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See detailA plea for the creation for inviolate areas to protect reference areas for future microbiology research in Antarctica
Wilmotte, Annick ULg; Willems, Anne; Verleyen, Elie et al

Poster (2015, September 08)

Antarctica is essentially a microbial continent. A surprisingly large biodiversity of adapted microorganisms lives permanently in various biotopes of the ice-free areas (about 44,000 km2). Based on ... [more ▼]

Antarctica is essentially a microbial continent. A surprisingly large biodiversity of adapted microorganisms lives permanently in various biotopes of the ice-free areas (about 44,000 km2). Based on molecular methods and microscopic observations, important findings like the presence of potentially endemic taxa, their survival in glacial refugia since the continent moved away from Australia and South America, and the determination of biogeographic patterns have been inferred. Moreover, Antarctic microorganisms may contain novel molecules with potentially pharmaceutical or biotechnological interest. However, microbial habitats are under pressure as a result of nthropogenic introductions. Indeed, as a consequence of human presence, non-indigenous microorganisms are released from bodies, clothing, cargo and food into the environment (Cowan et al. 2011). The increase of tourism and its diversification from coastal cruises to adventurous expeditions into the continent, as well as the increase of research stations and associated impacts, constantly create new ‘entry points‘ for microbial contamination (Chown et al. 2012). The impacts of such introductions are still unknown, and might lead to a loss of the native microbial biodiversity, or its modification by lateral gene transfer. The technical progresses in molecular methodologies, like we currently see with Next Generation Sequencing (NGS), mean that very sensitive high-throughput analyses will become increasingly accessible. They have the potential to describe the microbial communities with unprecedented details without preconceived expectations. However, by that time, we might have lost the pristine Antarctic areas that would enable the scientists to study the native microbial flora, its functioning and properties. The Protocol on Environmental Protection of the Antarctic Treaty foresees the designation of Antarctic Specially Protected Areas (ASPA) to protect “outstanding environmental, scientific, historic, aesthetic, or wilderness values, any combination of those values, or on- going or planned scientific research” (http://www.ats.aq/e/ep_protected.htm). However, the designation of ASPAs has not followed a systematic planning, and often focused on the conservation of large animals or higher plant communities. Microorganisms have the handicap of generally being invisible without a microscope and relevant expertise, and needing molecular methods to determine their identity. Terrestrial habitats are protected in 55 out of the 72 existing ASPAs (in total less than 700 km2), mostly based on the need to protect vascular plants and bryophyte communities (Shaw et al. 2014). In 28 ASPAs, the protection targets the lichens, whereas microalgae are protected in 16 ASPAs, cyanobacteria in 7 and snow microalgae in 3. Only 8 ASPAs mention ‘Microbial habitats’, ‘microbial communities’ or ‘soil and lake microflora’. One tool of the Protocol that could be specifically used to protect microbial habitats is the creation of inviolate areas where no visitation is permitted (inside ASPAs, for example). These zones could be set aside for future research (Hughes et al. 2013) and become extremely valuable. After a few decades, they would be unique examples of truly pristine habitats, representative of the native microbial diversity and processes. Such an option would necessitate discussions and consensus with scientists of other disciplines to select these regions, and careful management protocols of the sites and their vicinity (Hughes et al. 2015). In addition, gaps in knowledge should be addressed, like the extent of transportation of microorganisms by natural means (winds, birds...) (e.g. Pearce et al. 2009), and the probability of subsequent colonization of new areas by microorganisms coming from other Antarctic regions or from outside Antarctica. Let’s hope that the dialogue between scientists and policy makers will enable to improve the conservation of Antarctic microbial diversity and safeguard the possibility to study these unique communities in the future with the most advanced techniques of the time. The outcome of these discussions might also be of interest for Arctic and alpine regions. [less ▲]

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See detailThe leaders profile method: detection of distinct processes in a signal
Kleyntssens, Thomas ULg; Nicolay, Samuel ULg

Poster (2015, September 08)

The leaders profile method is a multifractal formalism that allows to compute non-concave and non-increasing spectra. Our implementation can detect the presence of distinct processes in a signal. We ... [more ▼]

The leaders profile method is a multifractal formalism that allows to compute non-concave and non-increasing spectra. Our implementation can detect the presence of distinct processes in a signal. We present here the first results obtained. [less ▲]

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See detailA wavelet-based mode decomposition compared to the EMD
Deliège, Adrien ULg; Nicolay, Samuel ULg

Poster (2015, September 08)

We introduce a new method based on wavelets for decomposing a signal into quasi-periodic oscillating components with smooth time-varying amplitudes. This method is inspired by both the "classic" wavelet ... [more ▼]

We introduce a new method based on wavelets for decomposing a signal into quasi-periodic oscillating components with smooth time-varying amplitudes. This method is inspired by both the "classic" wavelet-based decomposition and the empirical mode decomposition (EMD). We compare the efficiency of the method with the well-established EMD on toys examples and the ENSO climate index. [less ▲]

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See detailBIOGEOGRAPHIC PATTERNS IN ANTARCTIC LACUSTRINE PROKARYOTES
Tytgat, Bjorn; Verleyen, Elie; Sweetlove, Maxime et al

