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See detailIntegrated microfluidic device for in line SERS detection for glyphosate and related metabolites
Emonds-Alt, Gauthier ULg; Malherbe, Cédric ULg; Monbaliu, Jean-Christophe ULg et al

Poster (2016, July 07)

The goal of this work is to develop a quantitative analytical method for the glyphosate and its major metabolite the aminomethylphosphonic acid (AMPA) by coupling microfluidics with surface enhanced Raman ... [more ▼]

The goal of this work is to develop a quantitative analytical method for the glyphosate and its major metabolite the aminomethylphosphonic acid (AMPA) by coupling microfluidics with surface enhanced Raman spectroscopy (SERS). This work is divided into 4 axes : (a) bimetallic nanoparticles synthesis in a microreactor, (b) nanoparticles functionnalisation, (c) SERS quantification of glyphosate/AMPA and (d) miniature prototype development composed of axes a to c. The first section aims at the synthesis of bimetallic nanoparticles (Au-Ag, Au-Cu and Ag-Cu) in a microfluidic device. This microfluidic device integrates a first section for the synthesis of monometallic nanoparticles (core) and a second section for the reductive deposition of a second metal (shell). The second axe of this work deals with the functionnalisation of nanoparticles to improve the selectivity of this method for the selected analytes. Two types of functionnalisation are studied : PEGylation (a) with multi-arm PEG ending with -SH and/or (b) with linear heterobifunctionnal PEG. The third axe consists in measuring quantitatively glyphosate and AMPA in different matrices, such as water, urine and fruit juice. Finally, the forth axe deals with the development of a portable detection system to perform on-site analysis. This prototype integrates the microfluidic device for nanoparticles synthesis, their functionnalisation, an injection port followed by a mixing section for the sample and an integrated Raman spectrometer for in-line analysis. [less ▲]

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See detailNonlinear analysis of compliant mechanisms: application to tape springs
Dewalque, Florence ULg; Bruls, Olivier ULg

Poster (2016, July 07)

Brief summary of the mechanical behaviour of tape springs. Main results obtained by the means of finite element models. Description of the experimental set-up and results. See the extended abstract for ... [more ▼]

Brief summary of the mechanical behaviour of tape springs. Main results obtained by the means of finite element models. Description of the experimental set-up and results. See the extended abstract for more details. [less ▲]

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See detailRestricted interests in autism with versus without speech onset delay : the importance of perceptually versus thematically organized interests
Chiodo, Liliane ULg; Majerus, Steve ULg; Eusèbe, Sandrine et al

Poster (2016, July 07)

Objectives : To explore whether autistic adults with vs without speech delay also differ in the perceptual vs thematic nature of their restricted interests.

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See detailDevelopment and optimization of a TD-GC/MS methodology for detection and quantifi cation of furan released in air using of an experimental design.
Alsafra, Zouheir ULg; Scholl, Georges ULg; Romain et al

Poster (2016, July 07)

In the aim of understanding the way in which human is exposed to furan present in the air of an occupational area, an analytical method of Thermal desorption-gas chromatography/Mass spectrometry (TD-GC/MS ... [more ▼]

In the aim of understanding the way in which human is exposed to furan present in the air of an occupational area, an analytical method of Thermal desorption-gas chromatography/Mass spectrometry (TD-GC/MS) has been developed and optimized using a Plackett–Burman experimental design. This method was then used to study the phenomena of diffusion of furan released in air from a contamination source. This source of furan is simply a coffee machine located in a closed controlled room. Results show that furan concentration increases quickly over time after turning on the coffee machine until reaching a maxima. Then it starts to decrease slowly. On the other hand, concentration of furan seems to be identical everywhere in the conditioned room in each moment. [less ▲]

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See detailNovel butanol pretreatment significantly improves delignification and saccharification of different lignocellulosic biomasses
Schmetz, Quentin ULg; Teramura, Hiroshi; Jacquet, Nicolas ULg et al

Poster (2016, July 07)

Organosolv pretreatment using diluted acid and butanol allows the separation of cellulose, hemicelluloses and lignin into three distinct phases. The butanol process has been investigated on six different ... [more ▼]

Organosolv pretreatment using diluted acid and butanol allows the separation of cellulose, hemicelluloses and lignin into three distinct phases. The butanol process has been investigated on six different biomasses: tall fescue, sugarbeet pulp, sugarcane bagasse, beech wood, eucalyptus and Japanese cedar. Dilute acid pretreatment has been performed under similar conditions for comparison. [less ▲]

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See detailEtude de la composition chimique de Pseudotsuga menziesii (Mirb.) Franco et évaluation de l’impact de divers prétraitements lignocellulosiques sur l’extraction de la lignine
Berchem, Thomas ULg; Schmetz, Quentin ULg; Jacquet, Nicolas ULg et al

Poster (2016, July 06)

La raréfaction des ressources fossiles est une certitude à l’heure actuelle. Il est donc primordial de trouver des voies de production plus durables pour des produits de consommation courante. Le ... [more ▼]

La raréfaction des ressources fossiles est une certitude à l’heure actuelle. Il est donc primordial de trouver des voies de production plus durables pour des produits de consommation courante. Le bioraffinage fait partie des solutions envisagées pour substituer les matériaux originaires de la filière pétrochimique. Dans cette optique, ce travail se focalise sur l’extraction et la caractérisation de la lignine à partir d’une biomasse présente en abondance en région Wallonne, Pseudotsuga menziesii (Mirb.) Franco (Douglas). Ce travail vise à montrer l’impact de divers prétraitements lignocellulosiques, tant en terme de rendements et de pureté d’extraction qu’au niveau de la modification de la structure et des propriétés des lignines. Ces différents paramètres sont évalués par des techniques gravimétriques (Klason), chromatographiques (chromatographie d’exclusion stérique) et spectroscopiques (RMN 2D HSQC). Pseudotsuga menziesii (Mirb.) Franco a été préalablement caractérisé par son taux de matière lignocellulosique (cellulose, hémicelluloses, lignine), ainsi que sa teneurs en cendres, en protéines et en extractibles (à l’eau et à l’éthanol). Les lignines natives ont été caractérisées par RMN 2D HSQC. [less ▲]

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See detailOptimisation de la production d’acide furan-2,5-dicarboxylique à partir de déchets verts pour la conception de plastiques bio-basés
Istasse, Thibaut ULg; Jacquet, Nicolas ULg; Richel, Aurore ULg

Poster (2016, July 06)

Afin de trouver des alternatives renouvelables aux produits issus de l’industrie pétrochimique, de nombreuses voies de recherches ont été explorées. Une voie prometteuse est la technologie des dérivés ... [more ▼]

Afin de trouver des alternatives renouvelables aux produits issus de l’industrie pétrochimique, de nombreuses voies de recherches ont été explorées. Une voie prometteuse est la technologie des dérivés furaniques. Parmi ces composés, le 5-hydroxyméthylfurfural (5-HMF) fait partie des molécules plateformes les plus importantes1. Il s’agit d’un produit de dégradation obtenu par déshydratation des hexoses2,3. Le 5-HMF peut servir de base à la conception de nombreuses molécules valorisables comme l’acide furan-2,5-dicarboxylique dont la structure proche de l’acide téréphtalique permet des applications dans la conception de polymères bio-basés3. L’acide furan-2,5-dicarboxylique respecte la législation REACH selon l’European Chemicals Agency4. Un rapport de l’EFSA de 2014 a démontré que cette substance ne posait pas de problème de toxicité lors de son utilisation comme monomère de base dans les plastiques d’emballage pour aliments5. Selon la société Avantium, le FDCA peut être utilisé pour produire un plastique entièrement bio-basé, le polyéthylène furanoate (PEF), qui affiche des performances supérieures à celle du poléthylène téréphtalate (PET) en termes de stabilité thermique, de propriétés mécaniques et de perméabilité aux gaz6. Si le FDCA peut être convertit en de nombreux produits à haute valeur ajoutée, il existe toutefois un frein majeur à son exploitation industrielle : son précurseur, le 5-HMF, n’est pas encore produit en grande quantité1. Ce problème est dû principalement à la déshydratation non sélective des sucres de la biomasse qui aboutit à de nombreux autres produits que le 5-HMF. La première difficulté à surmonter est donc la mise au point d’un procédé permettant de déshydrater de manière efficace et sélective les sucres de la biomasse. Le 5-HMF est également peu stable en milieu acide où il se décompose en acide formique et en acide lévulinique2. L'enjeu du projet de recherche présenté est donc l’optimisation de la production de 5-HMF à partir d’un ou plusieurs types de biomasses dans un premier temps, puis l’optimisation de la conversion du 5-HMF produit en FDCA. Les paramètres à prendre en compte sont notamment les sources de biomasse, l’efficacité des prétraitements concernant l’extraction des sucres, la sélectivité et l’efficacité de la conversion de ces sucres en 5-HMF (système mono- ou biphasique), l’étude de divers catalyseurs, le coût des traitements, etc… [less ▲]

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See detailHigh-temperature and quantitative XRD study of typical Westerwald clays (Germany)
Fontaine, François ULg; Fagel, Nathalie ULg

Poster (2016, July 05)

The Westerwald is one of the largest and oldest clay mining area of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of Devonian ... [more ▼]

The Westerwald is one of the largest and oldest clay mining area of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of Devonian rocks. During the Miocene, intense volcanic activities led to a large basalt cover, protecting the clays from the erosion. The fine fraction is mainly composed of kaolinite and illite, with the possible presence of interstratified I S. Other minerals such as quartz, feldspars, hematite, goethite or anatase are present in variable concentrations. Four typical Westerwald clays were chosen for this study: kaolinite-rich clay, kaolinite-illite clay, a red and a yellow firing clays. The first goal is to perform quantitative XRD using two different methods and to compare them: reference intensity ratio (RIR) and Rietveld (using Topas and BGMN). The second goal is the study of those samples using high-temperature XRD (HTXRD). The samples were heated up to 1250°C and a XRD pattern was obtained in situ every 100°C. The results show the temperatures of vitrification and formation of mullite and cristobalite varying from one sample to another, which is mainly linked to their flux concentration. [less ▲]

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See detailIdentifying wheat varieties with low acrylamide potential
Lecart, Brieuc ULg; Jacquet, Nicolas ULg; Anseeuw, Laurent et al

Poster (2016, July 05)

Maillard reactions are responsible for the formation of many compounds in food that have been baked at temperatures above 120°C1. Some of these compounds are sought for their contribution to the ... [more ▼]

Maillard reactions are responsible for the formation of many compounds in food that have been baked at temperatures above 120°C1. Some of these compounds are sought for their contribution to the organoleptic qualities of food but others, such as acrylamide, have been identified since 1986 as reprotoxic, genotoxic and carcinogenic in animals2. Synthesized from a chain reaction between free sugars and free asparagine, acrylamide has been found in many food such as products prepared from wheat flour1,3,4. The correlation between the amount of free sugars and free asparagine in raw food with the acrylamide content in the baked food has been well documented5. For this reason we compared the levels of 15 wheat varieties and identified wheat varieties with significantly lower level (=0.05) in acrylamide precursors. Those varieties could therefore be used preferentially in products intended for food. [less ▲]

