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See detailTrouble de la reconnaissance de soi chez des personnes atteintes de la maladie d'Alzheimer
Moyse, Evelyne ULg; Bastin, Christine ULg; Salmon, Eric ULg et al

Poster (2014, June 12)

Introduction : Outre des difficultés de mémoire épisodique, la maladie d’Alzheimer est associée à une altération progressive du fonctionnement de la mémoire sémantique où les connaissances du passé ... [more ▼]

Introduction : Outre des difficultés de mémoire épisodique, la maladie d’Alzheimer est associée à une altération progressive du fonctionnement de la mémoire sémantique où les connaissances du passé lointain sont mieux préservées que les connaissances acquises récemment. De plus, il a été rapporté que ce type de perte peut aussi se produire pour la reconnaissance de son propre visage. Une étude décrivait le cas d’une femme atteinte de la maladie d’Alzheimer à un stade avancé qui était incapable de se reconnaître sur des photographies prises dans un passé récent mais qui avait peu voire pas de difficultés à se reconnaître sur des photographies prises pendant les deux premières décennies de sa vie adulte. Cependant, la description d’une seule étude de cas pourrait être vue comme anecdotique. Objectifs : L’objectif de cette étude est d’évaluer si ce type de difficultés peut s’observer dans un plus large échantillon de patients. Pour ce faire, des patients à des stades légers à modérés de la maladie sont comparés à des sujets âgés sains sur une tâche de reconnaissance de visages (soi, familier, inconnu) appartenant à différentes périodes de vie (20 ans jusqu’à récemment). Résultats : Au stade léger, les patients présentaient des difficultés uniquement pour reconnaître le visage d’une personne familière alors qu’au stade modéré de la maladie, ces difficultés s’observaient à la fois pour le visage familier et le propre visage. De plus, comparés aux sujets âgés sains, les patients modérés avaient des difficultés pour se reconnaître sur des photos récentes, alors qu’aucune différence n’était observée pour les autres périodes de vie. Par contre, aucune différence entre les patients légers et leurs sujets contrôles n’était observée selon l’âge des visages. Par ailleurs, l’analyse des temps de réaction montraient que ces deux groupes de participants étaient plus lents pour reconnaître les photos anciennes par rapport aux photos récentes. Conclusion : La présente étude révèle que les difficultés de reconnaissance des visages évoluent avec l’avancement de la maladie, avec des difficultés qui touchent uniquement la reconnaissance de visages familiers au stade léger de la maladie mais qui s’étendent au propre visage au stade modéré. De plus, une perte graduée dans le temps de la reconnaissance de soi est observée chez les patients modérés (moindre reconnaissance de son visage récent) mais pas chez les patients légers. Au contraire, un ralentissement de la reconnaissance des photos anciennes par rapport aux photos récentes était constaté chez les patients légers ainsi que chez leurs sujets contrôles. Deux hypothèses sont avancées pour expliquer ce phénomène. Premièrement, les photos anciennes provoqueraient une réaction de surprise et par là, augmenteraient le temps de réponse. La seconde hypothèse postule plutôt une difficulté d’accès aux représentations antérieures de soi et de son proche. [less ▲]

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See detailGround-based transmission spectrum of WASP-80 b, a gas giant transiting an M-dwarf
Delrez, Laetitia ULg; Gillon, Michaël ULg; Lendl, Monika ULg et al

Poster (2014, June 09)

We present here some results from our ground-­based multi-­object spectroscopy program aiming to measure the transmission spectrum of the transiting hot Jupiter WASP-80b using the VLT/FORS2 instrument ... [more ▼]

We present here some results from our ground-­based multi-­object spectroscopy program aiming to measure the transmission spectrum of the transiting hot Jupiter WASP-80b using the VLT/FORS2 instrument. WASP-­80b is a unique object as it is the only known specimen of gas giant orbiting an M-dwarf that is bright enough for high SNR follow-­up measurements. Due to the nature of its host star, this hot Jupiter is actually more `warm' than `hot', with an estimated equilibrium temperature of only 800K. It is thus a prime target to improve our understanding of giant exoplanet atmospheres in this temperature range. [less ▲]

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See detailEffects of tillage practices and crop residue exportation on earthworm communities and soil physico-­chemical properties in silt loam arable soil (Belgium)
Lemtiri, Aboulkacem ULg; Colinet, Gilles ULg; Alabi, Taofic ULg et al

Poster (2014, June 08)

Earthworms are known to play integral roles in soils, and are often referred to as vital soil and ecosystem engineers due to their capacity to influence a wide range of chemical, physical, and biological ... [more ▼]

Earthworms are known to play integral roles in soils, and are often referred to as vital soil and ecosystem engineers due to their capacity to influence a wide range of chemical, physical, and biological properties of soil environments. Therefore, it is important to understand how earthworm communities are impacted by tillage systems and crop management practices. In the present study, earthworm and soil samples were collected from wheat cultivated fields in Gembloux, Belgium under the following four experimental treatments: (1) conventional tillage with crop residues left in the soil (CT/IN); (2) conventional tillage with crop residues removed from the field (CT/OUT); (3) reduced tillage with crop residues left in the soil (RT/IN); and (4) reduced tillage with crop residues removed from the field (RT/OUT). The different tillage systems were applied for four consecutive years prior to the initiation of the current study. Results indicated soil compaction was significantly higher in RT compared with CT up to a depth of 6–49 cm. Significant differences were not detected between residue incorporation depth systems, where results showed mean earthworm abundance was respectively 182.25 and 180 individuals.m-2 in CT and RT. Mean earthworm biomass was similarly not significantly different between CT and RT, where results were respectively 48.52 and 57.27 g.m-2. However, a significant difference was observed between IN and OUT treatments, suggesting the exportation of wheat residues will limit earthworm abundance and biomass in CT and RT plots. Data showed high representation of the endogeic earthworm ecological category, notably N. c. caliginosus regardless of treatment. Despite tillage system and exportation of crop residues, N. c. caliginosus, L. terrestris, and A. r. rosea exhibited high abundance, indicating tolerance to soil environmental conditions. For each depth, measures of soil physico-chemical properties showed significant differences among treatments. Furthermore, soil chemical property attributes were significantly higher in the first soil centimetres compared to lower soil layers. These results were attributable to earthworm activity and wheat residues, suggesting earthworms contributed to nutrient dynamics, particularly at increased soil depths. Overall, the results emphasise the influence of exportation of crop residues on earthworm community and also, the important influence of earthworm activity on soil physico-chemical properties change, processes which are closely linked. [less ▲]

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See detail[18F]UCB-H AS A NEW PET RADIOTRACER FOR SYNAPTIC VESICLE PROTEIN 2A
Bahri, Mohamed Ali ULg; Bastin, Christine ULg; Aerts, Joël ULg et al

Poster (2014, June 06)

Synaptic vesicle protein 2A (SV2A) is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is shown ... [more ▼]

Synaptic vesicle protein 2A (SV2A) is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is shown, for example, by the fact that it is a binding site and the primary mechanism of levetiracetam. Levetiracetam is an antiepileptic drug which has recently been suggested to reduce synaptic deficits in a mouse model for Alzheimer’s disease and to improve cognition in patients with amnestic mild cognitive impairment. We here aimed to investigate the cerebral distribution of [18F]UCB-H, a fluorine-18 radiolabelled PET imaging tracer, which has a high affinity with the SV2A. [18F]UCB-H was radiosynthesized under GMP conditions. Dynamic PET data of the head of four healthy volunteers were acquired over 100 minutes after injection of 170.4 ± 24.9 MBq of [18F]UCB-H. The arterial input function was obtained by blood sampling during the dynamic PET acquisition. The analysis of the blood data reveled a consistent amount of [18F]UCB-H in whole blood and plasma which indicates a very low degree of binding of the tracer to the red blood cells. The unchanged fraction of [18F]UCB-H in plasma showed a bi-exponential behavioral decrease with a starting fraction of 92% of the injected amount of the tracer, measured at 3 min post injection. This fraction decreased to about 50% at 10 min post injection. The [18F]UCB-H PET data showed a high and rapid uptake in the grey matter structures, matching the known ubiquitous distribution of the SV2A in the brain. The kinetics of the tracer in the brain was characterized by an initial high uptake phase followed by rapid washout allowing the standard compartmental modeling (1-tissue compartment, 2-tissue compartment, and Logan graphical analysis). The three models gave consistent results. The two-tissue compartment model fitted the experimental data best and provided a total distribution volume of the [18F]UCB-H in the brain greater than 7 mL/cm3 and a specific distribution volume around 3 mL/cm3. Our results suggest that [18F]UCB-H is a good candidate as radiotracer for brain SV2A proteins and could be used for human studies. In the future, SV2A modifications might be assessed in neurological pathologies such as Alzheimer’s disease. [less ▲]

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See detailComparison between wind speed observed at 100m height and wind speeds simulated by the WRF and MAR models
Doutreloup, Sébastien ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg et al

Poster (2014, June 06)

In the context of FLEXIPAC project funded by "RELIABLE" program of Walloon Region (Belgium), the Laboratory of Climatology and Topoclimatology (LCT) of the University of Liège (Belgium) aims to adjust the ... [more ▼]

In the context of FLEXIPAC project funded by "RELIABLE" program of Walloon Region (Belgium), the Laboratory of Climatology and Topoclimatology (LCT) of the University of Liège (Belgium) aims to adjust the WRF regional model (v.3.4.) forced by ERA-Interim model. Our analysis shows that wind speeds at 100m height simulated by WRF are systematically overestimated compared to wind speeds extracted from wind productions of two wind farms. In order to identify this problem, four comparisons were performed in this contribution. Firstly, we compare WRF model with reanalysis based forcing model. Secondly, we compare two WRF simulations, where one of them has a more precise spatial resolution. Thirdly, we smooth WRF outputs in time (6-hr running mean) in order to study the accuracy of the 30-min variability generated by WRF model. Finally, we comp compare the WRF model with the MAR (v3.3.) regional model using the same forcing at its lateral boundaries. This last one seems to suggest that the MAR model better simulates wind speeds at 10m and at 100m than WRF model and then that wind speed underestimation by WRF is well linked to the WRF physics itself. [less ▲]

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See detailDesign and synthesis of high-affinity ligands of AMPA receptors and study of their Fluorine-18 radiolabeling
Deverdenne, François ULg; Goffin, Eric ULg; Plenevaux, Alain ULg et al

Poster (2014, June 05)

The AMPA subtype of glutamatergic receptors is the main actor in the excitatory neurotransmission in the mammalian central nervous system. These receptors are involved in the expression and the ... [more ▼]

The AMPA subtype of glutamatergic receptors is the main actor in the excitatory neurotransmission in the mammalian central nervous system. These receptors are involved in the expression and the maintenance of the long-term potentiation, a phenomenon closely linked to cognitive and memorization processes. Based on experimental data collected in recent years, the use of AMPA potentiators seems to be an interesting approach in the treatment of cognitive deficits (e.g. Alzheimer disease), schizophrenia or depression. Such AMPA signal potentiation could be mediated by positive allosteric modulators (PAMs) of the AMPA receptors, a class of compounds able to produce a fine signal tuning in the presence of the endogenous ligand in the synapse, providing less toxicity than direct agonists. With this approach, the laboratory of Medicinal Chemistry of Liège university developed many series of AMPA potentiators , among which 1,2,4-benzothiadiazine 1,1-dioxides (BTDs). In order to better understand the in vivo mapping of AMPA receptors and its evolution in neurological diseases, the present work aims at developing the design and the synthesis of BTDs positive allosteric modulators radiolabeled with a fluorine-18 atom. Based on previously synthesized series in this field, we investigate the synthesis of a new class of high-affinity AMPA potentiators characterized by the presence of a fluorine atom at selected positions on the structure of the AMPA potentiators. Thanks to in vitro pharmacological evaluations, we will further determine the best candidates for their fluorine-18 radiolabeling. [less ▲]

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See detailA PREFERENTIAL FOLDED CONFORMATION OF SOME BIS-(8-ISOPROPYL-ISOQUINOLINIUM) DERIVATIVES EXPLAINS STEREOSELECTIVE REDUCTION BY SODIUM BOROHYDRIDE
Dilly, Sébastien ULg; Badarau, Eduard; Dufour, Fabien et al

Poster (2014, June 05)

Small conductance Ca2+-activated K+ (SK) channels play a role in modulating the firing rate and the firing pattern of neurons [Waroux, Eur J Neurosci, 2005, 22, 3111]. A blockade of these targets could be ... [more ▼]

