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See detailIsolation and identification of anthropogenic particles in fish stomachs by Raman spectroscopy: a new method
Collard, France ULg; Gilbert, Bernard ULg; Eppe, Gauthier ULg et al

in Organohalogen Compounds (2015, August)

Microplastic particles (MP) contaminate oceans and affect marine organisms in several ways. Ingestion combined with food intake is generally reported. However, data interpretation is often circumvented by ... [more ▼]

Microplastic particles (MP) contaminate oceans and affect marine organisms in several ways. Ingestion combined with food intake is generally reported. However, data interpretation is often circumvented by the difficulty to separate MP from bulk samples. Visual examination is often used as one or the only step to sort these particles. However, color, size and shape are insufficient and often unreliable criteria. Here we present an isolation method of MP specially adapted to a subsequent analysis by Raman spectroscopy. This method avoids fluorescence problems allowing the identification anthropogenic particles (AP) from stomach contents of fish by Raman spectroscopy. It was validated with commercial samples of microplastics and cotton along with stomach contents from three different Clupeiformes fishes: Clupea harengus, Sardina pilchardus and Engraulis encrasicolus. The optimized digestion and isolation protocol showed no visible impact on microplastics and cotton particles while the spectroscopic analysis allowed precise identification of microplastics and textile fibers. This approach allowed us to isolate 35 particles. These were analyzed by Raman spectroscopy: eleven were microplastics and thirteen were made of cellulose or lignin, or both (mostly fibers). Some particles were not identified but contained artificial colorants. This isolation protocol will help to assess the presence, quantity and composition of AP in planktivorous fish stomachs. [less ▲]

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See detailThe effects of triclosan exposure in shape changes of sheepshead minnow (Cyprinodon variegatus) during early development and metamorphosis
Schnitzler, Joseph ULg; Frederich, Bruno ULg; Dussenne, Mélanie et al

Conference (2015, August)

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation ... [more ▼]

Thyroid hormones are essential for normal development, and for maintenance of normal physiological functions in vertebrates [1, 2]. In fish, thyroid hormones are involved in the control of osmoregulation, metabolism, somatic growth and post-hatching metamorphosis [1, 3, 4]. The regulation of thyroid hormone bioavailability in tissues and cells represents a very complex and unique web of feedback systems [2]. In fish and other vertebrates the thyroid cascade involves two components. First, thyroxine (T4) biosynthesis and secretion are largely under central control by the brain–pituitary–thyroid axis [5]. Second, there is the conversion of T4 to its biologically active form 3,5,3-triiodothyronine (T3) and its metabolism and receptor-mediated actions that seems largely to be under peripheral control in extra-thyroidal tissues [6]. The accumulation in the aquatic environment of anthropogenic chemicals, among which are endocrine disrupting chemicals (EDCs) that alter normal hormonal regulation, is having dramatic consequences for humans and wildlife. Numerous chemicals disrupt thyroid homeostasis affecting thyroid hormone (TH) synthesis and transport, and cellular uptake and metabolism [7, 8]. Triclosan (TCS) is a synthetic chlorinated phenolic compound with a generalized use as an antimicrobial and preservative in many personal care and household products [9-11]. As a result of disposal of TCS through sewage systems and insufficient/variable removal by wastewater treatment plants (WWTP) [9], widespread contamination with TCS has been detected in several countries, particularly in aquatic ecosystems, WWTP influents and effluents; sludges and biosolids; surface or ground water; drinking water; and aquatic sediments [9-11]. TCS and its metabolites have been detected in tissues and body fluids of aquatic organisms including fish, revealing they are accumulating in the food chain [9-11] and TCS has also been detected in human blood, breast milk and urine [9-11]. The structural similarity of TCS with THs [9] suggest it may have adverse effects on the thyroid system. However, little is known about the mechanisms by which TCS disrupts the thyroid axis. TCS effects on fish thyroid axis have not been investigated. It is possible, that the TCS toxic effects reported in fish embryos, larvae and adults [9-11] might be caused, at least in part, through its effect on the thyroid system. We determined how TCS affect ontogenic variations of thyroid hormones in developing sheepshead minnow larvae. Knowing that thyroid hormones are involved in somatic growth and post-hatching metamorphosis, we also tested the hypothesis that TCS alter the development of these larvae. To do this, we used landmark-based geometric morphometric methods. These methods allowed us to analyse the pure shape variations of our developing larvae, regardless orientation, position, and size. [less ▲]

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See detailSedimentological and geochemical evidence to detect arid periods recorded in wadi deposits: a case study from northern Morocco
El Ouahabi, Meriam ULg; Bartz, Melanie; Rixhon, Gilles et al

Poster (2015, July 27)

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See detailIdentification of VZV ORF9p potential cellular partners that could be important for the viral egress.
Lebrun, Marielle ULg; riva, laura; Rambout, Xavier ULg et al

Poster (2015, July 26)

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate ... [more ▼]

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate of the viral kinase ORF47p and that its ORF47p-dependent phosphorylation is important for the secondary envelopment process. We also have identified an acidic cluster (AC) within the protein that is important for its correct localization in the infected cells and for the interaction with ORF47p. The recombinant VZV expressing ORF9p-ΔAC presents an accumulation of capsids in the perinuclear space. ORF9p seems then to play an important role in several steps of the egress process. In this context, we sought to identify cellular partners of ORF9p that might be important for these functions. We performed a yeast two hybrid screen against the human ORFeome 5.1. and picked out 44 candidates among which 5 proteins playing roles in membrane organization and targeting. We currently are trying to confirm these interactions in infected cells and to assess the role of these interactions for the viral lytic cycle. [less ▲]

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See detailImpact of phenotypic heterogeneity and metabolic specialisation on metabolic engineering strategies: case of study of E.coli as a representative microbial cell factory
Brognaux, Alison ULg; Delepierre, Anissa ULg; Pecheux, Hélène ULg et al

Conference (2015, July 21)

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant ... [more ▼]

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant protein and pDNA production in bioprocesses. This phenotypic heterogeneity, first due to the noise, is reinforced by environmental heterogeneities occurring at large scale during fed-batch processes. This phenotypic heterogeneity has been tracked according to GFP reporter strains (biosensors) that circulate in the bioreactor and encounter environmental heterogeneities. First, we have highlighted the simultaneous occurrence of several phenotypes with distinct metabolic functions. Indeed, a diversity of glucose uptake strategies has recently been noticed with the PtsG and MglABC transporters. Moreover, when E.coli encounters zones of glucose excess, acetate is produced through the overflow metabolism. Only the sub-population with high acs expression (acetate transporter) could consume this acetate. GFP reporter strains have thus been constructed for PtsG, MgIABC and acs genes. In addition of the stable GFP, two destabilized GFP variants for each gene have been used to obtain more instantaneous responses. The response of these biosensors have been followed by on-line flow cytometry. In the end, this experimental strategy for direct phenotyping at the single cell level will also be used to investigate the impact of metabolic engineering strategies on phenotypic heterogeneity, robustness and fitness of microbial population in industrial conditions. [less ▲]

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See detailExploratory study of narratives in children with attention deficit hyperactivity disorder
Boulard, Aurore ULg; Pignatiello, Laure ULg; Leclercq, Cédric

Poster (2015, July 21)

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See detailA viscoelastic-viscoplastic-damage constitutive model based on a large strain hyperelastic formulation for amorphous glassy polymers
Nguyen, Van Dung ULg; Morelle, Xavier; Lani, Frédéric et al

in proceedings of the 20th International Conference on Composite Materials, Copenhagen, Denmark, 19-24th July 2015 (2015, July 20)

The aim of this work is to develop an efficient large-strain hyperelastic constitutive model for amorphous polymers in the glassy state. These materials exhibit a complex rate- and pressure-sensible ... [more ▼]

The aim of this work is to develop an efficient large-strain hyperelastic constitutive model for amorphous polymers in the glassy state. These materials exhibit a complex rate- and pressure-sensible behavior in both elastic and plastic regimes. After an initial linear elastic region, a nonlinear stage continues until reaching a peak stress, which is followed by a softening stage. At large strains, when the softening is saturated, a re-hardening stage is reached. The viscoelastic effect is captured using the generalized Maxwell model. The viscoplastic effect is considered using a Perzyna-type flow rule incorporating a pressure sensitive yield surface and a non-associated flow potential. This yield surface is extended from the Drucker-Prager one. The saturated softening phenomenon is modelled using an isotropic numerical damage variable progressed by a saturated softening law. With the introduction of the damage parameter, a non-local implicit gradient damage model is used to avoid the loss of the solution uniqueness. Through experimental comparisons, it is shown that the proposed model has the ability to model the complex mechanical responses of amorphous glassy polymers. [less ▲]

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See detailFunctionality of microbial phenotypic heterogeneity in bioprocessing conditions: an analysis based on the use of on-line flow cytometry
Delepierre, Anissa ULg

Conference (2015, July 20)

Microbial phenotypic heterogeneity is known to be naturally present in isogenic population and can be attributed to the stochastic nature of the biochemical reactions. An important question at this level ... [more ▼]

Microbial phenotypic heterogeneity is known to be naturally present in isogenic population and can be attributed to the stochastic nature of the biochemical reactions. An important question at this level was to determine whether such stochastic behavior exhibits some functionality, i.e. how single cell heterogeneity leads to population level strategies. One of this strategies, called bet-hedging, is known to give a competitive advantage to the population, by leading for example to a persistent phenotype able to survive to antibiotics exposure. Among the single cell toolbox available for the analysis of phenotypic heterogeneity, flow cytometry present the advantage of being compatible with bioprocess cultivation tools. In this work, we present an on-line analytical workflow based on automated flow cytometry that can be used to monitor simultaneously several bioreactors, testing different bioreactor operating conditions, in combination with fluorescent transcriptional reporter strategies: promoter involved in metabolism fused to a gene expressing an unstable variant of GFP , and viability fluorescent tagging: propidium iodide uptake, correlated with membrane permeability. [less ▲]

