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See detailTargeted and random mutagenesis of orphan GPCRs of the SREB family
Laschet, Céline ULg; Dupuis, Nadine ULg; Derj, Anouar ULg et al

Poster (2016, January 25)

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See detailUnravelling the roles of lysine acetylation by Elp3 during inner ear development
Mateo Sanchez, Susana ULg; Delacroix, Laurence ULg; Freeman, Stephen ULg et al

Poster (2016, January 25)

We planned to investigate the role of Elp3 acetyl-transferase, a member of the Elongator complex, in inner ear formation. We first analysed the spatio-temporal pattern of Elp3 mRNA expression and showed ... [more ▼]

We planned to investigate the role of Elp3 acetyl-transferase, a member of the Elongator complex, in inner ear formation. We first analysed the spatio-temporal pattern of Elp3 mRNA expression and showed that it was expressed in the entire early otocyst at E11.5 and persisted later in the sensory epithelium of the cochlea, in the spiral ganglion and in the vestibule. To unravel functions of Elp3, we used conditional knock-out mice in which Elp3 gene is deleted from early otocyst (Elp3cKO). We submitted these mice to a battery of vestibular testing and found significant abnormalities. Besides, the auditory brain stem response of Elp3cKO indicated that these mice are severely deaf. We were also able to demonstrate an increased level of apoptosis in the Elp3cKO spiral ganglion leading to a reduced number of neurons and fibers innervating the sensory cells as well as a reduced number of their synaptic ribbons. Moreover, the remaining spiral ganglion neurons extend processes showing clearly defects regarding sensory cell innervation. In conclusion, our results clearly show a role for Elp3 both in hearing and balance. We plan to go deeper in the mechanisms involved through the identification of the proteins that are targeted for acetylation by Elp3. [less ▲]

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See detailDe novo sequencing using MELD proteolysis coupled to a "sequence assembly" algorithm
Mazzucchelli, Gabriel ULg; Zimmerman, Tyler A; Smargiasso, Nicolas ULg et al

Poster (2016, January 22)

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See detailÉtude des expériences corporelles anormales dans la schizophrénie
Englebert, Jérôme ULg; Lancellotti, Elisa

Poster (2016, January 20)

L’objectif de notre recherche est l’étude des expériences corporelles anormales (Abnormal Bodily Experiences [ABE]) chez les personnes diagnostiquées schizophrènes. En plus de nous inspirer des résultats ... [more ▼]

L’objectif de notre recherche est l’étude des expériences corporelles anormales (Abnormal Bodily Experiences [ABE]) chez les personnes diagnostiquées schizophrènes. En plus de nous inspirer des résultats de l’étude de Stanghellini et al. (2012), nous nous référerons également au troisième domaine de l’échelle d’Evaluation des Anomalies de l’Expérience de soi [EASE] qui explore spécifiquement les « Expériences corporelles ». Nous suivons une méthode d’analyse dites « empirico-phénoménologique ». Cette dernière est « empirique » car elle se base sur l’analyse des descriptions des expériences et comportements des patients, et « phénoménologique » car l’ensemble des phénomènes décrits est envisagé comme des façons d’entrer en relation avec le monde et autrui. Le questionnaire semi-structuré que nous avons créé est composé de vingt questions comprenant six catégories (seize sous-catégories) : dysmorphies, dépersonnalisation somatique et étrangetés corporelles, objectivations morbides, expériences cénesthésiques, perturbations motrices, expériences mimétiques. Notre échantillon est composé de cinquante sujets schizophrènes hospitalisés. Les entretiens semi-structurés se déroulent en deux parties. Durant la première séance, nous avons administré le questionnaire dont l’ordre varie en fonction des réponses et de l’attitude du patient. Lors de la seconde rencontre, nous faisions un feedback au patient. Cela nous a permis de vérifier la concordance des réponses à travers le temps. À travers l’analyse des résultats, nous observons que les ABE sont des symptômes très présents chez les personnes souffrant de schizophrénie. Nous observons également que toutes les catégories et sous-catégories sont présentent dans notre échantillon. Ces résultats devraient permettre d’affiner et préciser le diagnostic de schizophrénie et d’ouvrir des perspectives concernant la dimension psychothérapeutique. [less ▲]

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See detailRéflexion psychopathologique sur le diagnostic d’héboïdophrénie
Englebert, Jérôme ULg; De Page, Louis

Poster (2016, January 20)

Le concept d’héboïdophrénie a été proposé par Kalhbaum en 1890. S’il parcourt le XXème siècle à travers les grands systèmes nosographiques, il n’obtiendra jamais qu’une place secondaire voire marginale ... [more ▼]

Le concept d’héboïdophrénie a été proposé par Kalhbaum en 1890. S’il parcourt le XXème siècle à travers les grands systèmes nosographiques, il n’obtiendra jamais qu’une place secondaire voire marginale parmi les entités psychopathologiques de référence. Il est d’ailleurs absent des différents DSM (y compris la récente 5ème version). L’on ajoutera que, si elle est née en Allemagne, l’héboïdophrénie a surtout été discutée dans le giron de la psychopathologie française. Cette psychopathologie se caractérise par une symptomatologie psychotique de type schizophrénique et des troubles du comportement de type antisocial. Cette symptomatologie « bicéphale » – d’une part psychotique et d’autre part psychopathique –, a classiquement été associée à la pathogénie de certaines schizophrénies, notamment en incarnant une forme d’entrée typique et précoce dans le trouble. Une hypothèse psychopathologique et compréhensive souvent retenue est que le comportement antisocial pourrait répondre à la gestion difficile de l’angoisse psychotique naissante. L’on peut alors suggérer une interaction et une influence mutuelle entre les pôles antisocial et schizophrénique. La prise en considération de ce diagnostic peut se révéler utile en psychopathologie légale : ces patients interrogent de façon complexe la notion de « responsabilité » et ont souvent, au préalable, échappé aux soins et aux circuits psychiatriques classiques. Nous présenterons plusieurs données cliniques issues de notre pratique, mais également des données empiriques préliminaires. Notre objectif est de montrer qu’une prise en considération de ce diagnostic peut avoir grand intérêt dans le contexte médico-légal dans lequel apparaissent ces patients. C’est, selon nous, grâce à une réflexion psychopathologique approfondie – incluant notamment une analyse des thématiques délirantes, une étude des contextes de formation de ces idées, et sur une prise en considération de l’évolution existentielle du trouble schizophrénique – que les complexes questions de dangerosité et de récidive (le risk), et de thérapeutique, de prise en charge et de réinsertion (le care) pourront être mieux posées. [less ▲]

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See detailInsight et expériences anormales du soi dans la schizophrénie : une étude phénoménologique
Englebert, Jérôme ULg; Baillion, Marie

Poster (2016, January 20)

Le terme d'insight désigne la conscience et la compréhension que le malade a de son trouble mental (Raffard, 2007). La prévalence du manque d'insight dans la schizophrénie est élevée puisque 50 à 80% des ... [more ▼]

Le terme d'insight désigne la conscience et la compréhension que le malade a de son trouble mental (Raffard, 2007). La prévalence du manque d'insight dans la schizophrénie est élevée puisque 50 à 80% des patients n'aurait pas conscience de leur maladie (Amador et Gorman, 1998). L'objectif de notre étude est d'investiguer la conscience qu’une personne atteinte de schizophrénie a de ses troubles en utilisant une méthodologie d’inspiration phénoménologique. Pour atteindre notre objectif, nous avons choisi un outil issu des travaux de la psychopathologie phénoménologique. L’échelle EASE [Evaluation des Anomalies de l'Expérience de Soi] (Parnas et al., 2012) permet d'appréhender la conscience des troubles de façon qualitative et selon une perspective en première personne. Nous avons également utilisé le Self-Appraisal of Illness Questionnaire (SAIQ, Marks et al. 2000), permettant l'évaluation de l'insight de manière quantitative. Notre population, composée de sujets schizophrènes, est divisée en deux groupes : ceux ayant un bon insight et ceux ayant un faible (révélés par le SAIQ). Nous avons évalué la conscience des troubles à l'aide de l’EASE chez 14 hommes schizophrènes de 51 ans d’âge moyen. Notre hypothèse était que, plus le sujet peut parler des expériences qu'il vit – donnée qualitative que nous évaluons avec l'échelle EASE qui facilite l'énonciation de ses troubles – plus le sujet a conscience de sa maladie. Les deux tiers de notre échantillon confirment notre hypothèse. Notre étude met en exergue que l’insight est un phénomène difficile à appréhender qui mérite d’être étudié dans une perspective en première personne. Parnas et Henriksen (2014) estiment que l’échec de programmes thérapeutiques et de psychoéducations ainsi que la faible observance de la médication est souvent le résultat d'une compréhension inadéquate de la nature du concept d’insight dans la schizophrénie. [less ▲]

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See detailCorps-pour-autrui et anorexie mentale : une étude étho-phénoménologique
Englebert, Jérôme ULg; Minguet, Eugénie

Poster (2016, January 20)

D’un point de vue phénoménologique, les patientes souffrant d’anorexie mentale semblent confrontées à des perturbations fondamentales au niveau de l’incarnation (embodiment) et de l’intersubjectivité. Par ... [more ▼]