Small conductance Ca2+-activated K+ (SK) channels play a role in modulating the firing rate and the firing pattern of neurons [Waroux, Eur J Neurosci, 2005, 22, 3111]. A blockade of these targets could be useful for the treatment of cognitive dysfunction, neuronal hyperexcitability or dopamine related disorders [Liégeois, Curr Med Chem, 2003, 10, 625]. At the peripheral level, the inhibition of these channels was demonstrated to prevent and terminate atrial fibrillation [Diness, Circ Arrhythm Electrophysiol, 2010, 3, 380]. Moreover, SK channels might represent potential targets for a new class of anticancer agents due to their involvement in breast cancer cell migration [Potier, Mol Cancer Ther, 2006, 5, 2946]. So far, available blockers are not suitable CNS pharmacological tools being either peptides or small molecules with permanent positive charges [Liégeois, Curr Med Chem, 2003, 10, 625; Graulich, J Med Chem, 2007, 50, 5070; Badarau, Bioorg Med Chem Lett, 2011, 21, 6756]. Therefore, symmetrical bis-isoquinolinium compounds have subsequently been transformed to 1,2,3,4-tetrahydroisoquinoline analogues by using sodium borohydride leading to a diastereoisomeric mixture (figure 1) in order to obtain potential CNS-penetrating agents [Graulich, Bioorg Med Chem Lett, 2008, 18, 3440; Neny, Proceedings of the 12th International Conference on In Vivo Methods, Vancouver, Canada, 2008, 267; Koulchitsky, Acta Physiologica, 2009, 195, 670]. Resolution of these mixtures and characterization of the corresponding stereoisomers [Wouters, Eur J Med Chem, 2010, 45, 3240] are necessary before further biological evaluation. In a series of 8- isopropyl analogues, chiral resolution failed for the analogues with propyl and m-xylyl linkers since two and one peaks, respectively, were detected [Nistor, J Pharm Biomed Anal, 2013, 74, 273]. Could these results be explained by an ineffective resolution or would another phenomenon be involved? Further analysis using chiral chromatography, mass spectroscopy and circular dichroism of a sample of the propyl analogue revealed that it is a racemic mixture. X-ray cristallography and conformational analysis indicated a folded conformation of the propyl and m-xylyl analogues (figure 2) responsible for a stereoselective attack of the borohydride reagent during the reduction step. Additional 1H-NMR investigations support structural features detected by theoretical analysis. [less ▲]

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See detailFunctional study of the Ser/Arg-rich splicing factor SRSF5a during zebrafish embryonic development
Joris, Marine ULg; Muller, Marc ULg; Motte, Patrick ULg

Poster (2014, June 05)

Nuclear pre-mRNA splicing is a key process regulating gene expression in eukaryotes. Splicing consists in the removal of introns and the joining of exons within a dynamic macromolecular complex called the ... [more ▼]

Nuclear pre-mRNA splicing is a key process regulating gene expression in eukaryotes. Splicing consists in the removal of introns and the joining of exons within a dynamic macromolecular complex called the spliceosome, which consist of five small nuclear ribonucleoproteins (snRNPs) and numerous non snRNPs proteins (1). Amongst these non snRNPs proteins, the SR proteins family constituted an important group of splicing factors that are involved in constitutive and alternative splicing (2,3). SR proteins are structurally related as they are characterized by one or two RNA-recognition motifs (RRMs) in N-ter and a C-terminal domain enriched in dipeptide Ser/Arg. Phylogenetic inference using the RRM domain allowed us to identify 13 encoding genes for SR proteins in the vertebrate model organism, Danio rerio. The Zebrafish is increasingly recognized as a powerful model for the study of vertebrate embryonic development in a physiological context. The roles of SR splicing factors during animal cell differentiation and development are largely unknown. The aim of the present research is to investigate SR proteins functions during zebrafish development by using molecular and genetic approaches. In this study, we investigated the role of the SR splicing factor SRSF5a. The expression profile was determined by in situ hybridization at 24, 48 and 72 hours post-fertilization and showed SRSF5a expression mainly in brain, retina and pharyngeal arches at these stages. Furthermore, SRSF5a knock-down by morpholinos microinjection strongly suggests an important role of this specific splicing factor during eyes and brain development. In order to gain insight into the molecular function of SRSF5a, we analysed control and morphant transcriptomes using high throughput RNA sequencing. Finally, we use a complementary approach to morpholinos and generate SRSF5a mutant fishes using TALENs (Tal effector nucleases)(4,5). 1. Wahl MC, Will CL, & Luhrmann R (2009) The spliceosome: design principles of a dynamic RNP machine. Cell 136(4):701-718. 2. Long JC & Caceres JF (2009) The SR protein family of splicing factors: master regulators of gene expression. Biochem J 417(1):15-27. 3. Graveley BR (2000) Sorting out the complexity of SR protein functions. RNA 6(9):1197-1211. 4. Moore et al. (2012) Improved Somatic Mutagenesis in Zebrafish Using Transcription Activator-Like Effector Nucleases (TALENs). Plos One 120(1):1-12. 5. Cade et al (2012) Highly efficient generation of heritable zebrafish gene mutations using homo- and heterodimeric TALENs. Nucleic acid research Vol 40, No 16:8001-8010. [less ▲]

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See detailApproche lexicométrique des controverses climatiques
Scotto d'Apollonia, Lionel; Luxardo, Giancarlo; Piet, Grégory ULg

Poster (2014, June 05)

D’un point de vue historique, les controverses climatiques prennent racine à la fin du XIXe siècle et se sont déployées tout au long du XXe siècle. Elles prennent toutefois une tournure plus politique, en ... [more ▼]

D’un point de vue historique, les controverses climatiques prennent racine à la fin du XIXe siècle et se sont déployées tout au long du XXe siècle. Elles prennent toutefois une tournure plus politique, en ce début de XXIe siècle, en ce sens que le débat climatique « se priorise » dans les agendas politiques des Etats européens, de manière générale. Si les études sur les controverses climatiques tendent, certes, à se développer de plus en plus actuellement, l’approche linguistique demeure peu investie par rapport au potentiel analytique qu’elle pourrait apporter à la recherche sur le sujet. L’une des rares études lexicométriques concernant le climat est celle réalisée par Lamria Chetouani dont le corpus de textes s’étend de 1989 à 1990. Il faut aussi prendre en compte les travaux de Francis Chateauraynaud, qui a entrepris une démarche destinée au traitement des controverses s'appuyant sur un ensemble de techniques : la socio-informatique. Inscrit dans un cadre d’analyse socioépistémique des controverses socioscientifiques et en se basant sur un corpus de textes choisis autour de la période 2009 - 2010, notre article propose donc d'associer une analyse socio-informatique des controverses climatiques avec une utilisation d'outils lexicométriques. En nous concentrant sur le traitement discursif de quelques notions-clés, notamment l'incertitude et le risque, nous cherchons à croiser les résultats fournis par la lexicométrie (logiciel Lexico) avec ceux fournis par la socio-informatique (logiciel Prospero). En conclusion, nous ouvrons un espace de discussion sur les modes opératoires permettant d'articuler les deux approches. [less ▲]

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See detailRelations between negative symptomatology and executive measures in schizophrenia.
Laloyaux, Julien ULg; Guettafi, Yassine; Dessart, Gregory et al

Poster (2014, June 03)

Introduction: Negative symptomatology and cognitive impairments are core features of persons diagnosed with schizophrenia that have a major negative impact on everyday life functioning. Further, some ... [more ▼]

Introduction: Negative symptomatology and cognitive impairments are core features of persons diagnosed with schizophrenia that have a major negative impact on everyday life functioning. Further, some authors (Konstantakopoulos et al., 2011) have suggested that negative symptoms and executive functions might represent different manifestations of the same syndrome, but this relation remains poorly understood. Objective: The objective was to explore relations between negative symptomatology (and in particular apathy) and executive functions in persons diagnosed with schizophrenia. Method: Twenty-seven individuals diagnosed with schizophrenia were evaluated with an extensive executive battery in addition to several measures of negative symptomatology (including specific measures of apathy) and real world functioning. Results: Results revealed that apathy was significantly related to measures of initiation (i.e. verbal fluency) and everyday life functioning. Moreover, more general measures of negative symptomatology were significantly related to multitasking abilities and cognitive flexibility. Discussion: In this study, we assessed the relations between negative symptomatology and executive measures. The results confirmed the links between these constructs, thus suggesting a common neural substrate. Conclusion: Based on results from the present study, executive dysfunctions and negative symptomatology may be seen as representing different manifestations of the same syndrome. [less ▲]

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See detailComparison of Indicators to Evaluate the Resilience of Lab Scale Continuously Stirred Anaerobic Reactors Submitted to Biological Dysfunctions
Lemaigre, Sébastien; Adam, Gilles ULg; Goux, Xavier et al

Poster (2014, June 02)

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See detailBacteria, bonds between classical karsts and karsts in silicated non carbonated rocks ?
Willems, Luc ULg

Poster (2014, June)

For several years, similar karsts to those found in the limestone have been observed in various silicated non-carbonated rocks. Several morphological arguments show that a complete dissolution of rocks is ... [more ▼]

For several years, similar karsts to those found in the limestone have been observed in various silicated non-carbonated rocks. Several morphological arguments show that a complete dissolution of rocks is necessary to explain the formation of some caves and other related forms independently of hydrotermalisme phenomena. However, the physico-chemical processes generally considered do not provide a satisfactory explanation to this dissolution. Bacterial activity found deep in many lithologies provides a solution to this apparent contradiction. [less ▲]

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See detailInhibition of PDH Kinase as a new therapeutic target for Age-related Macular Degeneration (AMD)
Arslan, Deniz ULg; Pirotte, Bernard ULg; De Tullio, Pascal ULg et al

Poster (2014, June)

Metabolomics is one of the most recent technologies in the world of Omics sciences. It aims at studying metabolome, which is composed of small molecular weight organic molecules (called metabolites) of a ... [more ▼]

Metabolomics is one of the most recent technologies in the world of Omics sciences. It aims at studying metabolome, which is composed of small molecular weight organic molecules (called metabolites) of a cell, an organism or a biological system. This approach gives rise to a growing number of applications in many areas, such as biomarkers discovery, clinical studies, drug efficacy and toxicity evaluation, diagnostic tools, quality control. One of the most interesting features of metabolomics is its capability to extract biochemical information reflecting biological events and then to be a powerful tool in the knowledge of the aetiology of some pathologies. Indeed, it is clear that every disease could alter more or less drastically the metabolic profile of the patients. Then a metabolomics approach could highlight the biochemical pathways affected and could allow the identification of new putative therapeutic strategies or targets that could be useful in a new drug discovery strategy. As proteomics, metabolomics approach represents a new and powerful tool for Medicinal Chemistry. Age-related Macular Degeneration (AMD) is a leading cause of vision loss in the western world among people aged 50 or older. 90% of all vision loss due to AMD results from the exudative form, which is characterized by choroidal neovascularization (CNV). Age-related changes that induce pathologic CNV are incompletely understood. A successful application of anti-VEGF approaches in the clinic is obviously a turning point in AMD treatment. Nevertheless, despite such important advances, critical issues remain to be addressed. To better understand the aetiology of this pathology, we used and improved a murine model of laser-induced choroidal neovascularization and applied a 1H NMR metabolomics study. This approach leads to the emergence of different putative biomarkers and to the validation of the CNV model for an experimental study of AMD. Among these “biomarkers”, lactate appears to be clearly involved in the development of AMD. The modulation of their plasma concentration by treatment of the animals with synthetic compounds and more specifically Pyruvate DesHydrogenase Kinase inhibitors (PDHK) significantly decrease the impact of laser induced CNV. Starting from these results, the development of new PDHK inhibitors could open the way to innovative treatment opportunities in AMD disease. [less ▲]

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See detailInvestigation of differential virus transmission efficiency in aphid strains: from biological to proteomic assays
Bosquée, Emilie ULg; Francis, Frédéric ULg

Poster (2014, June)

Aphids are well known for their variable efficiency in virus transmission to host plant. Not only aphid species but also aphid strain is an important factor to consider in the plant-aphid-virus ... [more ▼]

Aphids are well known for their variable efficiency in virus transmission to host plant. Not only aphid species but also aphid strain is an important factor to consider in the plant-aphid-virus interactions. In order to investigate these relations, different approaches should be developped from biological observations assessing the virus transmission efficiency to molecular tasks to better know the involved mechanisms in the aphid vector. After a period of virus acquisition on an artificial diet (depending on the kind of transmission, permanent or non permanent ways), the virus transmission rate were assayed and followed by the determination of the presence of virus in the aphid by PCR or immudetection. The aphids were then collected to investigate the variation of aphid proteome and potential involvement in virus interactions. Changes in protein expressions were investigated using a 2D-DIGE approach comparing most and least efficient aphid strains selecting different aphid – virus models (PVY and PLRV in potato, BYDV in wheat, CMV on tobacco) . The proteome changes were analysed using the samespot software. Protein spots with significant up- and down expressions were then mechanically picked, trypsin digested and analysed by Maldi-Tof-Tof. Significantly changed proteins were classify according to metablic pathways and biological functions. Interesting proteins found to probably interact with virus were not only detected from aphid but also from related bacterial symbionts. Theses results were discussed in order to better understand virus – vector relations and potentially promote new ways to control virus transmitted by hemipteran pest. [less ▲]

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See detailSTUDIO in vitro DEI PARAMETRI DI COINFEZIONE E SUPERINFEZIONE CHE INFLUENZANO LA RICOMBINAZIONE NEI NOROVIRUS
Di Felice, Elisabetta; Ceci, Chiara; Zonta, William ULg et al

Poster (2014, June)

I norovirus (NoV) sono piccoli virus (38-40 nm) a RNA monocatenario sprovvisti di envelope appartenenti alla famiglia Caliciviridae. I NoV attualmente vengono riconosciuti come una delle più importanti ... [more ▼]