Poster (2015, September 07)

Amplified climate change, increased human activity and the introduction of alien species likely form the biggest threat to Antarctic terrestrial ecosystems through range size expansions and contractions ... [more ▼]

Amplified climate change, increased human activity and the introduction of alien species likely form the biggest threat to Antarctic terrestrial ecosystems through range size expansions and contractions, regional extirpation and impacts on ecosystem functions. Despite their crucial role in the functioning of Antarctic terrestrial ecosystems , little is known about the present -day diversity and biogeography of microorganisms such as prokaryotes and microeukaryotes in the Antarctic Biogeographic Realm. Furthermore, identification of the key processes underlying microbial biodiversity dynamics is essential to understand and predict the consequences of global change on Antarctic lacustrine ecosystems. We analysed bacterial biodiversity in a total of 152 lacustrine microbial mat samples, distributed over the three main Biogeographic regions in the Antarctic Realm, including continental Antarctica, Maritime Antarctica and the Sub-Antarctic Islands comprising the southern Indian Ocean Province (SIOP) and the southern Pacific Ocean Province (SPOP). We targeted the V1-V3 variable regions of the 16S rRNA gene. Amplicon sequencing was done on an Illumina PE300 MiSeq. Sequences were processed using Usearch and Uparse, Mothur and custom scripts for basic parsing. An OTU cut-off was defined at 97 % sequence similarity, and sequences were mapped against a local GreenGenes database. Downstream analyses were performed using several R packages. We obtained about three million high quality sequences, with an average length of 500 bp. Sequences belonged to 8237 OTUs, and were distributed over 51 phyla and 366 genera. In addition, 649 OTUs remained unclassified at the phylum level and 6263 at the genus level. Mean OTU richness differed strongly between the four biogeographic regions. The lakes from Maritime Antarctica had a higher richness than those from Continental Antarctica. Interestingly, in sub-Antarctica OTU richness was strongly variable, with Marion Island (SIOP) having the lowest and Macquarie Island (SPOP) having on average the highest diversity of all studied regions. Multivariate Analyses showed that microbial community composition varied between biogeographic regions, with Macquarie Island being most different from the other regions. Continental Antarctica, Maritime Antarctica and the lakes from the SIOP share many OTUs, both in the case of Cyanobacteria and other bacteria, but are also characterised by a considerable number of unique OTUs. Within Antarctica, some regions harbour distinct bacterial communities such as the lakes in Schirmacher Oasis, Dronning Maud Land, and those from the eastern and western part of the Antarctic Peninsula. [less ▲]

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See detailThe BCCM/ULC culture collection to conserve, document and explore the polar cyanobacterial diversity
Wilmotte, Annick ULg; Renard, Marine ULg; Kleinteich, Julia et al

Poster (2015, September 07)

In Polar Regions, Cyanobacteria represent key primary producers and are the main drivers of the food webs in a wide range of aquatic to terrestrial habitats. For example, they form benthic microbial mats ... [more ▼]

In Polar Regions, Cyanobacteria represent key primary producers and are the main drivers of the food webs in a wide range of aquatic to terrestrial habitats. For example, they form benthic microbial mats in lakes and soil crusts in terrestrial biotopes. They have adapted to their environment, and may present interesting features to survive freeze/thaw cycles, seasonally contrasted light intensities, high UV radiations, dessication and other environmental stresses. The BCCM/ULC public collection funded by the Belgian Science Policy Office since 2011 aims to gather a representative portion of the polar cyanobacterial diversity with different ecological origins (limnetic microbial mats, soil crusts, cryoconites, endoliths, etc.). The collection is available for researchers to study the taxonomy, evolution, adaptations to extreme environmental conditions, and genomic make-up. It presently includes 200 cyanobacterial strains, with 123 being of polar origin (catalogue: http://bccm.belspo.be/catalogues/ulc-catalogue-search). The morphological identification shows that the strains belong to the orders Synechococcales, Oscillatoriales, Pleurocapsales, Chroococcidiopsidales and Nostocales. The large diversity is also supported by the phylogenetic analyses based on the 16S rRNA sequences. This broad distribution makes the BCCM/ULC collection particularly interesting for phylogenomic studies. To this end, the sequencing of the complete genome of 16 selected strains is currently under way. In addition, cyanobacteria produce a wide range of secondary metabolites (e.g. alkaloides, cyclic and linear peptides, polyketides) with different bioactive potential (e.g. antibiotic, antiviral, anticancer, cytotoxic, genotoxic). Bioassays have shown antifungal activities of the cell extracts from strains Plectolyngbya hodgsonii ULC009 and Phormidium priestleyi ULC026. The potential of the polar strains to produce cyanotoxins and other secondary metabolites is currently being studied by ELISA, LC-MS and the detection of genes involved in their production. Due to the geographic isolation and the strong environmental stressors of the habitat, the exploration of these metabolites in Antarctic cyanobacterial strains seems promising for biotechnology or biomedical applications (Biondi et al. 2008). In summary, the BCCM/ULC public collection could serve as a Biological Resource Centre (OECD 2001) to conserve and document the biodiversity of polar cyanobacteria, as well as a repository for discovery of novel bioactive compounds. REFERENCES Biondi, N., Tredici, M., Taton, A., Wilmotte, A., Hodgson, D., Losi, D., & Marinelli, F. (2008) : Cyanobacteria from benthic mats of Antarctic lakes as a source of new bioactivities. Journal of Applied Microbiology, 105(1) : 105- 115 OECD (2001) Biological Resource Centres : Underpinning the Future of Life Sciences and Biotechnology. http://www.oecd.org/science/biotech/2487422.pdf [less ▲]

