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See detailExperimental analysis of 2:1 modal interactions with noncommensurate linear frequencies in an aerospace structure
Noël, Jean-Philippe ULg; Renson, Ludovic ULg; Kerschen, Gaëtan ULg

in Proceedings of the 8th European Nonlinear Dynamics Conference (ENOC) (2014, July)

Nonlinear interactions between modes with noncommensurate linear frequencies are studied. It is experimentally evidenced that a strongly nonlinear, full-scale aerospace structure may exhibit such 2:1 ... [more ▼]

Nonlinear interactions between modes with noncommensurate linear frequencies are studied. It is experimentally evidenced that a strongly nonlinear, full-scale aerospace structure may exhibit such 2:1 interactions in typical testing conditions. The experimental observations are compared with numerical predictions. [less ▲]

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See detailNghiên cứu và thiết kế hai kiểu chuồng nuôi nhông cát Leiolepis guttata (Cuvier, 1829) phù hợp với điều kiện nuôi và vốn đầu tư tại huyện Bắc Bình, tỉnh Bình Thuận
Tran, Tinh ULg; Tran, Ngoc Nguyen Kim Dieu; Vo, Kim Thong et al

in Journal of Agriculture Sciences and Technology (2014), 1/2014

Building of an enclosure for rearing of the spotted butterfly lizard, Leiolepis guttata (Cuvier, 1829), by the first farmer in 2004 (in Hong Chinh commune, Hoa Thang ward, Bac Binh district, Binh Thuan ... [more ▼]

Building of an enclosure for rearing of the spotted butterfly lizard, Leiolepis guttata (Cuvier, 1829), by the first farmer in 2004 (in Hong Chinh commune, Hoa Thang ward, Bac Binh district, Binh Thuan province) is considered as a fortuitous discovery which was the initiator of the current expanding trend of its rearing. Because L. guttata is a wild animal, with strong disease resistance and adaptation capacity, livestock farmers are presently not very interested in important aspects: rearing techniques, enclosure’s types, sex ratio, diseases’ prevention, etc. Notably the building of enclosures not perfectly suitable breeds a noticeable loss of the number of lizards and a reduction in the profits for the farmers. To this end, the building of two types of enclosures adapted to local rearing conditions and the investing capital available in Bac Binh district, Binh Thuan province is presently essential. We descrite two types of enclosure: the first one surrounded by a bricks (or breeze blocks) wall, the second one fended by a fiber cement corrugated sheets wall. Moreover, we suggest to introduce plants in order to build a vegetal cover nearer to the natural environment of L. guttata: shrubs and a plant carpet becoming the preferential refuge area of the spotted butterfly lizard. [less ▲]

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See detailRecollection and familiarity in normal and pathological aging
Bastin, Christine ULg

Conference (2014, July)

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See detailBiological indicators of soil quality over landscape spatial scales: a case study in Southern Belgium
Krüger, Inken ULg; Chartin, Caroline; Van Wesemael, Bas et al

Poster (2014, July)

Biological indicators are organisms or biological processes whose values give quantitative information on the capacity of a soil to function. Their fast dynamic allows to detect changes on short ... [more ▼]

Biological indicators are organisms or biological processes whose values give quantitative information on the capacity of a soil to function. Their fast dynamic allows to detect changes on short timescales. Five biological indicators (basal respiration, nitrogen mineralisation, microbial carbon and nitrogen, earthworm abundance and biomass, functional microbial diversity) as well as two ecophysiological indices (microbial quotient and metabolic quotient) were tested for their power to characterize the biological soil quality on a landscape level at 60 sites in two South-Belgian landscape units were investigated. All biological indicators differed significantly between the two landscape units showing the biological indicators to be discriminatory on a landscape level. Within each landscape unit, no relationships between biological indicators were found, underlining the need to measure multiple biological indicators. The results represent the first data for a South-Belgian monitoring network of biological soil quality. [less ▲]

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See detailMcCune-Albright Syndrome: A Detailed Pathological And Genetic Analysis of Disease Effects in an Adult Patient.
Vasilev, Vladimir; Daly, Adrian ULg; THIRY, Albert ULg et al

in The Journal of clinical endocrinology and metabolism (2014)

Context: McCune Albright syndrome (MAS) is a clinical association of endocrine and non-endocrine anomalies caused by post-zygotic mutation of the GNAS1 gene, leading to somatic activation of the ... [more ▼]