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See detailPIXE-PIGE analysis of Early Medieval Glass Artefacts at IPNAS cyclotron external beam line
Chene, Grégoire ULg; Van Wersch, Line ULg; Biron, Isabelle et al

Poster (2016, July 05)

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See detailL’intégration d’indicateurs biologiques dans un réseau de surveillance des sols afin d’améliorer le diagnostic de la qualité du sol – une étude de cas dans le sud de la Belgique (Wallonie)
Krüger, Inken ULg; Chartin, Caroline; van Wesemael, Bas et al

Poster (2016, July 05)

Les organismes du sol et leurs activités sont essentiels pour le fonctionnement de l’écosystème du sol et ils peuvent donc servir comme indicateurs de la qualité du sol. Des efforts ont récemment été ... [more ▼]

Les organismes du sol et leurs activités sont essentiels pour le fonctionnement de l’écosystème du sol et ils peuvent donc servir comme indicateurs de la qualité du sol. Des efforts ont récemment été menés pour intégrer les indicateurs biologiques de la qualité du sol dans les réseaux de surveillance régionaux/nationaux. Le but de cette étude était de déterminer des gammes de valeurs pour six indicateurs biologiques et deux quotients éco-physiologiques pour les sols agricoles. La respiration potentielle, la biomasse microbienne (carbone et azote), la minéralisation nette de l’azote, la diversité métabolique des bactéries du sol, l’abondance des vers de terre, le quotient microbien et le quotient métabolique ont été mesurés dans 60 sites dans des régions agricoles contrastées (différents types de sol et climat) et différentes utilisations de sol (prairies et cultures) sélectionnés d’un réseau de surveillance du carbone organique du sol (CARBOSOL). Les liens entre indicateurs biologiques et paramètres chimiques (le pH du sol, carbone organique total, soluble, labile et stable) sont analysés. Quatre des six indicateurs biologiques sélectionnés (respiration potentielle, biomasse microbienne (carbone et azote) et diversité métabolique des bactéries du sol) sont significativement plus élevés sous prairies que sous cultures. Les gammes de valeurs sont plus larges sous prairies que sous cultures. Les indicateurs biologiques sélectionnés ne sont pas significativement influencés par la région agricole. Les meilleures corrélations avec les paramètres chimiques ont été trouvées pour la respiration potentielle et la biomasse microbienne (carbone et azote). L’étude définit des gammes de valeurs pour les sols agricoles à l’échelle régionale (Wallonie) séparées par utilisation de sol (prairies et cultures) et présente une base solide pour l’établissement d’un réseau de surveillance de la qualité biologique du sol. [less ▲]

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See detailProgramme de soutien aux aidants de patients présentant la maladie d’Alzheimer : une étude de cas
Clesse, Audrey ULg; Missotten, Pierre ULg; Adam, Stéphane ULg

Poster (2016, July 05)

Il est largement reconnu que vivre au jour le jour avec un proche atteint de la maladie d’Alzheimer est une situation particulièrement éprouvante. La charge générée par cette maladie peut menée à des ... [more ▼]

Il est largement reconnu que vivre au jour le jour avec un proche atteint de la maladie d’Alzheimer est une situation particulièrement éprouvante. La charge générée par cette maladie peut menée à des états de fatigue psychologiques et physiques, voir au burnout, pour l’aidant. Plusieurs études sur la santé des aidants prenant en charge un proche dément ont montré qu’ils constituent, en comparaison aux personnes s’occupant d’un individu âgé non dément, une population à risque, notamment en termes de symptômes dépressifs, détresse psychologique ou de problèmes de santé. Ces constats alarmants justifient la mise en place de programmes de soutien visant à offrir un suivi thérapeutique aux personnes ayant un conjoint ou un parent présentant une démence de type Alzheimer. Nous présentons l’étude de cas de Mme C.G., fille d’une patiente âgée de 79 ans, ayant suivi le programme de soutien développé par Adam et al. (2009), basé sur l’approche de gestion du stress qui suggère l’utilisation de stratégies d’ajustement centrées sur la résolution de problèmes. Avant et après l’intervention, Mme C.G. a répondu à différents questionnaires examinant sa santé psychologique (MBI, BDI-II, STAI, etc.), sa manière de gérer la maladie de son parent (WCC, CAMI, SCQ, etc.) et l’état général de la patiente (ADRQL, IADL, NPI). La comparaison pré et post-intervention apporte des éléments positifs, notamment concernant l’amélioration de la qualité de vie de l’aidante, de son sentiment de compétence et d’efficacité à gérer la maladie au quotidien. Concernant le burnout, qui était la priorité de cette intervention, nous constatons que l’épuisement émotionnel de l’aidante tend à diminuer au cours des séances de counseling. Un autre constat particulièrement important concerne les changements familiaux opérés tout au long de la thérapie ; ce qui pose question quant à la réorganisation de la dynamique familiale. Ces résultats positifs démontrent l’importance de développer des programmes d’aide aux aidants grâce à une approche clinique globale et holistique de la situation, étant donné les composantes neuropsychologiques, cognitives et systémiques impliquées. [less ▲]

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See detailFast separation of triterpenoid saponins using supercritical fluid chromatography coupled with single quadrupole mass spectrometry
Huang, Yang ULg

Poster (2016, July 03)

Triterpenoid saponins (TSs) are the most important components of some traditional Chinese medicines (TCMs) and have exhibited valuable pharmacological properties[1-2]. Supercritical fluid chromatography ... [more ▼]

Triterpenoid saponins (TSs) are the most important components of some traditional Chinese medicines (TCMs) and have exhibited valuable pharmacological properties[1-2]. Supercritical fluid chromatography (SFC), considered as a green separation technique, is a potential alternative to LC for the analysis of TSs. However, the application of SFC-MS to the analysis of TSs has not yet been reported. In the present study, rapid and efficient SFC-MS methods were developed for the first time for the separation of both TSs standards (kudinosides and ginsenosides) and TSs from natural product extracts. Moreover, a comprehensive comparison between LC-MS and SFC-MS with respect to selectivity and running time was carried out using a mixture of TSs as test sample. [less ▲]

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See detailApplication of NIR hyperspectral imaging combined to chemometrics to assess the impact of tillage on the root system development of a winter wheat crop
Fraipont, Guillaume ULg; Eylenbosch, Damien ULg; Baeten, Vincent et al

Poster (2016, July)

This poster presents de results of a study of the influence of tillage on the root development of a winter wheat crop. The originality of this research lies in the application of an innovative root ... [more ▼]

This poster presents de results of a study of the influence of tillage on the root development of a winter wheat crop. The originality of this research lies in the application of an innovative root quantification method based on the near infrared hyperspectral imaging. [less ▲]

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See detailMagnetocapillary self-assemblies: Swimming and micromanipulation
Grosjean, Galien ULg; Hubert, Maxime ULg; Lagubeau, Guillaume et al

Poster (2016, July)

Floating magnetic particles can self-assemble into structures, by a combination of a magnetic dipole-dipole interaction and an attraction due to the interfacial deformation. These structures are ... [more ▼]

Floating magnetic particles can self-assemble into structures, by a combination of a magnetic dipole-dipole interaction and an attraction due to the interfacial deformation. These structures are periodically deformed in a non reciprocal way using magnetic fields, which leads to controllable low Reynolds number locomotion. Such microswimmers provide a basis for micromanipulation applications such as transport of micro-objects, local mixing of fluids or surface cleaning. [less ▲]

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See detailDroplet manipulation on fiber networks
Weyer, Floriane ULg; Pan, Zhao; Truscott, Tadd et al

Poster (2016, July)

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See detailHeavy methane to explain the unexplained recent methane growth ?
Bader, Whitney ULg; Strong, Kim; Walker, Kaley

Poster (2016, July)

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more ... [more ▼]

Methane (CH4) is the second most important greenhouse gas emitted by human activities in the Earth’s atmosphere. Although it is roughly 200 times less abundant than carbon dioxide, it is a 28 times more potent greenhouse gas. Approximately one fifth of the changes in the Earth’s balance energy caused by human-linked greenhouse gases since the beginning of industrialization (~1750) is due to methane. Methane is emitted by both natural sources and human activities. Indeed, methane can be emitted to the atmosphere through coal mining, oil and gas exploitation, rice cultures, domestic ruminant animals, biomass burning, waste management, wetlands, termites, methane hydrates and ocean. In the atmosphere, methane is mainly destroyed by the radical hydroxyl, also called the detergent of the atmosphere, and therefore plays a major role on the oxidizing capacity of the atmosphere. Since the beginning of the industrialization, atmospheric methane concentrations have increased by 260% to reach 1824 pbb in 2013. From the 1980s until the beginning of the 1990s, atmospheric methane was significantly on the rise, then stabilized during 1999-2006 to rise again afterwards. To this day, the source or sink responsible of this latter increase remains unexplained. Through each emission process, heavy molecules of methane (with one additional neutron either on a carbon or on one hydrogen atom) are emitted along methane (12CH4). The main heavy molecules of methane, called isotopologues (13CH4 and CH3D), are respectively ~110 and ~60 000 times less abundant than methane. Despite their small abundances, they give crucial information on the concentration of methane in the atmosphere and its evolution. Indeed, both isotopologues are emitted with specific emission ratio depending on the emission sources. Determining isotopic ratio of atmospheric methane is therefore a unique tracer of its budget. While the non-monotonous trend of methane is subject of an extensive number of studies, to our knowledge, no study of the isotopic ratio of methane derived from ground-based solar observations has been published to date. Measurements of heavy methane from Fourier Transform InfraRed spectra recorded with state of the art spectrometers installed at Eureka [Arctic, Canada] and Toronto [Ontario, Canada] along with analysis of observations collected by a portable instrument [Portable Atmospheric Research Interferometric Spectrometer for the Infrared, PARIS-IR], installed at Eureka will help fill this gap. Indeed, the produced time series, compared with the corresponding satellite observations (ACE-FTS) products will ease data interpretation and contribute to a global view of the question of isotopologues. [less ▲]

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See detailPaleoenvironmental implications in the dried lake sediments (Amik Lake, Southern Turkey)
El Ouahabi, Meriam ULg; Hubert, Aurelia ULg; Vander Auwera, Jacqueline ULg et al

Poster (2016, July)

The Amik Basin in the Eastern Mediterranean region has been continuously inhabited since 6000 – 7000 BC. The study focuses on the sedimentary record of the Amik Lake located in the central part of the ... [more ▼]