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See detailCombining mindfulness and ACT to learn how to manage emotions and to engage in valued activities: Assessment of the feasibility of a training group and its efficiency
Wagener, Aurélie ULg; Dierickx, Christophe; Blairy, Sylvie ULg

Poster (2015, July 18)

BACKGROUND Managing painful emotions could be an issue for a lot of adults. Indeed, learning how to manage painful emotions is an often-requested demand in psychotherapy. Mindfulness-based programs and ... [more ▼]

BACKGROUND Managing painful emotions could be an issue for a lot of adults. Indeed, learning how to manage painful emotions is an often-requested demand in psychotherapy. Mindfulness-based programs and acceptance and commitment therapy (ACT) offer useful tools which aim to guide in this learning process. ACT also provide guidelines to engage in valued activities. In order to help community adults to manage their painful emotions and to engage themselves in valued activities, we offer training group cycles combining tools of mindfulness-based programs and ACT. This study aims to assess the feasibility of such training groups and their efficiency. METHODS A longitudinal design with three assessment-times (T0, T1 and T2) is employed. Participants to the training group attend to three three-hours training sessions on a six-weeks period. They are assessed before the training sessions (T0), directly after (T1) and at three-months follow-up (T2). Questionnaires assess these variables: sociodemographic data, mood, mindfulness, psychological flexibility, cognitive coping strategies and behavioural activation. Student t tests for paired samples are conducted. RESULTS Fifty-four adults participated to four training cycles (the cycles are all identical). Until now, 28 participants (21 women) completed the T0 and the T1 (mean age = 41.43, SD = 11.83). Student t test indicate a significant decrease of depression (t(25) = 4.53, p < 0,001), anxiety (t(25) = 6.23, p < 0.001) and non-adaptive cognitive coping strategies (t(24) = 3.76, p < 0.001). Student t test also indicate a significant increase in mindfulness (t(26) = -3.87, p < 0.001), psychological flexibility (t(26)) = -5.48, p < 0.001) and behavioural activation (t(26) = -4.86, p < 0.001). DISCUSSION Preliminary results indicate the feasibility of training groups combining tools of mindfulness-based programs and ACT. Results show a decrease in several variables (depression, anxiety and non-adaptive cognitive coping strategies) and an increase in other variables (mindfulness, psychological flexibility and behavioural activation). These results seem to indicate that participants benefit from the training groups. Data collection is still ongoing and a control group (waiting-list) is currently being composed. Results and clinical implications will be further discussed during the congress. [less ▲]

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See detailTowards an "African Stylistics": Apprehending Cross-Cultural Creativity in the Works of Chris Abani
Tunca, Daria ULg

Conference (2015, July 18)

Anglophone African literatures have often been praised for their linguistic originality. More often than not, critics interested in the stylistic inventiveness of works from the continent have focused ... [more ▼]

Anglophone African literatures have often been praised for their linguistic originality. More often than not, critics interested in the stylistic inventiveness of works from the continent have focused their attention on these texts’ specifically “African” features, from the use of proverbs to the presence of words from indigenous languages. While these scholarly studies have done much to demonstrate the richness of African aesthetic standards, they have also tended to obscure other facets of the creativity of African writers who, just like their counterparts all over the world, make ample use of such devices as metaphor, irony, and unreliable narration. After a brief examination of the methodological and epistemological issues that have shaped the elusive field of “African stylistics”, I propose to investigate how contemporary stylistic theories may contribute to the understanding of the multiple forms of creativity found in the works of the US-based Nigerian writer Chris Abani. A self-proclaimed “global Igbo” (after the name of his father’s ethnic group), Abani boldly combines in his work African cosmology with influences from the Catholic and Buddhist traditions, also using formal devices – such as minor sentences and poetic metaphors – whose significance can only be fully appreciated through extensive stylistic analysis. Mainly focusing on Abani’s novella Becoming Abigail (2006), I will suggest that a combination of traditional culture-oriented approaches to African literatures and more typically “mainstream” stylistic techniques is needed to apprehend the Nigerian writer’s complex cross-cultural worldview. [less ▲]

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See detailDevelopmental profiles of GFAP-positive astrocytes in sheep cerebellum
Salouci, Moustafa ULg; Antoine, Nadine ULg; Shikh Al Sook, Mohamad Khir ULg et al

Poster (2015, July 16)

Astroglial cells make up the largest glial population in the brain and play a variety of vital functions in the development of the CNS. Defects in the development of these cells may induce various ... [more ▼]

Astroglial cells make up the largest glial population in the brain and play a variety of vital functions in the development of the CNS. Defects in the development of these cells may induce various neurodegenerative disorders and result in neural disease. The aim of this study is to investigate the normal development of astrocytes in sheep in various zones of the cerebellum during the different stages of gestation. 19 ovine fetuses, one lamb in the first postnatal week and three adult sheep. Sections of the cerebellum were embedded in paraffin and processed for immunohistochemistry for GFAP. The current study indicates that the first appearance of astrocytes occurs around the 8th week of gestation from restricted zones in the cerebellum. Bergmann cells were present around the 15th week of gestation. Our findings suggest that the maturation of astrocytes begins in the caudal parts of the cerebellum from their initial ventral regions to dorsal regions radially within the white matter followed by the more rostral parts of the cerebellum and that the astrocytes proliferate in the vermis before the cerebellar hemispheres. Our study provide a bases for future studies focusing on the pathological changes in the CNS of both human and sheep. [less ▲]

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See detailMetabolomics analysis of Galium odoratum (L.) Scop.: impact of the plant population origin and growth conditions.
Ledoux, Allison ULg; Martin, Bertrand; De Tullio, Pascal ULg et al

Poster (2015, July 16)

Galium odoratum is a plant used in traditional medicine and to prepare beverages. This work aimed at studying the impact of plant origin and growth conditions on the metabolite content of the plant ... [more ▼]

Galium odoratum is a plant used in traditional medicine and to prepare beverages. This work aimed at studying the impact of plant origin and growth conditions on the metabolite content of the plant. Material and methods- Aerial biomass of Galium odoratum was collected from five natural populations (in situ conditions) and from controlled environment (ex situ conditions). Results- Quantitative analysis of selected phytochemicals including phenylpropranoids and iridoids showed clear differences between the plants from nature and those of controlled growth conditions as well as internal variation within the group. The metabolomic approach emphasized the decrease of the secondary metabolites pool paralleled by an increase of the carbohydrates in ex situ conditions. Conclusion- Metabolomics approaches using 1H-NMR and HPLC is worth to consider for studying the impact of climate factors on the regulation of the phytochemical profile in relation to the origin of the plant material. [less ▲]

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See detailPersonnalité antisociale et psychopathologie
Englebert, Jérôme ULg

Conference (2015, July 14)

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes ... [more ▼]

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes contradictions propres au diagnostic qui nous mèneront à l’identification du critère « primaire » de cette entité qui est l’« incapacité à se conformer aux lois et normes sociales ». Nous confronterons ensuite à des situations cliniques l’hétérogénéité des profils pouvant répondre à ce diagnostic. Nos constats nous conduiront à mettre en doute la validité apparente du concept de personnalité antisociale, puisqu’il recouvre des modes de fonctionnement psychologique variés. La valeur discriminative faible, en matière de fonctionnement psychologique, suggère que c’est une dimension autre que psychopathologique qui organise ce diagnostic. Dénuée de toute attention pour les modes d’interactions, pour le vécu émotionnel et pour les états de subjectivité, la notion de personnalité antisociale ne porte pas d’intérêt à l’individu qu’elle catégorise, mais bien à l’acte délinquant commis par ce dernier. Nous conclurons sur le constat de l’absence de dimension psychopathologique de la personnalité antisociale, qui se révèle être un diagnostic principalement criminologique, à l’inverse des fondements de l’éthique psychopathologique. [less ▲]

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See detailEarly Carboniferous events along the north-eastern Gondwanan margin: an example from the Mobarak Formation of the Central Alborz Mountains, Northern Iran.
Sardar Abadi, Mehrdad ULg; Da Silva, Anne-Christine ULg; Poty, Edouard ULg et al

Poster (2015, July 14)

The transition from the Late Devonian to the Early Carboniferous was marked by tectonic events, environmental change and global oceanic biological turnover that influenced sedimentary regimes. The end ... [more ▼]

The transition from the Late Devonian to the Early Carboniferous was marked by tectonic events, environmental change and global oceanic biological turnover that influenced sedimentary regimes. The end-Devonian faunal extinction event, for example, eliminated most of the reef building taxa, which, coupled with an increasing rate of subsidence in response to the opening of the Paleo–Tethys and a sea-ward shift of carbonate factories during the Lower Carboniferous, led to the formation of extensive carbonate ramp platforms along the Laurasian and Gondwanan margins. This development has already been reported from the western Gondwanan and southern Laurasian margins but not from northern to north-eastern Gondwanan margin yet. We aim to improve the knowledge on the main factors controlling the development and growth of carbonate ramps during the Lower Carboniferous by examining the Alborz basin along the northern margin of Gondwana. The Lower Carboniferous Mobarak Formation records the development of a storm-sensitive pervasive carbonate factory on the southern Paleo-Tethys passive margin following the opening of the Paleo-Tethys Ocean into the Alborz basin along the northern margin of Gondwana. Four outcrops in the central Alborz Mountains were studied: the Jaban, Aroo, Shahmirzad and Labnesar sections. Four events have been described as the principal factors controlling carbonate platform evolution in the Lower Carboniferous: (1) A transgression linked to global temperature rise in the Early Tournaisian (Middle Hastarain) resulted in the formation of thick-bedded argillaceous limestones. This interval is represented by massive beds of dark mudstones–wackestones to packstones that laterally interfinger with finely laminated limestones, and with bed thickness ranging on the centimeter to meter scale. This interval correlates with Lower Tournaisian nodular to argillaceous limestones of the Moravia Basin (Czech Republic), the Rhenish Slate Mountains (Poland) and the Dinant Basin (Belgium). (2) Late Hastarian–Early Ivorian glaciations were identified in Southern Gondwana but had not been evidenced in Northern Gondwana yet. This glaciation regime is recorded through the appearance of inner-ramp channel-form facies in mid– and outer-ramp settings. (3) During Late Ivorian–Early Visean?, a differentiation block faulting regime along the basin’s margin caused uplift of the westernmost parts of the Alborz basin and resulted in a sub-marine collapse in the eastern part of the central basin. This caused vast sub-aerial exposure and brecciation the top of the Mobarak Formation at the Jaban and Aroo sections. The sub-marine collapse was recorded through the occurrence of Zoophycos bearing fine-grained limestones in the top of the Labnesar and Shahmirzad sections. (4) Tectonic activity that coincided with considerable and abrupt sea level falls as an indirect consequence of the Viséan and Serpukhovian glaciations phases. This progressive sea level drop led to the stagnation of the carbonate factory, which is expressed as an erosional surface at the top of the Mobarak Formation. [less ▲]