Context: McCune Albright syndrome (MAS) is a clinical association of endocrine and non-endocrine anomalies caused by post-zygotic mutation of the GNAS1 gene, leading to somatic activation of the stimulatory alpha subunit of G protein (Gsalpha). Important advances have been made recently in describing pathological characteristics of many MAS-affected tissues, particularly pituitary, testicular and adrenal disease. Other rarer disease related features are emerging. Objective: To study pathological and genetic findings of MAS on a tissue-by-tissue basis in classically and non classically affected tissues. Design: A comprehensive autopsy and genetic analysis Setting: Tertiary referral University Hospital Patients: Adult male patient with MAS and severe disease burden including gigantism Intervention(s): Clinical, hormonal and radiographic studies; gross and microscopic pathology analyses, conventional PCR and droplet digital PCR analyses of affected and non affected tissues Main Outcome Measure: Pathological findings, presence of GNAS1 mutations Results: The patient was diagnosed with MAS syndrome at six years of age based on the association of cafe-au-lait spots and radiological signs of polyostotic fibrous dysplasia. Gigantism developed and hyperprolactinemia, hypogonadotropic hypogonadism and hyperparathyroidism were diagnosed throughout adult period. The patient died at the age of 39 from pulmonary embolism. A detailed study revealed mosaiscism for the p.R201C GNAS mutation distributed across many endocrine and non-endocrine tissues. These genetically implicated tissues included rare or previously undescribed disease associations including primary hyperparathyroidism, and hyperplasia of the thymus and endocrine pancreas. Conclusions: This comprehensive pathological study of a single patient highlights the complex clinical profile of MAS and illustrates important advances in understanding the characteristics of somatic GNAS1 related pathology across a wide range of affected organs. [less ▲]

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See detailMultiscale Computational Modeling of Deformation Mechanics andIntergranular Fracture in Nanocrystalline Copper
Péron-Lührs, Vincent ULg; Sansoz, Frédéric; Jérusalem, Antoine et al

in Computational Materials Science (2014), 90

The material description is based on two constitutive elements, the grains (or bulk crystals) and the grainboundaries (GBs), both having their behavior determined atomistically using the quasicontinuum ... [more ▼]

The material description is based on two constitutive elements, the grains (or bulk crystals) and the grainboundaries (GBs), both having their behavior determined atomistically using the quasicontinuum (QC) method by simulating the plastic deformation of [110] tilt crystalline interfaces undergoing simple shear, tension and nano-indentation. Unlike our previous work [V. Péron-Lührs et al., JMPS, 2013] however, the GB thickness is here calibrated in the model, providing more accurate insight into the GB widths according to the interface misorientation angle. In this contribution, the new two-scale model is also validated against fullyatomistic NC simulations tests for two low-angle and high-angle textures and two grain sizes. A simplified strategy aimed at predicting the mechanical behavior of more general textures without the need to run more QC simulations is also proposed, demonstrating significant reduction in computational cost compared to full atomistic simulations. Finally, by studying the response of dogbone samples made of NC copper, we show in this paper that such a two-scale model is able to quantitatively capture the differences in mechanical behavior of NC metals as a function of the texture and grain size, as well as to accurately predict the processes of inter-granular fracture for different GB character distributions. This two-scale method is found to be an effective alternative to other atomistic methods for the prediction of plasticity and fracture in NC materials with a substantial number of 2-D grains such as columnar-grained thin films for micro-scale electro-mechanical devices. [less ▲]

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See detailCROSSROADS
Sacré, Robert ULg

Diverse speeche and writing (2014)

Programme radio hebdomadaire (chaque mercredi 18h-20h) sur Equinoxe FM 100.1 streaming www.equinoxefm.be

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See detailInformations sur la Continuité Ecologique - ICE -Evaluer le franchissement des obstacles par les poissons. Principes et méthodes
Baudoin, Jean-Marc; Burgun, Vincent; Chanseau, Matthieu et al

Book published by Onema (2014)

La fragmentation des milieux naturels est l’une des principales causes d’érosion de la biodiversité. L’impact des obstacles à l’écoulement se manifeste par une dégradation des milieux aquatiques et ... [more ▼]