D’un point de vue phénoménologique, les patientes souffrant d’anorexie mentale semblent confrontées à des perturbations fondamentales au niveau de l’incarnation (embodiment) et de l’intersubjectivité. Par conséquent, cette étude évalue les expériences corporelles subjectives de participantes anorexiques à la lumière du concept du corps-pour-autrui de Sartre ainsi que des hypothèses éthologiques de Demaret concernant l’altruisme. Deux hypothèses principales, intrinsèquement liées, structurent cette recherche. La première envisage des difficultés concernant l’intersubjectivité, les patientes anorexiques se définissant davantage à travers le regard des autres et tendant à moins ressentir leur corps de manière sensorielle. La deuxième hypothèse suggère que les anorexiques font preuve de plus d’altruisme, qu’il soit alimentaire ou général. Cet altruisme constituerait un élément central du syndrome anorexique. Pour tester les hypothèses, l’EDI-II (Eating Disorder Inventory), la traduction française du questionnaire IDEA (IDentity and EAting disorder) mesurant le concept du corps-pour-autrui et des questions complémentaires abordant le concept d’altruisme ont été administrées à 67 patientes anorexiques francophones et 246 participantes contrôles ne présentant pas de trouble du comportement alimentaire (TCA). Les résultats des analyses statistiques confirment nettement les deux hypothèses : les patientes anorexiques obtiennent des scores aux questionnaires significativement supérieurs à ceux des participantes contrôles. De façon globale, la psychopathologie anorexique présenterait bien comme signe cardinal des difficultés au niveau de l’incarnation et de l’intersubjectivité. De plus, malgré le fait que les questions relatives à l’altruisme doivent être davantage confirmées et investiguées, les patientes anorexiques se révéleraient nettement plus altruistes que les participantes sans TCA. Nous présenterons également deux brèves analyses de cas qui permettront de mieux comprendre les particularités de l’être-au-monde anorexique. [less ▲]

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See detailAnomalies de l’expérience de soi dans la schizophrénie : Comparaison avec les représentations des proches
Englebert, Jérôme ULg; Lo Presti, Fanny

Poster (2016, January 20)

Notre objectif est de comparer les expériences (inter-)subjectives de personnes souffrant de schizophrénie avec la perception que leurs proches en ont. L'instrument de mesure utilisé est l'échelle EASE ... [more ▼]

Notre objectif est de comparer les expériences (inter-)subjectives de personnes souffrant de schizophrénie avec la perception que leurs proches en ont. L'instrument de mesure utilisé est l'échelle EASE (Évaluation des Anomalies de l’Expérience de Soi) qui permet, dans une orientation phénoménologique, une exploration semi-structurée en première personne des troubles de la conscience de soi. L'échantillon est composé de cinq personnes atteintes de schizophrénie et de cinq proches. Il a été demandé au patient de choisir comme « proche » la personne la plus significative pour lui. L’hypothèse centrale sur laquelle repose notre étude est qu’il existe une différence qualitative entre le discours du patient (perspective en première personne) et les représentations du proche (perspective en troisième personne). Les entrevues semi-structurées se sont déroulées individuellement, d’abord avec le patient, ensuite avec le proche. Les résultats de cette étude qualitative sont nombreux et suggèrent de nombreuses pistes d’analyse. L’une d’elle suggère notamment que les impressions des proches concernant le vécu (inter-)subjectif des patients dépendrait particulièrement de leur connaissance de la maladie de manière générale, de la qualité des échanges avec le patient mais aussi de leur regard/avis concernant la maladie. Nous observons que la communication est nettement plus présente chez les deux binômes de notre échantillon ayant le moins de différence entre les deux discours. De plus, ces deux binômes étaient également composés des deux patients les plus jeunes. Nous pourrions, dès lors, suggérer que les proches seraient plus attentifs au comportement du patient lors des premières phases de la maladie et que leurs démarches pour comprendre cette dernière soient également plus actives. [less ▲]

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See detailComparaison des performances des modèles d'analyse discriminante PLS et SVM
Eylenbosch, Damien ULg; Fernández Pierna, Juan Antonio; Baeten, Vincent et al

Poster (2016, January 19)

Les performances des modèles d’analyses discriminantes PLS (Partial Least Squares) et SVM (Support Vector Machines) ont été comparées dans une étude qui avait pour objectif de discriminer des spectres ... [more ▼]

Les performances des modèles d’analyses discriminantes PLS (Partial Least Squares) et SVM (Support Vector Machines) ont été comparées dans une étude qui avait pour objectif de discriminer des spectres proches infrarouges sur base d'images hyperspectrales de racines et de pailles de froment en vue de les quantifier. [less ▲]

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See detailChemometrics and vibrational spectroscopy for the detection of melamine levels in milk
Fernandez Pierna, Juan; Vincke, Damien; Baeten, Vincent et al

Poster (2016, January 19)

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See detailSingle molecule force spectroscopy on synthetic foldamers
Devaux, Floriane ULg; Li, Xuesong; Ivan, Huc et al

Poster (2016, January)

Inspired by the many folded conformations of the molecular machineries responsible for chemical reactions and mechanical tasks in nature, such as enzyme catalysis and duplication in nucleic acids ... [more ▼]

Inspired by the many folded conformations of the molecular machineries responsible for chemical reactions and mechanical tasks in nature, such as enzyme catalysis and duplication in nucleic acids, chemists have been developing the syntheses of artificial folded molecular architectures, namely foldamers (Guichard and Huc, 2011). The investigation of these molecules using AFM-based Single Molecule Force Spectrosocopy (SMFS) allows the elucidation of both mechanochemical properties and conformational dynamics on the unimolecular scale in solution. The stepwise synthesis of aromatic oligoamide-based foldamers was designed (Jiang et al., 2003; Huc, 2004) to produce well-defined helically-folded molecular architectures. A poly(ethylene oxide) PEO tether was coupled to one end of the foldamer. This tether design enables the coupling with the AFM tip and increases the number of potentially accessible physicochemical parameters through SMFS experiments. SMFS pulling experiments on this system yielded specific and reproducible force-extension patterns characteristic of single foldamers. Those patterns were further analyzed to determine unfolding forces and dynamics as well as to propose mechanistics hypotheses of the unfolding process. Several helical foldamers presenting variable lengths were considered. Experiments in multiple solvents pointed out a variation in the foldamer stability, leading to different average forces values. This last study enabled us to modulate the intramolecular interactions responsible for the folding and to evaluate the mechanochemical properties of the helix. The force values measured for those foldamers are higher than those previously measured in natural biopolymers (Clausen-Schaumann et al., 2000; Janshoff et al., 2000), showing a high stability under a load and a propensity for the development of emergent properties. In addition, the increased stability of these aromatic oligoamide foldamers was confirmed by the observation of almost instantaneous reversibility of the unfolding under load. [less ▲]

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See detailApplication of a standardisation procedure on an international network of MIR instruments for milk analysis
Grelet, Clément ULg; Fernandez Pierna, Juan A.; Dardenne, Pierre et al

Poster (2016, January)

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See detail"Quand voyager mentalement dans le temps est difficile) - Une étude comparative des souvenirs et projections définissant le soi chez des patients dépressifs et des sujets contrôles sains
Wagener, Aurélie ULg; Thirion, Julie; PITCHOT, William ULg et al

Poster (2016, January)

INTRODUCTION. Les patients dépressifs présentent des difficultés à effectuer le voyage mental dans le temps, une des fonctions principales de la mémoire autobiographique, c’est-à-dire à se projeter ... [more ▼]

INTRODUCTION. Les patients dépressifs présentent des difficultés à effectuer le voyage mental dans le temps, une des fonctions principales de la mémoire autobiographique, c’est-à-dire à se projeter mentalement dans le passé et le futur. Cette étude s’intéresse à des événements passés et futurs potentiels particuliers qui sont les souvenirs et les projections futures définissant le soi (SDS et PFDS, respectivement). Les SDS et les PFDS sont des événements autobiographiques particuliers hautement pertinents pour l’identité de l’individu et qui l’aident à se définir. Plus précisément, les SDS sont considérés comme une cristallisation des liens entre mémoire et identité. Le premier objectif de cette étude est d’évaluer les caractéristiques de ces SDS et des PFDS (spécificité, intégration, valence émotionnelle, modification de la valence émotionnelle pour les SDS) chez des patients dépressifs, en comparaison à des sujets contrôles sains. Le second objectif est d’évaluer les liens entre les caractéristiques des SDS et des PFDS avec la clarté du concept de soi. HYPOTHÈSES. Les patients dépressifs rapporteront des SDS et des PFDS moins spécifiques, moins intégrés et plus négatifs que les sujets contrôles sains. Ceci sera en lien avec une faible clarté du concept de soi. MÉTHODE. 19 patients dépressifs et 17 sujets contrôles sains appariés (sexe, âge, niveau d’éducation) ont évoqué des SDS et des PFDS en fonction de domaines de vie (ex. : relations familiales, hobbies, emploi/carrière). RÉSULTATS. La récolte des données est toujours en cours. Les résultats préliminaires mettent en évidence que les patients dépressifs évoquent des SDS et des PFDS moins intégrés que les sujets contrôles. Les patients dépressifs rapportent également davantage de séquence de contamination dans le rappel de SDS (la valence de l’événement lorsqu’il s’est déroulé était positive et devient négative lors de l’évocation du souvenir). DISCUSSION. Les résultats obtenus confirment partiellement nos hypothèses. Ces résultats semblent cohérents avec certains biais préalablement observés dans l’évocation de souvenirs autobiographiques tels que le biais de congruence à l’humeur. Les implications cliniques de ces résultats seront discutées. [less ▲]

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See detailImplications of spatial and temporal variation in point technology in KwaZulu-Natal during the MSA
Bader, Gregor; Porraz, Guillaume; Rots, Veerle ULg et al

Poster (2016)

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See detailUnexpected sensitivity of the annual net ecosystem exchange to the high frequency loss corrections in a grazed grassland site in Belgium
Mamadou, Ossénatou ULg; Gourlez de la Motte, Louis ULg; De Ligne, Anne ULg et al

Poster (2016)

The eddy covariance technique is widely used to measure CO2 and other gas fluxes. However, eddy covariance fluxes are affected by systematic errors that must be corrected. Among them, high frequency loss ... [more ▼]