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See detailDevelopment of a simple approach for ultrasensitive detection of bisphenols by multiplexed surface enhanced Raman scattering
De Bleye, Charlotte ULg; Dumont, Elodie ULg; Netchacovitch, Lauranne ULg et al

Poster (2015, July 13)

A very simple, cheap and fast SERS method using functionalized silver nanoparticles was developed to detect bisphenols. This method was applied for the semi-quantitative detection of bisphenol A (BPA ... [more ▼]

A very simple, cheap and fast SERS method using functionalized silver nanoparticles was developed to detect bisphenols. This method was applied for the semi-quantitative detection of bisphenol A (BPA), bisphenol B (BPB) and bisphenol F (BPF) separately. Afterwards, a feasibility study of performing a multiplex SERS detection of BPA, BPB and BPF was successfully carried out. Finally, this developed method was applied on real samples which were solutions comprising cash receipts collected from different stores. [less ▲]

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See detailPRESSÃO PARCIAL (PCO2) E FLUXO DE DIÓXIDO DE CARBONO (CO2) EM AMBIENTES DE VÁRZEA AMAZÔNICOS
Amaral, JHF; Barbosa; Kasper, D et al

Conference (2015, July 12)

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See detailAlgorithmic aspects of converting surface mesh data to volumetric images
Plougonven, Erwan ULg; Léonard, Angélique ULg

Conference (2015, July 09)

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data ... [more ▼]

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data, point sets, finite elements, vector fields, implicit surfaces, graphs, basic shapes (spheres, cylinders, or cubes), etc. The work presented here discusses the problem of converting a triangulated surface mesh to a 3D image, a need that arises for example when using active surface-type segmentation methods of 3D images, shape-fitting, or combining data from laser surface scanning with 3D imaging. During the course of numerous projects, two main classes of mesh-to-image conversions have appeared: those identifying voxels (pixels in a 3D image) that intersect the mesh, or voxels that are contained in the mesh, supposing it defines a closed surface. [less ▲]

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See detailDeterministic Manufacturing constraints for Optimal Distribution in the Case of Additive Manufacturing
Bauduin, Simon ULg; Collet, Maxime ULg; Duysinx, Pierre ULg et al

Conference (2015, July 09)

An overview of the difficulties of coupling additive manufacturing to topology optimization with various solution founded and implemented.

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See detailA probabilistic multi-scale model for polycrystalline MEMS resonators
Lucas, Vincent ULg; Wu, Ling ULg; Paquay, Stéphane et al

Conference (2015, July 09)

The size of micro-electro-mechanical systems (MEMS) is only one or two orders of magnitude higher than the size of their micro-structure, i.e. their grain size. As a result, the structural properties ... [more ▼]

The size of micro-electro-mechanical systems (MEMS) is only one or two orders of magnitude higher than the size of their micro-structure, i.e. their grain size. As a result, the structural properties exhibit a scatter. As an example we study the beam resonator illustrated in Fig. 1(a), made of poly-silicon material, in which each grain has a random orientation. Solving the problem with a full direct numerical simulation combined to a Monte-Carlo method allows the probability density function to be computed as illustrated in Fig. 1(b). However this methodology is computationally expensive due to the number of degrees of freedom required to study one sample, motivating the development of a non-deterministic 3-scale approach [3]. In a multiscale approach, at each macro-point of the macro-structure, the resolution of a microscale boundary value problem relates the macro-stress tensor to the macro-strain tensor. At the micro-level, the macro-point is viewed as the center of a Representative Volume Element (RVE). The resolution of the micro-scale boundary problem can be performed using finite-element simulations, as in the computational homogenization framework, e.g. [2]. However, to be representative, the micro-volume-element should have a size much bigger than the microstructure size. In the context of the MEMS resonator, this representativity is lost and Statistical Volume Elements (SVE) are considered. These SVEs are generated under the form of a Voronoi tessellation with a random orientation for each silicon grain. Hence, a Monte-Carlo procedure combined with a homogenization technique allows a distribution of the material tensor at the meso-scale to be estimated. The correlation between the meso-scale material tensors of two SVEs separated by a given distance can also be evaluated. A generator at the meso-scale based on the spectral method [4] is implemented. The generator [3] accounts for a lower bound [1] of the meso-scale material tensor in order to ensure the existence of the second-order moment of the Frobenius norm of the generated material tensor inverse [5]. Using the random meso-scale field obtained with the meso-scale generator, which accounts for the spatial correlation, a Monte-Carlo method can be used at the macro-scale to predict the probabilistic behavior of the MEMS resonator. [less ▲]

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See detailDe "Poétique" à "Points Essais" : (ré)invention du livre ?
Lorent, Fanny ULg

Conference (2015, July 08)

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See detailBeyond indiscipline of Labor Market Intermediaries : The Case of Public Employment Services and Private Providers Partnerships
Remy, Céline ULg; Beuker, Laura ULg; Gérard, Julie ULg

Conference (2015, July 08)

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling ... [more ▼]

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling readability needs and modernization of Public Employment Services (PES) have appeared. Meanwhile, a spectacular growth of private employment operators - market and non-market - was recognized by the International Labor Organization in all member states, in order to respond effectively to the increased requests of support and training for the beneficiaries of the PES. In this new context, PES are invited by the European Union (EU) – particularly through its multiple directives – to rethink and reposition their traditional activities of placement, training and support for jobseekers according to a "mixed" management of the labor market. Therefore, PES entrust operation and management of their activities to private providers, as part of a contractual agreement. In this way, these operators provide a "back office function for SPE via a system of delegation governed by a specific division of labor formalized in a partnership agreement between PES and the private provider". Thus, these private labor market intermediaries (LMI’s) as active members on the public orders market work both on their own behalf and on behalf of the public authority. These new collaborations, qualified public-private partnerships (PPPs), allow PES to outsource and delegate a part of their missions they could not achieve internally. So PES combine the role of "actor" and the role of "manager" / "principal" in the labor market. To facilitate the coordination of their activities with the private sector, PES made the decision to create a partnerships service. The officers of this service have the mission to oversee this new form of regulation of the labor market. While collaboration rules are initially determined by the PES, the agents are required to implement them and have the private operators following them. Our interest is to study how these actors – or stakeholder of the PPPs – implement this public action device. Despite differences in both organizational and cultural (for instance bureaucratic rigidity versus informal structure, constraint reporting, management autonomy, etc.), public and private actors work together to serve community and beneficiaries of the PES for their professional integration in the labor market. To analyze how these actors interact and live the partnership relationship, established between agreement and disagreement, we will rely on the economy of conventions and especially on the theoretical contributions of the Theory of justification. In this way, we will identify the different logics of action (present in the merchant, civic, industrial worlds, etc.) that guide the practices of stakeholders, from their discourse and in particular the underlying arguments to justify their actions. Our analysis is rooted in empirical material composed of semi-structured interviews (N=89) and various observations of interactions made within the partnership services and with providers (N=132). These observations focused on three key moments in the life of the partnership: the selection of projects, the monitoring and evaluation of projects by the agents. With this approach, our goal is twofold. On the one hand, we want to highlight the moments when the actors "interpret" the regulatory framework that structure their actions within the partnership relationship. On the other hand, we want to understand the arguments used by actors to justify and legitimize their indiscipline. [less ▲]

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See detailStress constrained topology optimization for additive manufacturing: Specific character and solution aspects
Duysinx, Pierre ULg

Conference (2015, July 07)

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress ... [more ▼]