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See detailCHARACTERIZATION OF TEN STRAINS OF FILAMENTOUS CYANOBACTERIA FROM THE SOUTH SHETLAND ISLANDS, MARITIME ANTARCTICA
Kovacik, Lubomir; Pereira, Antonio; Dusinsky, Roman et al

Poster (2015, September 07)

The evolutionary relationships of ten Antarctic cyanobacterial strains of the order Oscillatoriales isolated from King George Island and Deception Island, South Shetland Islands were studied by a ... [more ▼]

The evolutionary relationships of ten Antarctic cyanobacterial strains of the order Oscillatoriales isolated from King George Island and Deception Island, South Shetland Islands were studied by a polyphasic approach. Phenotypic observations of the morphological features and genotypic analyses (16S rRNA and ITS sequences) were performed. Based on major phenotypic features, the strains were divided into four distinct morphotypes: Leptolyngbya borchgrevinkii (A), Leptolyngbya frigida (B), Phormidium autumnale (C) and Wilmottia murrayi (D). This morphological identification was in global agreement with the evolutionary relationships. According to the phylogenetic analysis, the ten strains were divided into two major clades, containing related strain sequences with Leptolyngbya morphotypes in one clade and with morphotypes corresponding to Phormidium, Wilmottia and Microcoleus spp. in the other clade. Each major clade was divided into two sub-clades. For the first time, the 16S rRNA gene sequence of a strain corresponding to the Leptolyngbya borchgrevinkii morphotype (A) was determined, on the basis of strain KOVACIK-ANT 1990/4. The closest sequence to our morphotype A is the clone Fr252 isolated from microbial mat of Antarctic Lake Fryxell. Morphotype B is closest to sequences assigned to Leptolyngbya frigida isolated from microbial mats of lakes in continental East Antarctica. Morphotype C belongs to a cluster including strains with morphotypes corresponding to Phormidium autumnale from Antarctica, but also from Europe. Morphotype D is grouped with sequences of the morphotype assigned to Wilmottia murrayi isolated from Antarctica. [less ▲]

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See detailBEDROCK AND BIOTIC INFLUENCE ON COMMUNITY COMPOSITION IN SOILS FROM THE SØR RONDANE MOUNTAINS, EAST ANTARCTICA
Tytgat, Bjorn; Verleyen, Elie; D'hondt, Sofie et al

Poster (2015, September 07)

Antarctica is a continent of extremes; the low availability of liquid water and nutrients, extreme low temperatures and seasonally variable levels of solar radiation exert high selective pressures on ... [more ▼]

Antarctica is a continent of extremes; the low availability of liquid water and nutrients, extreme low temperatures and seasonally variable levels of solar radiation exert high selective pressures on organisms. Consequently, most life forms in the scarce ice-free regions which represent less than 1% of the surface area of the continent are microbial. Despite this, terrestrial microbial communities are poorly studied and the existing data are geographically focused on McMurdo dry valleys and volcanically active regions. Nunataks, mountain tops protruding through the ice sheets, occur along much of the East Antarctic coast and in the Transantarctic Mountains. Among them, several remained ice-free during Neogene and Pleistocene ice ages and thus may have acted as important refugia for terrestrial life. Here we present the results of a broad-scale survey of microbial biodiversity of ice-free regions in the western Sør Rondane Mountains (Dronning Maud Land (DML), East Antarctica). A total of 66 samples from eight different ice-free regions were selected to represent gradients in bedrock type (gneiss or granite), the macrobiotic content (presence or absence of moss, lichen and/or arthropods) and geographic location. All samples were subjected to both genetic fingerprinting (ARISA) and second generation sequencing (Illumina MiSeq 300PE) targeting the V1 -V3 variable regions of the 16S rRNA gene. Mock communities were included to benchmark the bioinformatics pipeline. Reads were processed using Usearch (Edgar 2010), clustered based on a 97 % similarity cutoff using Uparse (Edgar 2013)and identified using the GreenGenes training set. The specific conductivity, pH, water content, and total (TC),total organic (TOC) and inorganic (IC) carbon content were determined and used as explanatory variables in direct ordination analyses of both the ARISA and the Illumina data. The Illumina sequencing resulted in ~600.000 high quality sequences divided over ~3980 OTUs in 28 phyla and 219 genera. No significant differences in richness equaling the number of OTUs after standardization for the number of sequences per samples were observed between high, medium and low TOC content classes for the sequencing data. Redundancy Analysis revealed that bedrock type (granite or gneiss), water content, specific conductance, pH and TOC significantly shaped the bacterial community composition. The ARISA dataset, despite having a lower taxonomic resolution, showed very similar patterns and relationships with environmental data, among which bedrock type remained the most important parameter in explaining differences in community structure between the samples. As the gneiss is supposedly of granite origin, differences in community structure may be related to physical differences between both bedrock types and their weathering products. Preliminary cosmogenic analysis of Pb isotopes of gravel samples indeed suggest a predominantly local origin of the material, yet mixtures with exotic material cannot be excluded in samples from gneiss outcrops. We conclude that microbial community composition is primarily driven by mineralogical characteristics of weathering products in these poorly developed soils, while biotic influences are of secondary importance. [less ▲]