La fragmentation des milieux naturels est l’une des principales causes d’érosion de la biodiversité. L’impact des obstacles à l’écoulement se manifeste par une dégradation des milieux aquatiques et consécutivement des biocénoses et des processus écologiques qu’ils abritent. Face aux exigences réglementaires (directive cadre sur l’eau, loi sur l’eau et les milieux aquatiques, grenelle de l’environnement, règlement européen de sauvegarde de l’anguille…) et à l'ensemble des enjeux environnementaux de la restauration de la continuité écologique des milieux aquatiques, l’Onema a souhaité développer un “outil ” permettant de diagnostiquer et quantifier les éventuels impacts des ouvrages hydrauliques sur la libre circulation de l'ichtyofaune. Le protocole ICE est une méthodologie nationale de production d’ “Informations sur la Continuité Ecologique” à destination des acteurs de l'environnement et de l'aménagement du territoire, des scientifiques, des enseignants, bureaux d’études et tout public intéressé. Il s'appuie sur une importante synthèse des connaissances scientifiques internationales actuelles et sur les productions scientifiques et techniques d’un groupe de travail composé d'experts français (Onema et Ecogea) et belge (Université de Liège). L'objectif de ce document est de présenter les enjeux de la continuité piscicole, les principes scientifiques qui ont prévalu à la construction de cette méthodologie d’évaluation, ainsi que le protocole standardisé qui a été développé. Il permet de diagnostiquer de manière simple et objective le risque d'entrave au déplacement de l'ichtyofaune en montaison, généré par les principaux types d'obstacles physiques à l’écoulement et pour les espèces communes des cours d'eau de France métropolitaine. Ce diagnostic repose sur la confrontation des caractéristiques typologiques, géométriques et hydrauliques des obstacles avec les capacités physiques de déplacement des espèces de poissons considérées. [less ▲]

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See detailInverting Hydraulic Heads In An Alluvial Aquifer Constrained With Electrical Resistivity Tomography Data Through Multiple-Point Statistics And Probability Perturbation Method: A Case Study
Hermans, Thomas ULg; Scheidt, Celine; Caers, Jef et al

Conference (2014, July)

Solving spatial inverse problems in the Earth Sciences remains a considerable challenge given the large number of parameters to invert for, the non-linearity of forward models and as a result the ill ... [more ▼]

Solving spatial inverse problems in the Earth Sciences remains a considerable challenge given the large number of parameters to invert for, the non-linearity of forward models and as a result the ill-posedness of the problem. Geostatistics is therefore needed to specify prior models, more particularly, information to control the spatial features of the inverse solutions. We used multiple-point statistics (MPS) to build models of pre-defined hydrofacies: clay, sand and gravel facies constrained to geological data (hard data) and geophysical data (soft data). The electrical resistivity tomography method was chosen to bring relevant spatially distributed information on the presence of the facies, given its sensitivity to variations in lithology and porosity. The comparison of the geophysical signature of the deposits with direct observations in boreholes enables to derive the conditional probability of observing a facies given its electrical resistivity. This is used to produce probability maps for each facies and constrain stochastic simulations of the alluvial aquifer. Then, the probability perturbation method (PPM) is used to integrate hydraulic heads data, using MPS to generate models. This process enables us to obtain calibrated models of the aquifer. The PPM algorithm will automatically seek solutions fitting both hydrogeological data and training-image based geostatistical constraints. Only geometrical features of the model are affected by the perturbation, i.e. we do not attempt to directly find the optimal value of hydrogeological parameters (chosen a priori), but the optimal spatial distribution of facies whose prior distribution is quantified in a training image. The methodology is first tested with a synthetic benchmark. The tests performed show that the choice of the training image is a major source of uncertainty. Therefore, one first needs to select those training images consistent with the geophysical data (and hence reject the inconsistent ones). Then, we proceed with them to hydrogeological inversions. Geophysical data (soft constraints) acts as an accelerator of convergence by reducing prior uncertainty. The hydraulic conductivity of each facies is a sensitive parameter, but it can be easily optimized prior to the PPM process. The stochastic method is then successfully applied within the context of an alluvial aquifer submitted to a pumping experiment. We show how the integration of various sources of data (borehole logs, geophysics, hydraulic heads) aids in calibrating hydrogeological models, locating high hydraulic conductivity zones and reducing uncertainty. The developed methodology proposes a common framework (multiple-point statistics) to integrate various information sources with variable resolutions relevant for hydrogeology: geological, geophysical and hydrogeological data. The method can be extended to integrate tracer tests to enable the calibration of transport parameters as well. The originality of the method is to use geophysical data both to refine the choice of the training image and to constrain the inversion of hydrogeological models. [less ▲]

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See detailPhylogenetic placement, species delimitation, and cyanobiont identity of endangered aquatic Peltigera species (lichen-forming Ascomycota, Lecanoromycetes)
Miadlikowska, Jolanta; Richardson, David; Magain, Nicolas ULg et al

in American Journal of Botany (2014)

Premise of this study: Aquatic cyanolichens from the genus Peltigera section Hydrothyriae are subject to anthropogenic threats and, therefore, are considered endangered. In this study we addressed the ... [more ▼]