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress constraints are rather limited (Duysinx & Bendsoe, 1998). More recently the generalized shape optimization approach using level set methods (see for instance Allaire, Jouve, Troader, 2004, Belytchko, Xiao, Parimi, 2003) has followed the tracks of topology optimization and has mainly been focusing on compliance minimization problems. The ‘compliance type’ formulation has produced quite interesting results in many problems because controlling the energy and the displacements under the loads is generally favourable for deflection control and because, for one load case, the compliance minimization leads to a fully stressed design nearly everywhere in the structure. However there are theoretical results that clearly show that the strongest and the stiffest structural layout can be quite different. As demonstrated in Rozvany & Birker (1994) truss topology optimization can lead to different results when there are several load cases, different stress limits in tension and compression, or when there are several materials involved. Therefore, the first goal of the paper points out the importance of considering stress constraints as soon as the preliminary design phase, that is, to include stress constraints in the topology optimization problem. Revisiting some contributions of the authors, this paper aims at illustrating the key role of stress constraints in the framework of topology optimization of continuum structures. The recent developments are able to treat: • Integrated stress criteria (i.e. global) relaxed stress constraints that aggregate the stress constraints in each finite element in order to be able to circumvent the large scale character of the local stress constraints. • Stress criteria that are able to tackle non equal stress limits in tension and compression. The usual von Mises criterion is unable to predict real-life designs when the structure is made of materials with unequal stress limits like concrete or composite materials. These different behaviours in tension and compression result in quite specific designs. Numerical applications make possible to point out the different nature of structural lay out for maximum strength and maximum stiffness. This one is clearly demonstrated in two kinds of particular situations: once several load cases are considered and when unequal stress limits in tension and compression are involved. The second contribution of the paper deals with the solution aspects of large scale constrained optimization problems. Because of the huge number of design variables, dual methods combined with local convex approximations such as CONLIN (Fleury, 1989) or MMA (Svanberg, 1987) are well indicated to solve classical topology optimization methods. However stress constrained problems introduce also a so large number of active constraints that one comes to a rather delicate situation. We show that the optimizer effort increases mostly as the cube of the number of constraints. In order to circumvent the problem, the idea developed in the paper is to combine first or second order approximations (Bruyneel, Duysinx, Fleury, 2002) with zero order approximations of stress constraints, especially for the subset of restrictions that are likely not to be active or not to change too fast. At first the paper presents the way to derive zero-order approximations of -relaxed stress constraints (that is necessary to cope with the singularity phenomenon of stress constraints in topology optimization). Then the proposed hybrid approach mixing approximation of different orders is benchmarked on numerical applications illustrating the reduction of computation time for solving optimization problems without sacrifying to the robustness and efficiency. Numerical applications will investigate topology optimized benchmark examples combined with additive manufacturing fabrication to illustrate the developments. [less ▲]

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See detailMethane distributions and sea-to-air fluxes in the South China Sea and the West Philippines Sea
Tseng; Chen; Borges, Alberto ULg et al

Poster (2015, July 07)

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See detailModelling Uncertainties in Long-Term Predictions of Urban Growth: A Coupled Cellular Automata and Agent-Based Approach
El Saeid Mustafa, Ahmed Mohamed ULg; Saadi, Ismaïl ULg; Cools, Mario ULg et al

in Ferreira, Joseph; Goodspeed, Robert (Eds.) Proceedings of CUPUM 2015 (2015, July 07)

Modelling the growth of urban settlements is of considerable interest for different applications, amongst which integrated flood management. This study aims at modelling urban growth for a long time ... [more ▼]

Modelling the growth of urban settlements is of considerable interest for different applications, amongst which integrated flood management. This study aims at modelling urban growth for a long time horizon up to 2100 and to integrate the model outcomes with a hydrological model for the same time horizon. Forecasting land-use change over such time frames entails very significant uncertainties. In this regard, the main focus of this paper is attributed to the handling of uncertainty in an urban growth model. To this end, we examine a Monte Carlo Simulation method, which is integrated in the proposed urban growth model. Transition probabilities for each non-urban cell are estimated by a coupled Cellular Automata-Agent-Based ap-proach. The results help to handle uncertainty over long time horizons and to assess the increment in degree of uncertainty at every time-step. [less ▲]

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See detailA Non-Local Damage-Enhanced Incremental-Secant Mean-Field-Homogenization For Composite Laminate Failure Predictions
Wu, Ling ULg; Adam, Laurent; Doghri, Issam et al

Conference (2015, July 06)

Recently, the authors have presented an incremental-secant mean-field homogenisation (MFH) process for non-linear composite materials [4]. In this formulation, a virtual elastic unloading is applied to ... [more ▼]

Recently, the authors have presented an incremental-secant mean-field homogenisation (MFH) process for non-linear composite materials [4]. In this formulation, a virtual elastic unloading is applied to evaluate the virtual residual stress and strain states reached in each elasto-plastic phase. These virtual states are then used as a starting point to apply a secant homogenization method. This incremental-secant MFH process can handle non-proportional and nonmonotonic loadings, and naturally possesses an isotropic instantaneous stiffness operator to be used in the Eshelby tensor. This incremental-secant MFH homogenization can account for the first and second statistical moment estimation of the current yield stress in the composite phases during the computation of the plastic flow. When accounting for a second statistical moment estimation, the plastic yield in the composite material phases is captured with a higher accuracy, improving the predictions, mainly in the case of short fiber composite materials [6], see Fig. 1(a). The incremental MFH can handle material softening when extended to include a damage model. Indeed, as the secant formulation is applied from an unloaded state, the inclusion phase can be elastically unloaded during the softening of the matrix phase, contrarily to the case of the incremental-tangent method [3, 5], see Fig. 1(b). Moreover, when formulating the damage model in the composite phases in a non-local way, as with the non-local implicit approach, [1, 2], the MFH scheme can be used to model strain localization in composite structures [5], without suffering from the loss of the solution uniqueness. [less ▲]

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See detailPhytoplankton abundance and diversity in the Congo river at high and low waters
Stoyneva, MP; Descy, JP; Bouillon, S et al

Conference (2015, July 05)

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See detailLa paix de Westphalie (1648) : une rupture dans l’histoire diplomatique du Saint-Siège ? Confessionnalisation et médiation pontificale en question.
Regibeau, Julien ULg

Conference (2015, July 04)

La signature des traités de Westphalie, en 1648, a longtemps été considérée comme une rupture nette dans l’histoire politico-religieuse. Elle aurait conduit à l’effondrement de la christianitas médiévale ... [more ▼]

La signature des traités de Westphalie, en 1648, a longtemps été considérée comme une rupture nette dans l’histoire politico-religieuse. Elle aurait conduit à l’effondrement de la christianitas médiévale et à la naissance de l’Europe des États modernes . Ce changement de paradigme supposerait l’échec à long terme de la politique du Saint-Siège. L’historiographie récente permet cependant de revoir cette double interprétation, montrant notamment que le rôle diplomatique joué par Rome lors des négociations en Westphalie est plus complexe. Le but de ma communication est de réévaluer la théorie qui voudrait que la paix de Westphalie soit une rupture pour l’histoire des relations internationales et, par voie de conséquence, pour la diplomatie pontificale. Premièrement, je mets en avant les critères qui poussent régulièrement les historiens à envisager cette paix comme une défaite de Rome. Cette première partie m’entraine ensuite à définir rapidement le concept de confessionnalisation des relations internationales et à montrer qu’il est aujourd’hui réinterrogé par la recherche. Ce concept fait de la lutte confessionnelle le principal facteur structurant les relations internationales entre 1550 et 1650. Or il semble aujourd’hui peu à même d’expliquer toute la diversité des discours et des pratiques qui apparaissent alors dans les correspondances diplomatiques, y compris celles des ambassadeurs du Saint-Siège. Dans un troisième temps, je me concentre plus spécifiquement sur la figure du pape comme padre comune des princes catholiques et donc médiateur de leurs conflits. Ce rôle mérite d’être appréhendé dans le détail de chaque négociation. L’étude de la médiation des nonces ordinaires à l’époque des congrès en Westphalie permettrait ainsi de proposer une nouvelle lecture du rôle joué par la papauté à l’occasion de cette paix. Cela permettrait également d’adjoindre, à la temporalité de la confessionnalisation, d’autres temporalités parallèles. [less ▲]

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See detailLimites temporelles et conceptualisation de l'écrivain
Daubercies, Laurence ULg

Conference (2015, July 04)

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See detailSynécismes et transformations du paysage religieux en Grèce antique
Palamidis, Alaya ULg

Conference (2015, July 03)

Detailed reference viewed: 22 (2 ULg)
See detailMaking-doing sensory perception: how to teach taste
Vangeebergen, Thomas ULg

Conference (2015, July 02)

Imagine a course of “olfaction and tasting”, in a notorious professional school for flavourist and perfumers in France. The aim of the teacher is to instil sensory referential sources in students, by the ... [more ▼]

Imagine a course of “olfaction and tasting”, in a notorious professional school for flavourist and perfumers in France. The aim of the teacher is to instil sensory referential sources in students, by the appropriation of a rigorous vocabulary and through practical tries of molecules and preparations. To name, to compare, to memorize, to describe and to value these substances are the tasks of the group during two years. As the general topic of the research was to understand professional skills about taste, one of the issues consisted in studying the development of these specific abilities. The focus was on the techniques deployed to install a sensory common frame, alternatively through a research of a bottom- up consensus and some imposed tags. The teacher, who has to transfer a substantial amount of sensory references to the class in narrow times, and to make them able to master those notions, has to face to a double constraint. She must transmit a core-sensorium, but at the same time has to support students’ own contributions, in mode to open the reference document to necessary enrichments. More than « actors », or « informants », the teacher and the students were also masters for me, by contributing to my sensory education. But also when they have confronted me to delicates questions and issues, sometimes against my own first researches. They were what I called though co-inquirer, proposing contradictory and resistant interpretations of the world, teaching me how to realize the study of sensory. [less ▲]

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See detailMalentendu visuel et folie : Test de Rorschach et hyper-conscience
Englebert, Jérôme ULg

Conference (2015, July 02)

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See detailSurveillance à long terme de l'atmosphère terrestre depuis la station du Jungfraujoch
Mahieu, Emmanuel ULg

Conference (2015, July 02)

Nous présentons une vue d'ensemble des activités menées par les chercheurs de l'Université de Liège à la station scientifique internationale du Jungfraujoch, depuis les observations infrarouges pionnières ... [more ▼]

Nous présentons une vue d'ensemble des activités menées par les chercheurs de l'Université de Liège à la station scientifique internationale du Jungfraujoch, depuis les observations infrarouges pionnières effectuées à ce site par le Pr Migeotte en 1950-1951. L'accent est mis sur les données géophysiques et les séries temporelles déduites pour les constituants de l'atmosphère influençant le climat. [less ▲]

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See detailSuppression of simulated self-excited oscillation using smart materials on flexible wing structure
Abdul Razak, N.; Nasip, N. S.; Hawari, A. F. et al

in Proceedings of the International Forum on Aeroelasticity and Structural Dynamics, IFASD 2015 (2015, July 01)