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See detailEVALUATION OF SV2Alox/Cre TRANSGENIC MOUSE USING [18F]UCB-H IN IN VITRO AUTORADIOGRAPHY
Serrano Navacerrada, Maria Elisa ULg; Becker, Guillaume ULg; MENTEN, Catherine ULg et al

Poster (2015, September 04)

Background: SV2A is the most studied isoform of the Synaptic Vesicle 2 proteins, which are involved in the synaptic vesicle trafficking. Interestingly, the SV2A has been identify as the binding site for ... [more ▼]

Background: SV2A is the most studied isoform of the Synaptic Vesicle 2 proteins, which are involved in the synaptic vesicle trafficking. Interestingly, the SV2A has been identify as the binding site for the antiepileptic drug levetiracetam, showing a close relation between the epilepsy, the dysregulation of the SV2A levels and the response to antiepileptic medications. SV2A floxed-mice were developed using a cre-lox technique, leading to a strong decrease of SV2A expression in the CA3 field of the hippocampus. We aim here to validate this model using [18F]UCB-H, a novel PET imaging radiotracer with a nanomolar affinity for human SV2A. Methods: In vitro autoradiography were performed on SV2Alox/Cre+ transgenic mouse brain slices. SV2Alox/Cre- mouse was used as control. To obtain a structural reference, brain slices underwent eosin-haematoxylin staining. Images of both procedures were coregistered using π-PMOD software. Regions of interest (Dentate Gyrus, CA1, CA2 and CA3) were drawn according to a stereotaxic atlas of the mouse brain. Results: Analyses showed significant differences in radiotracer binding (p<0.001) between SV2Alox/Cre+ mouse and SV2Alox/Cre- mouse highlighting an important reduction for the labelling density in Ammon's horn, particularly in CA1, compared to Dentate Gyrus where the diminution was less marked. Conclusions: Here, we used the radiotracer [18F]UCB-H to probe the decreased expression of SV2A protein in the hippocampus of SV2Alox/Cre+ mouse versus SV2Alox/Cre- control mouse. Our results contribute to the validation of the model, and encourage us to proceed with further longitudinal and behavioural studies. [less ▲]

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See detailThe executive functioning in normal aging: Impact of the cognitive reserve
Simon, Jessica ULg; Gilsoul, Jessica ULg; Collette, Fabienne ULg

Poster (2015, September 04)

There exists a large inter-individual variability regarding the effects of aging on cognition. According to Stern (2009), people who developed a high level of reserve are more resilient to the effects of ... [more ▼]

There exists a large inter-individual variability regarding the effects of aging on cognition. According to Stern (2009), people who developed a high level of reserve are more resilient to the effects of aging that individuals with lower cognitive reserve. In this study, we describe the impact of cognitive reserve on executive functions in normal aging. Ninety healthy participants aged from 60 to 80 years were recruited. We assessed the three major executive functions: Inhibition (Stroop test, Hayling test, TAP Incompatibility subtest), Shifting (TAP Flexibility subtest, Plus-Minus task), and Updating (Letter-Number Sequencing subtest from MEM III, Letter memory task, 2-back task). Cognitive reserve was measured by questionnaires assessing educational level, occupation, leisure activities and physical activity across the life. Multiple linear regressions (p<0.05) adjusted for age, quality of sleep, processing speed showed that elderly with a high level of reserve have better performance on updating. We also assessed the effect of each factor of cognitive reserve separately after adjustment for the other. We observed that people with high level of education have better performance on flexibility (TAP Flexibility subtest and composite score) and on updating (Letter-Number Sequencing subtest, Letter memory and composite score). However, we didn’t observe any significant effect of the other factors of cognitive reserve. These results suggest that the cognitive reserve is related to abilities in some executive tests. [less ▲]

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See detailSelf-Reported Delinquency Survey: Comparison of Two Methods Among Female and Male Detained Adolescents
Grégoire, Julie ULg; Mathys, Cécile ULg

Poster (2015, September 04)

Self-report delinquency (SRD) surveys have begun to be used more than 70 years ago to measure delinquency (Porterfield, 1943). Since then, lots of methods have been developed (e.g. P&P questionnaire ... [more ▼]