The Amik Basin in the Eastern Mediterranean region has been continuously inhabited since 6000 – 7000 BC. The study focuses on the sedimentary record of the Amik Lake located in the central part of the basin. Our objective is to constrain major paleo-environmental changes in the area over the last 4000 years and to unravel possible human impacts on the sedimentation. A diverse array of complementary methods was applied on the 6 m long record. Mineralogical (XRD), and geochemical (XRF) analyses were performed. The age of the record is constrained combining radionuclide and radiocarbon dating. A high sedimentation rate of 0.12 cm/yr was inferred at the studied site. The 4000 years (since ~1800 BC) long record shows that significant fluctuations of the lake level and the riverine system inflow into the Amik Lake occurred. The Late Bronze lowstand led to punctual dryings of the lake at the end of the Bronze/Iron Age transition. At that time, the rivers yielded a large terrigenous input linked to strong soil erosion related mainly to deforestation and exploitation of mineral resources. During the Roman and later periods, upland soils were partly depleted and the riverine system completely transformed by channelization (anthropic) that led to a marshification of the Amik Basin [1]. Chemical and mineralogical composition of sediments is quite diversified reflecting the significant geological variation of drainage basins. Periods with strong aggradation linked to major increase in erosion were identified and characterized by high amount of Cr, Ni and Zr. Levels relatively rich in fluorite, richterite, enstatite, hornblende and chrysotile are a result of the erosion of the ophiolitic rocks from the surrounding Amanos Mountains. These levels are interpreted as periods of relatively high physical erosion, while more humid periods led to more intensive weathering. Consequently, the dominance of kaolinite, muscovite/illite and talc indicates a climate with contrasting seasons. During the most recent period a marked increase in terrigenous minerals associated with a rise in dolomite indicates ungoing erosion as well as the drying-out of the lake. [1] T.J. Wilkinson, L. Rayne, Water History, 2, 115-144 (2010). [less ▲]

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See detailGeochemistry and mineralogy approaches to characterize brick and its lake sediments sources: Antioch Roman City (Southern Turkey)
El Ouahabi, Meriam ULg; Hubert, Aurelia ULg; Benjelloun, Yacine et al

Poster (2016, July)

The Roman aqueduct of Antioch-on-the-Orontes (Southern Turkey) is situated close to the Antioch city. This last is located near the Amik Lake (Lake of Antioch) and close to the junction between the active ... [more ▼]

The Roman aqueduct of Antioch-on-the-Orontes (Southern Turkey) is situated close to the Antioch city. This last is located near the Amik Lake (Lake of Antioch) and close to the junction between the active Dead Sea fault and the East Anatolian fault. During the Roman period, the Amik Plain was more densely occupied than at any time in its history [1]. The study focuses on the bricks and the lake sediments characterization in order to determine the source area as well as the technical production used at this period. For this purpose, several bricks were sampled on different parts of the city's aqueducts. Furthermore, a core of about 6 m of sediments was also collected from the dried Amik Lake. The bricks were characterized through a mineralogical (XRD) and chemical (PIXE-PIGE) approaches. Unfired clay fraction remained as inclusion in the brick was separated and then analysed using XRD. Geochemical composition and clay mineralogy were performed on the raw sediments from the Amik Lake in order to compare the source area. Technological test will be performed on the raw clay sediments from the Amik Lake in the purpose to understand the production techniques used at this time. The age of the brick production was previously dated to the Roman Period [2]. The synthesis of all the data attested the Amik Lake sediment as the raw material for the bricks of the aqueduct. Clay mineral composition from the Roman period deposited in the lake is smectite, illite, kaolinite and small amount of mixed-layer clays. The similar clays composition is found in the remained clays on the brick used for the aqueduct construction. Fast and heterogeneous firing practice characterized the manufacturing of these materials due to the rapid need for the materials during the post-seismic repairs after earthquakes that are mentioned in historical written works. [1] J. Casana, Geomorphology, 101, 429-442 (2008) [2] Y. Benjelloun, J. de Sigoyer, J. Carlut, A. Hubert-Ferrari, H. Dessales, H. Pamir, V. Karabacak, Comptes Rendus Geoscience, 347, 170-180 (2015) [less ▲]

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See detailPolyurethane coatings in 20th century outdoor painted sculptures: discrimination of main systems by means of Py-GC-MS and ATR-FTIR
Defeyt, Catherine ULg; Schilling, Michael; Langenbacher, Julia et al

Poster (2016, July)

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See detailInternal structures of clusters in driven granular gas
Noirhomme, Martial ULg

Poster (2016, July)

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See detailCoherent backscattering in the Fock space of Bose- and Fermi-Hubbard systems
Engl, Thomas; Dujardin, Julien; Tisserond, Emilie et al

Poster (2016, July)

Coherent backscattering generally refers to a significant and robust enhancement of the average backscattering probability of a wave within a disordered medium, which from a semiclassical point of view ... [more ▼]

Coherent backscattering generally refers to a significant and robust enhancement of the average backscattering probability of a wave within a disordered medium, which from a semiclassical point of view arises due to the constructive interference between backscattered trajectories and their time-reversed counterparts. We recently investigated the manifestation of this wave interference phenomenon in the Fock space of a disordered Bose-Hubbard system of finite extent [1], which can potentially be realized using ultracold bosonic atoms within optical lattices. Preparing the atoms in a well-defined Fock state of the lattice and letting the system evolve for a finite time will, for suitable parameters of the system and upon some disorder average over random on-site energies of the lattice, generally give rise to an equidistribution of the occupation probability within the energy shell of the Fock space that corresponds to the initial energy of the system, in accordance with the quantum microcanonical ensemble. We find, however, that the initial state is twice as often encountered as other Fock states with comparable total energy, which is a consequence of coherent backscattering [1]. Most recently, we showed that this phenomenon also arises in spin 1/2 Fermi-Hubbard rings that involve Rashba hopping terms (which combine inter-site hoppings with spin flips and arise from spin-orbit coupling), for which a newly developed semiclassical theory [2] correctly predicts a coherent enhancement of the occupation probabilities of the initial state and its spin-flipped counterpart. Moreover, performing a global spin flip within this Fermi-Hubbard system will give rise to significant spin echo peaks on those two Fock states, which is again a consequence of quantum many-body interference [3]. The semiclassical predictions of these enhancements and peaks are found to be in very good agreement with numerical findings obtained from the exact quantum time evolution within this Fermi-Hubbard system. [1] T. Engl, J. Dujardin, A. Argüelles, P. Schlagheck, K. Richter, and J. D. Urbina, Phys. Rev. Lett. 112, 140403 (2014). [2] T. Engl, P. Plößl, J. D. Urbina, and K. Richter, Theoretical Chemistry Accounts 133, 1563 (2014). [3] T. Engl, J. D. Urbina, and K. Richter, arXiv:1409.5684. [less ▲]

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See detailSolo vs. duet in different virtual rooms: On the consistency of singing quality across conditions
Fischinger, Timo; Kreutz, Gunter; Larrouy, Pauline ULg

Poster (2016, July)

Previous research on vocal pitch accuracy revealed insights into the fundamentals of singing. However, most of the research on singing focused on the analysis of single voices, whereas few aYempts have ... [more ▼]

Previous research on vocal pitch accuracy revealed insights into the fundamentals of singing. However, most of the research on singing focused on the analysis of single voices, whereas few aYempts have been made to tackle the challenge of analyzing mulTtrack recordings of singing ensembles. In addiTon, singers have to adjust their way of singing with respect to a given venue’s acousTcal environment (e.g., small room vs. a comparaTvely large space like a church). If it is common that musical performances are greatly influenced by room acousTcs, studies on the effects of room acousTcal features during ensemble singing are rare. In order to invesTgate singing performances across various condiTons, we manipulated the singing condiTon (unison, canon, solo) as well as the acousTcal feedback by applying diverging virtual rooms. Three duets with female singers (N = 6) were asked to sing three different melodies using headset microphones to record each singer separately. Recordings took place in the communicaTon acousTc simulator (CAS) at the House of Hearing (Oldenburg, Germany) to be able to provide different simulated acousTcal spaces (i.e., cathedral, classroom, and dry condiTon) to the singers. ObjecTve measures were performed on each recording and confirmed that the singers sang the melodies with high precision (small pitch interval deviaTons) hardly affected by singing condiTons or by the type of acousTcal feedback. However, the singers tended to driH (larger deviaTons of the tonal center) when singing in canon compared to solo and unison singing. Overall, the analysis of the pitch accuracy showed a general effect of condiTon (i.e., unison, canon, solo), but no general effect of acousTcal feedback and no interacTon between the two variables under study. [less ▲]

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See detailPassive flutter suppression using a nonlinear tuned vibration absorber
Verstraelen, Edouard ULg; Gourc, Etienne ULg; Kerschen, Gaëtan ULg et al

Poster (2016, July)

A recent study showed that the addition of a linear tuned vibration absorber could increase the flutter speed of a rigid wing with pitch and flap degrees of freedom by about 35%. However, the absorber was ... [more ▼]

A recent study showed that the addition of a linear tuned vibration absorber could increase the flutter speed of a rigid wing with pitch and flap degrees of freedom by about 35%. However, the absorber was turning the initial super-critical bifurcation into a sub-critical one. This work shows numerically that adding a nonlinear restoring force to the absorber can restore the su- percritical behaviour of the bifurcation and further reduce the post-instability limit cycle amplitude. [less ▲]

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See detailInterspecific variation of warning calls in piranhas: comparative analysis
Mélotte, Geoffrey ULg; Michel, Christian ULg; Vigouroux, Régis et al

Poster (2016, July)

Fish sounds are often considered as species-specific with unique temporal and spectral features. Differences between acoustic signals of closely related species could be considered as pre-zygotic barrier ... [more ▼]

Fish sounds are often considered as species-specific with unique temporal and spectral features. Differences between acoustic signals of closely related species could be considered as pre-zygotic barrier and could be related to the evolutionary history of the species. In the present study, sounds were recorded and compared in eight piranha species (Serrasalmus elongatus, Serrasalmus marginatus, Serrasalmus compressus, Serrasalmus manueli, Serrasalmus spilopleura, Serrasalmus rhombeus, Serrasalmus eigenmanni and Pygocentrus nattereri) in order to evaluate the potential role of acoustic communication as a driving force in the clade diversification. The same kind of sound-producing mechanism was found in all the species: sonic muscles originate on vertebrae and attach to a tendon surrounding ventrally the bladder. Contractions of the sound-producing muscles force swimbladder vibration. Having the same kind of sound-producing mechanism, the calling features of the eight piranha species show logically many common characteristics. In all the species, the calls are harmonic sounds composed of several pulses without inter-pulse interval. It was possible to discern species-specific sounds, but the differences among species could be, in part, explained by the size. Only the sounds of S. elongatus and S. manueli are really distinguishable from the other species. Serrasalmus elongatus differed by having a higher number of pulses and high-pitched fundamental frequency, whereas S. manueli differed by having long pulse periods and a low fundamental frequency. In the framework of this study, acoustic communication cannot be considered as the main driving force in the diversification process of piranhas. Behavioral studies are however needed to clearly understand the eventual role of the calls during the spawning events. [less ▲]

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See detailChallenge testing with Brochothrix thermosphacta on minced pork meat shows interest to couple metagenetics to metabolomics to study food spoilage
Baré, Ghislain ULg; Cauchie, Emilie ULg; Leenders, Justine ULg et al