I norovirus (NoV) sono piccoli virus (38-40 nm) a RNA monocatenario sprovvisti di envelope appartenenti alla famiglia Caliciviridae. I NoV attualmente vengono riconosciuti come una delle più importanti cause di gastroenterite acute di origine non batterica nell'uomo coinvolgendo tutte le classi di età e soprattutto contesti comunitari. I meccanismi molecolari che influenzano l'evoluzione dei NoV sono l'accumulo di mutazioni puntiformi e la ricombinazione. L’obiettivo sarà quello di dimostrare che la ricombinazione è un evento che può essere influenzabile dall’impiego di diversi parametri di coinfezione/superinfezione. In letteratura, gli studi sugli eventi ricombinanti che caratterizzano i NoV umani risultano piuttosto limitati a causa dell'assenza di un substrato cellulare che ne permetta la replicazione in vitro. Nel presente lavoro è stato sviluppato un modello sperimentale basato sull’impiego dell’unico NoV, il norovirus murino (MNV), in grado di replicare su substrato cellulare. A tal fine monostrati di cellule RAW264.7 sono stati coinfettati e superinfettati con due ceppi di MNV (CW1 e WU20) utilizzando diversi indici di molteplicità (MOI) e differenti tempi di infezione. I surnatanti sono stati collezionati a 24 e 48 ore post-infezione e quindi sottoposti a metodo delle placche. All’interno della popolazione virale risultante da tale coinfezione/superinfezione, 36 cloni per ciascuna condizione sono stati selezionati e purificati dalle placche e, successivamente, utilizzati per infettare nuovi monostrati cellulari di RAW264.7. Il monitoraggio degli eventi ricombinanti è stato eseguito mediante PCR e Real-Time PCR dopo estrazione dell'RNA virale e retrotrascrizione, impiegando due set di primer in grado di amplificare le regioni site all’estremità iniziale di ORF1 e all’estremità terminale di ORF3. I risultati che permetteranno di quantificare la distribuzione dei ceppi presenti nel surnatante della superinfezione, sono ancora in corso di analisi. [less ▲]

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See detailApplication of hyperspectral Raman imaging to the analysis of a self-emulsifying drug delivery system (SEDDS).
Sacre, Pierre-Yves ULg; De Bleye, Charlotte ULg; Netchacovitch, Lauranne ULg et al

Poster (2014, June)

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of ... [more ▼]

Self-emulsifying drug delivery systems (SEDDS) are mixtures of drug and excipients that undergo emulsification when exposed to water. This pharmaceutical form is used to enhance the oral absorption of poorly water-soluble drugs. The API is finely dispersed in the excipients and forms a solid solution increasing its dissolution rate. Hyperspectral Raman imaging is a powerful tool that combines both spectral and spatial information. It returns qualitative and quantitative information useful during the development or the characterization of pharmaceutical preparations. The studied formulation consisted of a BCS 2 API (high permeability, low solubility) dispersed in excipients mainly composed of Lauroyl macrogol-32 glycerides (>50%). Two different preparations were analyzed: 100% of API dissolved and 70% of API dissolved with 30% of API powder added to the formulation. The two formulations have therefore exactly the same qualitative and quantitative composition but different spatial distribution and dispersion of the API mimicking a problem during the process. First a confocal Raman microscopic analysis was performed to evaluate the solid state of the API in the formulations. Then, an evaluation of the particle size was performed. These results are important since they can affect the bioavailability of the API and therefore its activity. Beside the microscopic scale analysis, a macroscopic imaging quantitative PLS model has been developed. The method has been validated within +/- 10% acceptance limits following the total error approach. This validated quantitative model enables reliable quantitative analysis at the pixel level of Raman images providing meaningful chemical images. [less ▲]

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See detailInhibitors of glycosylhydrolases as potential insecticides : focus on aphid model
Bosquée, Emilie ULg; Vandermoten, Sophie; Richel, Aurore ULg et al

Poster (2014, June)

Beside conventional neurotoxic compounds, new kinds of insecticides are investigated and new specific targets are in current research. According to the energy metabolic pathway, several enzymes are ... [more ▼]

Beside conventional neurotoxic compounds, new kinds of insecticides are investigated and new specific targets are in current research. According to the energy metabolic pathway, several enzymes are interesting to bring potential specific control of arthropods. Indeed, glycosylhydrolase group is very diversified from glucanases to trehalases, until chitinases. Different kinds of inhibitors were here tested to determine their potential role as new targetted aphicides. After different assays using the selected inhibitors in artificial diets, the most efficient molecules at 50-100 μg ml-1were kept for further proteomic tasks. The proteome patterns of aphids related to different inhibitor treatments were determined by two dimension electrophoresis, 2D-Differencial In Gel Expression (2D-Dige) coupled with mass spectrometry (ESI-MS-MS and Maldi-Tof-MS-MS) and data bank investigations. Particular proteins of interest were selected and accurately characterised with both fundamental but also applied views. Not only the carbohydrate metabolic pathway was disturbed with the use of glycosylhydolases inhibitors, other primary functions were also modified (amino acid synthesis, stress response, etc). This proteomic approach was discussed as an interesting and reliable tool to study the biologically involved proteins from aphids in response to specific tested enzymatic inhibitors with further ideas to be promoted as new insecticides to control insect pests. [less ▲]

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See detailExecutive function and grey matter atrophy in healthy aging: A voxel-based morphometry analysis
Manard, Marine ULg; Bahri, Mohamed Ali ULg; Salmon, Eric ULg et al

Poster (2014, June)

Introduction Executive functioning is one of the cognitive domain that declines in healthy aging (Salthouse, Atkinson, & Berish, 2003). In addition, neuroimaging studies pointed out diverse ... [more ▼]

Introduction Executive functioning is one of the cognitive domain that declines in healthy aging (Salthouse, Atkinson, & Berish, 2003). In addition, neuroimaging studies pointed out diverse neurobiological modifications associated to normal aging, such as reduced grey and white matter volumes and cortical thickness (Raz & Rodrigue; 2006). In that context, Voxel Based Morphometry (VBM; Ashburner & Friston, 2000) and Partial Least Square (PLS; McIntoch at al., 1996, 2004) were used to investigate the effect of grey matter atrophy on executive abilities in normal aging. Methods Thirty six young (age range: 18-30) and 43 healthy older (age range: 60-78) adults were included in this study. Executive functioning was assessed by inhibition, updating and shifting tasks (Miyake et al., 2000), and a composite score for general executive ability was created. Structural high resolution T1-weighted images were acquired with a 3T head-only scanner using a standard transmit-receive quadrature head coil (Siemens, Allegra, Erlangen, Germany). The structural images were segmented using VBM8 toolbox, normalized to the MNI stereotaxic space and the resulting grey matter volume images were smoothed (Gaussian kernel: FWHM 8mm). PLS analyses were performed to determine regional grey matter volume differences between young and older adults, and next to identify the regional grey matter volumes specifically associated to executive performance in older participants (p<0.001). PLS is a validated multivariate approach that robustly identifies whole brain activity patterns correlated with behavioral data or experimental design (i.e., scores, conditions or tasks). Results Behavioral data showed a significant age-related decline in executive functioning (t=-5.43; p<.001). MRI analyses showed that significant age-related grey matter volume decrease was mostly observed across a large network including frontal, parietal, and temporal regions. Moreover significant positive correlations between the executive score and the grey matter volumes in older participants were found in a subset of these cortical areas: the inferior, middle and superior frontal cortex, the pre and postcentral gyri, the anterior and middle cingulate cortex, the inferior and superior parietal regions, the retrosplenial cortex, and finally, the inferior, middle and superior temporal regions. Discussion This study first replicated that executive abilities decline with age (Salthouse et al., 2003). This age-related executive decline is related to specific cerebral regions within a large fronto-temporo-parietal network sensitive to age. Interestingly, the areas whose atrophy is linked to executive abilities are quite similar to those evidenced in functional neuroimaging studies in young participants (see Collette & Van der Linden, 2002; Collette, Hogge, Salmon, & Van der Linden, 2006 for reviews). Therefore, using PLS multivariate analyses, we demonstrated that executive changes in normal aging are not dependent on atrophy in frontal areas only but rather comes from a grey matter volume decrease in a large antero-posterior brain network. [less ▲]

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See detailThe Impact of Dual-Tasking on Verbal Short-Term Memory in Children with Specific Language Impairment
Leclercq, Anne-Lise ULg; Maillart, Christelle ULg; Lange, Manon et al

Poster (2014, June)

Limitations in general processing capacities have been proposed to account for poor verbal short-term memory (STM) performances in children with SLI. Previous studies observed that STM performances ... [more ▼]

Limitations in general processing capacities have been proposed to account for poor verbal short-term memory (STM) performances in children with SLI. Previous studies observed that STM performances decreased to a larger extent in children with SLI as compared to their unaffected peers when the processing demands of the task increased (e.g., Ellis Weismer, et al., 2005; Montgomery, 2000a,b). However, in these studies, the increase in attention processing demands went with an increase in linguistic processing demands. Since children with SLI experience language processing problems, it is not clear whether general attention problems or language processing problems are at the root of their larger performance decrease as compared to their unaffected peers. This study aims at directly assessing the hypothesis that limitations in general attentional capacity are at the root of poor STM performances in children with SLI, using an attention demanding visual search task administered concurrently with nonword repetition task. Twenty-three children with SLI, 23 age-matched children, and 23 nonword span-matched children performed immediate serial recall tasks of nonwords. The STM lists were presented either alone or concurrently with the target detection task. Moreover, the target detection task either stopped or continued when children had to recall the nonwords. Results show a main effect of dual task condition on both nonword repetition accuracy and target detection accuracy. Performances in children with SLI were not more affected than in controls by the necessity to perform a concurrent visual attention task during nonword lists presentation. However, nonword recall seemed to be more challenging for children with SLI than for age-matched controls. Indeed, performances in the visual task were lower in children with SLI than in their age-matched controls, but not as compared to nonword span-matched controls. [less ▲]

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See detailStereoselective synthesis of peptidoglycan fragments on solid support
Simon, Justine ULg; Lamborelle, Nicolas ULg; Joris, Bernard ULg et al

Poster (2014, June)

The mammalian proteins, Nod1 and Nod2, are able to recognize peptidoglycan motifs during bacterial infection. Interestingly, Nod1 is a detector of peptides and muropeptides containing the meso-2,6 ... [more ▼]

The mammalian proteins, Nod1 and Nod2, are able to recognize peptidoglycan motifs during bacterial infection. Interestingly, Nod1 is a detector of peptides and muropeptides containing the meso-2,6-diaminopimelic acid (m-A2pm), a non-proteinogenic amino acid found in Gram- bacteria. In this work, we describe a synthesis of peptidoglycan motifs entirely on solid support. Solid-Phase Peptide Synthesis (SPPS), Cross Metathesis (CM) and sugar chemistry are three methods to anchor respectively amino acids, m-A2pm and sugars derivatives on a resin as solid support. [less ▲]

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See detailEffect of plant defence elicitor on aphid and disease cross infestations
Bosquée, Emilie ULg; Oumarou, Saadatou; Qiu, Dewen et al

Poster (2014, June)

Various bio-aggressors can infest potato plants (Solanum tuberosum L.) throughout its life cycle. In addition to aphids, in particular Myzus persicae Sulzer which transmits Potato virus Y (PVY), plant ... [more ▼]

Various bio-aggressors can infest potato plants (Solanum tuberosum L.) throughout its life cycle. In addition to aphids, in particular Myzus persicae Sulzer which transmits Potato virus Y (PVY), plant pathogenic fungus such as Botrytis cinerea are able to cause damage. To determine the interactions between various bio-aggressors on potato plant defence mechanisms, (1) the effect of an attack by M. persicae followed by an attack by B. cinerea and vice versa, as well as (2) the effect of an elicitor on biological parameters of M. persicae and development of B. cinerea were assessed. On the other hand, (3) the effect of Botrytis cinerea and an elicitor on the efficiency of transmission of PVY by M. persicae was examined. The previous infection by B. cinerea resulted in a significant decrease in growth rate and a sharp reduction of M. persicae fertility, while the infection level of B. cinerea followed by M. persicae infestation was non-significant. Despite a reduction in growth and fertility of M. persicae during the first days of observation, the effect of elicitor on the biological parameters of M. persicae as well as on the development of B. cinerea was non-significant. Regarding the investigations on the PVY transmission by M. persicae, when the elicitor or Botrytis is previously applied on the plant, a significant reduction in the rate of transmission was observed. [less ▲]

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See detailBelowground Chemical Ecology: The Case of Wireworms
Barsics, Fanny ULg; Delory, Benjamin ULg; Delaplace, Pierre ULg et al

Poster (2014, June)

Wireworms, clock-beetles' larvae (Coleoptera, Elateridae), are below ground pests of many crops. They cause dramatic yield losses worldwide. Research on their ecology is crucial to undertake innovative ... [more ▼]

Wireworms, clock-beetles' larvae (Coleoptera, Elateridae), are below ground pests of many crops. They cause dramatic yield losses worldwide. Research on their ecology is crucial to undertake innovative management strategies. In the field of chemical ecology, multitrophic interactions occurring in the rhizosphere are gaining increasing attention from entomologists and agronomists. Our research aims at unveiling the role of volatile organic compounds (VOC) involved in wireworms' foraging behavior, putatively leading to host localization and/or host recognition. [less ▲]

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See detailETEROGENEITÀ GENETICA DI NOROVIRUS BOVINI IDENTIFICATI IN ITALIA
Di Felice, Eliabetta; Di Profio, Federica; Melegari, Irene et al

Poster (2014, June)

I norovirus (NoV) sono piccoli virus a RNA monocatenario appartenenti alla famiglia Caliciviridae. Sulla base dell’analisi di sequenza del gene ORF2 codificante per la proteina capsidica VP1, i NoV sono ... [more ▼]