Self-report delinquency (SRD) surveys have begun to be used more than 70 years ago to measure delinquency (Porterfield, 1943). Since then, lots of methods have been developed (e.g. P&P questionnaire, telephone interviewing, face-to-face interviewing, CASI, ACASI) for data collection (Kleck & Roberts, 2012). Although a lot of researches have assessed the participation rates of these methods, most of SRD surveys are submitted to non-detained adolescents . We have therefore noticed that those methods only allow us to know but little about the participation rate of young detainees and about their motivation to take part in a SRD survey. This research, which constitutes the pre-test of a further larger research, aims to: 1) Identify which method of SRD (comparing Paper & Pencil (P&P) questionnaire and Web questionnaire) has the highest participation rate and is the most attractive for young detained people, and if there are differences between boys and girls. 2) Determine the impact of an incentive on the motivation to participate in a survey, and if there are differences between boys and girls. As a result, we can observe that the SRD survey method doesn’t seem to have an influence on the participation rate of youth from detention centers. Nevertheless, the most attractive SRD survey method seems to be the Web one. As it is also less discouraging, it seems preferable to use this method with these adolescents whenever it is possible. Regarding the different kinds of incentives regularly used in research, their impact on the decision to take part in a survey turns out to be very weak, even nonexistent or negative. It appears that an incentive for juveniles placed in detention centers is inappropriate to increase their motivation to participate. [less ▲]

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See detailSeasonality in human cognitive brain responses.
Meyer, Christelle ULg; Muto, Vincenzo ULg; Jaspar, Mathieu ULg et al

Poster (2015, September 04)

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See detailThe impact of ageing on episodic memory encoding: an fMRI study
François, Sarah ULg; Angel, Lucie; SALMON, Eric ULg et al

Poster (2015, September 04)

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See detailLa Banque de Données des Epiclèses Grecques (BDEG) dans le cadre des Humanités numériques : questions théoriques et méthodologiques.
Lebreton, Sylvain ULg

Poster (2015, September 03)

Quiconque est un peu familier avec les textes grecs antiques peut aisément prendre la mesure de la richesse, en nombre et en diversité, des épiclèses (épithètes cultuelles) que les anciens Grecs ont ... [more ▼]

Quiconque est un peu familier avec les textes grecs antiques peut aisément prendre la mesure de la richesse, en nombre et en diversité, des épiclèses (épithètes cultuelles) que les anciens Grecs ont attribuées à leurs divinités. Cette importance, tant quantitative que qualitative, fait de ces dénominations un vecteur extrêmement pertinent pour l'étude du polythéisme hellénique, en même temps qu'elle constitue un défi analytique de premier ordre. Compte tenu de cette abondance, de la masse documentaire mise à contribution (surtout si l'on envisage le monde grec antique dans son ensemble), mais aussi de la complexité des relations entre les différentes composantes de la « société des dieux » des anciens Grecs, une telle étude peut tirer grand profit du recours à des outils de traitement quantitatif des données. Ce constat est à l'origine de la création, il y a une dizaine d'années, de la Banque de Données des Epiclèses Grecques (BDEG), dans le cadre du LAHM (ex-Crescam, UMR 6566 CReAAH) de l'Université Rennes 2 (https://epiclesesgrecques.univ-rennes1.fr/accueil.php). Le projet est toujours en cours de développement et constitue de ce fait une étude de cas potentiellement intéressante dans le cadre d'une réflexion sur les Humanités numériques dans le champ de l'Antiquité. En effet, la confrontation avec la réalité des données documentaires (en l'occurrence principalement littéraires et épigraphiques), les progrès dans la réflexion sur le traitement quantitatif et les évolutions des outils numériques ont rendu nécessaire l'évolution de la BDEG depuis sa création. On s'attachera donc à présenter certains pans de cette évolution – passés, en cours et à venir – en insistant sur les problèmes méthodologiques qu'ils posent du point de vue des Humanités numériques. [less ▲]

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See detailWhy are flux avalanches deflected by a metallic layer?
Brisbois, Jérémy ULg

Poster (2015, September 03)

Sudden avalanches of magnetic flux bursting into a superconducting sample are deflected from their trajectories when they encounter a conductive layer deposited on top of the superconductor. Remarkably ... [more ▼]

Sudden avalanches of magnetic flux bursting into a superconducting sample are deflected from their trajectories when they encounter a conductive layer deposited on top of the superconductor. Remarkably, in some cases the flux is totally excluded from the area covered by the conductive layer. Even if this phenomenon has been known for a few years, there is currently no theoretical model describing it. Moreover, the question whether the deflection would also be observed for a single vortex entering the region covered by a metallic layer is still unanswered. In this work we use the magneto-optical imaging (MOI) technique, based on the Faraday effect, to show that a conductive layer (Cu) can repel flux avalanches triggered in an underlying superconducting film (Nb) (see figure). We present a simple classical model that accounts for the deflection of a single vortex and considers a magnetic monopole approaching a semi-infinite conductive plane. This model suggests the important role played in the avalanche deflection by electromagnetic braking, arising from the eddy currents induced by the moving vortex in the metal. Moreover, we have found a decrease of the vortex damping coefficient due to the metallic sheet at large vortex velocities, correcting early theoretical descriptions where a linear behaviour was proposed. [less ▲]

