusqu’en 1940. [less ▲]

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