I norovirus (NoV) sono piccoli virus a RNA monocatenario appartenenti alla famiglia Caliciviridae. Sulla base dell’analisi di sequenza del gene ORF2 codificante per la proteina capsidica VP1, i NoV sono attualmente classificati in sei genogruppi (G), con GI, GII e GIV responsabili di gastroenterite nell’uomo. Calicivirus enterici morfologicamente simili a NoV umani sono stati identificati per la prima volta in vitelli diarroici nel Regno Unito nel 1978 e in Germania nel 1980. Il sequenziamento nucleotidico dell’intero genoma ha permesso di classificare i NoV bovini (BoNoV) all’interno del genogruppo III in due genotipi, GIII.1 (prototipo Bo/Jena/80/DE) e GIII.2 (prototipo Bo/Newbury/76/UK). I BoNoV hanno una diffusione mondiale con una maggiore prevalenza di virus GIII.2-like. Tuttavia, studi recenti basati sull’analisi nucleotidica a livello della giunzione fra la polimerasi (RdRp) ed il capside, hanno dimostrato la circolazione di ceppi ricombinanti. Nel presente lavoro vengono riportati i risultati di un’indagine per la ricerca e tipizzazione di BoNoV condotta su quattro allevamenti bovini ubicati nelle province di Teramo e Pescara. A tal fine, 104 tamponi rettali collezionati da vitelli asintomatici sono stati sottoposti a nested RT-PCR impiegando due set di primer specifici per BoNoV in grado di amplificare un frammento di 326 bp della RdRp. L’RNA di BoNoV è stato identificato nel 10,5% (11/104) degli animali testati. L'analisi di sequenza ha evidenziato per nove sequenze un’elevata identità nucleotidica (nt) (88-96%) con i ceppi GIII.2-like, mentre per due è stata rilevata la maggiore identità (87-90% nt) con i BoNoV GIII.1-like. Per sette ceppi è stata ottenuta anche una sequenza di circa 750 bp che includeva oltre che la regione parziale della RdRp, la regione 5’ capsidica. Sulla base dell’analisi molecolare, cinque ceppi sono risultati strettamente correlati con BoNoV GIII.2-like, mentre solo uno dei due ceppi con polimerasi GIII.1-like, ha mostrato la maggiore identità nucleotidica nei confronti di BoNoV appartenenti al genotipo 1. Il ceppo 80/TE/IT che possedeva una polimerasi GIII.1-like, a livello capsidico ha mostrato la più alta identità con ceppi GIII.2-like, suggerendo un fenomeno di ricombinazione a livello della giunzione ORF1/ORF2. [less ▲]

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See detailResearch of phosphate accumulating microorganisms from WWTPs for the recovery of phosphorus from organic wastes (3BV.3.47)
Tarayre, Cédric ULg; Michels, Evi; Buysse, Jeroen et al

Poster (2014, June)

Many wastes containing reusable components, such as nitrogen, phosphorus and potassium, are not exploited through ideal processes. As an example, in Wallonia (Belgium), the main treatment applied to ... [more ▼]

Many wastes containing reusable components, such as nitrogen, phosphorus and potassium, are not exploited through ideal processes. As an example, in Wallonia (Belgium), the main treatment applied to sewage sludge consists in incinerating the material. Such a process is chosen when the heavy metals are too concentrated in the sludge, preventing an agricultural use. However, sewage sludge, as well as manure, slurry and digestate, contain notable amounts of nutrients (nitrogen, phosphorus and potassium). Some Waste Water Treatment Plants (WWTPs) are actually designed in order to promote Phosphate Accumulating Organisms (PAOs), able to store or release phosphorus in accordance with the environmental conditions. The aim of this work is to isolate PAOs from WWTPs and evaluate their applicability to phosphorus recovery from organic wastes. Metagenomics and metabolic properties are also considered. This work is supported by the BioRefine Project, a European project in which various member states focus on recovery of inorganics from organic wastestreams. [less ▲]

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See detailRole of estradiol in the feminization of lordosis behavior in female mice
Trouillet, Anne-Charlotte ULg

Poster (2014, June)

The classic theory of mammalian brain and behavioral sexual differentiation holds that an organizational action of testosterone, secreted perinatally by the male’s testes, controls male-typical aspects of ... [more ▼]

The classic theory of mammalian brain and behavioral sexual differentiation holds that an organizational action of testosterone, secreted perinatally by the male’s testes, controls male-typical aspects of brain and behavioral development, whereas no active perinatal sex hormone signaling is required for female-typical differentiation. However, it has recently been shown using aromatase knock out (ArKO) mice, which are deprived of estradiol due to a targeted mutation in the aromatase gene, that estradiol may also actively contribute to the differentiation of female-typical aspects of behavior over a specific pre-pubertal period. Female ArKO mice showed significantly lower levels of lordosis behavior than wild type controls following adult ovariectomy and treatment with ovarian hormones. This deficit was restored by treating female ArKO mice with estradiol benzoate between postnatal days 15 and 25. However, the mechanism by which estradiol acts prepubertally in female mice to feminize lordosis behavior remains to be elucidated. Therefore, in a first attempt, we are determining which neuropeptides are in particularly sensitive to estradiol action over the prepubertal period. We will focus on neuropeptides which have been shown to be implicated in lordosis behavior. Studies by the group of Micevych have proposed an important role for NPY and beta-endorphin (B-END) neurons in the arcuate nucleus (ARC) in the estradiol-mediated activation of lordosis behavior in female rats. An in vitro study recently showed that kisspeptin directly activates ARC B-END neurons. This is particularly interesting since unpublished results from our laboratory showed that Kp neurons are directly involved in the expression of lordosis behavior. We are thus currently determining the expression of NPY, B-END, and kisspeptin in the ARC as well as μ-opioid receptors MORs in the MPN over the prepubertal period and their possible modulation by prepubertal estradiol treatment. [less ▲]

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See detailExtension patterns in pituitary macroadenomas and relation to T2-weightd signal on diagnostic MRI examinations
Potorac, I; Cattin, F; KREUTZ, Julie ULg et al

Poster (2014, June)

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See detailMembrane interactions of cyclic lipodepsipeptides from the viscosin group
Geudens, Niels; Feher, Krisztina; De Vleeschouwer et al

Poster (2014, June)

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See detailThe X-ray emission of the massive stars population in Cyg OB2
Rauw, Grégor ULg; Nazé, Yaël ULg; Wright, Nick et al

Poster (2014, June)

Cygnus OB2 contains a wealth of massive stars of spectral types O, B and Wolf-Rayet. In the framework of a Chandra legacy program to study the X-ray emission from this important association, we have ... [more ▼]

Cygnus OB2 contains a wealth of massive stars of spectral types O, B and Wolf-Rayet. In the framework of a Chandra legacy program to study the X-ray emission from this important association, we have studied the X-ray properties of its massive stars population. We show that the O-stars in Cyg OB2 follow a well-defined scaling relation between their X-ray and bolometric luminosities: log(Lx/Lbol) = −7.2 ± 0.2. Except for the brightest O-star binaries, there is no general X-ray overluminosity due to colliding winds in O-star binaries. Roughly half of the known B-stars in the surveyed field are detected, but they fail to display a clear relationship between Lx and Lbol. Out of the three WR stars in Cyg OB2, probably only WR144 is itself responsible for the observed level of X-ray emission, at a very low log(Lx/Lbol) = −8.8±0.2. The X-ray emission of the other two WR-stars (WR145 and 146) is most probably due to their O-type companion along with a moderate contribution from a wind-wind interaction zone. [less ▲]

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See detailCan we interpret linear kernel machine learning models using anatomically labelled regions?
Schrouff, Jessica ULg; Monteiro, Joao; Joao Rosa, Maria et al

Poster (2014, June)

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See detailEffect of task demands on phonological acquisition : the acquisition of phonemes in French speaking children aged 30 to 53 months in four different contexts.
Maillart, Christelle ULg; Vaucel, Cécile; Macleod, Andrea

Poster (2014, June)

When children first begin to produce the phonemes of their language, their productions are characterized by a high degree of variability (e.g., Ferguson & Farwell, 1975) and are influenced by task demands ... [more ▼]

When children first begin to produce the phonemes of their language, their productions are characterized by a high degree of variability (e.g., Ferguson & Farwell, 1975) and are influenced by task demands (Khami, Catts, & Davis, 1984). As children’s phonological representations become more defined, their productions become more stable and less influenced by the task demands. Despite the clinical significance of phonological variability, there exists no normative data that can be used to objectively describe this variability in French. The goal of the present study was to describe variability and consistency among French-speaking children between the ages of 30 and 53 months, according to task demands. A total of 153 children participated in the present study and were equally distributed in four groups (aged 30-35, 36-41, 42-47, and 48-53 months). We created a picture identification task with 65 target words, which contained the consonants of French in word initial, medial and final position. The children were asked to produce these words in four different contexts : 1) picture naming ; 2) word repetition ; 3) sentence repetition ; 4) spontaneous language. Two measures of consistency were used. (1) A consonant level analysis that investigated the stability of phonological accuracy. (2) A word level analysis that investigated the consistency of productions across the four tasks. We predict that younger children will be more influenced by changes in task complexity than older children. [less ▲]

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See detailToward a Characterization of Western Operatic Singing Voices
Larrouy, Pauline ULg; Magis, David ULg; Nowak, Marion et al

Poster (2014, May 29)

Objective: One can easily recognize the musical style of a singer by listening to his/her sung performance. Several acoustical parameters of the Western operatic singing technique have been studied ... [more ▼]

Objective: One can easily recognize the musical style of a singer by listening to his/her sung performance. Several acoustical parameters of the Western operatic singing technique have been studied. However, the number of parameters could be extended and the effect of melody on these parameters remains unclear. By observing the effects of melody and technique on acoustical and musical parameters of the singing voice, this study aims at further characterizing the Western operatic singing technique. Methods: Fifty professional singers performed two contrasting melodies (popular song and romantic melody) with two vocal techniques (with and without operatic singing technique). The common quality parameters (energy distribution, vibrato rate and extent), perturbation parameters (standard deviation of the fundamental frequency, signal-to-noise ratio, jitter and shimmer) and musical features (fundamental frequency of the starting note, average tempo, and sound pressure level) of the 200 sung performances were analyzed. Results: The results show that the choice of melody had a limited impact on the acoustical and musical parameters observed, whereas a particular vocal profile appeared depending on the vocal technique employed. By examining these parameters in a theoretical model, this study highlights the relevance of vibrato rate, sound level, energy distribution, fundamental frequency of the starting note and tempo in describing the Western operatic singing technique. Conclusions: This study confirms that vocal technique affects most of the parameters examined and that the effect of melody is limited. In addition, the observation of quality and musical parameters contributes to a better understanding of the operatic singing technique. Conversely, the perturbation parameters don’t seem to take part in the characterization of operatic singing voices. Although the suggested theoretical model needs to be further developed in future research, it already generates implications for research and teaching. [less ▲]

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See detailJuvenile sexual offenders: Can their language tell us how their mind works?
Courtain, Audrey; Glowacz, Fabienne ULg

Poster (2014, May 27)

A significant proportion of sexual delinquency being committed by juveniles, various fields of research have studied this topic. Still, little is known about the relation between the linguistic ability ... [more ▼]

A significant proportion of sexual delinquency being committed by juveniles, various fields of research have studied this topic. Still, little is known about the relation between the linguistic ability and the cognitive functioning of this specific youth. Rooted in scientific works which have explored indirectly the point, this poster attempt to question the quality of language as a mean to find out how their mentalization occurs, but also to question how their cognitive processes (e.g. empathy) influence their language. These hypothesis are to be tested soon with a clinical sample of 47 participants and with different measures (e.a. MACI, verbal IQ, IRI). Hence, the opportunity to evaluate, among others, empathy deficits and cognitive distortions through language can be considered a promising approach allowing new perspectives for prevention, assessment and treatment of juvenile sexual offenders. [less ▲]

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See detailMaintaining people with multiple sclerosis at work: Validation of a questionnaire identifying their professional difficulties
Blavier, Adelaïde ULg; Monisse, Aurélie; Berkail, Radia et al

Poster (2014, May 27)

The purpose of this paper is to present the construction and validation of a questionnaire in order to evaluate the specific work difficulties and compensation mechanisms developed by multiple sclerosis ... [more ▼]

The purpose of this paper is to present the construction and validation of a questionnaire in order to evaluate the specific work difficulties and compensation mechanisms developed by multiple sclerosis patients (MS). At the moment, only few very recent questionnaires (in English) are constructed in order to highlight the link between the patients’ cognitive deficits with their professional situation (Doogan & Playford, 2014; Honan et al., 2012; McFadden et al., 2012). This lack of accurate assessment is detrimental to the patients’ job retention. Our questionnaire was constructed from review of literature and interviews of patients and experts. In order to validate our questionnaire and to test its specificity to MS patients, three groups of participants answered the questionnaire: MS patients, diabetic patients (diabetes is also a chronic illness but without any cognitive deficits contrary to MS) and a control group. We controlled the effect of anxiety and depression and we conducted a factorial analysis that showed the existence of 3 factors: the ergonomic factor (that includes cognitive difficulties and resources and adaptation process), the description of work situation and the social support. The three groups of participants obtained similar results for the work description and the social support while the group of patients with MS obtained a higher score than the other 2 groups for the ergonomic factor. These results suggest that our questionnaire is specific to the MS population and to the difficulties they specifically meet in their work situations. These results highlight new research opportunities and specific ways to increase job retention in MS population. [less ▲]

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See detailDetection of eye movements specific to drowsiness and their relation with subjective assessment: A cognitive ergonomic approach.
Blavier, Adelaïde ULg; Montagnino, Cédric; Wertz, Jérôme ULg et al

Poster (2014, May 27)

Drowsiness is one of the major factors explaining accidents, particularly in traffic accidents but also in work situations with serious consequences (e.g. medicine). The drowsiness may be assessed by ... [more ▼]