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See detailIn vivo quantification of dopaminergic terminals loss in Parkinson’s Disease rat model: comparison between [18F]FMT and [18F]FDOPA.
Becker, Guillaume ULg; Bahri, Mohamed Ali ULg; Michel, Anne et al

Poster (2015, September 02)

Objectives: Rat models of Parkinson’s disease (PD), such as unilaterally lesioned rats with 6-hydroxydopamine (6-OHDA), are useful to evaluate novel antiparkinsonian therapies. MicroPET imaging, using L-3 ... [more ▼]

Objectives: Rat models of Parkinson’s disease (PD), such as unilaterally lesioned rats with 6-hydroxydopamine (6-OHDA), are useful to evaluate novel antiparkinsonian therapies. MicroPET imaging, using L-3,4-dihydroxy-6-[18F]-fluoro-phenylalanine ([18F]FDOPA) allows longitudinal evaluations of DA terminals loss. However, chemical structure of [18F]FDOPA leads to suboptimal PET imaging. 18F-fluoro-m-tyrosine ([18F]FMT) is an effective PET tracer to evaluate DA terminals integrity and L-aromatic amino acid decarboxylase (AAAD) metabolic pathway. So far, there are no available quantitative PET studies comparing the two methods in hemiparkinsonian rats. In this study, we compare imaging data provided by [18F]FMT PET and [18F]FDOPA PET in 6-OHDA-lesioned rats. Methods: 10 µg of 6-OHDA were injected into the right medial forebrain bundle (MFB) of male Sprague-Dawley rats (n=8). As control, sham-treated rats (n=8) were injected with vehicle only but otherwise treated identically. Striatal DA presynaptic activity was assessed by dynamic PET with both [18F]FMT and [18F]FDOPA. Structural T2-weighted brain images were acquired on a 9.4T MRI and were used for co-registration. After normalization on a MRI template, kinetic analysis was performed by “Patlak Reference” model, using PMOD software. Six days after the last PET scan, rats were sacrificed, and striatum were rapidly removed for striatal DA and metabolites quantification. Results: Striatal accumulation was observed for both tracers. However, while the administration of [18F]FDOPA required two peripheral inhibitors (benserazide and entacapone), only benserazide is needed with [18F]FMT. As consequence of the 6-OHDA-lesion, significant decrease of both [18F]FMT and [18F]DOPA accumulation was recorded in the striatum ipsilateral to the lesion. Lesioned rats had dramatically reduced uptake constant Ki in the ipsilateral striatum compared to the contralateral striatum (p<0.001 for [18F]FMT and p<0.05 for [18F]DOPA) and to the ipsilateral striatum of sham-treated rats (p<0.001 for both tracers). The DA content in the ipsilateral striatum was significantly lower (p<0.001) than in the contralateral striatum in the 6-OHDA-injected group, whereas such difference was not measured with the sham group. This indicate that [18F]FMT PET is as effective as [18F]DOPA PET to quantify loss of DA presynaptic function in unilaterally 6-OHDA lesioned rats. Conclusions: Our results are in agreement with data reporting correlation between these two tracers in a Non-human primate model of PD. The sensitivity of the data quantification obtained in this study, confirms the interest to pursue longitudinal investigations with [18F]FMT to monitor dopaminergic dysfunction in a more progressive preclinical model of PD. [less ▲]

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See detailOrbivirus screening on dried blood spots from captive oryx in United Arab Emirates stresses the importance of pre-import measures
Martinelle, Ludovic ULg; Haegeman, Andy; Lignereux, Louis et al

Poster (2015, September 01)

Objective: Following reintroduction and conservation programs of the Arabian oryx (Oryx leucoryx) and the scimitar horned oryx (SHO, Oryx dammah) in the United Arab Emirates (UAE), import of animals from ... [more ▼]