The eddy covariance technique is widely used to measure CO2 and other gas fluxes. However, eddy covariance fluxes are affected by systematic errors that must be corrected. Among them, high frequency loss corrections are particularly important in this regard, especially when using a closed-path infrared gas analyzer. In this study, we compared three approaches to do these corrections for CO2 fluxes and evaluated their impact on the carbon balance an intensively grazed grassland site in Belgium . In the first approach, the computation of correction factors was based on the measured sensible heat cospectra (‘local’ cospectra), whereas the other two were based on theoretical models (Kaimal et al., 1972). The correction approaches were validated by comparing the nighttime eddy covariance CO2 fluxes corrected with each approach and in situ soil respiration measurements. We found that the local cospectra differed from the Kaimal theoretical shape, although the site could not be considered ‘difficult’ (i.e., fairly flat, homogeneous, low vegetation, sufficient measurement height), appearing less peaked in the inertial subrange. This difference greatly affected the correction factor, especially for night fluxes. Night fluxes measured by eddy covariance were found to be in good accord with in situ soil respiration measurements when corrected with local cospectra and to be overestimated when corrected with Kaimal cospectra. As the difference between correction factors was larger in stable than unstable conditions, this acts as a selective systematic error and has an important impact on annual fluxes. On the basis of a 4-year average, at DTO the errors reach 71-150 g C m-2 y-1 for net ecosystem exchange (NEE), 280-562 g C m-2 y-1 for total ecosystem respiration (TER) and 209-412 g C m-2 y-1 for gross primary productivity (GPP), depending on the approach used. We finally encourage site PIs to check the cospectrum shape at their sites and, if necessary, compute frequency correction factors on the basis of local cospectra rather than on Kaimal cospectra. [less ▲]

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See detailCarbon balance of an intensively grazed grassland in southern Belgium
Gourlez de la Motte, Louis ULg; Jérôme, Elisabeth; Mamadou, Ossénatou ULg et al

Poster (2016)

Grasslands are an important component of the global carbon balance but their carbon storage potential is still highly uncertain. Especially, the impact of weather variability and management practices on ... [more ▼]

Grasslands are an important component of the global carbon balance but their carbon storage potential is still highly uncertain. Especially, the impact of weather variability and management practices on grassland carbon budgets need to be assessed. This study investigates the carbon balance of an intensively managed permanent grassland in southern Belgium and its uncertainties by combining 5-years of eddy covariance measurements and other organic carbon exchanges estimates. The specificities of this study lie in: (i) the age of the pasture, which has probably been established since more than one century; (ii) the intensive character of the management with a mean grazing pressure larger than 2 livestock unit ha-1 and stocking cycle including stocking and rest periods, (iii) the livestock production system, typical of Wallonia, farming intensively Belgian Blue breed of cattle in order to produce meat. The results showed that, despite the high stocking rate and the old age of the pasture and the high stocking rate, the site acted as a relatively stable carbon sink from year to year with a 5-year average Net Biome Productivity of ‒173 [‒128 ‒203] g C m-2 yr-1. The carbon sink behavior of the pasture was directly increased by management practices through food complementation and organic fertilization and indirectly by mineral fertilization. The relatively low carbon budget inter-annual variability could be explained both by: (i) grazing management of the farmer that regulated Growth Primary Productivity by adapting the stocking rate to the Leaf Area Index which itself depends on weather conditions, (ii) carbon imports through food complements only when grass regrowth was not sufficient to feed the cattle. An exception occurred when low temperatures at the beginning of the year and a prolonged snow period provoked a delay in grass growth and therefore Growth Primary Productivity that could not be completely offset during the rest of the year. The results suggest that management practices that tend to optimize forage availability for meat production could contribute to maintaining a carbon sink. [less ▲]

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See detailThe Fractal Nature of Mars Topography Analyzed via the Wavelet Leaders Method
Kleyntssens, Thomas ULg; Deliège, Adrien ULg; Nicolay, Samuel ULg

Poster (2016)

This work studies the scaling properties of Mars topography based on Mars Orbiter Laser Altimeter (MOLA) data through the wavelet leaders method (WLM). This approach shows a scale break at 15 km. At small ... [more ▼]

This work studies the scaling properties of Mars topography based on Mars Orbiter Laser Altimeter (MOLA) data through the wavelet leaders method (WLM). This approach shows a scale break at 15 km. At small scales, these topographic profiles display a monofractal behavior while a multifractal nature is observed at large scales. The scaling exponents are greater at small scales. They also seem to be influenced by latitude and may indicate a slight anisotropy in topography. [less ▲]

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See detailStudy of cell growth on/in modified polymer matrices as scaffolds for tissue engineering
Markvicheva, E.; Drozdova, M.; Demina, T. et al

Poster (2016)

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See detailResting-state test-retest reliability over different preprocessing steps
Varikuti, Deepthi; Hoffstaedter, Felix; Genon, Sarah ULg et al

Poster (2016)

Introduction: Resting-state (RS) functional connectivity (FC) analysis has become a widely used method for the investigation of human brain connectivity and pathology. While most of the current ... [more ▼]

Introduction: Resting-state (RS) functional connectivity (FC) analysis has become a widely used method for the investigation of human brain connectivity and pathology. While most of the current applications are based on data-driven analyses, the use of functionally specific, a priori defined networks provided by neuroimaging meta-analyses represent an important alternative to these, as they allow the standardized assessment of connectivity patterns. Neuronal activity as measured by functional MRI is influenced by various nuisance signals including system noise, thermal noise, and noise induced by physiological processes of the participant. The presence of these confounds in turn have an impact on the estimation of functional connectivity. Several methods exist to deal with this predicament, but little consensus has yet been reached on the most appropriate approach. Given the crucial importance of reliability for the development of clinical applications, we investigated the test-retest reliability of FC analyses in meta-analytically defined networks after removing confounding noise regressors. Methods: RS-fMRI data of 42 healthy subjects with an average age of 42 ± 20 years were obtained in two sessions with an average time interval of 175 ± 75 days. A seed-based FC analysis was conducted after spatial preprocessing, approach specific confound-regression, and band-pass filtering [0.01-0.08 Hz]. We focused on the effects of various commonly used confound removals in the resting state studies such as PCA de-noising, global mean signal regression, and removal of tissue-class specific mean signals (in particular, white matter (WM) + cerebrospinal fluid (CSF) and WM + CSF + grey matter (GM)) [2,3,4,5,7]. Additionally, we examined GM specific time-series extraction from seed regions. In order to compute the seed based FC, a priori defined networks were analyzed (extended socio-affective default mode [1] and working-memory [6]). Both networks show robust within network resting state connectivity as well as anti-correlation between each other. The reliability of FC was measured using two different measures Spearman correlations and the absolute differences of functional connectivity scores. The different approaches defined by the combination of different masking / confound removal approaches were compared using a non-parametric Friedman ANOVA. Results: The summary ranking across both indices of reliability (Spearman correlations and absolute differences) reflects the major patterns noted in the individual analyses (Fig.1). GM masking, in particular using the group-mean segmentation, improves reliability. PCA denoising in turn reduces it. Within-network connections are most reliably estimated when not using any global or tissue-class specific signal regression, with removing the global WM and CSF signals representing the next-best approach. In contrast, between-network connections are most reliably measured by linear and second order removal of global signals of all three-tissue classes. Conclusion: Our results show that GM masking of the seed regions based on the group-average GM probabilities is advisable when investigating meta-analytically defined networks. In turn, PCA de-noising reduces the reliability of connectivity estimates. Finally, with respect to global signal regression, we observe that refraining from this approach enhances reliability, but comes at the expense of potentially poorer biological validity, indicated by missing anti-correlations between what has been previously described as antagonistic networks. Here, removal of global WM and CSF signals seems to provide a good compromise, as this approach yielded reliable and meaningful estimates of within and between-network connections (Fig.2). We noted that reliability is proportional to the retained variance, presumably including structured noise. Consequently, we would argue that compromises are needed between maximizing reliability and removing variance that may be attributable to non-neuronal sources. [less ▲]

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See detailAnalyzing but Not Buying: The Mere Exposure Effect on Children’s Behavior in an Ecological Context
Geurten, Marie ULg; Geurten, Claire ULg; Willems, Sylvie ULg

Poster (2016)

The mere exposure effect is usually considered a robust phenomenon whereby people’s attitudes can easily be influenced. However, recent studies suggest that some conditions must be met for this effect to ... [more ▼]

The mere exposure effect is usually considered a robust phenomenon whereby people’s attitudes can easily be influenced. However, recent studies suggest that some conditions must be met for this effect to emerge. In this experiment, the influence of the features of a specific material on the mere exposure effect was examined in an ecological context. Children were told that they would play a game during which they would have to buy several items in different shops. In these shops, half of the participants were incidentally exposed to two target stimuli. During a subsequent judgment phase, the target stimuli were presented to each child, either with perceptually similar items or with perceptually dissimilar items. Prior encounter with an item only influenced children’s preference choices when the test items were dissimilar. These findings are discussed in terms of the processing styles that are necessary for the mere exposure effect to appear. [less ▲]

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See detailMultimodal evidence of a rostro-caudal and ventro-dorsal organization in the dorsal premotor cortex
Genon, Sarah ULg; Li, Hai; Fan, Lingzhong et al

Poster (2016)

Introduction Different methods for in-vivo characterization have resulted in different maps of the human dorsal premotor cortex (PMd): Task-based functional studies suggested a rostro-caudal gradient ... [more ▼]