Drowsiness is one of the major factors explaining accidents, particularly in traffic accidents but also in work situations with serious consequences (e.g. medicine). The drowsiness may be assessed by diverse measures that vary from physiological and unconscious data (e.g. EEG) to subjective and conscious evaluation. In their daily life, people are used to evaluate their drowsiness by subjective assessment and research observes a great inter-individual variation in this evaluation. Moreover, the subjective evaluation is dependent on the situation and the risk perceived by the person (e.g., new versus usual situations, simple versus complex environments, etc.). In this theoretical context, our purpose was to investigate the links between 1) objective performance (reaction time) measured by a psychomotor vigilance task (PVT), 2) data from eye movements and 3) subjective assessment of drowsiness (measured with Karolinska Sleepiness Scale, KSS). 12 persons, aged from 20 to 56, participated individually. They were asked to respect a 60% sleep deprivation during the night before the experiment and to not drink any energy drinks the day of the experiment. The experiment was conducted between 1 and 3 PM after a heavy lunch in order to increase the circadian effect. Moreover, the temperature of the room was 25° in order to increase drowsiness. Each participant was asked to perform 4 PVT. However, although 100% of participants performed the first two PVT, only 66% were able to perform the third PVT and only 33% of participants performed the fourth and last PVT. Our results showed an effect of time on objective performance, eye movements and subjective assessment of drowsiness in PVT 1 and 2: significant increase of reaction time, increase of eye closure and perclos, reduction of pupil diameter and increase of subjective drowsiness estimation (KSS). Only the frequency and duration of blinks remained constant across time. In PVT 3 and 4, data from eye movements and objective performance (reaction time) did not vary anymore across the time. Only the subjective estimation of drowsiness (KSS) continued to increase. Furthermore, subjective estimation of drowsiness was differently correlated with eye movements and objective performance across the PVT; it was significantly correlated with reaction time (PVT 1,2,3), blink frequency and duration (PVT 1,2,3), perclos (PVT 1,2,3,4), eye closure (PVT 2,3), pupil diameter (PVT 1,2,3,4). These results are discussed and integrated in an ergonomic approach in order to analyze the links between objective performance, eye movements and subjective assessment of drowsiness. [less ▲]

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See detailSynthesis of a glucosamine labeled amphiphilic polymer for drug delivery application
Riva, Raphaël ULg; Boyère, Cédric; Debuigne, Antoine ULg et al

Poster (2014, May 27)

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See detailEmpathy and social relationships in suicidal adolescents
Jadin, Aurore ULg; Vermaelen, Noémie; Blavier, Adelaïde ULg

Poster (2014, May 27)

Empathy and suicide among minor people are two research topics currently very explored. Psychologists often speak about suicide because it represents the second cause of mortality among 15-24-year-old ... [more ▼]

Empathy and suicide among minor people are two research topics currently very explored. Psychologists often speak about suicide because it represents the second cause of mortality among 15-24-year-old adolescents (Delvenne, 2005). Several studies have already analyzed the links between empathy skills and some psychopathology (behavioral disorders, hyperactivity and alcoholism) but no research before this one has developed empathic abilities in suicidal adolescents. The aims of the present study were respectively to examine suicidal adolescents’ empathy skills, interpersonal capacities and to investigate the quality of their social relationships. [less ▲]

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See detail[18F]UCB-H AS A BRAIN SV2A RADIOTRACER: A FIRST CLINICAL TRIAL
Bahri, Mohamed Ali ULg; Bastin, Christine ULg; Aerts, Joël ULg et al

Poster (2014, May 27)

[18F]UCB-H is a fluorine-18 radiolabelled PET imaging tracer with a high affinity for the synaptic vesicle protein 2A (SV2A). This protein, involved in vesicle trafficking and widely distributed in the ... [more ▼]

[18F]UCB-H is a fluorine-18 radiolabelled PET imaging tracer with a high affinity for the synaptic vesicle protein 2A (SV2A). This protein, involved in vesicle trafficking and widely distributed in the brain, represents the binding site and the primary mechanism of the antiepileptic drug levetiracetam. Levetiracetam has recently been suggested to reduce synaptic deficits in a mouse Alzheimer’s disease model and to improve cognition in patients with amnestic mild cognitive impairment, suggesting a possible role for this protein in synaptic integrity. The objective of this study was to investigate the cerebral distribution of [18F]UCB-H in healthy human volunteers. Dynamic PET imaging of the head of four healthy volunteers was performed over 100 minutes after injection of 170.4 ± 24.9 MBq of GMP produced [18F]UCB-H. The input function was acquired by arterial blood sampling during the dynamic PET acquisition. Blood data analysis showed a consistent tracer amount in whole blood and plasma indicating a very low degree of binding of the tracer to the red blood cells. Unchanged [18F]UCB-H fraction in plasma follows a bi-exponential behavioral decrease with a starting fraction of 92% of the injected amount of the tracer, measured at 3 min post injection. This fraction decreases to about 50% at 10 min post injection. The [18F]UCB-H PET data revealed a high and rapid uptake in the grey matter structures, matching the known ubiquitous distribution of SV2A in the brain. The kinetics of the tracer in the brain was characterized by an initial high uptake phase followed by rapid washout allowing the standard compartmental modeling (1-tissue compartment, 2-tissue compartment, and Logan graphical analysis). The three models gave consistent results. The two-tissue compartment model fitted the experimental data best and provided a total distribution volume of [18F]UCB-H in the brain greater than 7 mL/cm3 and a specific distribution volume around 3 mL/cm3. Our results indicate that [18F]UCB-H is a new radiotracer for brain SV2A proteins suitable for human studies. Further studies are warranted to assess SV2A modifications in neurological pathologies such as Alzheimer’s disease. [less ▲]

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See detailInfluence of melodic context on the perception of vocal pitch accuracy
Beeken, Manon; Morsomme, Dominique ULg; Larrouy, Pauline ULg

Poster (2014, May 27)

In order to categorize sung performances as “in tune” or “out of tune”, one can measure the deviation between the performance and the musical notation. Depending on the study, a deviation of a semitone ... [more ▼]

In order to categorize sung performances as “in tune” or “out of tune”, one can measure the deviation between the performance and the musical notation. Depending on the study, a deviation of a semitone (100 cents) or a quartertone (50 cents) is considered as “out of tune”. However, these values are arbitrary and the current study aims to define perceptual thresholds of pitch accuracy in a melodic context. For this purpose, melodic sequences were manipulated, from “in tune” (deviation of 0 cent) to “out of tune” (10 to 80 cents, in 10 cents steps). In a 2x2x2 design we systematically varied the conditions of: melodies (ascending/descending target-interval), type of errors (interval or tonality deviation), and direction of the deviation (enlargement or compression). The sequences were presented to 30 non-musicians using the method of limits procedure, in a test/retest paradigm. For each condition, they were asked to specify whether the presented singing performances were “in tune” or “out of tune”. The results showed that participants were consistent in their evaluation between the test and the retest. The pitch accuracy threshold (M = 29 cents, ES = .75) was not influenced by the melody, the type of errors, and the direction of the deviation. This study highlights the ability of non-musicians to perceive small pitch deviations (less than a quartertone) in a melodic context. This finding elucidates on the concept of pitch accuracy and therefore yields the opportunity to revise objective tools for the evaluation of singer pitch accuracy. [less ▲]

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See detailLong protocols to Rorschach Comprehensive System and a posteriori reduction of number of responses: What is the impact on the clinical interpretation ?
Dufour, Cristelle; Englebert, Jérôme ULg; Blavier, Adelaïde ULg

Poster (2014, May 27)

Our study was interested in the exceptionally long protocols, superior to 55 answers, supplied by five subjects in the test of Rorschach according to the method of the Comprehensive System. In order to ... [more ▼]

Our study was interested in the exceptionally long protocols, superior to 55 answers, supplied by five subjects in the test of Rorschach according to the method of the Comprehensive System. In order to gain understanding of which attitude to adopt in front of this kind of protocol, we made a a posteriori reduction of the number of answers by basing us on the recommendations of Exner (Exner, on 2001), then a comparative study between the clinical interpretation realized with all of the answers and with only the first five answers by board. We also replicate this methodology of a posteriori decrease of the number of answers with four answers by board according to the new recommendations of the system R-PAS of Meyer and al. (Meyer and al, on 2009). The sample consists of three raw coal subjects and two psychiatric subjects. Our analysis highlighted a stability of certain variables (EB, Lambda, EA for example) but a difference in the psychological profile of the subjects after reduction. We observed a clarification of the fundamental difficulties to the psychiatric subjects and rather a neutralization of these difficulties for the raw coal subjects, with particularly defence mechanisms which seem more adapted. In our sample, the consideration of all of the answers or only of the partial protocol thus brings a difference in the clinical interpretation ; as a consequence any reduction should be made with big caution. Our study allows to discuss current practices of the test of Rorschach, by looking for a compromise between the inherent constraints to the validity of the test and the questions of the clinical complexity decrease appropriate to any initiative of standardization. [less ▲]

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See detailCorrelation and integration of the Rorschach Comprehensive System and the TCI-R questionnaire
Rentmeister, Daniel; Blavier, Adelaïde ULg; Di Piazza, Laetitia ULg et al

Poster (2014, May 27)

In this study, a dual purpose is sought. First, we statistically compare the Rorschach test interpreted by the Comprehensive System from J.E. Exner and the Temperament and Character Inventory – Revised by ... [more ▼]

In this study, a dual purpose is sought. First, we statistically compare the Rorschach test interpreted by the Comprehensive System from J.E. Exner and the Temperament and Character Inventory – Revised by R. Cloninger to highlight their differences and similarities. Second, through clinical cases, we discuss the relevance of integrating the results obtained by these two tools to establish a comprehensive and consistent psychological profile of an individual. For the statistical comparison, a sample of 27 “healthy” subjects (M = 24.37 years, SD = 2.75) was first submitted to the Rorschach test. Then, immediately after, each subject completed the TCI-R. A correlation analysis (Pearson Rho) was done between various Index and a Bonferroni adjustment was made. For the case studies, 3 subjects were recruited. Anamneses were carried out and the Rorschach test and TCI-R administered. Our first results, which are to be taken with caution because of the small number of subjects in the sample, must be qualified and discussed. From 2448 statistical comparisons, we select the most relevant and discuss different correlation results. The case studies show a concordance in social relationships and impulsivity; and show that the information peculiar to each test allows us to complete the subject’s profile. Finally, it is by addressing two different epistemologies underlying these two tests that we can best explain the psychological differences highlighted in the same individuals. We conclude by suggesting that this difference in results must certainly be understood in an integrative logic and emphasizes the complementarity between these two tests. [less ▲]

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See detailMultilayered chitosan-based fibers for skin regenaration applications
Croisier, Florence ULg; Detrembleur, Christophe ULg; Jérôme, Christine ULg

Poster (2014, May 26)

Chitosan is a natural polymer derived from the chitin of crustacean or mushroom shells, that intrinsically presents haemostatic, mucoadhesive, antimicrobial and immunostimulant properties. This ... [more ▼]

Chitosan is a natural polymer derived from the chitin of crustacean or mushroom shells, that intrinsically presents haemostatic, mucoadhesive, antimicrobial and immunostimulant properties. This polysaccharide has shown a great potential for biomedical and pharmaceutical applications, on account of its remarkable compatibility with physiological medium. Besides, it is degraded in a physiological environment into non-toxic products, which make chitosan an outstanding candidate for short- to medium-term applications. In this respect, nanometric fibers are highly interesting as their assembly mimics the skin extracellular matrix structure. Such nanofibrous materials can be prepared by electrospinning (ESP). This technique uses a high voltage to create an electrically charged jet of polymer solution or melt which leads to fibers formation. Depending on the polymer characteristics (a.o. molecular weight, solution viscosity and conductivity) and processing conditions (electric potential, distance between syringe-capillary and collection plate, concentration, flow rate), polymer fibers ranging from nanometers to a few microns in diameter can be obtained and subsequently used as potential scaffolds, a.o. to form a temporary, artificial extracellular matrix. In the present study, electrospinning technique was combined with layer-by-layer deposition method (LBL) - a well-known method for surface coating, based on electrostatic interactions - in order to prepare multilayered chitosan-based nanofibers. The antibacterial properties of the obtained material were then assessed, and the presence of a multilayered deposit was confirmed by several techniques. The multilayered chitosan-based nanofibers produced present great prospects for the preparation of new biomedical scaffolds - such as wound dressings that could improve skin regeneration. [less ▲]

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See detailAn innovative lens surface functionalization to control Posterior Capsular Opacification
Huang, Yi-Shiang ULg

Poster (2014, May 26)

Cataract is the opacity of the lens, causing impairment of vision or even blindness and the surgery is still the only available treatment today. The intraocular lens (IOL) is a polymer implant designed to ... [more ▼]

Cataract is the opacity of the lens, causing impairment of vision or even blindness and the surgery is still the only available treatment today. The intraocular lens (IOL) is a polymer implant designed to replace the natural lens in the cataract surgery. However, the bio-inert materials could not satisfy the unmet need in the secondary cataract control. Posterior capsular opacification (PCO, or Secondary Cataract), characterized by a thick and cloudy layer of lens epithelial cells (LECs), is the most common postoperative complication. For the present study, a bioactive molecule is immobilized onto the conventional acrylic hydrophilic polymer pHEMA (Poly(2-hydroxyethyl methacrylate)) using oxygen plasma treatment followed by dip-coating deposition. The RGD peptide sequence, being well-known for its ability to promote cellular attachment by binding to integrin receptors, is designed to stimulate the adhesion of LECs on the IOL. The data have shown the peptide immobilized biomaterial not only exhibits similar optical and physical properties, but also reveals enhanced bio-logical properties in cell adhesion and cell morphology maintenance. By means of surface functionalization of IOL to stimulate LECs adhesion, the secondary cataract could be controlled. [less ▲]