Objective: Following reintroduction and conservation programs of the Arabian oryx (Oryx leucoryx) and the scimitar horned oryx (SHO, Oryx dammah) in the United Arab Emirates (UAE), import of animals from wild game ranches in the United States of America (USA) is not uncommon. Bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) are orbiviruses that are the causative agents of bluetongue disease (BT) and epizootic hemorrhagic disease (EHD), respectively. BTV and EHDV are endemic in the UAE and the USA. Sheep and some wild ruminant species are usually severely affected by BT whereas EHD mostly affects wild animals and sometimes cattle. The objective of this study was to estimate the prevalence of these orbiviruses in Arabian and SHO from captive herds in the UAE using serology and molecular virology. Dry blood spot sampling for orbivirus screening is also discussed. Methods: A total of 175 SHO and 16 Arabian oryx were sampled. The latters were imported from Texas (USA) two weeks before sampling. All sampled animals belonged to captive herds spread over the Al Wathba area. For biosecurity reasons and to simplify blood storage, elutes from dried blood spot were used for serological and virological tests. Drops of about 80 µl of blood were dispensed on Whatman protein saver cards, and then allowed to dry in the dark at room temperature for 48 hours. Blood spots were punched out in paper discs with a 6 mm diameter punch and diluted in 250 µl PBS and Tween 20 0.05%. Eluted samples were incubated overnight at room temperature and then used immediately or stored at -80°C. To assess the most suitable ELISA kit to detect anti-BTV antibodies from the oryx discs, similar discs were prepared using blood issued from BTV seropositive and viremic as well as seronegative and non-viremic cattle. Elutes from discs with dried-blood from cattle were tested by BTV competitive ELISA (cELISA), sandwich ELISA (sELISA) and indirect ELISA (iELISA) and compared to cELISA performed directly on the serum of the same animals. iELISA on cattle paper discs gave the best correspondence with cELISA on cattle serum and was therefore used to test the oryx paper discs. Subsequently oryx paper discs were tested to detect antibodies against EHDV by cELISA. All the paper discs elutes from Arabian oryx and ELISA positive elutes from SHO were also tested by pan-BTV RTqPCR targeting a fragment of BTV segment 5 and detecting all BTV serotypes. Serotype specific end-point RT-PCR targeting a fragment of segment 2 of BTV2, BTV8, BTV10, BTV11, BTV13 and BTV17 were performed on pan-BTV positive samples. Results: Three out of 175 SHO and eight out of 16 Arabian oryx were found BTV seropositive by iELISA. None of the animals could be found seropositive against EHDV. BTV genome was detected in 1/3 seropositive SHO and in 5/16 of the Arabian oryx, amongst those 2/5 were seronegative. Overall Cq values were high (33-39). End point PCR failed to detect positive samples for any of the tested serotypes. Conclusion: BTV seroprevalence and RNA detection in SHO was very limited. By contrast BTV could be demonstrated in 5/16 imported Arabian oryx by molecular virology and in 8/16 by serology. The sampling was realized two weeks after the animals arrived in UAE and some oryx were viremic and seronegative, possibly suggesting a recent infection. Among the local SHO a low BTV seroprevalence was observed (3/175) and no animals were found positive to EHDV. This result was quite surprising because previous studies showed a higher BTV seroprevalence in domestic and wild ruminants of the Arabian Peninsula with wide local variations. In addition, dried blood spot testing has been demonstrated being a convenient and reliable method of sampling when storage conditions are hazardous. BTV serotypes could not be determined by end-point RT-PCR. At least 15 different BTV serotypes were reported in the USA and at least 10 in the Middle East, thus the oryx could be infected by a serotype not tested so far. Since RTqPCR positive values were high, the sensitivity of end-point RT-PCR might be insufficient to detect BTV out of eluted blood spots. Additional testing will be performed to identify the virus on the serotype level and therefore provide new insights to clarify the origin of the infection of the oryx. These results stress the need for pre-import risk assessment, precaution and implementation of biosecurity measures when considering translocation of wild ruminant species susceptible to BTV and EHDV. [less ▲]

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See detailParameter Identification Methods in a Model of the Cardiovascular System
Pironet, Antoine ULg; Desaive, Thomas ULg; Dauby, Pierre ULg et al

Poster (2015, September 01)

To be clinically relevant, mathematical models have to be patient-specific, meaning that their parameters have to be identified from patient data. To achieve real time monitoring, it is important to ... [more ▼]

To be clinically relevant, mathematical models have to be patient-specific, meaning that their parameters have to be identified from patient data. To achieve real time monitoring, it is important to select the best parameter identification method, in terms of speed, efficiency and reliability. This work presents a comparison of seven parameter identification methods applied to a lumped-parameter cardiovascular system model. The seven methods are tested using in silico and experimental reference data. To do so, precise formulae for initial parameter values first had to be developed. The test results indicate that the trust-region reflective method seems to be the best method for the present model. This method (and the proportional method) are able to perform parameter identification in two to three minutes, and will thus benefit cardiac and vascular monitoring applications. [less ▲]

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See detailRare recombination events and occurrence of superinfection exclusion during synchronous and asynchronous infection with homologous murine norovirus strains
Elisabetta, Di Felice; Ludwig, Louisa ULg; Toffoli, Barbara et al

Poster (2015, September 01)

Objective: Human noroviruses (HuNoVs) are recognised as one of the major global causes of non-bacterial gastroenteritis with significant morbidity and mortality in developing countries and a high economic ... [more ▼]