Suppression of simulated self-excited oscillation due to aeroelastic effects using piezoelectric patches is reported. The focus of the present work is suppressing simulated flutter oscillation using ... [more ▼]

Suppression of simulated self-excited oscillation due to aeroelastic effects using piezoelectric patches is reported. The focus of the present work is suppressing simulated flutter oscillation using piezoelectric patches bonded to the wing structure. First, a clean wing is exposed to airflow in the wind tunnel where it experienced limited amplitude oscillation. The responses were recorded. This is followed by bonding piezoelectric patches to the identical wing that was tested in the wind tunnel. Two of the patches were used as actuators to simulate self-excited oscillation in a control manner. The selected mode for excitation is 1st bending mode. The other two patches were used as suppressor for active control using negative velocity feedback Single-Input, Single-Output approach. The single input signal for negative feedback is also sensed using piezoelectric patches. The controller manages to suppress the simulated flutter response to a lower oscillation amplitude values. This works demonstrated the used of piezoelectric material as actuator to reproduce the oscillation amplitude during self-excited oscillation and suppress the oscillation at the same time. [less ▲]

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See detailComposite hydraulic modeling to design a complex dam spillway
Erpicum, Sébastien ULg; Dewals, Benjamin ULg; Archambeau, Pierre ULg et al

Conference (2015, July 01)

The paper presents the application of a composite hydraulic modeling approach to the rehabilitation studies of a complex dam spillway. First, a physical scale model of the existing works has been built ... [more ▼]

The paper presents the application of a composite hydraulic modeling approach to the rehabilitation studies of a complex dam spillway. First, a physical scale model of the existing works has been built and operated. It enabled to define very accurately the actual discharge capacity and to validate a numerical model of the system. Second, the numerical model has been used to rapidly test several rehabilitation solutions. Finally, the final design has been validated and optimized using the physical model. The paper shows how composite hydraulic modeling enables to combine the inherent advantages of physical and numerical modeling approaches, which are complementary, while being beneficial to the delay as well as the quality of the analysis. [less ▲]

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See detailGaz à effet de serre indirects et qualité de l'air aux latitudes moyennes de l'hémisphère nord : tendances à long terme et variabilité déduites de télémesures effectuées au Jungfraujoch (Alpes suisses, 3580 m)
Franco, Bruno ULg; Bader, Whitney ULg; Lejeune, Bernard ULg et al

Conference (2015, July 01)

Indirect greenhouse gases and air quality at Northern Hemisphere mid-latitudes: long-term trends and variability derived from ground-based remote sensing at Jungfraujoch (Swiss Alps, 3580 m a.s.l.). We ... [more ▼]

Indirect greenhouse gases and air quality at Northern Hemisphere mid-latitudes: long-term trends and variability derived from ground-based remote sensing at Jungfraujoch (Swiss Alps, 3580 m a.s.l.). We present an overview of recent investigations conducted by the Solar and Atmospheric Physics Infrared Group at the University of Liège and dedicated to the long-term monitoring of atmospheric gases with an indirect greenhouse effect and affecting air quality at Northern Hemisphere mid-latitudes. Gas concentrations are derived from high-resolution solar spectra recorded at the Jungfraujoch station (Swiss Alps, 46.5° N, 8.0° E, 3580 m a.s.l.), using Fourier transform infrared spectrometers. Time series obtained from these observations, along with satellite measurements and simulations from numerical models, allow for the study of both variability and recent evolution of these species and are critical for air quality monitoring and understanding climate changes. [less ▲]

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See detailA new test of uniformity for object orientations in astronomy
Pelgrims, Vincent ULg

in Heavens, A. F.; Starck, J.-L.; Krone-Martins, A. (Eds.) Statistical Challenges in 21st Century Cosmology (2015, July 01)

We briefly present a new coordinate-invariant statistical test dedicated to the study of the orientations of transverse quantities of non-uniformly distributed sources on the celestial sphere. These ... [more ▼]

We briefly present a new coordinate-invariant statistical test dedicated to the study of the orientations of transverse quantities of non-uniformly distributed sources on the celestial sphere. These quantities can be projected spin-axes or polarization vectors of astronomical sources. [less ▲]

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See detailDevelopment of quantification methods applied to HSS alloys for carbides volume fraction and grain size assessments
Tchuindjang, Jérôme Tchoufack ULg; Paydas, Hakan ULg; Hashemi, Seyedeh Neda ULg et al

Poster (2015, July)

High speed steels (HSS) are used in applications where enhanced mechanical properties together with hot oxidation and wear resistances are required. Such an improved physico-chemical behaviour is mainly ... [more ▼]

High speed steels (HSS) are used in applications where enhanced mechanical properties together with hot oxidation and wear resistances are required. Such an improved physico-chemical behaviour is mainly due to the presence of primary carbides within the microstructure. Depending of the initial chemical composition several types of carbides can precipitate in HSS such as MC (Nb and V-rich), M2C (Mo and W-rich), Cr-rich M7C3, etc. Two groups of HSS were analysed in this study, which are the so-called cast HSS grades that are manufactured by a centrifugal casting process and the cladded HSS manufactured by laser cladding. Purpose: Quantify the carbide volume fractions and the grain size within HSS grades in order to set correlations between the microstructure and both the mechanical and the tribological properties of the materials. Findings: The metallurgical features such as carbides nature and shape have been determined that are related to the manufacturing process of the studied material, and several methods have been used to quantify the carbide volume fractions and to assess the grain size. [less ▲]

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See detailiPot: Industrial Potato monitoring for the Belgian potato sector using remote sensing and crop growth modelling
Wellens, Joost ULg

in Qu, Dongyu (Ed.) Develop Together for a Better Future (2015 Beijing World Potato Congress) (2015, July)

The Belgian potato processing industry has known a spectacular growth during the last decades. The companies active in this sector (most of them family owned enterprises) have succeeded – together with ... [more ▼]

The Belgian potato processing industry has known a spectacular growth during the last decades. The companies active in this sector (most of them family owned enterprises) have succeeded – together with primary producers and traders – to grow from 500.000 tons of processed potatoes in 1990 till 3.650.000 tons of raw material in 2012. When considering the production (in tons) per habitant, Belgium is ranked on the 4th place with a production of 395 tons per 1.000 inhabitants. Nowhere in the world are higher yields obtained than in Belgium. To keep up its position on the forefront of innovation, the potato processing industries are continuously looking at promising novel technologies that could improve business processes at any stage of growth. The close follow up of parcels on the land as form above is becoming an important tool to improve the quantity and the quality of the potato crop, and reduce the risks in order to plan the storage, packaging or processing and as such to strengthen the competiveness of the Belgian potato in a global market. The iPot project, financed by the Belgian Science Policy Office (BELSPO), aims to provide the Belgian potato sector, represented by Belgapom, with near real time information on field condition (weather-soil) and crop development, and with early yield estimates, derived from a combination of satellite images and crop growth models. Satellite images are used since long for crop monitoring at regional level by the public sector. Traditionally, low to medium resolution images, with pixel sizes from 250m to 1km are used for providing information on crop growth and development, and on yield at regional scale. However, the recent launch of constellations of high resolution optical sensors (DMC, Sentinel-2) offering spatially detailed information (20m pixel size) at high frequency (every 2 to 3 days) and at low cost, is creating a (r)evolution in the world of crop monitoring. Automatic processing chains have been developed to derive vegetation indices (NDVI) and biophysical parameters (fAPAR, LAI, fCover). Maps are being derived on a regular basis with for each pixel the actual development stage of the potato crop. This on-line scanning of the growth (phenology) is expected to result in an increased performance of crop growth models and better yield predictions. Once the data for crop phenology are incorporated into the model (B-CGMS), the yield data collected at the parcel level will be assimilated into the model using optimization algorithms to minimize the discrepancies between observed and simulated yield time series in order to improve further yield estimations. The combination of these new earth observation and modelling techniques arose the interest of a new type of users, mainly from the private sector (agro-industry, agricultural insurers, etc.). The iPot project aims to bridge the gap between the latest research efforts regarding crop growth monitoring and the industry. An intuitive web based geo-information platform is being developed to allow both the Belgian potato industry and research centers to access, analyze and combine the data with their own field observations in closed collaboration with the farmers, for improved decision-making. [less ▲]

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See detailCarbides and grain size quantification methods in high speed steel alloys
Tchuindjang, Jérôme Tchoufack ULg; Paydas, Hakan ULg; Hashemi, Seyedeh Neda ULg et al

Conference (2015, July)

High speed steel (HSS) grades are widely used as in highly stressed applications where carbides content promote enhanced mechanical properties together with oxidation and wear resistances. Such a ... [more ▼]

High speed steel (HSS) grades are widely used as in highly stressed applications where carbides content promote enhanced mechanical properties together with oxidation and wear resistances. Such a tribological behaviour is mainly due to the presence of primary carbides. It is thus important to quantify the carbide volume fraction in HSS to correlate this result with the mechanical and tribological properties of the materials. Depending of the steel composition several types of carbides are precipitated in HSS: MC (Nb and V-rich), M2C (Mo and W-rich), Cr-rich M7C3 and some others, depending of the chemical composition. Two groups of HSS were analyzed in this study: cast HSS manufactured by centrifugal casting and cladded HSS manufactured by laser cladding. Depending on the chemical composition and the manufacturing process of the studied material, several methods have been used to quantify the carbide volume fraction and the grain size. [less ▲]

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See detailQuasar radio polarizations align with large quasar group major axes
Pelgrims, Vincent ULg; Hutsemekers, Damien ULg

Poster (2015, July)

Using quasar polarizations and a sample of large quasar groups drawn from the SDSS DR7, we showed that at HIGH REDSHIFTS (z ~ 1.5) the spin axis orientations of black holes are correlated to the major ... [more ▼]