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See detailTrappist Beers: Exploring the Cloak of Secrecy by GC×GC-TOFMS
Allen, C; Loughnane, C; Stefanuto, Pierre-Hugues ULg et al

Poster (2014, May 21)

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See detailA multi-step process for an alternative wheat bran biorefinery
Aguedo, Mario ULg; Fougnies, Christian; Richel, Aurore ULg

Poster (2014, May 21)

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See detailMeasurement of Trace levle Dechlorane Flame Retardants in Food and Feed by GC-MS/MS
L'Homme, Benjamin ULg; Calaprice, C; Brasseur, Catherine ULg et al

Poster (2014, May 21)

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See detailBioactive Intraocular Lens - A Strategy to Control Secondary Cataract
Huang, Yi-Shiang ULg

Poster (2014, May 21)

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See detailEffects of wheat/oilseed rape and wheat/pea associations on the diversity of aphids and aphidophagous beneficials
Chevalier Mendes Lopes, Thomas ULg; Bosquée, Emilie ULg; Honba, David et al

Poster (2014, May 20)

This study was conducted in the Shandong province (China) to better characterize the effect of wheat/oilseed rape and wheat/pea associations on the populations of aphids and aphidophagous beneficials. At ... [more ▼]

This study was conducted in the Shandong province (China) to better characterize the effect of wheat/oilseed rape and wheat/pea associations on the populations of aphids and aphidophagous beneficials. At specific times of the season, the observations on wheat tillers confirm the resource concentration and the enemy hypotheses. In fact, aphids were more abundant in the pure stand of wheat, while more ladybirds were observed in the associations. As for the trapping of aphidophagous beneficials, the parasitoid species Aphidius gifuensis (Ashmead) was prevalent. Among predators, Propylea japonica (Thunberg) and Harmonia axyridis (Pallas) were the most abundant species. Few lacewings and hoverflies were trapped. This study shows a beneficial effect of crop associations on the control of aphid populations. [less ▲]

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See detailA methodology for elicitor screening of winter wheat infected by STB and FHB
Le Mire, Géraldine ULg; SIAH, Ali; Deleu, Magali ULg et al

Poster (2014, May 20)

Un doctorat au sein de Gembloux Agro Bio-Tech (Plateforme Agriculture Is Life) vise à développer une méthode à base d'éliciteurs bio-sourcés pour protéger le blé d'hivers contre la Septoriose (STB) et la ... [more ▼]

Un doctorat au sein de Gembloux Agro Bio-Tech (Plateforme Agriculture Is Life) vise à développer une méthode à base d'éliciteurs bio-sourcés pour protéger le blé d'hivers contre la Septoriose (STB) et la Fusariose (FHB). Dans ce cadre, la mise au point d'un protocole efficace d'infection du blé est élémentaire avant de pouvoir entamer les tests de screening d'éliciteurs. Nous présentons ici une méthode d'infection du blé par Septoria tritici et les résultats de ces tests de reproduction de symptômes. [less ▲]

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See detailFrom nets to bottom traps: is exploitation of Norway lobsters a suitable option for Corsican common spiny lobster fishermen?
Patrissi, Michela; Astrou, Adèle; Pelaprat, Corinne et al

Poster (2014, May 20)

In Corsica (NW Mediterranean), most of the fishing activity is composed of small-scale artisanal fisheries, and takes place on the western coast. The common spiny lobster (Palinurus elephas) is the main ... [more ▼]

In Corsica (NW Mediterranean), most of the fishing activity is composed of small-scale artisanal fisheries, and takes place on the western coast. The common spiny lobster (Palinurus elephas) is the main target of Corsican netters. However, its populations have been declining since the 1950's, questioning the sustainability of this activity. We therefore tried to assess whether the fishing effort, currently mostly focused on common spiny lobsters, could be moved towards other commercially-interesting deep crustaceans, such as the Norway lobster (Nephrops norvegicus), through diversification of artisanal fishing practices. With the help of local fishermen, we set up Scottish traps for Norway lobsters at depths of 300 to 400 meters, on sandy and muddy bottoms of both eastern and western coasts. Despite several tests using different baits and soak times at various depths or seasons, catches on the western coast were low. On the other hand, on the eastern coast, experimentation showed interesting yields, and large mean size (i.e. high commercial value) for both sexes. While more studies are needed to confirm these results and improve knowledge of Norway lobster stocks, trap fishing of this species on eastern coast of Corsica could be a suitable alternative for diversification of artisanal fisheries. [less ▲]

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See detailFive Years of aphidophagous species sampling in belgian corn
Vandereycken, Axel ULg; Fassotte, Bérénice ULg; Durieux, Delphine ULg et al

Poster (2014, May 20)

The community of aphidophagous species present in agroecosystems is disturbed since the introduction of an exotic species the Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera ... [more ▼]

The community of aphidophagous species present in agroecosystems is disturbed since the introduction of an exotic species the Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae). In this intensive agricultural area, five aphids predator species are commonly observed: three coccinellids H. axyridis, Coccinella septempunctata, Propylea quatuordecimpunctata, one hoverfly Episyrphus balteatus, and one lacewing Chrysoperla carnea. This study focuses on the occurrence of the five most abundant aphid predators and their seasonal abundance in corn. The abundance of adults and larvae of these species was evaluated over a five-year period, from 2009 to 2013. The sampling method consisted in the counting of aphids and all developmental stages of aphidophages present in quadrats of 1m² from April to November. Densities of aphid predators changed during five years studies. Since 2011, H. axyridis was the most abundant aphids predators in corn. H. axyridis numbers were found to increase over the first four inventoried year, reaching in 2012 86% for adult stage (119,7±7,8 adults/100m2) and 76% for larvae stages (242,8±14,2 larvae/100m2) of the aphid predators, while in 2009 these ratios were 14% and 23% respectively. For C. septempunctata and P. quatuordecimpunctata the population densities decrease at the end of the five years period. Population densities of C. carnea and E. balteatus were variable during the sampling period but increased in 2013. Phenology of the five studied species presents similar curves following the aphid abundance. The most abundant observed aphids were metopolophium dirhodum, rhopalosiphum padi, rhopalosiphum maidis, sitobion avenae and sitobion fragariae. H. axyridis starts reproducing after the peak in aphid population, suggesting that H. axyridis is able to complete its development by feeding on alternative prey such as larvae and pupae of conspecific and heterospecific. H. axyridis is a bivoltine species but the second generation was stop by the corn harvesting. [less ▲]

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See detailEvaluation of the aphid and aphidophagous beneficials diversity in a pea and potato association
Bosquée, Emilie ULg; Chevalier Mendes Lopes, Thomas ULg; Serteyn, Laurent et al

Poster (2014, May 20)

Crop associations can have beneficial effects on the control of insect pests. This study was conducted in the Shandong province (China) to assess the impact of potatoes and peas association on the ... [more ▼]

Crop associations can have beneficial effects on the control of insect pests. This study was conducted in the Shandong province (China) to assess the impact of potatoes and peas association on the populations of aphids and aphidophagous beneficials. Observations on potato plants and trapping were performed. During the season, the degree of infestation didn’t differ significantly between the association and the pure stand. However, the aphidophagous beneficials were more abundant in the association comparing to the pure stand. Trapping results give a more general idea about the richness and diversity of natural enemies present in the environment. Aphidius gifuensis (Ashmead) and Aphelinus abdominalis Dalman are the most abundant parasitoids. Among predators, Propylea japonica (Thunberg) and Harmonia axyridis (Pallas) are prevalent. Few hoverflies and lacewings were trapped. Results from the observations on plants do not support the resource concentration hypothesis. However, the enemy hypothesis was confirmed for the aphidophagous beneficials. Therefore, this association can have a beneficial effect on the control of aphid populations. [less ▲]

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See detailNeoadjuvant chemotherapy in breast cancer patients induces expression of tumor suppressor miR-34a
FRERES, Pierre ULg

Poster (2014, May 19)

Circulating microRNAs (miRNAs) are extensively studied in cancer as biomarkers but little is known about the influence of anti-cancer drugs on their expression. In this presentation, we describe the ... [more ▼]

Circulating microRNAs (miRNAs) are extensively studied in cancer as biomarkers but little is known about the influence of anti-cancer drugs on their expression. In this presentation, we describe the modifications of circulating miRNAs profile under neoadjuvant chemotherapy (NAC) for breast cancer. [less ▲]

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See detailJob characteristics and work engagement: multiple-group analyses of flexibility practices
Travaglianti, Fabrice ULg; De Zanet, Fabrice ULg; Vandenberghe, Christian et al

Poster (2014, May 16)

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See detailSite-specific sediment characteristics impact on metal bioavailability and bioaccumulation in the Polychaete Nereis virens
Pini, Jennifer; Richir, Jonathan ULg; Watson, Gordon

Poster (2014, May 15)

The king ragworm (Nereis virens) is a cosmopolitan species of soft sediment inter-tidal communities and is known to be impacted by various pollutants. More precisely, in many coastal locations, N. virens ... [more ▼]

The king ragworm (Nereis virens) is a cosmopolitan species of soft sediment inter-tidal communities and is known to be impacted by various pollutants. More precisely, in many coastal locations, N. virens is exposed to a range of metals including copper and zinc which are known to be highly toxic. However, the relationships between metal bioavailable concentrations in the sediment, the pore water and the tissues of N. virens have not yet been investigated in this is ecologically and commercially important species. Hence, to investigate these relationships, sediment, pore water and associated worms samples were collected from seven sites along the English Channel coast of the UK, chosen for their different pollution histories. The BCR three-step sequential extraction procedure was used to assess the bioavailable metal concentrations in the sediment, in conjunction to standard extraction techniques to determine the tissue and the pore water concentrations. All samples were measured by Atomic Absorption Spectroscopy (FAAS). Results from correlation analyses showed that site specificities and metal pollution histories along with sediment characteristics (organic content and particle size) were important factors regarding the bioavailability of copper and zinc to worms. Indeed, sediment organic content and grain size were positively correlated to metal bioavailable concentrations in the sediment. Strong correlations were found between copper bioavailability in the sediment and in the pore water and between zinc concentrations in the pore water and in N. virens. These results showed that zinc from the pore water was more readily bioavailable to N. virens than copper. However, our data suggested that N. virens accumulated metals regardless of the pollution history/level of the sites. In addition, our data showed that metal concentrations in N. virens were lower than those found in other closely related polychaetes such as N. diversicolor. This suggests that N. virens, unlike other polychaetes, is well adapted to highly contaminated sites by the possible use of specific metal regulation mechanisms, which would require further analysis. [less ▲]

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See detailCadmium and mercury sediment pollution along the British coastline of the Channel: A first spatio-temporal integrated approach
Richir, Jonathan ULg; Pini, Jennifer; Watson, Gordon

Poster (2014, May 15)

Cadmium (Cd) and Mercury (Hg) are 2 widespread trace metals occurring in both terrestrial and marine environments. They play no physiological role and are often toxic even at low concentrations and were ... [more ▼]

Cadmium (Cd) and Mercury (Hg) are 2 widespread trace metals occurring in both terrestrial and marine environments. They play no physiological role and are often toxic even at low concentrations and were therefore identified as priority hazardous substances under the European Water Framework Directive and included in the European List I of Dangerous Substances. Marine sediments are considered as the ultimate sink of non-degradable metals, where they can accumulate in considerable quantities. The UK coastline has been polluted with metals for decades or even centuries and, although many studies have monitored sediment metal loads in specific locations, there has been no recent systematic monitoring approach along the whole of the south coast. In addition, few reliable data exist on decadal temporal trends for most sediment pollutants. Focusing on Cd and Hg, we have investigated their spatial and temporal distribution in sediment samples collected from 42 sites along the English coast of the Channel from 1990 to 2010. From a temporal point of view, data analyses showed that mean Cd levels in sediments significantly decreased by 59 % during that period of time, from 0.78 to 0.32 mg kgDW-1 of sediments. This reflects a decrease globally to below the 0.70 mg kgDW-1 Cd Threshold Effect Level (TEL). Adverse effects caused by Cd on the biota should, therefore, be rare. Spatially, Cd displayed an east-to-west increase of its levels, with several western sites with Cd still above the TEL. Regarding Hg, sediment levels did not significantly change from 1990 to 2010, remaining approximately twice as high as the corresponding 0.13 mg kgDW-1 Hg TEL. Hg also displayed an east-to-west increase of its levels, whilst 55 % of monitored sites had a mean sediment Hg concentration in average 3.5 times higher than the TEL. Despite regulations, non-degradable metals such as Cd and Hg that have accumulated in sediments over considerable periods of time may consequently still pose threats to aquatic organisms, highlighting the need for continued extensive spatially and temporally integrated monitoring approaches. [less ▲]

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See detailHow to build a biological linker dedicated to the engineering of novel drug delivery systems
Crasson, Oscar ULg; Galleni, Moreno ULg; Parente, Raffaella et al

Poster (2014, May 15)

Nowadays, chemical linkages are widely used in industry to coat bioactive molecules on biocompatible supports. However, some issues inherent to the linkage procedure remain. For example, chemical ... [more ▼]

Nowadays, chemical linkages are widely used in industry to coat bioactive molecules on biocompatible supports. However, some issues inherent to the linkage procedure remain. For example, chemical reactions often damage the structure and therefore the activity of the immobilized molecules. In this work, we propose the use of a human chitin binding domain (ChBD) to immobilized bioactive molecules on a polysaccharide-based surface. ChBD belongs to the human chitinase called chitotriosidase and was shown to interact specifically with chitin and chitooligomers. Using molecular biology and protein engineering, we have developped of a new biological tool based on the hybrid protein technology. In this technology, we can create chimeric proteins that have the ability to bind polysaccharidic supports thanks to their binding domain that can be covalently linked with any bioactive molecule that can confer prophylactic or therapeutic activities. In this study, we have successfully shown that we can use the chitin binding domain (ChBD) from the human chitotriosidase as a biological linker dedicated to the engineering of novel drug delivery systems containing chitin or other analogous polysaccharides. [less ▲]