Introduction Different methods for in-vivo characterization have resulted in different maps of the human dorsal premotor cortex (PMd): Task-based functional studies suggested a rostro-caudal gradient corresponding to a cognitive-motor gradient1,2 and mapping based on resting-state functional connectivity (RSFC) likewise suggested a subdivision along the rostro-caudal axis3. In contrast, mapping based on structural connectivity as assessed by probabilistic diffusion tractography (PDT) provided evidence that the dorsal part of the precentral gyrus (PG) is organized along a ventro-dorsal axis4. However, there is currently no multimodal mapping of a broadly defined PMd. The present study used a multimodal approach to (1) identify a robust topographical organization of the right PMd by using connectivity-based parcellation (CBP) applied to a meta-analytic approach of task-related coactivation data (i.e. meta-analytic connectivity modeling, MACM5,6), and (2) examine whether the thus obtained parcellation pattern would be reproduced by CBP based on two other connectivity modalities: unconstrained functional (as reflected by RSFC) and structural as measured by PDT based on diffusion-weighted imaging (DWI). Methods A volume of interest (VOI) was defined by merging PMd activation sites from several meta-analyses serving as robust functional localizers of the PMd while excluding primary sensorimotor areas. MACM-CBP6 was performed using Brainmap database. RSFC-CBP and PDT-CBP were performed on distinct datasets to ensure independent parcellation7. RSFC-CBP was computed on RS data of 124 healthy subjects (age: 39.5 ± 11.5 yrs., 66 males) from the 1000BRAINS project8. The voxels’ time series (TS) were first cleaned from confounding effects using PCA denoising and global signal regression. RSFC was then computed by Pearson correlations between the TS of the VOI voxels and those of the rest of the brain. PDT-CBP9 was performed on DWI data of 20 healthy subjects (age: 18.5 ± .76, 10 males) using FSL. Several cluster solutions (k solution) were examined with k-means for MACM- and RSFC-CBP and spectral clustering for PDT-CBP. The choice of the k solution was driven by task-based functional data (MACM) based on three criteria: variation of information, percentage of deviants, and silhouette value6. Results The selected criteria jointly identified the 5-cluster (5k) solution as optimal across the range of functional studies from Brainmap database (Figure 1). Examination of stability across subjects following PDT-CBP further suggested that k=5 may be considered a local optimum within 2 ≤ k ≤ 6. This solution revealed a similar pattern of topographical organization across modalities (Figure 2) with a subdivision along both rostro-caudal and ventro-dorsal axes, including a rostral cluster lying mainly anteriorly to the PG, a central one at the intersection of the precentral sulcus and the superior frontal gyrus, a caudal one in the posterior part of the PG, a ventral one adjacent to ventral PM, and a dorsal one adjacent to the inter-hemispheric premotor areas. Discussion For the first time our study revealed that the PMd could be divided along two axes: rostro-caudal and ventro-dorsal. This is consistent with previous functional2 and microstructure studies10 in humans and non-human primates suggesting a rostro-caudal distinction and with a previous PDT-CBP of the (dorsal) precentral gyrus4 showing that it could be subdivided in the ventro-dorsal direction. Importantly, this topographical organization was found in the independent analysis of three different connectivity aspects: task functional, unconstrained functional and structural, each based on different datasets. In sum, different modalities consistently show that the PMd can be subdivided into 5 subregions organized along both rostro-caudal and ventro-dorsal axes, comprehensively integrating patterns previously revealed by different methods. [less ▲]

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See detailFaire preuve de réflexion éthique pour poser un acte professionnel : une compétence transversale développée tout au long du Master en logopédie
Martinez Perez, Trecy ULg; Leclercq, Anne-Lise ULg; Leroy, Sandrine ULg et al

Poster (2016)

Le code éthique de la profession constitue un point de départ pour guider les actes mais le professionnel de la santé doit régulièrement aller au-delà de celui-ci et faire preuve de réflexion pour ... [more ▼]

Le code éthique de la profession constitue un point de départ pour guider les actes mais le professionnel de la santé doit régulièrement aller au-delà de celui-ci et faire preuve de réflexion pour analyser les situations complexes au niveau moral qui peuvent survenir (Purtilo & Doherty., 2011). L’équipe enseignante du Master en Logopédie de l’Université de Liège (Belgique) a souhaité travailler cette compétence transversale chez les étudiants au cours des cinq années du Master en Logopédie à travers plusieurs dispositifs d’apprentissage complémentaires. Tout d’abord, au cours du Bachelier, l’étudiant est amené à découvrir le code éthique et déontologique de la profession, à identifier les principes de ce code dans une situation professionnelle ciblée puis dans une variété de situations professionnelles. Ensuite, au cours du Master, l’étudiant est amené à inclure une réflexion éthique dans les actes qu’il pose durant ses stages sur le terrain (en contexte monodisciplinaire puis en contexte multidisciplinaire), à discuter des principes dans un contexte d’intervision/supervision avec d’autres étudiants et un tuteur (pour un dispositif similaire en Sciences infirmières, voir Blomberg & Bisholt, 2015) et, finalement, à susciter une réflexion critique chez ses pairs sur une question éthique et déontologique. Ces dispositifs d’apprentissage et leur complémentarité, ainsi que les perspectives d’évaluation seront développés dans le poster. [less ▲]

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See detailIngénierie des ambiances urbaines: développement d'un dispositif pédagogique mixant approche numérique et créativité
Nguyen, Ngoc Luan ULg; Reiter, Sigrid ULg

Poster (2016)

Le présent poster décrit le dispositif pédagogique mis en œuvre pour accompagner les étudiants dans la conception et l’évaluation d’ambiances urbaines grâce à la combinaison d’un apprentissage par projet ... [more ▼]

Le présent poster décrit le dispositif pédagogique mis en œuvre pour accompagner les étudiants dans la conception et l’évaluation d’ambiances urbaines grâce à la combinaison d’un apprentissage par projet et de la modélisation numérique des projets développés à l’échelle du quartier. Cette activité de formation répond aux sept critères essentiels d’une situation-problème en apprentissage par projet. Ce poster résume l’expérience accumulée dans l’application de ce dispositif pédagogique innovant. [less ▲]

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See detailImpact of estetrol on breast cancer development, metastatic dissemination and angiogenesis
Gallez, Anne ULg; Gérard, Céline ULg; BLACHER, Silvia ULg et al

Poster (2016)

The increased risk of breast cancer and thromboembolism in women who take Hormone Replacement Therapy (HRT) currently is a major public health problem. The discovery of novel molecules with better safety ... [more ▼]

The increased risk of breast cancer and thromboembolism in women who take Hormone Replacement Therapy (HRT) currently is a major public health problem. The discovery of novel molecules with better safety profile would provide useful advances for patient care. Estretrol (E4) appears as a promising candidate for HRT. Indeed, in contrast to current treatment containing ethinyl estradiol or estradiol (E2), E4 has a minimal impact on liver cells activity supporting a decreased incidence on thromboembolic events. In preclinical studies, E4 has been effective against the main symptoms of menopause such as hot flushes, vaginal atrophy, and osteoporosis, from a starting dose of 0.3 mg/kg/day. The aim of this study was to define the impact of E4 on breast cancer development when it is used at concentrations effective for menopause symptom relief. Treatment of estrogen receptor (ER)-positive breast cancer-developing mice (MMTV-PyMT) with several concentrations of E4 has shown that 0.3 mg/kg/day E4 did not increase tumor development and metastasis dissemination. However, at 3mg/kg/day, E4 increased the growth of hormone-dependent tumors and their metastatic dissemination in ovariectomized and intact mice. This effect was similar to the one observed with E2 used at 0.08 mg/kg/day. In an in vivo model of ER-negative tumors, we observed that 3mg/kg/day E4 improved tumor growth by increasing angiogenesis, and subsequently decreasing necrosis and tumor hypoxia. In contrast, 0.3 mg/kg/day E4 did not induce any of these effects on ER-negative tumors and tumor microenvironment. In conclusion, we have shown that 0.3 mg/kg/day E4, already reported to prevent menopause symptoms, does not increase breast tumor growth, metastasis dissemination, and angiogenesis. However, similarly to E2, higher concentrations of E4 are pro-tumorous. These results support that E4, if it is used in strictly controlled clinical applications, could have no or only limited impact on breast cancer. [less ▲]

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See detailComparison between model simulations and observations of tracer transport using MRI in the root zone.
Vanderborght, Jan; Koch, Axelle; Haber-Pohlmeier, Sabine et al

Poster (2016)

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See detailGalectin-1 is involved in osteoclast biology
Muller, Joséphine ULg; Binsfeld, Marilène; DUBOIS, Sophie ULg et al

Poster (2016)

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See detailCystatin C standardization decreases assay variation and improves assessment of GFR
Ebert, N; DELANAYE, Pierre ULg; Shlipak, M et al

Poster (2016)

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See detailPhenotypic differentiation of native and introduced populations of Quercus rubra L.
Merceron, Nastasia ULg

Poster (2016)

Native to North America, Northern red oak (Quercus rubra) was introduced in Europe in the XVIIth century for ornamental and forestry purposes. This species is now widespread in European forests due to ... [more ▼]

Native to North America, Northern red oak (Quercus rubra) was introduced in Europe in the XVIIth century for ornamental and forestry purposes. This species is now widespread in European forests due to plantations and natural regeneration. In invasive herbaceous plants, introduced populations are often genetically different from native populations. However, this has been poorly investigated in exotic tree species. Our objective was to explore the phenotypic variation between native and introduced populations of Q. rubra and to test for adaptation to the new environmental conditions since the introduction. We used three progeny test gardens, in South-Western, Central and North-Eastern France, composed of 64 American and 77 European populations. The gardens were settled from 1980s and trees were monitored regularly for growth (diameter, height) and leaf phenology (budburst, coloration). For two years, we have monitored acorn production. Within each garden, data were analyzed using mixed analyses of variance; Qst indexes were calculated to evaluate genetic differentiation between populations. Overall, introduced populations presented higher trait values than native populations: growth rate was higher and spring phenology was advanced. Fruit set was higher in introduced trees, although depending of the year. Qst estimates clearly demonstrated the existence of a high genetic differentiation between native populations, for growth and phenology. Introduced populations presented a lower level of differentiation, significant for phenology, but not for growth. These results suggest several hypotheses: (i) introduced populations only represent a part of the global diversity existing in the native range (ii) populations have evolved since introduction under new environmental selective pressures (ii) populations were selected by man since introduction. These hypotheses are being investigated, notably through a molecular approach. [less ▲]