Using quasar polarizations and a sample of large quasar groups drawn from the SDSS DR7, we showed that at HIGH REDSHIFTS (z ~ 1.5) the spin axis orientations of black holes are correlated to the major axes of the groups to which they belong. Inside very rich groups the BH spins are aligned with the major axes. When the richness decreases, the spin axes become preferentially perpendicular. [less ▲]

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See detailMarcel-Henri Jaspar, "Le plus gaullien des Belges" ? Construction et déconstruction d'une réputation (1940-1966)
Genin, Vincent ULg

in Lanneau, Catherine; Depagie, Francis (Eds.) De Gaulle et la Belgique (2015, July)

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See detailHow bioméchanical analysis may help to identify abdominal injury causes in high level tennis
Tubez, François ULg; Forthomme, Bénédicte ULg; Croisier, Jean-Louis ULg et al

Conference (2015, July)

This research studies the case of a professional tennis player who has suffered from a medical tear on the left rectus abdominis muscle after a tennis serve. The goal of the study is to understand whether ... [more ▼]

This research studies the case of a professional tennis player who has suffered from a medical tear on the left rectus abdominis muscle after a tennis serve. The goal of the study is to understand whether the injury could be explained by an inappropriate technique. For this purpose, we analyzed the three dimensions kinematic and kinetic of the serve. We also performed isokinetic tests of the knees. We compared the player to five other professional players. We observed a possible deficit of energy transfer because of an important anterior pelvis tilt. Some compensations of the player during serve could be a possible higher abdominal contraction and a larger shoulder external rotation. These particularities could induce an abdominal overwork that would explain the first injury and may provoke a new injury. [less ▲]

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See detailAlignments of quasar axes with large-scale structures
Hutsemekers, Damien ULg; Braibant, Lorraine ULg; Pelgrims, Vincent ULg et al

Conference (2015, July)

Based on measurements of optical linear polarization of quasars belonging to large groups at redshift ~ 1.3, we found that quasar spin axes are likely parallel to their host large-scale structures. The ... [more ▼]

Based on measurements of optical linear polarization of quasars belonging to large groups at redshift ~ 1.3, we found that quasar spin axes are likely parallel to their host large-scale structures. The observations and the statistical analysis will be reviewed, and interpretations discussed. [less ▲]

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See detailIntégration de tablettes numériques dans la formation des futurs enseignants: une étude de cas
Parlascino, Emmanuelle ULg; Joris, Noémie ULg

Conference (2015, July)

À travers cette recherche, les auteurs visent à mettre en évidence, chez les étudiants, les apports réels, en termes d’apprentissages et de développement professionnel, de situations d’enseignement ... [more ▼]

À travers cette recherche, les auteurs visent à mettre en évidence, chez les étudiants, les apports réels, en termes d’apprentissages et de développement professionnel, de situations d’enseignement intégrant une technologie, à savoir les tablettes numériques. Le groupe d’étude se constitue d’un enseignant en histoire en haute école pédagogique et de trois classes d’étudiants en formation pour devenir enseignants. Ce groupe fera l’objet d’une analyse approfondie au travers d’observations filmées, examinées à l’aide de grilles, et de commentaires réflexifs (de l’enseignant et des étudiants) issus d’entretiens d’autoconfrontation sur divers extraits des situations d’enseignement menées et vécues. Cette méthodologie conduira à croiser plusieurs types d’informations : (1) les objectifs de l’enseignant au moment de préparer la situation d’enseignement, (2) sa perception des apports mis en place à travers la technologie, (3) la perception de ses étudiants et (4) les observations des auteurs. Soucieux de contribuer à l’analyse réflexive sur l’intérêt d’intégrer le numérique en éducation, les auteurs veulent mettre en évidence les apports réels de l’activité, les points de passage obligés et les principales difficultés de sa mise en place. Ces résultats pourront éclairer les enseignants souhaitant se lancer dans ce genre d’activité innovante. [less ▲]

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See detailPhotocatalytic Oxidative Treatment of Waste Water contamined with Pharmaceutical Products
Vreuls, Christelle; Wilmot, Annick; Cludts, Marc et al

Poster (2015, July)

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See detail"On se débrouille", or how to be a good judge when the state lets you down?
Andreetta, Sophie ULg; Kolloch, Annalena

Conference (2015, July)

Over the last couple of years, Beninese magistrates have been on strike for months in a row. In 2012, it was about the Ministry of justice implying corruption issues. In 2013, it was about independence ... [more ▼]

Over the last couple of years, Beninese magistrates have been on strike for months in a row. In 2012, it was about the Ministry of justice implying corruption issues. In 2013, it was about independence and fear of political infringement. In 2014, it was about the most recent appointments. When it comes to judges from the bench, most of them complain about their substantial workload, low pay and poor working conditions. They also highlight the discrepancies between the magistrate’s social status and what their families expect from them, the standards of living that people assume that they have. In short, there seems to be a professional malaise within the Beninese bench, who feel like the state is letting them down, yet judges also insist on the importance of their work, and of doing it right. This is why, for the purpose of this paper, we will be looking at the discourses and representations of Beninese judges on their own social and professional status. What does it mean to be a judge in Benin today? Why do young lawyers choose that professional path over other legal careers? How do they ‘do their job right’ and what are the obstacles to it? Considering both age and gender, we are also trying to look at what it means to be a civil servant today, when the state is no longer the only – or the most promising – employer for legal practitioners. [less ▲]

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See detailComparison of experimental results and numerical modelling of unreinforced load-bearing masonry structures subjected to earthquake loading
Mordant, Christophe ULg; Denoël, Vincent ULg; Degée, Hervé

in Proceedings of the SECED 2015 Conference: Earthquake Risk and Engineering towards a Resilient World (2015, July)

This paper presents a comparison of experimental tests results on unreinforced load-bearing masonry structures subjected to earthquake loading with numerical predictions. First, simple walls are submitted ... [more ▼]

This paper presents a comparison of experimental tests results on unreinforced load-bearing masonry structures subjected to earthquake loading with numerical predictions. First, simple walls are submitted to cyclic and shaking table tests. Some of them include soundproofing devices in order to investigate their influence on the general behaviour in static and dynamic conditions. Additional walls with an opening and T-shaped walls are then tested under cyclic loading. The study is focused on the frame effect, the contribution of the perpendicular wall to the global strength and the efficiency of the connection. These aspects are also studied through shaking table tests on two masonry frames with T- or L-shaped piers. The main information is expressed in terms of force-displacement curves, mechanical properties and energy dissipation for the cyclic tests. The shaking table tests provide results in terms of dynamic and mechanical properties. Comparison of the results with numerical predictions is finally performed thanks to the software TREMURI. [less ▲]

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See detailGlucosinolates and by-products in rapeseed meal related to hydrothermal processing
Quinsac, A.; Carré, P.; Fauconnier, Marie-Laure ULg et al

Poster (2015, July)

Background: For safety reasons, rapeseed meal (RSM) is usually desolventized with strong hydrothermal treatments, leading to various levels of residual glucosinolates (GSL), and protein solubility. The ... [more ▼]

Background: For safety reasons, rapeseed meal (RSM) is usually desolventized with strong hydrothermal treatments, leading to various levels of residual glucosinolates (GSL), and protein solubility. The RSM nutritional quality may be then lowered for monogastrics, due to GSL breakdown products whose reliable and “easy to use” indicators lack. [less ▲]

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See detailDe nationaliteit van Belgische ‘jihadisten’ op de schopstoel : wanneer worden ‘nieuwe’ Belgen ‘echte’ Belgen?
Wautelet, Patrick ULg

Conference (2015, July)

This presentation first gives an overview of the current legal standards for deprivation of nationality based on terrorism in Belgium and France. In a second part, it focuses on the question whether it ... [more ▼]

This presentation first gives an overview of the current legal standards for deprivation of nationality based on terrorism in Belgium and France. In a second part, it focuses on the question whether it may be justified to treat different categories of nationals differently in nationality law and more specifically when dealing with deprivation of nationality. An attempt is made to analyze the French and Belgian legal framework from the angle of the prohibition of discrimination. [less ▲]

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See detailWritten Corrective Feedback: A Case Study
Noiroux, Kevin ULg

Conference (2015, July)

The present study looks at the efficacy of 3 types of written corrective feedback on errors made by French-Speaking High School students writing in English. More than 100 students, taught by 5 different ... [more ▼]

The present study looks at the efficacy of 3 types of written corrective feedback on errors made by French-Speaking High School students writing in English. More than 100 students, taught by 5 different teachers in 3 different schools, participated in the study. Each participant was randomly assigned to a different type of written corrective feedback: underlining, direct correct or explanation. Each time the students wrote a text in their EFL class, I (the researcher) corrected it, selected 10 errors and asked the students to state whether they understood the error. If they understood the error, they were asked to correct and/or explain it, depending on their treatment group. I then analyzed the corpus of more than 2000 errors: all the errors were categorized and the uptake moves (students’ corrections and explanations) verified. Finally, I checked whether there was a positive correlation between error types, types of corrective feedback, and students’ uptake. [less ▲]

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See detailLate Holocene history of the Fuji Five Lakes (Japan)
Lamair, Laura ULg; Hubert, Aurelia ULg; Boes, Evelien et al

Conference (2015, July)

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See detailQuadratization of pseudo-Boolean functions
Crama, Yves ULg; Anthony, Martin; Boros, Endre et al

Conference (2015, July)

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See detailSharing a Car? Yuck, No! An Investigation of Customer Contamination in Access-Based Services
Hazee, Simon ULg; Delcourt, Cécile ULg; Van Vaerenbergh, Yves

Conference (2015, July)

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See detailComparative study of different output metrics for a three weakly coupled resonator sensor
Zhao, Chun; Wood, Graham; Xie, J.B. et al

in Proceedings of Solid-State Sensors, Actuators and Microsystems (Transducers 2015) (2015, July)