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See detailDiscrimination of two geographically distinct populations of sea bass Dicentrarchus labrax, using stable isotopic signatures of mercury (δ202Hg, Δ199Hg)
Cransveld, Alice ULg; Amouroux, David; Koutrakis, Emmanuil et al

Poster (2014, May 15)

Despite the reduction of mercury (Hg) emissions in Europe in the last decades, Hg emissions are increasing worldwide and concentrations found in some marine predators remain high. This raises questions on ... [more ▼]

Despite the reduction of mercury (Hg) emissions in Europe in the last decades, Hg emissions are increasing worldwide and concentrations found in some marine predators remain high. This raises questions on mercury's biogeochemical cycle at both local and global scale. In the present work, we investigate the possibility to use mercury isotopic signature in fish as a tool to discriminate different polluted areas and potential pollution sources. Indeed, Hg can exhibit both mass-dependent (MDF) and mass-independent fractionation (MIF). While MDF may occur during biological cycling inter alia and could be used to understand bioaccumulation processes, MIF provides a unique fingerprint of specific chemical pathways, such as photochemical transformations. In this context, information provided by Hg isotopes would help to improve environmental management strategies. A preliminary set of four and ten juvenile common sea bass, Dicentrarchus labrax were collected from the North Sea and the Aegean Sea respectively. T-Hg was analysed by direct mercury analyser (DMA), speciation by gas chromatography inductively coupled plasma mass spectrometer (GC-ICP-MS) and Hg isotope analysis were performed using cold vapour generation with multicollector ICP-MS. Total Hg concentrations in all tissues were higher in individuals from the North Sea ( Hgtot muscle=1,14 ± 0,48 mg.kg-1 dw) than from Greece (0,60 ± 0,06 mg.kg-1 dw). Speciation analysis shows that MeHg is the predominant form of Hg in muscle (89% MeHg on average) but not in liver (51% MeHg on average). Isotopic mass dependent values (δ202Hg) values were always higher in muscle than in liver and related to Hg species distribution. For mass independent isotopic signature, sea bass from the Aegean Sea had a systematically higher Δ199Hg value than individuals from the North sea (e.g.: 0,56 ± 0,05‰ and 0,32 ± 0,06‰ respectively in muscle). While mass dependent isotopic signature probably reflects some internal Hg metabolism, mass independent isotopic signature seems definitely site dependent. Such isotopic discrimination might be in agreement with difference in both mercury sources and cycling in the North and Aegean Seas. These preliminary results indicate that Hg isotopes may thus help to discriminate fish from different areas. This promising outcome must be further confirmed by extending the number of individuals and locations to be investigated. [less ▲]

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See detailÉvaluation des effets de la formation et de la supervision de services d'aide aux familles qui accompagnent des personnes atteintes d¿une maladie de type Alzheimer
Marquet, Manon ULg; Missotten, Pierre ULg; Charlot, Valentine ULg et al

Poster (2014, May 15)

Introduction : Il est nécessaire de développer des interventions visant à aider les professionnels qui accompagnent des personnes âgées (atteintes ou non de démence). Les programmes existants sont ... [more ▼]

Introduction : Il est nécessaire de développer des interventions visant à aider les professionnels qui accompagnent des personnes âgées (atteintes ou non de démence). Les programmes existants sont néanmoins essentiellement destinés aux aidants en milieu institutionnel. Objectif : Évaluer, au niveau de différents paramètres (âgisme, connaissances sur la maladie d’Alzheimer, sentiment de compétence, satisfaction professionnelle, burnout, stratégies de coping), l’efficacité d’une intervention destinée à des aidants professionnels à domicile. Méthodologie : 17 aides familiales ont bénéficié d’une formation et de supervisions visant à améliorer leurs connaissances sur les démences et à les aider à mettre en place des stratégies de résolution de problèmes face aux difficultés rencontrées dans leur pratique, et ceci, afin de favoriser une vision moins stigmatisante de la maladie d’Alzheimer. Différents auto-questionnaires ont été complétés par les participantes avant et après l’intervention. Résultats : Les analyses statistiques indiquent que l’intervention permet de diminuer l’âgisme des aidantes, d’améliorer leurs connaissances sur la maladie d’Alzheimer, leur sentiment de compétence et leur satisfaction vis-à-vis de leurs tâches professionnelles. Conclusion : L’intervention est efficace puisqu’elle atteint ses objectifs initiaux. Ces résultats encouragent non seulement la formation des aidants professionnels à domicile mais aussi l’évaluation de l’efficacité des interventions proposées, à la fois auprès des aidants professionnels, informels et des personnes accompagnées. En effet, sur base de la littérature [Avorn & Langer, 1982 ; Coudin & Alexopoulos, 2010], nous faisons l’hypothèse que l’amélioration des connaissances et la diminution de l’âgisme réduisent le risque d’induire des comportements de dépendance chez les personnes accompagnées. Ce constat est important compte tenu du rôle des aides familiales, à savoir aider les personnes âgées (atteintes ou non de démence) qui présentent des difficultés dans la réalisation des activités (instrumentales) de la vie quotidienne afin qu’elles restent le plus longtemps possible à leur domicile. [less ▲]

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See detailMaize cold tolerance : in search of relevant parameters for discriminating genotypes
Riva-Roveda, Laetitia ULg; Escale, Brigitte; Giauffret, Catherine et al

Poster (2014, May 15)

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See detailImpact des stéréotypes liés au vieillissement et à la maladie d’Alzheimer sur le vécu des aidants familiaux
Bottard, Aude; Adam, Stéphane ULg; Gilles, Christian et al

Poster (2014, May 15)

INTRODUCTION Dans notre société, les personnes âgées atteintes de la maladie d’Alzheimer sont les cibles à la fois de stéréotypes liés à l’âge, mais aussi de stéréotypes liés à cette maladie (Sartorius ... [more ▼]

INTRODUCTION Dans notre société, les personnes âgées atteintes de la maladie d’Alzheimer sont les cibles à la fois de stéréotypes liés à l’âge, mais aussi de stéréotypes liés à cette maladie (Sartorius, 2003). Leur aidant familial est également souvent touché par l’image négative de la pathologie que les stéréotypes imputent à leur proche (Werner, 2008). Aussi, cette recherche a pour objectif de mieux connaître le point de vue d’aidants familiaux sur la maladie d’Alzheimer et le vieillissement, pour mieux appréhender les implications de ces représentations sur leur vécu. METHODE Un ensemble de questionnaires, dont des mesures de la vision du vieillissement (FSA-R ; Boudjemadi & Gana, 2009) et de la maladie d’Alzheimer (FS-ADS ; Werner et al., 2011), ont été administrés à 38 aidants familiaux dont le proche est atteint de la maladie d’Alzheimer ou d’une démence apparentée. RESULTATS Les analyses statistiques montrent que les individus qui présentent une vision négative du vieillissement sont ceux qui sont aidants depuis plus longtemps. Par ailleurs, les personnes qui ont un vécu négatif de la maladie (qui ont honte de leur proche ou qui sentent que les autres ont honte de lui), sont ceux qui se sentent moins compétents en tant qu’aidant. De même, le fait d’avoir peur de son proche, est associé à un épuisement physique et émotionnel, ainsi qu’à une humeur triste et anxieuse. CONCLUSION Les stéréotypes liés à l’âge et à la maladie péjorent plusieurs éléments du vécu de l’aidant (santé, sentiment de compétence, expérience en tant qu’aidant.). En conséquence, il importe d’encourager la déconstruction des stéréotypes et idées reçues véhiculés par la société, notamment par le biais de programmes d’aide aux aidants [less ▲]

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See detailTest of humic substances on in vitro roots initiation using isolated leaves of woody species
Tahiri, Abdelghani ULg; Destain, Jacqueline ULg; Thonart, Philippe ULg et al

Poster (2014, May 15)

Arise from the chemical and biological degradation of plant and animal residues and from the synthetic activities of microorganisms in the soil, humic substances (HS) are natural heterogeneous aromatic ... [more ▼]

Arise from the chemical and biological degradation of plant and animal residues and from the synthetic activities of microorganisms in the soil, humic substances (HS) are natural heterogeneous aromatic and organic compounds. These substances are chemically complex with no clearly defined chemical structure, although generalized models have been proposed and they can be divided into fractions of humic acids, fulvic acids and humins depending on their solubility in water as a function of the pH. The stimulation of plant growth and development by HS are the activities that have attracted the attention of many scientists. They influence plant productivity directly by the stimulation of biochemical and metabolic processes or indirectly through the modification of soil characteristics and microflora activities. All together, these properties mainly affect root architecture. By inducing root hairs proliferation, differentiating root cells and enhancing lateral root emergence, an increase of the total root biomass is observed. Experiments targeting the rooting stages in absence of interferences were conducted in vitro using HS extracted from landfill leachate and a stable commercial formulation (“Humifirst” from TRADECORP company: 12% humic acid and fulvic acid 3%) issued from leonardite. Shoots and leaves explants of silver birch (Betula pendula Roth) and black alder (Alnus glutinosa L. Gaertn) vitro-plants were treated with 10 ppm leachate HS and 100 ppm Humifirst HS for 5 days during the rooting induction/initiation phase. The treated explants were then transferred into elongation medium containing only nitrate calcium for 4 weeks. The results show that application of HS during the root induction/initiation phase did not significantly influence root growth of both species in comparison with control explants. [less ▲]

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See detailPerception of climate change and adaptation strategies in the drylands of West Africa : A review
De Longueville, Florence ULg; Ozer, Pierre ULg; Vigil, Sara ULg

Poster (2014, May 15)

The perception of climate change has become an exiting new field of research explored in recent years. This is a response from the international scientific community to the conclusions of the 4th report ... [more ▼]

The perception of climate change has become an exiting new field of research explored in recent years. This is a response from the international scientific community to the conclusions of the 4th report of the Intergovernmental Panel on Climate Change which had underlined serious deficiencies in this field, particularly in West Africa where population is largely dependent of rain-fed agriculture. Yet, a global survey of the literature since 2000 shows that most references on this topic were published over the last five years. [...] [less ▲]

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See detailQualitative and quantitative analyses of a pharmaceutical formulation produced by hot melt extrusion using Raman spectroscopy
Netchacovitch, Lauranne ULg; De Bleye, Charlotte ULg; Sacre, Pierre-Yves ULg et al

Poster (2014, May 15)

In the pharmaceutical industry, Hot Melt Extrusion (HME) is a recent technique used to integrate poor water soluble drugs in pharmaceutical formulations. Indeed, more and more active pharmaceutical ... [more ▼]

In the pharmaceutical industry, Hot Melt Extrusion (HME) is a recent technique used to integrate poor water soluble drugs in pharmaceutical formulations. Indeed, more and more active pharmaceutical ingredients (API) belong to the Biopharmaceutical Classification System (BCS) II and IV. Their integration in pharmaceutical solid forms is a big deal. HME processes increase the bioavailability and the solubility of those API by encompassing them in a polymeric carrier and by forming solid dispersions [1]. Moreover, in 2004, the FDA’s guidance initiative promoted the usefulness of Process Analytical Technology (PAT) tools when developing a manufacturing process. Vibrational spectroscopy is an appropriate PAT tool to analyze extrudates [2 – 3]. In this case, Raman spectroscopy, which belongs to vibrational spectroscopy, was used to analyze itraconazole extrudates qualitatively and quantitatively. During HME, the main objective is to develop solid dispersions by converting a crystalline API in an amorphous one, in order to improve its solubility and bioavailability [4]. According to Raman spectra, it is possible to identify the polymorphic form of the components in the extrudates by integrating or rationing the Raman bands that are characteristic of the API or by calculating the width at half intensity of some bands [5]. After determining the polymorphic form of the API, a quantitative method was developed in order to measure the ratio between the API and the polymer. Finally, chemical imaging was performed on extrudates to identify the distribution of the homogeneity of the API inside the polymer [6]. In conclusion, Raman spectroscopy is an appropriate tool to follow an extrusion process. By qualitative and quantitative analyses it is possible to determine the composition, the polymorphic form, the homogeneity, and the concentration of pharmaceutical matrices according to Raman fingerprint. References: [1] S. Shah et. al., Int J Pharm 453 (2013) 233 – 252. [2] L. Saerens et. al., Anal Chem 85 (2013) 5420 – 5429. [3] T. De Beer et. al., J Pharm Biomed Anal 48 (2008) 772 – 779. [4] A. Sarode et. al., Eur J Pharm Sci 48 (2013) 371 – 384. [5] E. Widjaja et. al., Eur J Pharm Sci 42 (2011) 45 – 54. [6] J. M. Amigo, Anal Bioanal Chem 398 (2010) 93 – 109. [less ▲]

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See detailIdentifying root-secreted proteases in Arabidopsis thaliana: an Activity-Based Protein Profiling approach.
Lallemand, Jérôme ULg; Périlleux, Claire ULg; Tocquin, Pierre ULg

Poster (2014, May 15)

Proteases are involved in many physiological processes during the whole life of the plant, such as embryonic development, defense against pathogens, nutrition or mycorrhiza creation. However, the ... [more ▼]