Premise of this study: Aquatic cyanolichens from the genus Peltigera section Hydrothyriae are subject to anthropogenic threats and, therefore, are considered endangered. In this study we addressed the phylogenetic placement of section Hydrothyriae within Peltigera. We delimited species within the section and identified their symbiotic cyanobacteria. • Methods: Species delimitation and population structure were explored using monophyly as a grouping criterion (RAxML) and Structurama based on three protein-coding genes in combination with two nuclear ribosomal loci. The 16S and rbcLX sequences for the cyanobionts were analyzed in the broad phylogenetic context of free-living and symbiotic cyanobacteria. • Key results: We confirm with high confidence the placement of section Hydrothyriae within the monophyletic genus Peltigera; however, its phylogenetic position within the genus remains unsettled. We recovered three distinct monophyletic groups corresponding to three species: P. hydrothyria, P. gowardii s.s., and P. aquatica Miadl. & Lendemer, the latter being formally introduced here. Each species was associated with an exclusive set of Nostoc haplotypes. • Conclusions: The ITS region alone provides sufficient genetic information to distinguish the three morphologically cryptic species within section Hydrothyriae. Section Hydrothyriae seems to be associated with a monophyletic lineage of Nostoc, that has not been found in symbiotic association with other members of Peltigera. Capsosira lowei should be transferred to the genus Nostoc. Potential threats to P. aquatica should be re-examined based on the recognition of two aquatic species in western North America. [less ▲]

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See detailThe development of a safety culture: a fanciful hope in the health care sector ?
COUCKE, Philippe ULg

in Belgian Journal of Medical Oncology [=BJMO] (2014), 8(3), 66-71

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See detailUn univers de perles - l'évolution des étoiles
Nazé, Yaël ULg

Article for general public (2014)

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See detailBeyond the limits of a deductive approach based on ideal types and configurations
Moreau, Charlotte ULg; Pichault, François ULg; Mertens de Wilmars, Sybille ULg

Conference (2014, July)

This paper presents an original theoretical model combining ideal-types and bundles in order to apprehend a poorly studied phenomenon, the professionalization of human resource management (HRM) in social ... [more ▼]

This paper presents an original theoretical model combining ideal-types and bundles in order to apprehend a poorly studied phenomenon, the professionalization of human resource management (HRM) in social enterprises. This theoretical model elaborated from a literature review fits into a deductive approach. The first objective of this contribution is to show the added values and limits of such an a priori conceptualization. By replacing that model within the contextualist framework of analysis (Pettigrew, 1987) and by equipping that approach with adapted methodologies, some limits inherent in a deductive approach are avoided. The second goal of this paper is then to demonstrate how such a combination helps to pass over the limits of the theoretical model based on bundles and ideal types. [less ▲]

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See detailMolecular detection of six high importance endosymbiotic bacteria in Belgian wild-caught mosquitoes
Raharimalala, Fara Nantenaina ULg; Boukraa, Slimane ULg; Bawin, Thomas ULg et al

Poster (2014, July)

Introduction Several disease vectors presented a resistance to various pesticides currently used. One of an alternative solution was to use endosymbiotic bacteria because their probably interactive ... [more ▼]

Introduction Several disease vectors presented a resistance to various pesticides currently used. One of an alternative solution was to use endosymbiotic bacteria because their probably interactive effects with their host. According to the introduction risks of mosquito born disease and their dispersion, we propose to investigate the prevalence of six endosymbiontic bacteria in wild-caught Culicidae in Belgium. Methods Eleven species of Belgian fields mosquitoes (Culex pipiens s.l., Cx. torrentium, Cx. hortensis, Anopheles claviger, An. maculipennis s.l., An. plumbeus, Culiseta annulata, Ochlerotatus geniculatus, Oc. dorsalis, Aedes albopictus and Coquillettidia richiardii) were used for the screening of six genera endosymbiotic bacteria (Wolbachia sp., Commamonas sp., Delftia sp., Pseudomonas sp., Acinetobacter sp. and Asaia sp.) according to their possible impact in mosquito biology. PCR was done for the screening and positives bands were sequenced and deposited in GenBank. Results Total of 144 larvae and 32 adults were used. Wolbachia, Pseudomonas, Acinetobacter and Asaia were found in mosquitoes with different proportions, according to stages (adults, larvae) with a predominance of Pseudomonas in all species, as far as Acinetobacter and Asaia also have a high prevalence. Commamonas and Delftia were absent from all species tested, either in larvae and in adults. Discussion Choice of endosymbiotic bacteria studied here was allowing of their importance in literature. For Pseudomonas, it showed that this bacteria could produced ovipositon attractants for mosquito. Acinetobacter was suggested efficient in transmission and maintenance within host populations. Asaia was capable of efficiently crossing body barriers and colonizing different organs. Wolbachia was currently the most studied bacteria which plays an important role in the genetic manipulation of the host. Present advances in understanding the mosquito–microbiota relationships may have a great impact in a better understanding of some traits of mosquito biology and in the development of innovative mosquito-borne disease-control strategies. [less ▲]