Poster (2016, July)

The spoilage of perishable foods is mainly caused by bacterial activity. The risk of unwanted bacterial growth is particularly high in the minced pork meat. In this work, the natural microbial ... [more ▼]

The spoilage of perishable foods is mainly caused by bacterial activity. The risk of unwanted bacterial growth is particularly high in the minced pork meat. In this work, the natural microbial contaminants of the minced pork meat were followed by 16S ribosomal DNA deep sequencing (metagenetics) during aging tests at different temperatures. Brochothrix thermosphacta MM008 strain was selected as one of the main contaminants responsible for the spoilage of the meat. Minced pork meat previously sterilized by gamma irradiation was inoculated with B. thermosphacta MM008 for challenge tests measuring growth and then incubated at different temperatures. Minced meat samples were taken and analyzed by H-NMR 1D at time 0 and at final time (from 14 to 19 days, depending on the incubation temperature). Orthogonal partial least square discriminant analysis (OPLS-DA) showed that samples, regardless of the incubation temperature, could be splitted into 3 groups according to their spectral profile: 1) samples taken at time 0, 2) samples inoculated with B. thermosphacta and taken at final time, 3) samples uninoculated, taken at final time. From the analysis of the metabolomics data, higher concentrations of glycerol, glucose, taurine, lactate, carnitine, betaine and glycine were identified in the samples of uninoculated minced pork meat and an increased production of creatine, acetate and acetone was found in the samples of minced pork meat inoculated with B. thermosphacta MM008. These observations showed that -omics technologies (metagenetics and metabolomics) could be used conclusively to study microbial spoilage of minced pork meat. [less ▲]

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See detailObservational signatures of past mass-exchange episodes in massive binaries : The cases of LSS 3074 and HD 17505
Raucq, Françoise ULg; Rauw, Grégor ULg; Gosset, Eric ULg et al

Poster (2016, July)

Mass and angular momentum exchanges through Roche Lobe Overflow interactions within close massive binaries are known to play an important role in the subsequent evolution of the components of such systems ... [more ▼]

Mass and angular momentum exchanges through Roche Lobe Overflow interactions within close massive binaries are known to play an important role in the subsequent evolution of the components of such systems, and produce several observational signatures, such as asynchronous rotation and altered chemical compositions, that remain once the stars detach again. We have started to investigate these effects in a sample of massive O-star binaries that are thought to have previously experienced a Case A Roche Lobe Overflow episode. Using phase-resolved spectroscopy, we perform the disentangling of the optical spectra of the two stars. The reconstructed primary and secondary spectra re then analysed with the CMFGEN model atmosphere code to determine stellar parameters such as the effective temperatures, surface gravities and rotational velocities, and to constrain the chemical composition of the components. In this contribution, we present the results of our analyses of LSS 3074 (O5.5I + O6.5-7I, P = 2.1852 days), together with the analyses of its photometric lightcurve and orbital solution. We also present the first results of our analyses of the triple system HD17505 ([O7.5V + O7.5V, P = 8.57 days] + O6.5III). [less ▲]

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See detailA Frasnian palynological assemblage from the NE Iberian Chain
Rial, Gonzalo; Cascales-Miñana, Borja ULg; Gerrienne, Philippe ULg et al

Poster (2016, July)

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See detailNew fossil evidence of Acrostichum from the Iberian Peninsula reveals the pioneering behaviour of this fern
Moreno-Domínguez, Rafael; Cascales-Miñana, Borja ULg; Diez, José B.

Poster (2016, July)

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See detailPlant-insect interactions from the Late Oligocene Ebro Basin (Estadilla, Huesca, Spain): A preliminary report
Moreno-Domínguez, Rafael; Cascales-Miñana, Borja ULg; Santos, A. A. et al

Poster (2016, July)

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See detailStudy of Mezoneuron benthamianum, a plant traditionally used against malaria in Guinea
Tchinda Tiabou, Alembert ULg; Loua, Jean; Esters, Virginie ULg et al

Poster (2016, July)

Despite some improvements in malaria control, this parasitic disease remains a major public health problem in many African countries, causing about 400 000 deaths/year through the continent, mainly by ... [more ▼]

Despite some improvements in malaria control, this parasitic disease remains a major public health problem in many African countries, causing about 400 000 deaths/year through the continent, mainly by children under the age of five (WHO, 2015). In Guinea, the leaves of Mezoneuron benthamianum Baill. are traditionally used to treat malaria (Traore et al., 2013) and showed a good antiplasmodial activity in an antiprotozoal in vitro screening (Traore et al., 2014), as well as promising results in a preliminary small-scale ethnomedical study (unpublished data), encouraging us to continue the study of this plant. The aim of this work was to evaluate the activity of M. benthamianum leaves extracts against P. falciparum using an in vitro test model (p-LDH assay) and to undertake a bio-guided fractionation to identify the compounds responsible for the activity. Hydroethanolic extracts (70% v/v) of M. benthamianum leaves showed a moderate in vitro activity against P. falciparum 3D7, with IC50 = 22.5 – 32.6 µg/ml, depending on the batch; while a dark precipitate formed during ethanol evaporation showed higher activity (IC50 = 6,5µg/ml). The bioguided fractionation was performed on this most active fraction and allowed the isolation of three diterpens, two flavonoids, resveratrol, gallic acid and its ethylester, β-sitosterol glucoside and pheophorbide derivatives. The active compounds belong to several phytochemical classes, including flavonoids, pheophorbide and gallic acid derivatives, contributing together to the global antiplasmodial activity of the hydroalcoholic extract against P. falciparum parasite. This study gives some concrete evidence to support the ethnopharmacological use of Mezoneuron benthamianum leaves extract in the management of malaria. The active compounds can be further studied for their antiplasmodial potential, as well as their suitability to be used as quality markers for the standardization of this herbal drug from the Guinean traditional pharmacopeia. [less ▲]

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See detailLaser Ultrasound for NDT: investigation of the generation beam shape
Languy, Fabian ULg; Perrard, Aurélie; Vandenrijt, Jean-François ULg et al

Poster (2016, July)

Usually laser ultrasonic systems use an infrared laser operating at 10 µm to generate the ultrasound in CFRP objects. However this system suffer from an important drawback: optical fiber cannot be used to ... [more ▼]

Usually laser ultrasonic systems use an infrared laser operating at 10 µm to generate the ultrasound in CFRP objects. However this system suffer from an important drawback: optical fiber cannot be used to transport the high energy beam from the laser output to the target which limits the flexibility of the system to investigated complex shaped objects. To overcome this issue, visible light can be used to generate ultrasound. In our case we use a fiber-coupled laser operating at 532 nm. The output end of the optical fiber is placed on an industrial robot arm. The investigated object remains stationary while the optical fiber mounted on the robot arm scan the object. This system offers large flexibility but laser generation at 532 nm is known to be less efficient than CO 2 system emitting at 10 µm. Increasing the visible pulse power is one of the options but optics and CRFF object will be damaged before the same echo level as CO2 generation can be obtained. An alternative solution consists in the investigation of the generation beam size and shape. We recently developed an optical design composed of an axicon lens able to generate annular beam. The diameter of the beam can be adapted. If the axicon lens is removed the optical system provides a disk whose diameter can also be adapted onto the investigated object. Ray-traycing simulations performed with ASAP and experimental beam profile investigated with a beam profiler show good agreement between theoretical and experimental optical design. An experimental comparison between ring and disk shapes will be presented. The comparisons take into account the beam diameter and the beam intensity but also the effect of the angle of incidence will be presented. [less ▲]

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See detailHeavy metals resisting gravity in white dwarfs ?
Rauch, T.; Gamrath, S.; Quinet, Pascal ULg et al

Poster (2016, July)

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See detailInfluence of the plasma environment on K-line emission in He-, Li-, Ne-, Na-, Ar- and K-like iron ions using a Debye-Hückel model
Deprince, J.; Fritzsche, S.; Kallman, T. et al

Poster (2016, July)

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See detailMCDHF calculations of isotope shifts of even-parity fine-structure levels in neutral osmium
Palmeri, P.; Quinet, Pascal ULg; Bouazza, S.

Poster (2016, July)

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See detailGirls and Math Careers Expectations: Influence of Teacher Support and Motivational Variables
Jaegers, Doriane ULg; Lafontaine, Dominique ULg

Poster (2016, July)

Drawing on the expectancy-value theory, the three basic dimensions of instructional quality and the self-determination theory, this study examines the relation between teacher support, motivational ... [more ▼]

Drawing on the expectancy-value theory, the three basic dimensions of instructional quality and the self-determination theory, this study examines the relation between teacher support, motivational variables, course enrollment and career expectations in the domain of math. Gender differences are also investigated. Teacher support is seen as the fulfilment of the need of relatedness which is defined by the affective and academic quality of the teacher-student relationship. [less ▲]

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See detailSmart co-phasing system for segmented mirror telescopes
Simar, Juan Felipe ULg; Stockman, Yvan ULg; Surdej, Jean ULg

Poster (2016, June 30)

One of the main challenges in space observations is to observe always fainter and more compact objects. This can be achieved by increasing the telescope diameters. So, increasing the primary mirror ... [more ▼]

One of the main challenges in space observations is to observe always fainter and more compact objects. This can be achieved by increasing the telescope diameters. So, increasing the primary mirror diameters of the telescopes is the challenge solution but it is technically impossible to manufacture monolithic mirrors larger than 10m in diameter. The use of segmented mirrors thus becomes mandatory. This paper describes the results of a light co-phasing setup mounted in laboratory. This setup is able to correct a piston from 200μm to 15 nm based on coarse (200μm to 300nm) and fine (300nm to 15nm) measurement methods. Both measurements are then chained in a feedback system in order to completely co-phase and keep the segments aligned. [less ▲]

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See detailUnveiling new stellar companions from the EXOZODI survey : follow up
Marion, Lindsay ULg; Absil, Olivier ULg; Ertel, Steve et al

Poster (2016, June 30)

In 2012, we have conducted a survey of nearby main sequence stars with VLTI/PIONIER to search for the presence of circumstellar dust. We focused on the use of the closure phases and the square ... [more ▼]

In 2012, we have conducted a survey of nearby main sequence stars with VLTI/PIONIER to search for the presence of circumstellar dust. We focused on the use of the closure phases and the square visibilities in a combined way to search for faint companions around the whole sample. In this process, we found four new stellar companions, for which we conducted follow-up observations in 2014. This follow up allows us to confirm the four detections, and to detect another new companion. Only the case of HD202730 remains ambiguous. [less ▲]

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See detailMerging carbon dioxide utilisation, bioresources and CO2-based process for sustainable low carbon footprints polyurethanes
Alves, Margot ULg; Grignard, Bruno ULg; Gennen, Sandro ULg et al

Poster (2016, June 29)

Making plastics more sustainable by valorizing waste CO2 as a cheap, inexhaustible and renewable feedstock is an early stage technology with strong innovation potential that imposes itself as a strategic ... [more ▼]