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See detailChanges in the structure and the composition of microtubules within supporting cells of the organ of hearing during development.
Renauld, Justine ULg; Freeman, Stephen ULg; Thelen, Nicolas ULg et al

Poster (2016)

The auditory organ is a highly specialized structure composed by specific cellular types. The sensory cells are characterized by stereocilia at their apex and are necessary for the sound perception. These ... [more ▼]

The auditory organ is a highly specialized structure composed by specific cellular types. The sensory cells are characterized by stereocilia at their apex and are necessary for the sound perception. These cells are supported by supporting cells which contain up to 3000 microtubules and are formed by 15protofilaments (15pf) instead of the canonical 13, a unique fact among vertebrates. It was shown that a β-tubulin isoform can specify the microtubule architecture, such as the expression of the Moth β2 in the Drosophila testes imposed the 16pf structure on the corresponding subset of Drosophila microtubules, which normally contain 13pf. To determine the role of these tubulins in the auditory organ and their possible involvement in the formation of the unusual 15pf microtubules of supporting cells, we studied the spatiotemporal localization of five -tubulin isotypes (β1 to 5) as well as acetyl-α-tubulin within the hearing organ during development in rodents. By using confocal microscopy, we showed that with the exception of the β3-tubulin isoform that was specific to nerve fibres, all the different β-tubulin isoforms and acetyl-α-tubulin were mainly present in the supporting cells. Contrary to β1-4-tubulins, we also found that the β5-tubulin isoform appeared only at a key stage of the postnatal development. By using transmission electron microscopy, we examined the fine structure of microtubules at an early and a late postnatal stage. Our TEM study indicated that these cells are composed by 13pf microtubules at P2, but by 15pf microtubules at P25. We revealed further that this developmental stage coincide with the formation of two separate bundles of microtubules from a unique one in these supporting cells. In conclusion, the architecture and composition of microtubules present in the supporting cells change during development of the organ of Corti. Further experiments are now required to determine if these changes are related to the appearance of β5-tubulin. [less ▲]

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See detailCharacterisation of a secondary carotenoid producer microalga of the genus Coelastrella
Corato, Amélie ULg

Poster (2016)

Some green microalgae synthesize secondary carotenoids as protecting agents under stress. These pigments have high value as feed supplement for aquaculture and as health products. The most promising ... [more ▼]

Some green microalgae synthesize secondary carotenoids as protecting agents under stress. These pigments have high value as feed supplement for aquaculture and as health products. The most promising pigment is astaxanthin, because of its antioxidant, antitumoral and anti-inflamatory properties. The most used natural source of this pigment is the microalga Haematococcus pluvialis. However this species grows slowly and lacks robustness for easy cultivation. Therefore, other species are investigated for astaxanthin production. Here, we identified a locally isolated strain as Coelastrella sp. that is a secondary carotenoid producer. [1] A known typical feature of this genus, that we could observed in the strain by scanning electron microcopy, is the presence of meridional ribs. [2] We analyzed the culture conditions and concluded that this strain grows both autotrophically and heterotrophically and is able of fast change in pigment composition under controlled stress conditions. Thanks to HPLC analyses, we determined that the strain accumulates a variety of secondary carotenoids, among which: astaxanthin, cantaxanthin and echinenone. Unidentified compounds will be further analyzed by mass spectrometry. [less ▲]

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See detailSemantic relatedness of the memoranda prevents older adults from benefitting from unitization
Delhaye, Emma ULg; Tibon, Roni; Gronau, Nurit et al

Poster (2016)

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See detailGenetic differentiation of native and introduced populations of Quercus rubra L
Merceron, Nastasia ULg

Poster (2016)

Native to North America, Northern red oak (Quercus rubra) was introduced in Europe in the XVIIth century for ornamental and forestry purposes. This species is now widespread in European forests due to ... [more ▼]

Native to North America, Northern red oak (Quercus rubra) was introduced in Europe in the XVIIth century for ornamental and forestry purposes. This species is now widespread in European forests due to plantations and natural regeneration. In invasive herbaceous plants, introduced populations are often genetically different from native populations. However, this has been poorly investigated in exotic tree species. Our objective was to explore the phenotypic variation between native and introduced populations of Q. rubra and to test for adaptation to the new environmental conditions since the introduction. We used three progeny test gardens, in South-Western, Central and North-Eastern France, composed of 106 American and European populations with 1-25 families per population. The gardens were settled from 1980s and trees were monitored regularly for growth (diameter, height) and leaf phenology (budburst, coloration). Since trees had reached sexual maturity, we have monitored acorn production for two years. Within each garden, data were analyzed using mixed analyses of variance; Qst indexes were calculated to evaluate genetic differentiation between populations. Overall, introduced populations presented higher trait values than native populations: growth rate was higher and spring phenology was advanced. Fruit set was higher in introduced trees, although depending of the year. Qst estimates clearly demonstrated the existence of a high genetic differentiation between native populations, for growth and phenology. Introduced populations presented a lower level of differentiation than native populations. These results suggest several hypotheses: (i) introduced populations only represent a part of the global diversity existing in the native range (ii) populations have evolved since introduction under new environmental selective pressures (ii) populations were selected by man since introduction. These hypotheses are being investigated, notably through a molecular approach. [less ▲]

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See detailA novel protocol for the design of artificial (β/α)8-barrel proteins
Martina, Cristina ULg; Figueroa Yévenes, Maximiliano ULg; Moretti, Rocco et al

Poster (2016)

The design of protein de novo is an emerging field in biochemistry, where artificial proteins are first designed in silico and then validated experimentally. This research, which rests mainly on our ... [more ▼]

The design of protein de novo is an emerging field in biochemistry, where artificial proteins are first designed in silico and then validated experimentally. This research, which rests mainly on our current understanding of protein structure, function, folding, stability and solubility, contributes to expand our knowledge of proteins in general. Our group has a long tradition in the design of artificial (β/α)8 -barrel proteins (called Octarellins). This fold is extremely interesting because it is widespread in nature (10% of the known proteins contain this fold) and in catalysis (it is present in 5/6 classes of enzyme). Here we present a protocol to design de novo (β/α)8-barrels with the more recent and best performing tools: Rosetta and Modeller (modelling softwares), and GROMACS (molecular dynamic simulations). First, 4000 artificial backbone structures were created with the use of modelling packages Rosetta and Modeller. 54 out of them were selected as targets for the following steps of sequence design and energy minimization (10 cycles), in order to find the best sequence to fit each target. More than 10000 different artificial sequences were created. Selection steps were performed in order to reduce the number of candidates for each target and the best ones were subjected to molecular dynamic simulation. Among this, 5 models were finally chosen for gene synthesis and experimental validation, and are currently being tested for expression in E. coli and preliminary purification. [less ▲]

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See detailThe effect of aging on associative memory for semantically-related word pairs
Folville, Adrien; Delhaye, Emma ULg; Bastin, Christine ULg

Poster (2016)

Detailed reference viewed: 43 (6 ULg)
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See detailThe Influence of the Perceived School Climate on Adolescents' Academic Achievement: Testing the Mediating Role of Intrinsic School Motivation
Vaillancourt, Marie-Claire; Blanchette-Luong, Vanessa; Véronneau, Marie-Hélène et al

Poster (2016)

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See detailSleep deprivation affects brain global cortical responsiveness
Gaggioni, Giulia ULg; Chellappa; Ly et al

Poster (2016)

Detailed reference viewed: 24 (2 ULg)
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See detailComparison of commercial membranes tailored as 3D in vitro cell models
Romano, Ilaria ULg; Tilkin, Rémi ULg; Hubaux, Roland et al

Poster (2016)

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See detailImpacts of wheel traffic on the physical properties of a Luvisol under reduced and conventional tillage
Saur, Marie-Laure ULg; Destain, Marie-France ULg; Roisin, Christian et al

Poster (2016)

Soil compaction is a complex mechanism which results in a decrease of soil porosity and an increase of soil strength. Such effects may reduce crop yield since they are harmful for root growth, germination ... [more ▼]

Soil compaction is a complex mechanism which results in a decrease of soil porosity and an increase of soil strength. Such effects may reduce crop yield since they are harmful for root growth, germination, mesofauna and bacterial life. Soil compaction may also reduce hydraulic conductivity which increases the risk of runoff, contamination of surface water, erosion and emission of greenhouse gases due to anaerobic processes. In the context of sustainable agriculture, it is crucial to characterise the impact of the agricultural techniques on the compaction state in the arable layer due to machine traffic. For this purpose, Soil samples were taken in a Luvisol at different depths, on plots under longterm reduced tillage (RT) and conventional tillage (CT). The impact of wheel traffic on the physical properties of the soils was also studied. The experimental approach consists in measuring traditional macroscopic soil properties such as bulk density and precompression stress, and combining them with pore size distribution obtained by mercury intrusion porosimetry. Automatic cone index measurements were initially performed to map the soil resistance and easily identify the sampling depths. The measurements revealed a plough pan at 30-cm depth under both CT and RT. Nevertheless, the subsoil under RT showed pieces of evidence of a natural regeneration process of the microporosity. The impact of wheel traffic was studied in RT and CT plots. It was shown that the passage of heavy machine such as beet harvester coupled to water content close to the optimum proctor is clearly unfavourable in terms of compaction. The measurements revealed large modifications of soil structure in the topsoil of CT, whereas the soil structure slightly changes through depth. However, the latter remains the more problematic case since the soil will not be loosened by tillage anymore, resulting in strongly compacted soil years after years. In addition to the experimental approach, numerical modelling was used in order to predict the soil compaction. A finite element method was used and the soil behaviour was modelled by an elastoplastic law (modified Cam-Clay model). The model parameters were calibrated from the experimental measurements. The simulations allowed to compare the porosity and the surface deformation after wheel traffic with the experiments. The variations of machine weight and tyre pressure were numerically studied and it was showed that the machine weight has an influence in the topsoil and the subsoil, whereas the tyre pressure affects only the topsoil. [less ▲]