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See detailAtelier jeux vidéo, paroles d'amateurs
Hurel, Pierre-Yves ULg

Article for general public (2014)

"Dans le dernier numéro de C4, nous vous expliquions le défi que l'association s'était lancé à travers un nouvel atelier multimédia : rassembler une dizaine de personnes totalement néophytes en ... [more ▼]

"Dans le dernier numéro de C4, nous vous expliquions le défi que l'association s'était lancé à travers un nouvel atelier multimédia : rassembler une dizaine de personnes totalement néophytes en programmation pour créer un prototype de jeu vidéo. Son déroulement s'est construit à la croisée de la création assistée et du do it yourself, du serious game et du jeu traditionnel, de l'humour et de l'engagement politique. Douze séances de trois à quatre heures, une release party et une couverture de l'affaire par La Meuse plus tard, retour sur cette aventure à travers quelques citations entendues lors de l'atelier." [less ▲]

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See detailModeling the hygrothermal response of a prefabricated straw bale panel and assessing its impact on indoor climate
Dubois, Samuel ULg; Evrard, Arnaud; Lebeau, Frédéric ULg

in 2014 ASABE and CSBE/SCGAB Annual International Meeting (2014, July)

Crop-based materials show many qualities in the quest for construction products with low environmental impact in the construction sector. Their ability to exchange moisture with indoor air offers new ... [more ▼]

Crop-based materials show many qualities in the quest for construction products with low environmental impact in the construction sector. Their ability to exchange moisture with indoor air offers new opportunities for improving interior user comfort and eventually buildings energy performance. Modeling their hygrothermal behavior has thus focused much attention, one of the main objectives being to assess more objectively the resulting performance at building scale. The first natural step in this modeling process is to understand the specific dynamics of heat and mass transfer within such materials. The Building Element Heat Air and Moisture (BEHAM) numerical models were designed to accurately predict internal conditions encountered in materials with partial balance equations. This envelope-based approach, however, requires the knowing of the interior and exterior climate conditions prior to the study. Therefore, it forbids any assessment of mutual exchange between the envelope to the indoor air and prevents any serious validation of the overall performance of materials. In response to this problem, the importance of developing whole building hygrothermal model has recently been raised. General scientific computational tools like MATLAB seem particularly adapted to perform this scaling-up, given their high flexibility and tools integration potentialities. In this communication we study a prefabricated straw bale panel subjected to two distinct and simple solicitations in a climatic chamber. A whole building hygrothermal model developed in MATLAB is then validated with the experimental datasets. The evolution of indoor conditions under the different tests is analyzed in details with an assessment of straw bales performance. [less ▲]

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See detailPrecision Asteroseismology of the Pulsating White Dwarf GD 1212 Using a Two-wheel-controlled Kepler Spacecraft
Hermes, J.J.; Charpinet, Stéphane; Barclay, Thomas et al

in Astrophysical Journal (2014), 789

We present a preliminary analysis of the cool pulsating white dwarf (WD) GD 1212, enabled by more than 11.5 days of space-based photometry obtained during an engineering test of the two-reaction-wheel ... [more ▼]

We present a preliminary analysis of the cool pulsating white dwarf (WD) GD 1212, enabled by more than 11.5 days of space-based photometry obtained during an engineering test of the two-reaction-wheel-controlled Kepler spacecraft. We detect at least 19 independent pulsation modes, ranging from 828.2-1220.8 s, and at least 17 nonlinear combination frequencies of those independent pulsations. Our longest uninterrupted light curve, 9.0 days in length, evidences coherent difference frequencies at periods inaccessible from the ground, up to 14.5 hr, the longest-period signals ever detected in a pulsating WD. These results mark some of the first science to come from a two-wheel-controlled Kepler spacecraft, proving the capability for unprecedented discoveries afforded by extending Kepler observations to the ecliptic. [less ▲]

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See detailQuel système d'évaluations génétiques pour les verrats Piétrain en Wallonie
Dufrasne, Marie ULg; Piedboeuf, Maureen; Wavreille, José et al

Article for general public (2014)

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