Making plastics more sustainable by valorizing waste CO2 as a cheap, inexhaustible and renewable feedstock is an early stage technology with strong innovation potential that imposes itself as a strategic driver for developing future low carbon footprints materials and technologies. With a global production estimated to 18 million tons for 2016, polyurethane (PU) is one of the most important polymers in our everyday life with applications in automotive, in building and construction, in coating, in the medical field, as flexible and rigid foams for thermal and/or acoustic insulation. Industrially, PU is produced by step-growth polymerization between di- or polyisocyanates and di- or polyols. However, isocyanates are extremely toxic compounds and made from even more toxic and explosive phosgene. Prolonged exposure to isocyanates vapour results in serious health damages such as skin irritation, asthma or DNA mutation whereas phosgene causes death. Because of the toxicity issues of these compounds associated to drastic changes in the REACH regulations limiting/banning the use of isocyanates, there is a need today to develop new greener and safer alternatives to produce PU. Valorising CO2 as C1 feedstock for producing precursors entering in the synthesis of polyurethanes by a non-isocyanate route (NIPU) is a promising route to solve this challenge the polyurethane sector is facing. Through its global objective focussing on the synthesis of isocyanate-free low carbon footprint foamed materials for thermal insulation this research highlights benefits of merging bio-resources with carbon dioxide transformation and “physical” utilization. The success of the project relies on 3 key steps involving: i) The synthesis of bio- and CO2-sourced cyclic carbonates using new highly efficient organocatalysts: Due to the low reactivity of CO2 versus epoxides, addition of catalysts in the reaction medium is necessary. If lot of catalysts have been developed, their use generally suffers from some drawbacks. Indeed, most of the metal-based catalysts are highly sensitive to hydrolysis and oxidation or/and poorly selective and additionally, some of them are toxic whereas less/non-toxic and eco-friendly organocatalysts such as ionic liquids and halide salts are generally only efficient at very high temperature and pressure, so favouring the decomposition of catalyst. To overcome these limitations, we developed a new highly-efficient bicomponent homogeneous organocatalyst that showed unexpected catalytic activity for the fast (within a few minutes) and selective addition of CO2 onto model epoxides and epoxidized vegetable oils under solvent-free and mild experimental conditions. The use of this powerful dual organocatalyst was further extended to the first organocatalytic coupling of CO2 with less reactive oxetanes to produce hydroxyl telechelic oligocarbonate entering the synthesis of CO2-sourced conventional PUs. ii) The synthesis of sustainable non-isocyanate polyurethanes: Sustainable NIPUs were produced by step-growth polymerization between the so-produced bio- and CO2-sourced cyclic carbonates and biosourced amino-telechelic comonomers derived from linseed fatty acids according to a process compatible with existing industrial infrastructures (extrusion). iii) The foaming of NIPUs: Sustainable foams with thermal insulation were produced by the supercritical CO2 assisted foaming technology. Due to its solubility in polymers, CO2 can replace conventional flammable VOCs and ozone depletion chemical or physical blowing agents such as diazo compounds, hydrocarbons (pentane, isopentane…) or inert gases (nitrogen…) to produce (ultra)lightweight microcellular foams. By finely choosing the CO2 impregnation and the foaming conditions, foams with a thermal conductivity as low as 0.052 Wm-1K-1 were produced. Our study shows that CO2 is not only sequestered in the material for long-term application, but is also valorized as a blowing agent in the production of sustainable thermally insulating NIPU foams. Such low carbon footprints materials will contribute to energy conservation and savings by reducing CO2 emissions [less ▲]

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See detailExploring potentialities of RanbP2-type Zinc Fingers in RNA-binding proteins design
De Franco, Simona ULg; Vandenameele, Julie ULg; Galleni, Moreno ULg et al

Poster (2016, June 29)

Transcriptomes consist of several classes of RNAs, whose roles are central to innumerable biological processes as well as diseases. These observations justify the increasing interest in the engineering of ... [more ▼]

Transcriptomes consist of several classes of RNAs, whose roles are central to innumerable biological processes as well as diseases. These observations justify the increasing interest in the engineering of functionalized RNA-binding proteins (RBPs) to specifically manipulate RNA function. In this context, the RanBP2-type Zinc Finger (ZF) domain emerged as a suitable scaffold for single-stranded RBPs design. The present study aimed to identify the sequence-specificity of several naturally occurring RanBP2-type ZFs by in vitro selection and use the natural variation in their substrate to create arrays of ZF domains displaying customized specificity. A parallel kinetic and thermodynamic characterization of ssRNA-ZFs interaction was performed by Isothermal Titration Calorimetry (ITC) and BioLayer Interferometry (BLI), respectively. Although our data showed that only little variations in the recognized sequence could be observed for the studied ZFs, they contribute to elucidate the molecular basis for the RanBP2-type ZF-ssRNA interaction. [less ▲]

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See detailHolocene paleoclimate reconstructions from belgian continental archives
Allan, Mohammed ULg; VERHEYDEN, sophie; CRUCIFIX, Michel et al

Poster (2016, June 28)

Speleothems and peatbogs presented in Belgium are interesting archives for atmospheric pollution record and climate variability. Both archives are reliable continental environmental archives of high ... [more ▼]

Speleothems and peatbogs presented in Belgium are interesting archives for atmospheric pollution record and climate variability. Both archives are reliable continental environmental archives of high interest due to their dating possibilities and their possibility to preserve multi-proxy records of environmental and climatic dynamics. Combining studies on speleothems and peatbogs from the same area will provide an age-constrained reconstruction of climatic variability at annual resolution for key intervals of the Holocene. The reconstructed precipitation and temperature curves in NW European settings, as proposed in HOPES, are essential to better constrain the Northern Hemisphere climatic record and to test climate models. Our strategy is derived from a comparative study of two continental archives speleothems and peatbogs. Time series of elemental and stable isotope geochemistry will be established for the 2 archives. For peatbog, the reconstructions of temperature (derived from stable C and O isotope), precipitation (derived from humification) and dust flux (from elementary geochemical signature) would track climate changes with subdecadal resolution. As an innovative part, Laser Ablation analyse of elemental geochemistry on impregnated peat section will allow to reach an annual resolution in the dust flux. For speleothems, records of temperature (derived from oxygen and carbon isotopic composition of calcite) and effective rainfall (derived from geochemical ratios) would reach a seasonal resolution. [less ▲]

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See detailMapping and investigating phase anomalies in GPS data onboard Low Earth Orbiters
Wautelet, Gilles ULg; Bruinsma, Sean; Loyer, Sylvain et al

Poster (2016, June 28)

To face important societal challenges like sea level variations, climate change and natural hazards management (tsunami detection, earthquakes, crustal deformations…), modern science rely more and more on ... [more ▼]

To face important societal challenges like sea level variations, climate change and natural hazards management (tsunami detection, earthquakes, crustal deformations…), modern science rely more and more on precise geodesy. Precise Orbit Determination (POD) is of major concern in the frame of altimetry or gravity recovery missions like GOCE or GRACE. Using the GPS receiver onboard, orbits at cm-level accuracy are generally achieved in both kinematic and reduced-dynamic approaches using dual frequency code and phase measurements. GPS data processing generally uses the Ionospheric-Free (IF) combination to get rid of the ionospheric delay, which is varying with the season, latitude, local time and solar activity. However, large discrepancies in the orbit determination are still observed over polar and equatorial regions, which turn into artefacts and errors in the derived scientific products (gravity field, sea surface height…). More precisely, large RMS values are strongly correlated to phase anomalies occurring on GPS receivers: cycle slips, data unavailability or enhanced measurement noise, especially on L2 signal. Phase anomalies are generally observed when the satellite orbit crosses regions where ionospheric scintillations occur, which are defined as rapid fluctuations in phase and amplitude of the GNSS signals. The occurrence of scintillations exhibits large day-to-day variations and depends mainly on geomagnetic latitude, season and local time. At low latitudes, maximum occurrence of scintillations is observed 15-20° on either side of the geomagnetic equator. Scintillations also occur at auroral and polar latitudes, where their intensity increases with increasing geomagnetic activity. This paper aims at detecting, mapping and understanding the phase anomalies experienced by LEO satellites and analyzing their correlation with geomagnetic activity, latitude, season and local time. Several LEO satellites at different altitudes are analyzed (e.g. SWARM, GRACE or JASON), which allows a multi-layer analysis of the underlying ionospheric phenomenon, including scintillation. The latter are generally measured with several indices, like the amplitude index S4 or the phase index SigmaPhi (σφ), which are usually derived from 100Hz measurements performed by dedicated scintillation monitors. In this study, we compute a similar index (called pseudo-σφ) using GPS phase data at 1Hz coming from POD GNSS antenna. A detailed study of the occurrence rate and the severity of pseudo-σφ, together with cycle slips and other spurious phase data, will be performed for different LEO satellites. [less ▲]

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See detailUnveiling new stellar companions from the PIONIER exozodi survey : follow up
Marion, Lindsay ULg; Absil, Olivier ULg; Ertel, Steve et al

Poster (2016, June 28)

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See detailConception of a near-IR spectrometer for ground-based observations of massive stars
Kintziger, Christian ULg; Desselle, Richard ULg; Loicq, Jerôme ULg et al

Poster (2016, June 27)

In our contribution, we outline the different steps in the design of a fiber-fed spectrographic instrument that intends to observe massive stars. Starting from the derivation of theoretical relationships ... [more ▼]

In our contribution, we outline the different steps in the design of a fiber-fed spectrographic instrument that intends to observe massive stars. Starting from the derivation of theoretical relationships from the scientific requirements and telescope characteristics, the entire optical design of the spectrograph is presented. Specific optical elements, such as a toroidal lens, are introduced to improve the instrument’s performances. Then, the verification of predicted optical performances is investigated through optical analyses such as resolution checking. Eventually, the star positioning system onto the central fiber core is explained. [less ▲]

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See detailThe implication of short-term memory in numerical magnitude processing: evidence from Turner syndrome
Attout, Lucie ULg; Noël, Marie-Pascale; Rousselle, Laurence ULg

Poster (2016, June 24)

Most studies on early magnitude representation focused on the visual modality with no possibility to disentangle the influence of visuo-spatial skills and short-term memory (STM) abilities on visual ... [more ▼]

Most studies on early magnitude representation focused on the visual modality with no possibility to disentangle the influence of visuo-spatial skills and short-term memory (STM) abilities on visual quantification processes. In order to specify the influence of visuo-spatial and STM processing on numerical abilities, a series of magnitudes comparison tasks differing on visuo-spatial processing requirement (no/high), on the nature of the magnitude to be processed (continuous/discrete/symbolic magnitude) and on WM demands (simultaneous/sequential presentation) were administred to twenty patients with Turner syndrome (TS), a genetic condition characterized by poor mathematical achievement, low spatial skills and reduced STM abilities. Our results showed a lower acuity than a control group matched on verbal IQ when participants with TS compared the numerical magnitudes of stimuli presented sequentially (low visuo-spatial processing and high STM load: Dot sequence and Sound sequence). No difference was observed in the numerical comparison of sets presented simultaneously or when comparing continuous and symbolic magnitude stimuli. Besides, the group difference in sequential tasks disappeared when controlling for STM abilities. These results highlight the importance of STM abilities to extract numerosity through a sequential presentation and underline the importance of considering the impact of format presentation on magnitude judgments. [less ▲]