This work, for the first time, investigates the characteristics of different output metrics for a three degree-of-freedom (DoF) coupled resonator sensor. The main aspects examined are sensitivity and ... [more ▼]

This work, for the first time, investigates the characteristics of different output metrics for a three degree-of-freedom (DoF) coupled resonator sensor. The main aspects examined are sensitivity and linear range. It is shown from electrical measurements that using the vibration amplitude ratio as an output signal provides improved sensitivity and linearity range, compared to other methods such as shift in eigenstate, mode frequency or amplitude difference. [less ▲]

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See detailComparison of fracture prediction models on sheet metal blanking simulations
Canales Cardenas, Cristian ULg; Boman, Romain ULg; Bussetta et al

Conference (2015, July)

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See detailEtude de l'évolution de l'enneigement dans les Hautes Fagnes (Belgique) au cours des cinquante dernières années à l'aide du modèle climatique régional MAR
Wyard, Coraline ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg

in Erpicum, Michel (Ed.) Actes du XXVIIIe colloque annuel de l’Association Internationale de Climatologie : Modélisations et variabilités (2015, July)

The “Modèle Atmosphérique Régionale” MAR is a regional climate model originally developed to study the polar ice sheets. In this study, the MAR model has been adapted to Belgium in order to study the snow ... [more ▼]

The “Modèle Atmosphérique Régionale” MAR is a regional climate model originally developed to study the polar ice sheets. In this study, the MAR model has been adapted to Belgium in order to study the snow cover evolution of the High Fens (east of Belgium), a region covered by snow on average one to two months per year. As validation, we have sucessfully compared MAR based daily snow heights with snowcam-based and/or laser sensor-based observations over the period 2008-2013. Then, the model has been forced by ERA-Interim since 1958 to study the snow cover evolution during the last fifty years at the summit of Belgium. The results show no significant trend despite global warming. [less ▲]

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See detailDiscovery of a new spore assemblage in the Middle Devonian of Iberian Peninsula
Rial, Gonzalo; Cascales-Miñana, Borja ULg; Gozalo, Rodolfo et al

Conference (2015, July)

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See detailModel reduction for simulating the dynamic behavior of parabolic troughs and a thermocline energy storage in a micro-solar power unit
Dickes, Rémi ULg; Desideri, Adriano ULg; Lemort, Vincent ULg et al

Conference (2015, July)

Micro-scale concentrated solar power plants are characterized by strong transients and mostly operate in off-design working conditions. Both the sizing and the control of these systems are key challenges ... [more ▼]

Micro-scale concentrated solar power plants are characterized by strong transients and mostly operate in off-design working conditions. Both the sizing and the control of these systems are key challenges whose optimization requires powerful dynamic modeling tools. In this context, a system featuring a solar field of parabolic troughs, a thermocline thermal energy storage and a 5kWe organic Rankine cycle (ORC) power unit is modeled in the Modelica language. Model reduction methods applied to the solar field and the thermal storage are investigated and analyzed to improve the computational efficiency of the problem. Each model is described and integrated in the open-source ThermoCycle library. Results of simulation under identical operating conditions are compared and the benefits and limitations of model reduction are assessed. [less ▲]

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See detailTowards precision β-decay measurements with laser cooled 35Ar
Glover, Rohan ULg; Lenaers, Florence ULg; Velten, Philippe et al

Poster (2015, July)

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See detailSemi-empirical correlation to model heat losses along solar parabolic trough collectors
Dickes, Rémi ULg; Lemort, Vincent ULg; Quoilin, Sylvain ULg

Conference (2015, July)

Solar thermal power plants convert sunshine energy into useful heat and electricity by means of solar collectors and a thermodynamic cycle. Among the different solar collector technologies, parabolic ... [more ▼]

Solar thermal power plants convert sunshine energy into useful heat and electricity by means of solar collectors and a thermodynamic cycle. Among the different solar collector technologies, parabolic troughs are nowadays the most widespread together with solar towers. In order to improve the computation speed required to simulate the temperature profile along solar parabolic trough collectors, a correlation estimating the effective heat losses of the receiver is an essential tool. However, the relations found in the literature lack accuracy and do not translate effectively the effects of the operating conditions in all cases. In this work, an alternative correlation is proposed and calibrated with the results of a deterministic model. Better fitting performance is demonstrated when compared to the prediction of the pre-existing correlations. The benefits and limitations of the new correlation are finally assessed. [less ▲]

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See detailAsymmetric limit cycle oscillations in systems with symmetric freeplay
Dimitriadis, Grigorios ULg

in Proceedings of the International Forum on Aeroelasticity and Structural Dynamics, IFASD 2015 (2015, June 30)

In this paper, a simple 2D aeroelastic system with degrees of freedom in pitch, plunge and control surface deflection is investigated with freeplay in the pitch degree of freedom. It is shown that this ... [more ▼]

In this paper, a simple 2D aeroelastic system with degrees of freedom in pitch, plunge and control surface deflection is investigated with freeplay in the pitch degree of freedom. It is shown that this system features a fixed point at the origin as well as two anti-symmetric fixed points. Asymmetric limit cycles that span only two of the three piecewise linear subdomains of the phase plane can orbit these anti-symmetric fixed points. A single three-domain symmetric cycle and two two-domain cycles appear as a result of a grazing bifurcation occurring at the flutter speed of the underlying linear system. The two-domain cycles can undergo further fold, period doubling and torus bifurcations. They can cause both periodic and aperiodic oscillations, including highly chaotic responses at parameter values where they interact strongly. [less ▲]

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See detailLe lecteur de Barthes : jouisseur du judas ?
Lorent, Fanny ULg

Conference (2015, June 30)

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See detailUsing 2D-PIV measurements to compute unsteady aerodynamic loads on a flat plate at high angle of attack
Guissart, Amandine ULg; Bernal, Luis; Dimitriadis, Grigorios ULg et al

in Proceedings of the 16th International Forum on Aeroelasticity and Structural Dynamics, IFASD 2015 (2015, June 30)

This work exposes and discusses results obtained for aerodynamic forces using an indirect calculation based on Particle Image Velocimetry (PIV) measurements. The methodology used is based on the integral ... [more ▼]

This work exposes and discusses results obtained for aerodynamic forces using an indirect calculation based on Particle Image Velocimetry (PIV) measurements. The methodology used is based on the integral formulation of the Navier-Stokes equations and is applied to spatio-temporal data for different flows around a plate with a 16:1 chord-to-thickness ratio at high angle of attack. Experimental data are obtained in a water channel for both a static and a pitching plate. In addition to PIV data, direct measurements of aerodynamic loads are carried out to assess the quality of the indirect calculation. It is demonstrated that this indirect method is able to compute the mean and the temporal evolution of the lift and drag coefficients with a reasonable accuracy. It is also shown that the noise sensitivity of the method can be partly alleviated through the use of Dynamic Mode Decomposition (DMD) as a pre-processing step to smooth the spatio-temporal data. [less ▲]

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See detailERT to monitor the bioremediation of hydrocarbons with Rhodococcus erythropolis T902.1 at a pilot scale
Masy, Thibaut ULg; Caterina, David; Tromme, Olivier et al

Conference (2015, June 30)

Petroleum hydrocarbons (HC) represent the most widespread contaminants in the world and in-situ bioremediation remains a competitive treatment in terms of cost and environmental concerns. However, the ... [more ▼]

Petroleum hydrocarbons (HC) represent the most widespread contaminants in the world and in-situ bioremediation remains a competitive treatment in terms of cost and environmental concerns. However, the efficiency of such a technique (by biostimulation or bioaugmentation) strongly depends on numerous environmental characteristics (heterogeneities of the subsurface structure, soil moisture, oxygen and pollutants bioavailability, microbial niches…) and is still difficult to predict a priori. In order to lower these uncertainties, Electrical Resistivity Tomography (ERT) appears as a valuable non-invasive tool to detect soil heterogeneities and to monitor biodegradation. The main objective of this study was thus to isolate with ERT an electrical signature corresponding to an enhanced biodegrading activity, in an aged HC-contaminated clay loam soil. To achieve it, a pilot tank with metric dimensions (3.6 × 0.9 × 0.6 m) and a recirculating system (which is quite unique for this type of purpose) was built to mimic field conditions and to control the evolution of the bio-physico-chemical parameters (microbial concentration in soil and groundwater, temperature, pH, pO2, redox potential, bulk and fluid conductivities, water flow, hydrocarbon content) through time and space. Five panels of electrodes were placed at different locations in the tank to detect lithological heterogeneities and to monitor the bulk resistivity variations with time-lapse ERT. Compared to a first insufficient biostimulation phase with H2O2 and KNO3, bioaugmentation with Rhodococcus erythropolis T902.1 led to a HC depletion of almost 80% (6900 to 1600 ppm) in 3 months in the center of the contaminated clay, where pollutants were less bioavailable. Furthermore, lithological heterogeneities (clay, sand, gravels) and microbial activities (growth, degradation and biosurfactant production) were successfully discriminated by ERT images obtained during both remediation phases. In the future, this cost-effective technique should be transferred to the field in order to either (i) detect and forecast biodegradation processes before choosing an appropriate remediation technique, or (ii) monitor the efficiency of this biodegradation during an in-situ bioremediation. [less ▲]

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See detailModifications acoustiques de la voix d’enseignantes au cours de la journée et de l’année scolaire
Remacle, Angélique ULg; David, Claire; Petillon, Caroline et al

Conference (2015, June 30)

Introduction Les enseignants font partie des professionnels de la voix, définis comme des travailleurs qui ne peuvent se passer de leur voix dans l’exercice de leur profession, et qui à ce titre ... [more ▼]