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See detailProteomic landscapes of Pachycondila villosa ant venom by nano-scale chromatography and high resolution mass spectrometry
Cologna Takeno, Camila; Degueldre, Michel; Shibao, Priscilla et al

Poster (2016)

Introduction: It is estimated that the total number of molecules present in animal venoms is a collection of 40 million different compounds and, despite the efforts made, less than 0,01% of those ... [more ▼]

Introduction: It is estimated that the total number of molecules present in animal venoms is a collection of 40 million different compounds and, despite the efforts made, less than 0,01% of those compounds was identified and characterized to date. However, recent progresses in proteomic, in parallel with the advances of mass spectrometry have contributed to the study of those bio-libraries. The sensitivity improvement of these instruments allows the study of minimal amounts of sample still yielding a wealth of information. The present work aimed to perform a deep proteomic analysis of the venom from the ant Pachycondilyla villosa focusing on the de novo sequencing and the characterization of post translational modifications using high resolution mass spectrometers. Methods: The crude venom (0,5 ug) of P. villosa ants collected on Panga Natural Reserve (Uberlandia-Minas Gerais- Brazil) was diluted in 0,2% of formic acid and injected into a nanoACQUITY ULPC equipped with a monolithic PepSwift Capillary column 100µm x 25, hyphened to a Q Exactive Orbitrap mass spectrometer. The elution of the compounds was performed with a gradient of 3 to 50% of solution B in 80 minutes (A: H2O/FA 0.1%; B: ACN) at flow rate of 1 µL/min. All mass spectrometry analyses were performed in data dependent analysis (DDA) mode that automatically triggers the MS/MS experiments. The top 10 most intense peaks of each MS scan was fragmented by high-energy dissociation (HCD) and their corresponding MS/MS spectra were acquired. Preliminary data: Animal venoms are considered a rich source of biologically active compounds, which has been constantly selected and refined by the processes of natural evolution, in which each molecule is endowed with pharmacological properties highly valuable for scientific purposes. Despite the commitment, the exploration of these bio-libraries remains limited which might be related to the technological limitations that prevent full-scale investigation of these venoms. In addition, the conventional methods used to explore animal venoms are still time-consuming and require large amounts of samples, which restrict the studies for a few species. Unquestionably, the advances of proteomics and mass spectrometry instrumentations benefited a great deal the research on hymenoptera venom. Mostly due to their small size and therefore scarcely collected venom, this order has always been neglected and considered unfeasible to be studied through the known strategies. The present work represents the first report concerning the venom composition of P. villosa ant. The preliminary results already highlight the complexity of this venom, which showed to be composed by over 5000 different molecules. Most of those components fall into the 800- 4000 Da range, which is in agreement with other studies regarding ant´s venom composition. Most of the proteomics studies concerning ant venoms already revealed the presence of linear peptides below 5000 Da as major components. Those small peptides usually display antimicrobial activity and some of them hold additional insecticidal activity. Novel aspect: The results obtained already point out the biotechnological potential of P. villosa venom and highlight’s its complexity [less ▲]

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See detailModelling children’s mobility and school commuting: a review and key challenges for further research
Marique, Anne-Françoise ULg; Teller, Jacques ULg; Cools, Mario ULg

Poster (2016)

Children’s mobility and school travelling are relatively underdeveloped in transport research, especially when compared with commuting to work. Despite it is often argued that a profound analysis of ... [more ▼]

Children’s mobility and school travelling are relatively underdeveloped in transport research, especially when compared with commuting to work. Despite it is often argued that a profound analysis of school-travel patterns has the potential to generate many important insights that may impact transport-system policy and management, the modelling of children mobility, is still in an early stage of development and children are often only considered as constraints to adults’ mobility. In this paper, we argue that innovative modelling frameworks that were recently developed in the field of transportation could be adapted and applied to the mobility of children in order to develop both novel scientific insights and inform the development of policies aiming at increasing active and independent mobility of children, in a broader vision of sustainability. [less ▲]

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See detailInsights into a million-year-scale Rhenohercynian carbonate platform evolution through a multi-disciplinary approach: example of a GIvetian carbonate record from Belgium
Pas, Damien ULg; Da Silva, Anne-Christine ULg; Devleeschouwer, Xavier et al

Poster (2016)

In this study we formulate answers to three important questions related to Givetian carbonate records and their use for reconstructing million-year past palaeoenvironmental changes. First, we provide ... [more ▼]

In this study we formulate answers to three important questions related to Givetian carbonate records and their use for reconstructing million-year past palaeoenvironmental changes. First, we provide detailed illustrations of the fascinating depositional diversity that shaped a shallow reefal platform during the early- to late-Givetian in the Rhenohercynian Ocean; secondly we improve the sedimentological model of the Givetian carbonate platform in the Dinant Basin (Belgium) and thirdly we evaluate the application of magnetic susceptibility (MS) as a tool for long-term trends, correlation, and palaeoenvironmental reconstruction. These three goals are reached by making a detailed sedimentological, geophysical and geochemical study of the La Thure quarry. Petrographic analyses revealed eighteen microfacies which represent a carbonate platform evolution through early-late Givetian time, ranging from a homoclinal ramp to a discontinuously rimmed shelf and then a drowning shelf. These results allowed us to illustrate the fascinating environmental diversity that shaped one the largest carbonate platforms of Europe and provide an up to date model of the vertical and lateral development of the Belgian Givetian platform. Early-late Givetian La Thure sequence reveals five main depositional intervals, which could be correlated with the southern margin of the platform. These correlations allowed us to define the facies belts distribution, the major depositional changes that affected this platform and to highlight the Taghanic Event. Palaeo-redox proxies reveal a significant change in the oxygenation level, from oxygen-depleted to more oxic condition, between middle and late Givetian. This change is well-correlated with an increase in global temperature in the late Mid Devonian. Combination of MS and geochemistry demonstrates the inherent-parallel link existing between variation in MS values and proxies for siliciclastic input (such as Si, Al). Collected geochemical and MS data confirm that the La Thure can be considered as a key section for the internal shelf setting in the Rhenohercynian Ocean bordering Laurussia’s south-eastern margin. [less ▲]

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See detailIdentification d’indicateurs de la transition forestière en lien avec les impacts de la déforestation sur les socio-écosystèmes en Afrique centrale
Gillet, Pauline ULg; Vermeulen, Cédric ULg

Poster (2015, December 26)

La théorie de la transition forestière lie l’évolution du couvert forestier au temps (Mather, 1992). Dans la première phase, le couvert forestier est très dense. Il diminue ensuite avec l’augmentation de ... [more ▼]

La théorie de la transition forestière lie l’évolution du couvert forestier au temps (Mather, 1992). Dans la première phase, le couvert forestier est très dense. Il diminue ensuite avec l’augmentation de la densité de population qui pratique la défriche pour la production agricole et utilise le bois pour répondre aux besoins en énergie et en bois d’œuvre. Dans un troisième temps, l’économie se spécialise, l’agriculture s’intensifie et est pratiquée sur les terres les plus productives et le rôle de l’écosystème forestier dans l’économie diminue. L’abandon des terres les moins productives permet la recolonisation forestière visible sur la courbe de transition. La présente étude tente d’identifier et de proposer des indicateurs d’occupation spatiale permettant, sur base d’images de télédétection, de prévoir la position réelle d’un site sur la courbe de transition forestière. Ensuite, l’étude des socio-écosystèmes en lien avec la transition forestière permet de démontrer l’impact de la diminution du couvert forestier sur le fonctionnement des sociétés humaines. Nous nous sommes penchés sur différents aspects caractérisant les activités des populations locales dans trois sites d’étude situés sur un gradient de déforestation en Afrique centrale tels que la composition de repas et l’origine des aliments. On observe que la déforestation induit une diminution des composants issus des activités fortement liées à l’écosystème telles que la chasse, la pêche ou la collecte au profit de l’agriculture et de l’élevage. [less ▲]

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See detailOrganocatalytic coupling of carbon dioxide with epoxides: the unexpected booster effect of fluoroalcohols
Grignard, Bruno ULg; Gennen, Sandro ULg; Alves, Margot ULg et al

Poster (2015, December 19)

Valorising CO2 as a C1 feedstock for producing added value building blocks is seducing as it is a free and in exhaustive waste resulting from human activity. Carbon dioxide is a thermodynamically and ... [more ▼]

Valorising CO2 as a C1 feedstock for producing added value building blocks is seducing as it is a free and in exhaustive waste resulting from human activity. Carbon dioxide is a thermodynamically and kinetically stable molecule that can be converted into cyclic carbonates by coupling with epoxides. Cyclic carbonates are valuable products that find applications as solvents, electrolytes or as monomers for polyurethanes synthesis. Although the CO2/epoxide coupling reaction has been extensively studied, the development of organocatalysts that are highly efficient under mild experimental conditions still remains a challenge. Onium salts are the most common catalysts that show reasonable catalytic activity at high pressure (> 100 bars) and high temperature (> 100°C) only. Fortunately, the efficiency of these organocatalysts can be improved by addition of appropriate hydrogen bond donors activators (HBD). In this talk, we will report the development of a new highly efficient catalytic platform consisting in an onium halide salt combined with HBD activators for the fast and solvent-free synthesis of cyclic carbonates by coupling CO2 with epoxides. The cocatalytic effect of series of HBDs will be demonstrated by detailed online kinetics studies under pressure using Raman or IR spectroscopy. We will show that our new organocatalytic platform facilitates the fast conversion of epoxy groups into cyclic carbonates under mild experimental conditions, and can be easily implemented to the modification of epoxidized vegetable oils. The synergistic effects between HBDs and onium salt will be highlighted by a detailed mechanistic study of the reaction through DFT calculations. [less ▲]