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See detailAssaying asparagine content in a complex matrix using a spectrophotometric method
Lecart, Brieuc ULg; Jacquet, Nicolas ULg; Anseeuw, Laurent et al

Poster (2016, June 23)

In this study we show, on 15 wheat varieties, the ability to assay the asparagine content in a complex matrix such as wheat flour by a simple spectrophotometric assay. This method is easier, faster and ... [more ▼]

In this study we show, on 15 wheat varieties, the ability to assay the asparagine content in a complex matrix such as wheat flour by a simple spectrophotometric assay. This method is easier, faster and cheaper than conventional chromatography analysis and allow to discriminate quickly which materials has high or low level of this amino acid. Asparagine is an amino acid present in free form in the food biomass and has the property of reacting with the free sugars during the Maillard reactions that occur during baking at temperatures above 120°C. The Acrylamide resulting from this reaction chain has been identified as reprotoxic, genotoxic and carcinogenic in animals since 1986. The present method allowed us to identify wheat varieties with significantly lower or higher asparagine contents (α=0.05). Therefore, this method can be used to identify wheat varieties or other plants with low asparagine content to use preferentially in products designed for food. [less ▲]

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See detailRole of the Ras-GTPase activating protein Rasa3 in Angiogenesis processes
Orban, Tanguy ULg

Poster (2016, June 22)

Rasa3 is a member of the Ras GAP1 subfamily and is known to function as dual GAP (GTPase activating protein) for Ras and Rap1 smallGTPases. Homologous knockout mice expressing a catalytically-inactive ... [more ▼]

Rasa3 is a member of the Ras GAP1 subfamily and is known to function as dual GAP (GTPase activating protein) for Ras and Rap1 smallGTPases. Homologous knockout mice expressing a catalytically-inactive Rasa3 protein die during embryonic life from massive bleedings due to destabilisation of endothelial junctions. The main goal of this project is to investigate and characterize the role of Rasa3 in angiogenesis which is the process by which new blood vessels develop from pre-existing ones. Here, we show that loss of function of Rasa3 in Huvecs (Human Umbilical Vein Endothelial Cells) affects their angiogenic potential. Interestingly, we found that inactivation of Rasa3 impacts migration/adhesion-related properties of endothelial cells. Using phase contrast microscopy and TIRF technology we showed that Rasa3 inactivation doesn’t affect cell directionality and that the stronger adhesion of cells on fibronectin is due to a downregulation of adhesion turnover. We showed that these alterations can be attributed to the hyperactivation of the smallGTPase Rap1 and downregulation of FAK/SRC signalling. We suggest that in the absence of Rap1, hyperactivation of FAK/SRC following integrin engagement could explain the different phenotypes observed. Altogether these preliminary results suggested a critical function of Rasa3 in angiogenesis. [less ▲]

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See detailNatural radioactivity and elemental composition of sands in the Douala region, Littoral of Cameroon Using Portable XRF and HPGe detector
Guembou Shouop, Cébastien Joel ULg; Ndontchueng Moyo, Maurice; Chene, Grégoire ULg et al

Poster (2016, June 21)

Twenty four sand samples from seven sand quarries alone the Gulf of Guinea, Douala Littoral region of Cameroon, were analyzed using high purity germanium detector and a portable X-ray fluorescence (PXRF ... [more ▼]

Twenty four sand samples from seven sand quarries alone the Gulf of Guinea, Douala Littoral region of Cameroon, were analyzed using high purity germanium detector and a portable X-ray fluorescence (PXRF) spectrometer. A comprehensive study was conducted to determine the natural radioactivity concentrations and the geological provenience of sand samples from seven different quarries sites of the Douala, a popular city, and its surroundings. The radioactivity investigation was performed by using high resolution gamma-ray spectrometry. From the measured gamma-spectra, the average activity concentrations were determined for 226Ra, 232Th, 40K and 235U for a depth of 5–25 cm. Results of this study were compared to values from other locations around the world. X-ray fluorescence spectrometry (XRF) measurements were performed for the quantitative elemental analysis of the sands, revealing the major, minor and trace elements present in the investigated samples. Reference marine and geological sample are used to check precision and accuracy of the equipment for major and minor components. From XRF experimental results it was possible to estimate the geological provenience of the analyzed sands. These data record the radioactivity background levels in sands and could be used as reference information in Cameroon. The comparison of major (Si, Al), minor (K, Ca,Fe), and trace (Ti, Mn, Zr, Rb, Sr) element ratios was made. The results indicate that the levels of Si and Al can be very helpful in subgroup definition and provide useful clues to the raw materials used for glassmaking in Cameroon. [less ▲]

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See detailImpact of cooking and species on intestinal fermentation patterns of vegetables in a humanized in vitro model of the gastro-intestinal tract
Kalala Bolokango, Gaetan ULg; Kambashi Mutiaka, Bienvenu ULg; Njeumen Lemotio, Georges Patrick ULg et al

Poster (2016, June 21)

Obesity and associated pathologies have dramatic consequences on patients’lives as well as high societal costs. Because of the role of intestinal dysbiosis and microbiota make-up on the pathogenesis of ... [more ▼]

Obesity and associated pathologies have dramatic consequences on patients’lives as well as high societal costs. Because of the role of intestinal dysbiosis and microbiota make-up on the pathogenesis of obesity, several strategies such as eating prebiotics and dietary fibre supplements are being investigated to reshape the intestinal microbial communities of obese patients. Beyond supplement, dietary fibre is supplied through plant ingredients in the meals. In the framework of the multidisciplinary research project Food4Gut, the use of vegetables rich in specific targeted dietary fiber, namely fructans, is being scrutinized for its ability to induce positive changes in the intestinal ecophysiology. Because expected effect might differ according the content in dietary fibre and fructans, the soluble:insoluble ratio, as well as the cooking of the vegetables, the fermentation patterns of several vegetables are being investigated in an dual in vitro model combining enzymatic hydrolysis to an in vitro fermentation step using faecal inoculums from humans, to evaluate the performance of gut microbiota, modulation of metabolic functions. Six vegetables were sampled in triplicates (N=3) and steamed for 20 to 30 min.: Jerusalem artichoke, salsify, asparagus, pumpkin, fennel and swede. They were chosen because they display a variety of contents in fructans, soluble (SDF) and insoluble dietaryfibre (IDF). Steamed vegetable samplesand burgers from local fast food restaurants (negative control) were hydrolyzed in vitro why porcine pepsin and pancreatin to mimic digestion in the upper gut and indigested fiber residues were recover using a 6kDa dialysis membrane.Subsequently, in vitro fermentation is being run with independent fecal inoculums from obese and lean patients (N=4). Fermentation kinetics over 24h as well as short-chain fatty acid production and profiles will be compared according to the individual donor and the vegetable species and multivariate analysis will be used to explore the relationships between donor, vegetable species and composition and fermentation patterns. [less ▲]

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See detailAnalysis of temporal gait features extracted from accelerometer-based signals during ambulatory walking in Parkinson’s disease
Boutaayamou, Mohamed ULg; Demonceau, Marie ULg; Bruls, Olivier ULg et al

Poster (2016, June 21)

Objective: To perform a proof-of-concept study showing the utility of versatile algorithms aimed at objectively quantifying the duration of refined gait features during ambulatory walking in a patient ... [more ▼]

Objective: To perform a proof-of-concept study showing the utility of versatile algorithms aimed at objectively quantifying the duration of refined gait features during ambulatory walking in a patient with Parkinson’s disease (PD) in ON and OFF medication states as compared with an age-matched control subject. [less ▲]

Peer Reviewed
See detailUsing herbarium records to explore the ecological differentiation between closely‐related tree species in tropical Africa
Gorel, Anaïs ULg; Duminil; Doucet, Jean-Louis ULg et al

Poster (2016, June 20)

Background: Tree hypothesis are invoked to explain species distribution and evolutionary history of tree clades in tropical Africa: 1) The forest refuge hypothesis postulates that contractions of lowland ... [more ▼]

Background: Tree hypothesis are invoked to explain species distribution and evolutionary history of tree clades in tropical Africa: 1) The forest refuge hypothesis postulates that contractions of lowland forests during the climatic oscillations of the Pleistocene could have driven allopatric speciation between fragmented populations; 2) The ecological gradient hypothesis states that environmental gradients promote parapatric speciation; 3) The vanishing refuge hypothesis reconciles the two previous hypotheses and postulated a diversification process through climate-driven habitat fragmentation and exposure to new environments. Disentangling the respective influence of environmental and historical factors requires information on phylogeny, as well as information on geography and the environmental space used by species. In this study, we aimed to determine the environmental factors constraining the distribution of African tree species in order to explore ecological divergence and speciation processes. Method: We focused on three African Erythrophleum species (Fabaceae, Caesalpinioideae) that are economically and socially important, providing timber and non-timber resources. Erythrophleum ivorense, Erythrophleum suaveolens and Erythrophleum africanum also show contrasted distributions in Africa. To determine species climatic niche, we used a combination of species presence data gathered from 606 herbarium records and environmental factors (19 BIOCLIM variables). We used Species Distribution Models (SDM, MaxEnt algorithm) in combination with similarity metrics to quantify the degree of niche divergence between species. Results: We showed that the distribution of Erythrophleum species are substantially determined by climate (especially annual rainfall and temperature range) and support the ecological gradient hypothesis. Moreover, the main traits (e.g. wood density and leaf area) and growth rates previously reported among Erythrophleum species confirmed a differential adaptation to drought. Conclusion: Herbarium data provide valuable information on the distribution of species over the whole range. In tropical regions where extensive inventories data are extremely rare, herbarium records in combination with presence-only SDM offer opportunities to explore speciation processes. [less ▲]

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See detailAssessment of Myeloperoxidase activity in raw equine fresh semen
Ponthier, Jérôme ULg; Evra, Adeline; Parrilla Hernandez, Sonia ULg et al

Poster (2016, June 20)

In previous studies [1], myeloperoxidase (MPO), a pro-oxidant enzyme, has been shown to be partially inactivated in commercial equine semen extenders. The aim of this study was to determine MPO ... [more ▼]