Introduction Les enseignants font partie des professionnels de la voix, définis comme des travailleurs qui ne peuvent se passer de leur voix dans l’exercice de leur profession, et qui à ce titre nécessitent une qualité de vocale constante (1). Cette population est particulièrement à risque et constitue le groupe de travailleurs le plus nombreux à consulter les ORL pour cause de dysphonie (2). Dans ce contexte, la recherche tente d’identifier les indices acoustiques de la fatigue vocale dans le but d’améliorer le dépistage précoce des problèmes de voix, leur traitement et leur prévention. Cette étude menée in situ a pour objectif de mettre en évidence des modifications acoustiques et prosodiques consécutives à 1) une journée de travail et 2) cinq mois de travail en milieu scolaire. Méthode La population est constituée de 22 enseignantes du primaire ayant moins de 5 années d’expérience. Pour chaque participante, cinq /a/ tenus ainsi que la lecture d’un texte ont été enregistrés 1) à deux moments de la journée de travail, soit au matin et au soir, et 2) à trois temps de l’année, soit en octobre (T0), en décembre (T1) et en février (T2). Sur les voyelles tenues, nous avons mesuré le temps maximum phonatoire (TMP), la fréquence moyenne, le jitter, le shimmer, et le rapport harmoniques/bruit (HNR). Sur les textes, nous avons mesuré la fréquence moyenne, la variation de fréquence et d’intensité (écart-type), ainsi que des paramètres relatifs au débit de parole (nombre de syllabes par seconde, nombre de pauses et durée moyenne des pauses). Pour chaque paramètre, une ANOVA en mesure répétées (2 moments * 3 temps) a été réalisée. Résultats L’effet principal du moment montre une augmentation de la fréquence moyenne mesurée sur les voyelles et sur le texte suite à une journée de travail (p<.01). Parallèlement, le TMP et le HNR augmentent (p<.01), tandis que le jitter et le shimmer diminuent en fin de journée (p<.05). Les mesures de débit montrent que les enseignantes tendent à faire moins de pauses lors de la lecture de texte en fin de journée, et que ces pauses sont de plus courte durée (p<.05). L’effet principal du temps montre une augmentation de la fréquence moyenne des voyelles et du texte au cours de l’année (p<.01), avec des valeurs plus élevées observées en décembre (T1). Les mesures relatives au débit montrent également une augmentation du nombre de syllabes par seconde (p<.01) et une tendance des locutrices à faire moins de pauses. Conclusion L’évolution des paramètres observés suggère une augmentation de la fatigue vocale et un comportement phonatoire davantage hyperfonctionnel au cours de la journée et au cours de l’année. Les résultats montrent une dégradation vocale majorée au mois de décembre, en comparaison avec les autres moments de l’année. Bibliographie 1.Titze IR, Lemke J, Montequin D. Populations in the U.S. workforce who rely on voice as a primary tool of trade: A preliminary report. Journal of Voice. 1997;11(3):254-259. 2. Remacle, A., Petitfils, C., Lejeune, L., Finck, C., & Morsomme, D. Quel est le profil professionnel des patients consultant en phoniatrie ? 70e Congrès de la Société Française de Phoniatrie, Paris, France. (13 octobre 2014). [less ▲]

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See detailUnsteady Viscous-Inviscid Coupling Simulations of Separated Laminar Flows Around 2D Airfoils
Rothkegel Ide, José Ignacio ULg; Dimitriadis, Grigorios ULg

in Proceedings of the International Forum on Aeroelasticity and Structural Dynamics, IFASD 2015 (2015, June 29)

An interactive boundary layer model has been developed in 2D in order to solve the unsteady flow around an airfoil. The inviscid problem is solved using a panel method, by the discretization of the ... [more ▼]

An interactive boundary layer model has been developed in 2D in order to solve the unsteady flow around an airfoil. The inviscid problem is solved using a panel method, by the discretization of the airfoil into linear-varying vortex panels. The solution of the boundary layer equations is carried out using a finite volume scheme. Viscous-inviscid coupling is preformed by imposing a permeation velocity on the skin panels of the airfoil and the addition of a free wake at each separation point. [less ▲]

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See detailTheoretical and experimental investigation of a structurally and aerodynamically nonlinear pitch and flap wing
Verstraelen, Edouard ULg; Boutet, Johan ULg; Grappasonni, Chiara ULg et al

in Proceedings of the International Forum on Aeroelasticity and Structural Dynamics, IFASD 2015 (2015, June 29)

This paper presents and experimental and theoretical investigation of a novel nonlinear aeroelastic system. It consists of a wing with pitch and flap degrees of freedom, suspended from a leaf spring ... [more ▼]

This paper presents and experimental and theoretical investigation of a novel nonlinear aeroelastic system. It consists of a wing with pitch and flap degrees of freedom, suspended from a leaf spring secured in a nonlinear clamp. Both the structural and the aerodynamic forces acting on the wing can be nonlinear, depending on the amplitude of oscillations. Wind tunnel experiments show that the system undergoes a supercritical Hopf bifurcation that leads to small amplitude limit cycle oscillations. At a particular airspeed, the pitch amplitude jumps to a much higher value and dynamic stall starts to occur. Three mathematical models of the system are formulated, one based on linear aerodynamics and two based on the Leishman-Beddoes dynamic stall model. The objective of the modelling is to determine whether the jump in pitch oscillation amplitude is due to dynamic stall. The predictions for amplitude, frequency and mean angle of the limit cycle oscillations are compared to the experimental observations. All three models predict the small amplitude oscillations with satisfactory accuracy. The complete Leishman-Beddoes model predicts the occurrence of a jump in pitch amplitude but the magnitude of this jump is signi cantly overestimated. The other two models completely fail to model the jump. The failure of the Leishman-Beddoes model to predict the correct post-jump oscillation amplitude may be due to the values selected for the model parameters. [less ▲]

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See detailA comparative study for simulation of heat transport in large district heating network
Sartor, Kevin ULg; Thomas, David ULg; Dewallef, Pierre ULg

in Prooceedings of ECOS 2015 (2015, June 29)

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See detailComparative transcriptomic analysis of the distinct pancreatic cell types
Peers, Bernard ULg

Conference (2015, June 28)

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See detailDUSP3 Phosphatase Deficiency or Inhibition Limits Platelet Activation and Arterial Thrombosis
Tautz, Lutz; Rahmouni, Souad ULg; Oury, Cécile ULg et al

Conference (2015, June 27)

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See detailAssessment of climate change effects on groundwater resource in transient conditions
Goderniaux, Pascal; Wildemeersch, Samuel; Brouyère, Serge ULg et al

Conference (2015, June 27)

A sophisticated transient weather generator (WG) in combination with an integrated surface-subsurface hydrological model (HydroGeoSphere) are used for producing a stochastic generation of large numbers of ... [more ▼]

A sophisticated transient weather generator (WG) in combination with an integrated surface-subsurface hydrological model (HydroGeoSphere) are used for producing a stochastic generation of large numbers of equiprobable climatic time series, representing transient climate change, and assess impacts on groundwater resources in a probabilistic way. The modelling approach, involving the catchment-scale fully integrated surface-subsurface model, is described in Goderniaux et al. [2009]. Biased-corrected climate change scenarios are applied as input of the hydrological model to quantify their impact on groundwater resources. In Goderniaux et al. [2011], the integrated model is used in combination with a stochastic daily weather generator (WG). This WG allowed generating a large number of equiprobable climate change scenarios representative of a full transient climate between 2010 and 2085. These scenarios enabled to account for the transient nature of the future climate change, and to assess the uncertainty related to the weather natural variability. The downscaling method considers changes in the climatic means, but also in the distribution of wet and dry days. This new methodology is applied for the unconfined chalky aquifer of the Geer catchment in Belgium. A general decrease of the mean groundwater piezometric heads, has been calculated. The approach allowed also to assess different uncertainty sources: (1) the uncertainty linked to the calibration of the hydrological model, using 'UCODE_2005'; (2) the uncertainty linked to the global and regional climatic models (GCMs and RCMs), by using a multi-model ensemble; (3) the uncertainty linked to the natural variability of the weather, by using stochastic climate change scenarios. 30 equiprobable climate change scenarios from 2010 to 2085 have been generated for each of 6 different RCMs. Results show that although the 95% confidence intervals calculated around projected groundwater levels remain large, the climate change signal becomes stronger than that of natural climate variability by 2085. The WG ability to simulate transient climate change enabled the assessment of the likely timescale and associated uncertainty of a specific impact. This methodology constitutes a real improvement in the field of groundwater projections under transient climate change conditions as it enables water managers to analyse risks and take decisions with full knowledge of projected impact and their degree of confidence. [less ▲]

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See detailTowards the identification of cis-elements responsible for the high expression of HMA4, an essential gene for Zn hyperaccumulation in Arabidopsis halleri.
Spielmann, Julien ULg; Nouet, Cécile ULg; Scheepers, Maxime ULg et al

Conference (2015, June 26)

A. halleri is a Zn and Cd hypertolerant and hyperaccumulator plant which stores metals in shoot vacuoles. One key step for hyperaccumulation is a highly efficient root-to-shoot translocation of metals ... [more ▼]

A. halleri is a Zn and Cd hypertolerant and hyperaccumulator plant which stores metals in shoot vacuoles. One key step for hyperaccumulation is a highly efficient root-to-shoot translocation of metals. The Zn/Cd plasmamembrane pump HMA4 (heavy metal ATPase 4) plays a central role in this process and is involved in xylem loading/unloading. Moreover, HMA4 is overexpressed in A. halleri compare to its non-tolerant and non-hyperaccumulator sister, Arabidopsis thaliana. The HMA4 overexpression is determined by a combination of gene triplication and cis-regulatory changes increasing transcription levels of each three HMA4 copies. In this study, we are focusing on the two most active HMA4 promoters and we aim to identify the cis-elements underlying high expression of HMA4 in A. halleri using promoter-reporter constructs. Through deletion analysis, two important regions for a high expression have been identified. Ongoing analysis of more detailed deletions will be presented. [less ▲]

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