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See detailHeat tracer and solute tests in an alluvial aquifer: field experiment and inverse modelling
Dassargues, Alain ULg; Klepikova, Maria; Jamin, Pierre ULg et al

Poster (2015, December 18)

Using heat as an active tracer in different types of aquifers is a topic of increasing interest. In this study, we investigate the potential interest of using heat tracer tests for characterization of a ... [more ▼]

Using heat as an active tracer in different types of aquifers is a topic of increasing interest. In this study, we investigate the potential interest of using heat tracer tests for characterization of a shallow alluvial aquifer. A thermal tracer test was conducted in the alluvial aquifer of the Meuse River, Belgium. The tracing experiment consisted in simultaneously injecting heated water and a dye tracer in a piezometer and monitoring the evolution of groundwater temperature and tracer concentration in the recovery well and in monitoring wells. To get insights in the 3D characteristics of the heat transport mechanisms the space-filling arrangement of observation wells was used. The breakthrough curves measured in the recovery well showed that heat transfer in the alluvial aquifer is slower and more dispersive than solute transport. Recovery is very low for heat while in the same time it is measured as relatively high for the solute tracer. This is due to the fact that heat diffusion is larger than molecular diffusion, implying that exchange between groundwater and the porous medium matrix is far more significant for heat than for solute tracers. Temperature breakthrough curves in other piezometers are contrasted with what would be expected in an ideal layered aquifer. They reveal strongly unequal lateral and vertical components of the transport mechanisms. The observed complex behavior of the heat plume was explained by the groundwater flow gradient on the site and heterogeneities of hydraulic conductivity field. By using numerical model of heat and flow coupled with pilot points inverse approach main preferential paths were characterized. [less ▲]

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See detailFirst Analysis of Martian Nightglow Seasonal Variations Observed by MAVEN's Imaging Ultraviolet Spectrograph
Stiepen, Arnaud ULg; IUVS team

Poster (2015, December 15)

We report results from a study of nitric oxide nightglow over the northern hemisphere of Mars during winter and southern hemisphere during equinox. We present observations of the nitric oxide δ and γ band ... [more ▼]

We report results from a study of nitric oxide nightglow over the northern hemisphere of Mars during winter and southern hemisphere during equinox. We present observations of the nitric oxide δ and γ band emissions between 190 and 270 nm by the Imaging UltraViolet Spectrograph on the MAVEN spacecraft. The emission reveals recombination of N and O atoms dissociated on the dayside of Mars, and is known to trace upper atmosphere hemispheric circulation patterns. We extend previous studies to higher latitudes, finding brighter emissions closer to the poles as predicted from global circulation models. Statistically significant variability suggests variation of the fluxes of N and O carried from the dayside thermosphere, as well as possible variations of the wind pattern in the nightside thermosphere and mesosphere. [less ▲]

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See detailEvaluating the performance of short-term heat storage in alluvial aquifer with 4D electrical resistivity tomography and hydrological monitoring
Robert, Tanguy; Paulus, Claire; Bolly, Pierre-Yves et al

Poster (2015, December 14)

In the context of energy demand side management (DSM), energy storage solutions are needed to stock energy during high production periods and recover energy during high demand periods. Among currently ... [more ▼]

In the context of energy demand side management (DSM), energy storage solutions are needed to stock energy during high production periods and recover energy during high demand periods. Among currently studied solutions, storing energy in the subsurface through heat pumps and/or exchangers (thermal energy storage) is relatively simple with low investment costs. However, the design and functioning of such systems have strong interconnections with the geology of the site which may be complex and heterogeneous, making predictions difficult. In this context, local temperature measurements are necessary but not sufficient to model heat flow and transport in the subsurface. Electrical resistivity tomography (ERT) provides spatially distributed information on the temperature distribution in the subsurface. In this study, we monitored, with 4D ERT combined with multiple hydrological measurements in available wells, a short-term heat storage experiment in a confined alluvial aquifer. We injected heated water (ΔT=30K) during 6 hours with a rate of 3 m³/h, stored during 3 days, and then we pumped it back to estimate the energy balance. We collected ERT data sets using 9 parallel profiles of 21 electrodes and cross-lines measurements. Inversion results clearly show the ability of ERT to delimit the thermal plume growth during injection, the diffusion and decrease of temperature during storage, and the decrease in size after pumping. Quantitative interpretation of ERT is difficult at this stage due to strong spatial variations of the total dissolved solid content in the aquifer, due to historical chloride contamination of the site. Energy balance shows that up to 75% of the energy can be easily recovered with an adapted strategy in the context of DSM. Short-term heat storage in alluvial aquifer is efficient and ERT is a valuable tool to image and estimate the temperature distribution in the subsurface. [less ▲]

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See detailINVESTIGATING MODEL DEFICIENCIES IN THE GLOBAL BUDGET OF ETHANE
Tzompa-Sosa, Z. A.; Keller, C. A.; Turner, A. J. et al

Poster (2015, December 14)

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See detailAnalyse de la répartition spatiale des restes fauniques du site éémien de Caours. Apport des systèmes d'information géographique.
Moreau, Gwénaëlle ULg

Poster (2015, December 12)

The Palaeolithic deposit of Caours, located in the Somme, is the only Eemian site in Northern Europe in interglacial context. This site show an incredible conservation of faunal remains spread out over a ... [more ▼]

The Palaeolithic deposit of Caours, located in the Somme, is the only Eemian site in Northern Europe in interglacial context. This site show an incredible conservation of faunal remains spread out over a large area and a recurrence Human occupation. That gave us a large amount of data about this period of Neanderthal history. We now questioning about the choice of this locality and the spatial organisation of Neanderthal. Then, spatial analysis using the Geographic Information System (GIS) appear to being a useful tool to answer it. We show the consequent availability of water, prey and tool raw material. Neanderthalians was opportunistic hunters of cervidae. There has also eat a heavier prey as aurochs and rhino by trapping or scavenging. Then Neanderthal of Caours butchering with tool made in-situ eating the meat and the marrow. [less ▲]

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See detailEvolution récente du trait de côte dans le Golfe de Guinée: Exemple du Togo et du Bénin (2000-2015)
Ozer, Pierre ULg; Hountondji, Yvon-Carmen; de Longueville, Florence

Poster (2015, December 10)

L’interface terre-mer est un environnement extrêmement fragile. De par le monde, les littoraux sont menacés par une multitude de facteurs parfois naturels et le plus souvent anthropiques. Ainsi, aux ... [more ▼]

L’interface terre-mer est un environnement extrêmement fragile. De par le monde, les littoraux sont menacés par une multitude de facteurs parfois naturels et le plus souvent anthropiques. Ainsi, aux perturbations occasionnées aux zones côtières par les infrastructures portuaires, les barrages, les prélèvements de sédiments à même la plage ou encore l’extension urbaine, s’ajoutent les conséquences des changements climatiques, dont l’élévation du niveau des océans. Nous proposons dans cet article d’évaluer la récente évolution du trait de côte au Togo et au Bénin où plusieurs études localisées démontrent que les plages sableuses connaissent des modifications (accumulation ou érosion) majeures ces dernières décennies. Dans le but d’avoir une vision globale de la dynamique côtière sur les 152 kilomètres de plages de ces deux pays d’Afrique de l’Ouest, nous utilisons les images à haute définition spatiale disponibles en open access sur Google Earth. Dans cette étude exploratoire, nous analysons le trait de côte par sections de 1 kilomètre entre 2002 et 2015 en estimant systématiquement l’évolution moyenne en mètre par an. Globalement, il appert que si certaines sections connaissent une accumulation, c’est uniquement dû au fait que celles-ci se trouvent en amont d’un obstacle majeur, comme la jetée d’un port. Les sections relativement stables sont uniquement liées à la présence de mesures de protection, comme des épis. Partout ailleurs, les littoraux subissent un processus érosif pouvant être impressionnant avec des reculs moyens pouvant dépasser les 10 mètres par an. [less ▲]

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See detailAnalytical developments to assess the crashworthiness of an offshore wind turbine jacket impacted by a ship
Pire, Timothée ULg; Le Sourne, Hervé; Buldgen, Loïc ULg et al

Poster (2015, December 10)

As the number of offshore wind farms is constantly increasing, impacts between ships and wind turbines is becoming a major concern. Nowadays, design offices use finite elements simulations to assess the ... [more ▼]

As the number of offshore wind farms is constantly increasing, impacts between ships and wind turbines is becoming a major concern. Nowadays, design offices use finite elements simulations to assess the crashworthiness of offshore supporting structures, which give accurate results but is time demanding. There is therefore a need for a faster method, especially during the pre-design stage. The purpose of this research is to develop analytical formulations, based on the so-called continuous elements method in order to compute the resistance of offshore wind turbine jackets when submitted to an impact. [less ▲]

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See detailDesign of new delivery systems for therapeutic proteins based on calcium carbonate microspheres
Ramalapa, Bathabile ULg; Crasson, Oscar ULg; Vandevenne, Marylène ULg et al

Poster (2015, December 10)

There exists a constant need for delivery systems that are biocompatible, offer bioactives protection from premature degradation and allow for targeted delivery and controlled release. Calcium carbonate ... [more ▼]