In previous studies [1], myeloperoxidase (MPO), a pro-oxidant enzyme, has been shown to be partially inactivated in commercial equine semen extenders. The aim of this study was to determine MPO concentration and activity in fresh equine semen and in supernatant of semen diluted with a cristalloïd solution after cushionned centrifugation. Three stallions have been collected 5 times at 2 day-intervals. Semen concentration was assessed with Nucleo Counter sp100. A sample containing 100x106spz was then immediatly frozen (-80°C) before assays. A volume of semen containing 500x106spz was diluted 3 times with PBS (1v/3v). Samples were centrifuged (1000xg, 20 minutes). One milliliter of supernatant was sampled and stored at -80°C before assays. Total MPO concentration was assayed by commercial enzyme-linked immuno-sorbent assay and active MPO concentration was assayed by specific immunological extraction followed by enzymatic detection as previously described in our earlier paper [1]. As all values were not normally distributed, Kruskall-Wallis test was used to analyse differences between medians and Spearman test was used to determine correlations. Median total and active MPO concentrations in raw semen were respectively 580500ng/mL and 1.098ng/ mL. Median total and active MPO concentration in semen supernatant extended with PBS (1v/3v) were respectively 107500ng/mL and 0.236ng/mL. In raw semen, total and active MPO concentrations were highly correlated (r=0.7096; p=0.0030). However, in semen supernatant extended with PBS (1v/3v), they were not (r=0.2121; p=0.4479). Total MPO concentrations were similar to those observed in our previous papers [1]. When concentration observed in supernatant is compared to that observed in total raw semen (cells and supernatant), we observe that MPO in raw semen is higher than in supernatant, even after correction for dilution. This confirms that cellular part of semen contains MPO and releases it during cold-chock. Without any large proteins in the extender medium, MPO activity can be assessed in raw semen and in its supernatant. Active MPO concentrations are very low when compared to total MPO concentration, (nearly one million times). Concentration of active MPO in supernatant corrected for dilution was also lower than concentration observed in raw complete semen, also confirming active MPO release by cellular part of semen. Association of total and active MPO concentration is supporting this observation. This study confirms our previous assessments [1] that active and total MPO are released by non sperm-cells during cold shock. [less ▲]

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See detailVisual artificial grammar learning in children with SLI : Is variability the key ?
Desmottes, Lise ULg; Maillart, Christelle ULg; Demelenne, Pauline et al

Poster (2016, June 18)

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See detailCapturing fine-level structure using unsupervised clustering method with multiple data types
Chaichoompu, Kridsadakorn ULg; Tongsima, Sissades; Shaw, Philip James et al

Poster (2016, June 17)

Several methods exist to detect shared genetic ancestry or to identify population substructure using SNP-based or haplotype-based information (Price et al. 2006, Lawson et al. 2012). Here, we propose an ... [more ▼]

Several methods exist to detect shared genetic ancestry or to identify population substructure using SNP-based or haplotype-based information (Price et al. 2006, Lawson et al. 2012). Here, we propose an unsupervised clustering method built on the ipPCA algorithm (Intarapanich et al. 2009). Our method supports both ordinal and categorical data, and it can be applied to panels of single locus and/or multiple loci data, or gene-based integrative summaries (Fouladi et al. 2015). Our method involves an iterative process using binary and ternary splits based on multivariate Gaussian mixture modeling of PCs and Clustering EM estimation as in (Lebret et al. 2015). To evaluate its performance, we examined different simulated scenarios of 2-4 populations, 500-8,000 individuals, 5,000-20,000 independent SNPs in HWE, and FST=[0.0007,0.006] (Balding and Nichols 1995), with 100 replicates for each scenario. SNPs were treated as categorical or continuous including ancestry-corrected SNPs. Haplotype-based runs used HapMap 3 data: CHB, CHD, and JPT. In simulated scenarios of extremely subtle structure (FST=[0.0009,0.006]), a population classification accuracy of 92% or greater was obtained, which was superior to ipPCA. Also in case of the HapMap populations, promising results to detect fine structure were obtained. We are convinced that our method has a potential to detect fine-level structure and it will be important in molecular reclassification studies of patients once underlying population structure has been removed. [less ▲]

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See detailEstetrol Attenuates Neonatal Hypoxic-Ischemic Encephalopathy: Preclinical Studies
Tskitishvili, Ekaterine ULg; Nisolle, Michelle ULg; Noël, Agnès ULg et al

Poster (2016, June 17)

Brain hypoxia and ischemia due to systemic hypoxemia and reduced cerebral blood flow (CBF) are the primary causes of neonatal hypoxic-ischemic encephalopathy (HIE) accompanied by gray and white matter ... [more ▼]

Brain hypoxia and ischemia due to systemic hypoxemia and reduced cerebral blood flow (CBF) are the primary causes of neonatal hypoxic-ischemic encephalopathy (HIE) accompanied by gray and white matter injuries occurring in neonates. Perinatal HIE still remains a challenge in perinatal medicine. About 20% of affected newborns die in the postnatal period, and an additional 25% will sustain childhood disabilities. So far no medical treatment provides important neuroprotection against HIE. Studies of new neuroprotective agents in animal models of HIE may have importance for the development of new compounds and treatment strategies for this pathological condition. Estetrol (E4) is a recently described estrogen with four hydroxyl-groups that is synthesized exclusively during pregnancy by the human fetal liver. It has important antioxidative activity. To study the neuroprotective and therapeutic effects of E4 in vivo neonatal HIE model of 7-day-old newborn rat pups was used. Rat pups body temperatures were examined along with their body and brain weights. Brains were studied at the level of the hippocampus and cortex. Intact cell counting and expressions of markers for neuronal cell viability (microtubule-associated protein-2 (MAP-2)), neurogenesis (doublecortin (DCX)) and angiogenesis (vascular-endothelial growth factor (VEGF)) were evaluated by histo- and immunohistochemistry. The serum levels of brain damage markers (S100B and glial fibrillary acidic protein (GFAP)) were measured by ELISA. Our results demonstrate for the first time that E4 has a significant neuroprotective and therapeutic effects. It decreases the early gray matter loss and promotes neuro- and angiogenesis in vivo. Estetrol treatment has no effects on body weight, brain weight or body temperature. Taken together, E4 might become an important safe and physiological substance to treat neonatal HIE. [less ▲]

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See detailSequence-based association analysis identifies coding and non-coding variants in HFM1, MLH3, MSH4, MSH5, RNF212 and RNF212B with large effects on male and female recombination rate in cattle
Kadri, Naveen Kumar ULg; Harland, Chad ULg; Faux, Pierre ULg et al

Poster (2016, June 15)

We herein study genetic recombination in three dairy cattle populations from France, New-Zealand and the Netherlands. We identify 2,395,177 crossover (CO) events in sperm cells transmitted by 2,940 sires ... [more ▼]

We herein study genetic recombination in three dairy cattle populations from France, New-Zealand and the Netherlands. We identify 2,395,177 crossover (CO) events in sperm cells transmitted by 2,940 sires to 94,516 offspring, and 579,996 CO events in oocytes transmitted by 11,461 cows to 25,332 offspring. When measured in identical family structures, the average number of CO in males (23.3) was found to be larger than in females (21.4). The heritability of global recombination rate (GRR) was estimated at 0.13 in males and 0.08 in females. The genetic correlation was equal to 0.66, indicating that shared variants are influencing GRR in both genders. Haplotype-based genome-wide association studies revealed seven genome-wide significant QTL. Variants identified by next-generating sequencing in 5 Mb windows encompassing the QTL peaks were imputed in order to perform a sequence-based association analysis. For four QTLs, we identified missense mutations in genes known to be involved in meiotic recombination among the most significantly associated variants. Most of the identified mutations had significant effects in both genders with three of them accounting each for approximately 10% of the genetic variance in males (the allelic substitution effect being approximately equal to one additional CO per genome). Thus, a large fraction of the genetic variance is associated with missense mutations in genes known to be involved in meiotic recombination. Our results are very different from reports of recombination in other species. For instance, in human, recombination rate is higher in females, distinct variants affect recombination rate in males and females, and the genetic correlation is close to 0, whereas in cattle, we observed a higher recombination rate in males controlled by shared variants effective in both sexes. [less ▲]

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See detailWater Vapor Permeability of edible packaging based on native starch from improved cassava (Manihot esculenta Crantz) variety in Ivory Coast
Adjouman, Yao Désiré; Nindjin, C.; Tetchi, F.A. et al

Poster (2016, June 13)

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See detailLignin as a bio-based flame retardant additive: Pretreatments overview
Istasse, Thibaut ULg; Jacquet, Nicolas ULg; Richel, Aurore ULg

Poster (2016, June 12)

Lignin is a cross-linked phenol polymers from plant cells wall and is the third most abundant organic material after cellulose and hemicelluloses. This substance was studied as a flame retardant for ... [more ▼]

Lignin is a cross-linked phenol polymers from plant cells wall and is the third most abundant organic material after cellulose and hemicelluloses. This substance was studied as a flame retardant for various polymers and represents an interesting opportunity to create more eco-friendly and safer plastics and resins. This poster explains one potential technology to extract lignin: the organosolv treatment. [less ▲]

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See detailHOME BLOOD PRESSURE IN KIDNEY TRANSPLANT RECIPIENTS (Ktr)-VALIDITY OF DIFFERENT SCHEDULES OF SELF-MONITORING
Saint-Remy, Annie ULg; WEEKERS, Laurent ULg; BONVOISIN, Catherine ULg et al

Poster (2016, June 11)

Office blood pressure (OBP) coupled with 24-h ambulatory monitoring (24-h ABPM) or home self-monitoring (HBPM) allow a more accurate assessment of BP control in treated hypertensive patients and ... [more ▼]

Office blood pressure (OBP) coupled with 24-h ambulatory monitoring (24-h ABPM) or home self-monitoring (HBPM) allow a more accurate assessment of BP control in treated hypertensive patients and identification of different phenotypes of BP. ESH/ESC guidelines (2013) recommended 7 days of home measurements (3 days at least) but that duration is questioned. The present study examined if we can reduce, and to what extent, the 7-days schedule for home measurements in treated hypertensive kidney transplant recipients (ktr) while keeping a reliable assessment of their BP status? [less ▲]

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See detailWater familiarization testing battery adapted for young children
Vandermeulen, Mary ULg; Schietecatte, Delphine; Delvaux, Anne ULg et al

Poster (2016, June 11)

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See detailVers une approche multidimensionnelle de la procrastination.
Rebetez, Marie; Rochat, Lucien; Barsics, Catherine ULg et al

Poster (2016, June 10)

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See detailThe Computer in German Literature at the Turn of the Millennium
Dupont, Bruno ULg

Poster (2016, June 09)

This poster shows how the representation of the computer in German literature since 1990 changes the very form and content of literary works. The social importance of the computer challenges the texts on ... [more ▼]

This poster shows how the representation of the computer in German literature since 1990 changes the very form and content of literary works. The social importance of the computer challenges the texts on three levels: their topical organisation, the language used for the transcription of the new reality, and the ideological positioning on new media. [less ▲]

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See detailTowards a Digital Philology. Creation, Spread and Apprehension of Knowledge through Digital Scholarly Platforms in Humanities
Mayeur, Ingrid ULg

Poster (2016, June 09)

This contribution aims to present and discuss my thesis project. I plan to study the concrete conditions of production, diffusion and reception of knowledges on digital scholarly platforms in Humanities ... [more ▼]