Proteases are involved in many physiological processes during the whole life of the plant, such as embryonic development, defense against pathogens, nutrition or mycorrhiza creation. However, the functions of many of the 800 proteases of Arabidopsis thaliana still remain unknown. Besides discovering new functions, studying proteases can also result in improving plant biotechnology. Indeed, plants can be used as hosts for recombinant protein production. Some proteins of interest require to be secreted in order to fold properly, but production yields are limited due to their degradation by endogenous extracellular proteases. The aim of our study is to identify active root-secreted proteases of Arabidopsis thaliana. Their activity was first analyzed by in vitro incubation with a target protein (BSA) at different values of pH and in the presence of proteases inhibitors. This analysis identified serine proteases as the major protease class involved in BSA degradation. Then, an Activity-Based Protein Profiling approach led to the labeling of two active serine proteases in the root-secreted sample. Finally, a further step towards the identification by mass spectrometry, based on affinity purification, was developed. [less ▲]

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See detailThe effects of flowering signals on root architecture in Arabidopsis
Mathieu, Laura ULg; Lobet, Guillaume ULg; Périlleux, Claire ULg

Poster (2014, May 15)

Roots are responsible for water and nutrient uptake and hence are critical to sustain the whole plant life cycle. This study aims at characterizing how root development is affected by flowering. We ... [more ▼]

Roots are responsible for water and nutrient uptake and hence are critical to sustain the whole plant life cycle. This study aims at characterizing how root development is affected by flowering. We therefore focused on the effects of systemic signals produced in the leaves at floral transition, namely the proteins FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF), on root growth and branching. These proteins act in the shoot apical meristem as potent promoters of flowering [1] but their effects in other parts of the plant are still unknown. [less ▲]

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See detailDevelopment of an analytical method to detect simultaneously bisphenols using a multiplexed surface-enhanced Raman scattering quantitative approach
De Bleye, Charlotte ULg; Dumont, Elodie ULg; Sacre, Pierre-Yves ULg et al

Poster (2014, May 15)

Over the last decade, bisphenol A (BPA) attracted a lot of attention. This molecule, commonly used as a precursor to produce epoxy-resin and plastics, is an endocrine disruptor presenting an estrogenic ... [more ▼]

Over the last decade, bisphenol A (BPA) attracted a lot of attention. This molecule, commonly used as a precursor to produce epoxy-resin and plastics, is an endocrine disruptor presenting an estrogenic activity [1]. Despite its health toxicity, BPA is present in a broad variety of consumer goods released from plastic bottles and packaging for example. Since the discovery of its adverse health effect of BPA, the manufacturers tend to use structural analogues of BPA such as BPS, BPF and BPB to produce plastic materials [2]. However, the health safety of these molecules is still not demonstrated. Currently, bisphenols are actively researched and quantified using solid phase extraction and chromatography techniques which are time and solvents consuming. Therefore, it could be very interesting to quantify simultaneously bisphenols using a fast and “green” technique. Surface-enhanced Raman scattering (SERS) exalts dramatically the Raman scattering of molecules adsorbed or very closed to metallic surface enabling to detect very low amounts of analytes while keeping the structural information obtained from the spectrum which is very interesting to consider multiplexed analyses [3-4]. Moreover, SERS, which is a solvent free and fast acquisition technique, is an attractive tool in “Green Chemistry” [5]. In this context, the development of a multiplexed quantitative approach to detect bisphenol was considered. Silver nanoparticles (AgNps) were selected as SERS substrate and their functionalization was investigated taking into account the weak affinity of phenolic molecules for gold and silver surface [6]. Pyridine was selected as surface modifier and allowed to attract bisphenols around metallic surface thanks to hydrophobic interaction and hydrogen bonds [7]. Afterwards, the SERS samples preparation was optimized playing on the concentrations of pyridine and aggregating agent used to get the nanoparticles closer to each other which promotes the SERS effect. Tap water samples were spiked with different concentration of BPA from 5 ppb to 1000 ppb and analyzed using the optimized SERS sample preparation. A good linearity of the response was observed and a calibration curve with coefficient of determination (R2) of 0.9922 was obtained by plotting the intensity of a principal band of BPA versus the concentration. This last step was repeated using BPB as analyte and a calibration curve with a R2 of 0.9991 was obtained for the same range of concentration using a specific band intensity of BPB. Finally, tap water samples were spiked with different concentrations of BPA and BPB simultaneously and analyzed using SERS and it was possible to detect selectively the two molecules thanks to specific bands and a good linearity of the response was observed for both. To conclude, promising results were obtained which pave the way to “green” multiplexed quantitative analyses of very low concentrated analytes using SERS. References: [1] J.-H. Kang et al., Toxicology 226 (2006) 79-89 [2] C. Liao et al., J. Agric. Food Chem. 61 (2013) 4655-4662 [3] K. Kneipp et al., Chem. Rev. 99 (1999) 2957-2975. [4] R.F. Aroca et al., Adv.Colloid Interface Sci. 116 (2005) 45-61. [5] C. De Bleye et al., Talanta 116 (2013) 899-905. [6] X.X. Han et al., Anal. Chem., 83 (2011) 8582-8588. [7] B. San Vicente et al., Anal. Bioanal. Chem. 380 (2004) 115-122. [less ▲]

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See detailAdaptation to beach erosion in the African coastal cities: from the procrastination by the Government to the forced migration of the most precarious population. The case of Cotonou, Benin
Ozer, Pierre ULg; De Longueville, Florence ULg; Hountondji, Yvon Carmen et al

Poster (2014, May 14)

This analysis shows that the current impacts of geomorphological changes result mainly from the sum of human activities. However, it is necessary to consider the risk of coastal erosion and forced ... [more ▼]

This analysis shows that the current impacts of geomorphological changes result mainly from the sum of human activities. However, it is necessary to consider the risk of coastal erosion and forced migration (of mostly poor people) in the coming decades with the amplification of sea level rise due to global warming. [less ▲]

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See detailImproving soil conservation through an adapted tillage: experience from the cultivation of potatoes in Bamiléké's hills of Cameroon
Djoukeng, Henri Grisseur ULg; Tankou, Christopher Mubeteneh; Degré, Aurore ULg

Poster (2014, May 14)

The western highlands of Cameroon are an area where the population density and growth rates are the highest in the country. In this region, the main activity is agriculture, and rivers are the main source ... [more ▼]

The western highlands of Cameroon are an area where the population density and growth rates are the highest in the country. In this region, the main activity is agriculture, and rivers are the main source of safe drinking water. Lacks of arable land and especially against very complex land tenure, farmers are increasingly exploiting the hills (9-30 % slope) for the production of vegetable crops, mainly potatoes. The methods of preparation of soil found there are ridging in the direction of the slope and the culture dish. These practices promote erosion by runoff, generally compromises the multiple functions of agriculture, and in particular the environmental function (soil degradation, pollution and silting up of rivers) and the production function (incomes). In order to ensure soil stability and maintain good water quality of rivers, we put it up a new way of preparing the ground: the tied ridging. To quantify the effectiveness of the latter, we conducted tests of erosion by runoff with Wischmeier’s plots on the most exploited slopes, namely 11% and 29%. The run-off water and sediments were collected per plot and per block after every rain. The first analyses show that there is a significant difference between the culture dish or ridging along the slope and tied ridging. The major constraint of this practice lies in the increase of about 17% of the labor. Tied ridging reported losses in average land 16% lower compared with the ridging in the direction of the slope and 22% compared with the culture dish, he also presented higher yields of 65 % compared with the culture dish and the ridging in the direction of the slope. Despite the hardship, the test results have convinced the participants and some curious farmers which have adopted the technology during the next growing season. [less ▲]

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See detailBelgian Grasshoppers: A Nutritious Food Source
Paul, Aman ULg; Frederich, Michel ULg; Blecker, Christophe ULg et al

Poster (2014, May 14)

Rapid urbanization and rising economies are creating shifts in the composition of global food demand, so it is necessary to explore new sources of food with better nutritional profile. Among the ... [more ▼]

Rapid urbanization and rising economies are creating shifts in the composition of global food demand, so it is necessary to explore new sources of food with better nutritional profile. Among the alternative food that exists are the grasshoppers, about 80 species of which are consumed worldwide. Grasshoppers are not only rich source of proteins and lipids but also some important minor component like vitamins and minerals. Edible species of grasshopper in Belgium were identified and attempts were made for the lab rearing of meadow grasshopper (Chorthippus parallelus). The lipids as well as protein contents of meadow grasshopper (Chorthippus parallelus) & long winged conehead (Conocephalus discolor) were investigated. The fatty acid compositions of these two species were determined by gas chromatography. Some of the physicochemical properties of the lipids extracted were also analyzed. These two grasshopper species could be really nutritious source of food. [less ▲]

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See detailMicroplastics contamination in two planktivorous and commercial fish species
Collard, France ULg; Parmentier, Eric ULg; Das, Krishna ULg

Poster (2014, May 13)

Plastic pollution is a huge environmental concern and affects each marine ecosystem. Plastics are produced by millions of tonnes each year in the world and finally accumulate in oceans. They adsorb many ... [more ▼]

Plastic pollution is a huge environmental concern and affects each marine ecosystem. Plastics are produced by millions of tonnes each year in the world and finally accumulate in oceans. They adsorb many persistent organic pollutants, cause external and internal wounds and provoke blockage of the digestive tract of marine mammals, birds and turtles. Plastics can also threaten marine organisms of small size class in the same way by fragmenting in smaller parts that result in microplastics of less than five millimetres. These microplastics are of the same order of magnitude than plankton and can thus be ingested by filter-feeders, suspension-filters and planktivorous organisms such as fish. Few studies deal with microplastics ingestion by fish and even less by commercial fish species. The herring (Clupea harengus) and the sardine (Sardina pilchardus) were respectively the third and the eighth most caught fish species in the world in 2009. We focused our research on these two species which are of economic importance. We sampled around thirty individuals of each species in the Channel and in the North Sea in January 2013. The stomach contents were digested by sodium hypochlorite and then analyzed. Microplastics were characterized by size, colour and shape. The results of these analyses will highlight the need for studies about microplastics ingestion by planktivorous species. [less ▲]

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See detailTrace element bioaccumulation in rope-grown Mytilus galloprovincialis: knowledge update
Richir, Jonathan ULg; Gobert, Sylvie ULg

Poster (2014, May 12)

Numerous trace elements (TEs) can be considered as potential pollutants of the environment, their mining productions and industrial uses increasing worldwide. Their monitoring can be achieved through the ... [more ▼]

Numerous trace elements (TEs) can be considered as potential pollutants of the environment, their mining productions and industrial uses increasing worldwide. Their monitoring can be achieved through the use of bioindicator species, such as the Mediterranean mussel Mytilus galloprovincialis (Lamarck, 1819). That species has been widely used to monitor the chemical pollution of coastal ecosystems by Cr, Ni, Cu, Zn, Cd, Pb, As, Ag and V. Conversely, environmental levels of Be, Al, Fe, Mn, Co, Se, Mo, Sn, Sb and Bi have been little or not monitored so far in mussel watch programs. Bioaccumulation processes of these 19 TEs in rope-grown M. galloprovincialis purchased from a salt pond with good chemical water quality were thus investigated in the present study. Mussels efficiently accumulated the 19 studied TEs. Bioaccumulation processes were driven by numerous mutually dependent biological parameters such as the mussel size and flesh weight, the sex and the reproductive status and the body compartment considered. TE bioaccumulation was a power function of the mussel soft body dry weight; total contents linearly increased with the shell length. Small-size mussels overall concentrated more TEs, with a high interindividual variability, consequently influencing the modelling of their bioaccumulation in the whole rope population. Although a large range of rope-grown M. galloprovincialis sizes can be used for monitoring purposes, one will thus take care not to use extreme size individuals. The influence of gametogenesis in determining female body higher TE concentrations prior to spawning could not be neglected and varied depending on the element. TEs were preferentially accumulated in the hepatopancreas, except for Zn, Se, Cd and Mo, more concentrated in gills. Gametogenesis did not influence TE distribution between body compartments, but likely diluted their concentrations as a direct consequence of massive reproductive tissue production. So, results from the present study underlined the potential use of M. galloprovincialis in the biomonitoring of numerous little studied TEs and gave some insights into the decisive role played by some relevant biological parameters in bioaccumulation processes of the 19 investigated TEs in rope-grown mussels. [less ▲]

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See detailModeling using the SWAT model of water flow and transport in suspension in the watershed of the valley of Wadi El-Hachem
Tadrist, Nassima ULg; DEBAUCHE, OLIVIER ULg; Degré, Aurore ULg et al

Poster (2014, May 12)

In the Maghreb, dams regularly suffer from excessive siltation due to erosion problems present in the catchment areas. The origins of this erosion are multiple: land use, deforestation, land affectation ... [more ▼]

In the Maghreb, dams regularly suffer from excessive siltation due to erosion problems present in the catchment areas. The origins of this erosion are multiple: land use, deforestation, land affectation , ... Hydrology coupled with geographic information systems allows using distributed and physically based models to predict the evolution of siltation of dams. The application of these models in Algeria will finally predict the impact of anti-erosion measures, land use patterns on the siltation of dams accurately estimating the amount of sediment produced by erosion runoff and the degree of filling. A methodology based on the map data (digital terrain model, map soil science, geology map and mapping of land use) and daily meteorological data (temperature, relative humidity, wind speed, solar radiation) is being development and testing of the dam Bourkourdane. The SWAT model is used to predict the amount of sediment accumulating in the dam, the water flow rate inbound, outbound, and the volumes of water and sediment stored in the dam. Adequate management of releases, coupled with better management of erosion upstream of the dam will extend the life of dams Algerians. Especially for Boukourdane, improved management of releases is paramount to improve groundwater recharge, fight against the intrusion of marine waters and prevent the accumulation of fine particles that reduce soil permeability. [less ▲]

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