There exists a constant need for delivery systems that are biocompatible, offer bioactives protection from premature degradation and allow for targeted delivery and controlled release. Calcium carbonate (CaCO3) is one such system that has gained great favour for employment in the biomedical field due to possibilities of controlling size, morphology and crystalline forms of particles by tuning the synthesis conditions. CaCO3 has demonstrated ability to increase safety, stability and overall efficiency of protein therapeutics. The aim of the present work was to assess the significance of polysaccharide-protein complexes in enhancing the encapsulation of proteins in CaCO3 microspheres. A Chitin Binding Domain (ChBD), reported to have affinity for hyaluronic acid, was inserted on β-lactamase enzyme to develop a chimeric protein. The chimeric protein retained the activity of the enzyme and the binding properties and was encapsulated in CaCO3 microspheres by a super critical CO2 (ScCO2) process using hyaluronic acid as a templating agent. The particles were characterised in terms of size, zeta potential, morphology and protein loading. The results obtained confirmed the affinity of the ChBD to hyaluronic acid towards the production of stable, vaterite microparticles. Protein assays demonstrated that the ChBD enhanced the encapsulation of protein by up to 10 fold. Confocal images also suggested high encapsulation of the chimeric protein compared to native protein. Thus the production of polysaccharide-protein complexes seems effective in enhancing the encapsulation of proteins in CaCO3 microparticles using the ScCO2 process. Moreover this method will further be used to enhance encapsulation of therapeutic proteins such as growth factors for bone and cartilage regeneration. [less ▲]

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See detailCarte des risques de la baie de Tipaza (Algérie)
Nouri, Myriem ULg; Ozer, André ULg

Poster (2015, December 10)

Le littoral algérien a toujours été un territoire propice à l’établissement humain. En l’espace de 45 années, il a subi une urbanisation intense qui a développé une vulnérabilité multiple face aux ... [more ▼]

Le littoral algérien a toujours été un territoire propice à l’établissement humain. En l’espace de 45 années, il a subi une urbanisation intense qui a développé une vulnérabilité multiple face aux phénomènes naturels extrêmes. La zone d’étude, appelée dans ce travail « Baie de Tipaza », est l’un des espaces littoraux les plus évolutifs de l’aire métropolitaine d’Alger. Cette évolution lui a valu le titre de zone à très haute vulnérabilité dans l’espace algérien en termes de catastrophes naturelles. L’étude effectuée est une étude rétrospective, multiple et de constat. Son objectif est de présenter une carte des risques côtiers majeurs dans la zone-type. Les critères de jugement se basent sur des faits enregistrés et datés avec une étude géolocalisée grâce à des outils de télédétection et de système d’information géographique (SIG). Nous avons identifié trois (03) risques majeurs exerçant leur impact sur le territoire en étude : le risque sismique, les inondations et l’érosion du littoral. L’aléa sismique reste le plus dommageable car notre zone d’étude appartient au grand système actif de failles délimitant les plaques africaine et eurasiatique. Les séismes au large peuvent aussi causer des tsunamis. En ce qui concerne les inondations, l’irrégularité des pluies et leur soudaineté engendrent un caractère torrentiel au réseau hydrologique par des inondations de type « flash flood ». Quant à l’évolution littorale, la côte de Tipaza est globalement en recul permanent avec des variations entre -1.00 et - 2.70 m/an. Ces trois phénomènes exercent leur action sur un terrain de plus en plus urbanisé à très forte densité où 1.8% de la population algérienne est établie, avec un taux d’accroissement entre 1998 et 2008 de 2.1%. Cette pression démographique très importante se matérialise à travers des extensions urbaines non contrôlées et une évolution dirigée vers le littoral. La comparaison entre les images CORONA de 1967 et WORLDVIEW de 2010 montre une densification intense et continue de cette partie du littoral. Les résultats cités en amont, nous montrent l’ampleur de la vulnérabilité de la baie. Le risque sismique est permanent, il exerce un impact direct sur les constructions et induit des dégâts matériels et sociaux immédiats d’où la classification du site en « Zone III ». Les inondations se sont souvent produites suite à des événements ordinaires et saisonniers n’ayant rien de remarquables, mais accentuées essentiellement par l’urbanisation anarchique qui favorise une perméabilisation non contrôlée des sols, par la défaillance des réseaux d’assainissement et le gonflement des oueds dû à l’accumulation de décombres et de détritus surtout à leurs embouchures. Quant à l’érosion de la bande littorale, elle est causée par l’interruption du transit sédimentaire causée à l’amont par la présence de barrages qui bloquent les alluvions et par une surexploitation locale des sédiments de plages pour l’industrie du bâtiment. En outre, une urbanisation trop proche de la côte perturbe l’équilibre fragile du littoral. Ce travail limité à la baie de Tipaza a pour but de cartographier les données disponibles, il fait partie d’une étude de vulnérabilité de la zone urbanisée ou à urbanisation future de la bande côtière algérienne. Cette carte des risques permettra d’émettre des recommandations et des plans de gestion et sera un outil d’aide à la décision. [less ▲]

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See detailNitrous oxide fluxes by croplands: Towards a better understanding of emission mechanisms and dynamics
Lognoul, Margaux ULg; Broux, François ULg; SALERNO, Giovanni ULg

Poster (2015, December 10)

Nitrous oxide is a greenhouse gas that can be emitted by crops. Our poster summarizes the emission mechanisms and implied variables and presents preliminary results obtained with eddy covariance on winter ... [more ▼]

Nitrous oxide is a greenhouse gas that can be emitted by crops. Our poster summarizes the emission mechanisms and implied variables and presents preliminary results obtained with eddy covariance on winter wheat and automated dynamic closed chambers on maize. [less ▲]

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See detailThe ICOS Vielsalm Terrestrial Observatory: long term greehouse gas flux measurements
Hurdebise, Quentin ULg; De Ligne, Anne ULg

Poster (2015, December 10)

Presentation of the Vielsalm ICOS Terrestrial Observatory: site management, data available, data access, flux temporal dynamic and flux relation with climate variables.

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See detailImpact of shoreline changes on population in Cotonou, Benin
de Longueville, Florence; Hountondji, Yvon Carmen; Gemenne, François ULg et al

Poster (2015, December 10)

The coast of Cotonou (Benin) is affected by an intensive coastal erosion for several decades, mainly due to unsuitable port infrastructures and human activities. In the future, the process will very ... [more ▼]

The coast of Cotonou (Benin) is affected by an intensive coastal erosion for several decades, mainly due to unsuitable port infrastructures and human activities. In the future, the process will very likely be worsen by sea level rise as a consequence of global warming. In this study, we use a combination of very high resolution satellite images from Google Earth recorded in 2002, 2011, 2013 and 2014 and carry out field missions in September 2012, September 2013, July 2014 and February 2015 to assess the retreat of the coastline and to understand the dynamic of population in the risk area. Multi-temporal analyses of satellite images show that nearly 93 hectares of land (including 40 hectares off) were progressively eroded by the sea between 2002 and 2014 on the stretch of the first eight kilometers at the east of the Safiato groyne. This corresponds to an average coastline’s retreat of 115 meters in 13 years, with variations from 38 to 145 meters, depending on the location. Thanks to the comparison between the images of 2002 and 2014, we assess that around 765 houses disappeared by the encroachment of the sea over the distance of 8 km to the East of the Safiato groyne, of which 60 villas and about 705 makeshift houses (informal settlements). Well-off population leave the risk area when their houses are threatened and go inland, fishermen prefer to stay in the risk area to be close to their activities and precarious population have no financial and social capitals to migrate, they are trapped in the risk area. Other precarious population coming from somewhere else settle in the coastal area and grow the at-risk population. The use of intermediate images and the results of field works confirm a rapid process of settlement/destruction of makeshift houses in the coastal area. Poor people carry out simply short displacements in the risk area. There is an urgent need to secure these populations. Update and respect of urban planning regulations, good governance, cooperation with other countries and involvement of local communities are all factors that are expected to reach this objective. [less ▲]

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See detailLa traduction de l’humour dans la poésie orale peule du Cameroun
Oumarou Mal Mazou, Rachid ULg

Poster (2015, December 09)

Le poster présente le projet de thèse en cours de finalisation à l'Université de Liège

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See detailOn the LZ distance for dereplicating redundant prokaryotic genomes
Léonard, Raphaël ULg; Baurain, Denis ULg; Kerff, Frédéric ULg et al

Poster (2015, December 07)

The fast-growing number of available prokaryotic genomes, along with their uneven taxonomic distribution, is a prob- lem when trying to assemble broadly sampled genome sets for phylogenomics and ... [more ▼]

The fast-growing number of available prokaryotic genomes, along with their uneven taxonomic distribution, is a prob- lem when trying to assemble broadly sampled genome sets for phylogenomics and comparative genomics. Indeed, most of the new genomes belong to the same subset of hyper-sampled phyla, such as Proteobacteria and Firmicutes, or even to single species, such as Escherichia coli (almost 2000 genomes as of Sept 2015), while the continuous flow of newly discovered phyla prompts for regular updates. This situation makes it difficult to maintain sets of representative genomes combining lesser known phyla, for which only few species are available, and sound subsets of highly abundant phyla. An automated straightforward method is required but none are publicly available. The LZ distance, in conjunction with the quality of the annotations, can be used to create an automated approach for selecting a subset of represen- tative genomes without redundancy. We are planning to release this tool on a website that will be made publicly available. [less ▲]

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See detailAFM study of the penicillin receptor BlaR1 of Bacillus licheniformis
Mescola, Andrea ULg; Dauvin, Marjorie ULg

Poster (2015, December 03)

In presence of β-lactamines, some strains of B. licheniformis secret a β-lactamase that hydrolyses the antibiotic, making the bacteria resistant to penicillin. Staphylococcus aureus possesses a very ... [more ▼]

In presence of β-lactamines, some strains of B. licheniformis secret a β-lactamase that hydrolyses the antibiotic, making the bacteria resistant to penicillin. Staphylococcus aureus possesses a very similar system, allowing the expression of a β-lactamase in response to the presence of antibiotic outside the cell . In both strains, cells are able to sense the antibiotic in the medium through a membrane penicillin receptor BlaR1. Up to now, the 3D structure addressing the receptor in its entire form is not available, mainly due to low production yields and degradation. Here we show production, purification and reconstitution of the entire membrane protein in a lipid bilayer and a first AFM study of intra-molecular forces involved in the activation process of BlaR1. [less ▲]

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