This contribution aims to present and discuss my thesis project. I plan to study the concrete conditions of production, diffusion and reception of knowledges on digital scholarly platforms in Humanities. This work will especially focus on the four plateforms of the portal OpenEdition: OpenEdition Books, Calenda, Hypothèses and Revues.org. The main problematic is: what are the uses of those platforms, and in what concrete way are they influencing the modes of scientific communication? To start with, I need to highlight the frameworks that structure the digital scholarly texts, that Jeanneret named ‘architexts’ (Davallon & al. 2003, Jeanneret 2014). Such frameworks contribute to configure the digital texts (e. g. with hypertext, flows aggregation), and their uses. Three aspects will then be taken into consideration in my analysis: (I) the articulation of temporal stratums within the plateform: how do archival materials deal with actualities (scientific monitoring, work in progress as grey literature)? What means of contextualization (Treleani 2013) or editorialization (Vitali Rosati 2016) could be given when an old document is used again (e.g. in “epi-revues” that collect scientific papers) ? (II) What are the genres and formats conveyed on the plateform, proper to the Web as blog post, commentary, etc., or still used in other medias as scientific article, advert, etc. (Maingueneau 2013)? (III) Who are the users of those plateforms (researchers, groups, professionals, etc.)? How do they deal with their digital identities? How can they appropriate and diffusing knowledges, by citing, reusing and discussing? How are emerging new ways for research in Humanities, through collective negociation or evaluation, interdisciplinarity – such actions that could be promoted by the technical device of the plateform? This last point will be treated by a philological approach concerning paratexts and quotations (Genette 1982, Compagnon 1979). Other indicators (users’ itineraries, interactions between members, etc.) could also be used, and treated with network’s visualization tool. In summary, this research project aims to explore the means of a digital philology (Crane, Bamann and Jonesin Schreibman 2008; Rastier 2011), not only based on making traditional philology with digital tools (i.e. semantic enrichment of antics or medieval texts), but also on a critical approach of the digital textuality and on an active as well as reflexive contribution from the users in building knowledges. References Davallon, Jean, Marie Després-Lonnet, Yves Jeanneret, Joëlle Le Marec, and Emmanuël Souchier. 2003. Lire, écrire, récrire : Objets, signes et pratiques des médias informatisés. Études et recherche. Paris: Éditions de la Bibliothèque publique d’information. Compagnon, Antoine. 1979. La Seconde main ou le Travail de la citation. Paris: Seuil. Genette, Gérard. 1982. Palimpsestes: La littérature au second degré. Paris: Seuil. Maingueneau, Dominique. 2013. « Genres de discours et web : existe-t-il des genres web ? » In Manuel d’analyse du web en Sciences Humaines et Sociales, 74 93. Paris: Armand Colin. Mounier, Pierre, and Marin Dacos. 2010. L’édition électronique. Paris: La Découverte. Rastier, François. 2011. La mesure et le grain. Sémantique de corpus. Paris: Honoré Champion. Treleani, Matteo. 2014. Mémoires audiovisuelles: les archives en ligne ont-elles un sens? Montréal: PUM. Vitali-Rosati, Marcello. 2016. « What is editorialization? » Sens public, janvier. http://www.sens-public.org/article1059.html, consulté le 10 février 2016. Crane Gregory, David Bamman, and Alison Jonesin Schreibman, “ePhilology: When the Books Talk to Their Readers” in Susan, et Ray Siemens, éd. 2008. Companion to Digital Literary Studies. Oxford: Blackwell Publishing Professional. URL : http://www.digitalhumanities.org/companion/view?docId=blackwell/9781405148641/9781405148641.xml&chunk.id=ss1-4-1&toc.depth=1&toc.id=ss1-4-1&brand=9781405148641_brand. Consulted on 10 fev. 2016.   [less ▲]

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See detailCharacterization of FRD3, a iron and zinc homeostasis actor in Arabidopsis relatives
Scheepers, Maxime ULg; Charlier, Jean-Benoit; Spielmann, Julien ULg et al

Poster (2016, June 09)

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See detailFunctional analysis of PEBP genes in root chicory (Cichorium intybus)
Saintmard, Nicolas ULg; Tocquin, Pierre ULg; Périlleux, Claire ULg

Poster (2016, June 09)

Manipulating plant architecture is key to increase crop yield. In this perspective, basic knowledge on the molecular mechanisms regulating plant growth and development will be fundamental for the future ... [more ▼]

Manipulating plant architecture is key to increase crop yield. In this perspective, basic knowledge on the molecular mechanisms regulating plant growth and development will be fundamental for the future of agriculture. Recent progress indicates that a family of plant genes, homologous to POSPHADITYLETHANOLAMINE-BINDING PROTEINS (PEBP) in other eukaryotes, plays critical roles in controlling shoot development traits such as branching, flowering, bud dormancy or tuberization. Very little is known however on the functions of these genes in root development. The current research will attempt to answer this question in the case of Cichorium intybus, a biannual plant cultivated for the extraction of inulin (a polymer of fructose) from its root. Functional analyses will include expression kinetics, complementation tests in Arabidopsis mutants and creation of PEBP- overexpressing or silencing chicory plants. The preliminary steps of the project are the identification of PEBP genes in chicory by in silico analyses, the determination of the time of the storage root initiation and the establishment of a regeneration protocol for the genetic transformation. [less ▲]

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See detailMALDI-imaging guided microproteomics workflow for biomarker discovery of intra-tumor heterogeneity
Alberts, Deborah ULg; Longuespée, Rémi ULg; Smargiasso, Nicolas ULg et al

Poster (2016, June 09)

Introduction A single tumoral tissue can bear phenotypically different cell populations. This phenomenon called intra-tumor heterogeneity can lead to differential behaviors regarding metastasis seeding ... [more ▼]

Introduction A single tumoral tissue can bear phenotypically different cell populations. This phenomenon called intra-tumor heterogeneity can lead to differential behaviors regarding metastasis seeding and therapy resistance [Zardavas et al., Nature Rev. Clin. Onc. 2015]. MALDI imaging has proven its efficiency for revealing hidden molecular features offering an insight into distinct cellular regions based on their molecular content. Further, proteomics applied to these regions could allow depicting the molecular context associated to particular cells groups and enable the collection of qualitative, quantitative and spatial information for each protein. Methods Breast cancer Formalin Fixed and Paraffin Embedded tissues, from patients whose outcome had been recorded over a period of 10 years, were provided by the department of Pathology of University of Liège. After Citric Acid Antigen Retrieval and trypsin digestion, images were obtained by MALDI-TOF/TOF-MS (Bruker, Germany). From the obtained datasets, segmentation and analytical data analysis were applied using SCiLS (Bruker, Germany) and the cloud software Multimaging (ImaBiotech, France). Small tissue areas were obtained by laser microdissection (LEICA LMD 700, Germany), upon which a combination of chemical processes was applied to ensure optimal protein antigen retrieval, extraction and digestion. Finally, the tissue pieces obtained were analyzed by LC-MS/MS using UPLC Waters Nanoacquity and Thermo Q-Exactive instruments. Preliminary data Based on mathematical calculations for the MALDI imaging datasets of the breast cancer FFPE tissues, Regions Of Interest (ROIs) were detected in a single tumor, revealing intra-tumoral heterogeneity, which can be correlated to the level of aggressiveness of the affliction and to the final prognosis of the patient. We aimed to compare the proteomic profiles of each of the small ROIs. Until today, proteomics applied to tissues composed by a restricted number of cells is quite tedious due to possible tissue losses during their handling. Recently, Longuespée [Longuespée et al., Methods 2015] published a method in order to retrieve the identification of 1400 proteins from microdissected tissue pieces containing only 2700 cells. This whole procedure allowed us to identify a panel of protein that characterizes tissue heterogeneity within a single tumor. This proves the applicability of the combination of MALDI imaging for the discovery of intra-tumoral heterogeneity without a priori, on a mathematical basis, and classical proteomics applied on laser-microdissected tissue samples of very restricted areas. This method will now be applied to several MALDI datasets in order to retrieve commune ROIs and to associate their presence with the information of each patient, such as their prognosis. Those ROIs will then be microdissected and subjected to microproteomic methods that will allow us to retrieve the extensive molecular context associated to bad patient prognosis and/or therapy resistance. The possibility to identify protein/peptide markers will have the power to predict the outcome of the breast cancer patient at the beginning of their treatment, and thus, improve the clinical care for the benefit of the patients. Novel aspect The workflow combines the unique advantages of MALDI imaging for de novo molecular features characterization and LMD-based microproteomics. [less ▲]

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See detailAg/SiO2 and Cu/SiO2 cogelled xerogel catalysts for benzene combustion and 2-butanol deshydrogenation
Mahy, Julien ULg; Claude, Vincent ULg; Tasseroul, Ludivine ULg et al

Poster (2016, June 08)

Tars are recognized as major impurities when biomass is gazified into Syngas (mixture CO + H2) or when the methane reforming was produced from sustainaible reagents [1]. Therefore, fundamental knowledge ... [more ▼]

Tars are recognized as major impurities when biomass is gazified into Syngas (mixture CO + H2) or when the methane reforming was produced from sustainaible reagents [1]. Therefore, fundamental knowledge of catalytic oxidation and deshydrogenation mechanisms can be valuable to develop effective methods to control syngas or methane pollution. A very important concern about cogelled catalysts is the accessibility of the active centers. Because the silver and copper is located inside silica particles, there is a risk that it may not be accessible. In the case of benzene oxidation, it was observed that the specific activity (mol s-1 g-1Ag) of Ag/SiO2 and Cu/SiO2 catalysts increases when the silver or copper loading decreases (Fig. 1). In fact, visual observations by TEM showed that in samples Ag0.25, Ag0.45, Ag1.05 and Cu1.00, there are not silver or copper particles located on silica particles external surface and then the metal dispersion values are greater in these samples. So, it is the proof that Ag and Cu particles located inside the silica particles are accessible for benzene in this catalytic system. In the case of 2-butanol dehydrogenation, the specific activity of Cu/SiO2 catalysts increases when the copper loading increases or when the metal dispersion values decreases (Fig. 2). However, in Cu1.00 sample, copper particles inside silica particles only are observed by TEM. It seems that these metallic particles are accessible for 2-butanol in this catalytic system. [less ▲]

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See detail50Hz EMF and public health policy: The involvement of the Belgian BioElectroMagnetics Group
Ledent, Maryse ULg; Maes, Annemarie; De Ridder, Maurits et al

Poster (2016, June 07)

The BBEMG website (www.bbemg.be) aims to present the results of the research teams of the Belgian BioElectroMagnetics Group, to inform about electric and magnetic fields and their potential health effects ... [more ▼]

The BBEMG website (www.bbemg.be) aims to present the results of the research teams of the Belgian BioElectroMagnetics Group, to inform about electric and magnetic fields and their potential health effects, and to become a centre of documentation and education able to provide understandable and correct information regarding 50 Hz electric and magnetic fields to the general public, physicians, scientists, public officials... This paper is focusing on the involvement of the BBEMG through its website in the Belgian public policy, its identified goals and how it is implemented and evaluated. Challenges will also be analysed. [less ▲]

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