Objective: Human noroviruses (HuNoVs) are recognised as one of the major global causes of non-bacterial gastroenteritis with significant morbidity and mortality in developing countries and a high economic impact in developed countries. Spread primarily via the faecal-oral route, HuNoV infection is typically an acute self-limiting gastrointestinal illness. However, chronic HuNoV infection of immunocompromised persons has been identified as a persistent cause of disease and viral populations in such patients have been postulated as possible reservoirs for novel NoV variants. The Norovirus genus belongs to the Caliciviridae family of small, non-enveloped, positive sense, single-stranded RNA viruses. This genus is subdivided into at least six genogroups, which infect humans and various animal species. Until the recent report of low-level infection of cultured human B cells, no viable cell culture system existed for the study of HuNoVs. The robustness of this new cell culture system still poses a major hurdle, so that the murine norovirus (MuNoV), replicating efficiently in murine dendritic or macrophage cells, remains the model of choice for in vitro study of noroviruses. The molecular mechanisms driving viral evolution and specifically that of NoVs, are accumulation of point mutations and recombination, which enables the emergence of new combinations of genetic materials to generate potentially dramatic genomic changes in a recombinant NoV, which clusters within two distinct groups of NoV strains when two different genomic regions are phylogenetically analysed. The mechanism for NoV recombination is proposed to follow the copy-choice mechanism, involving a template shift during simultaneous replication of two strains infecting the same cell. Numerous NoV recombination events have been highlighted by in silico methods and the phenomenon has recently been shown in vitro with two homologous MuNoV strains. The object of this study was to qualitatively and quantitatively assess virus progenies generated by the use of different parameters of co- and superinfection of RAW264.7 cells with two homologous MuNoV strains (CW1 and Wu20) and thus help to specify important parameters for the occurrence of recombination events. As prerequisite for recombination events, co-and superinfection are of special interest in viral diseases, such as NoV, for which a persistent stage can be developed. Methods: Viruses and Cells Murine NoVs isolates CW1 and Wu20 were plaque purified and propagated in RAW 264.7 cells (ATCC TIB-71).Virus stocks were produced by infection of RAW 264.7 cells at an MOI of 0.05 and clarified by centrifugation. Passages 8 and 7 for CW1 and Wu20, respectively, were used for the experiments. Co-infection and superinfection experiments Monolayers of RAW 264.7 cells were infected with Wu20 at a MOI of 1 on ice. After 1 h, the Wu20 inoculums were removed and stored. The cells were washed twice with PBS and infected with CW1 at various MOI (0.1 ; 1 ; 10) and at various delays of co- or superinfection (0 min, 30 min, 1 h, 2 h, 4 h, 8 h, 12 h and 24 h). For co-infections, CW1 and Wu20 were simultaneously inoculated on the cells for 1 h on ice. Twenty-four hours after CW1 co- or superinfections, cells and supernatants were collected. Molecular analysis RNA was extracted both from supernatants from the experiment and from propagations of individual plaques, reverse transcribed into cDNA and analysed via two parallel real time PCR reactions allowing discrimination between CW1 and Wu20 at both genomic extremities (regions 1 and 5, located at the ORF1 and ORF3 terminal respectively), as previously described by Mathijs et al., 2010. For analysis of the supernatants, quantifications were also performed via real time PCR. Accordingly, amplicons corresponding to region 1 were amplified for both CW1 and Wu20, then cloned and in vitro transcribed to provide a standard curve for RNA copies. Following this, values for genomic copies were deduced and results were normalised with GAPDH gene transcripts. Isolation and screening of progeny viruses A plaque assay for virus isolation from the co- or superinfection experiments was set up by modifying the protocol described by Hyde et al. (2009). Thus, after 24 h of incubation, 36 plaques were randomly picked for each condition and propagated by inoculation onto RAW 264.7 cells. After this amplification step, monitoring of recombination events was performed by PCR and Real-Time PCR on extracted, reverse transcribed viral RNA, using two sets of primers to amplify regions 1 and 5. The use of two pairs of TaqMan probes allowed discrimination of the strains WU20 and CW1 in two different regions and identification of recombinant strains. Results: Molecular analysis The Real-Time PCR performed on supernatants collected at 24 h post infection showed a greater number of copies of MuNoV Wu20 cDNA in almost all conditions, except t 0 h, 0.5 h, 1 h, 2 h at the MOI 10, where an increase in the number of copies of the CW1 strain was noted. In particular, the latter showed a peak at 1 h at the MOI 10 (89%) followed by a rapid reduction in later times (t 8 h: 20%). Interestingly, for both viruses expected ratios were never attained during the study with the notable exception of the MOI ratio 0.1/1 and the condition t1 MOI 10/1. Isolation and screening of progeny viruses Molecular analysis conducted on plaques selected in the condition of coinfection at MOI 1 and 10 highlighted a predominance of the strain MuNoV CW1 (90%) from t 0h to t 2h, followed by a sharp reduction from t 4h leading to complete absence at t 24h. The Wu20 strain showed a progressive increase from 4h (10%) to 24h (100%). Overall, the occurrence of recombination events was very rare. Only three putative recombination events were detected at t1 h MOI 1/1 and t 4 h MOI 1/1. Conclusion: The profiles of viral ratios over time are highly interesting. Particularly the infection with CW1 at the MOI 10, with a relative percentage of genomic quantifications of about 50% at the two first time points is intriguing. While the percentage is changed completely at t1 MOI 1 to give the expected ratio of 90/10, it then gradually decreases over the next time points to less than 10% at 24 h post infection. The presence of numerous recombinant viruses as a possible explanation for the t1 MOI 1 peak seems unlikely, as very few putative recombinants were detected during the screening process. The single-step growth kinetics established by Mathijs et al in 2010, showing great similarities for both strains, indicate that the replicative cycle dynamics of the viruses are probably also not responsible. The decrease, especially marked after 8 h, is suggestive of a superinfection exclusion mechanism, where productive infection with Wu20 induces a resistance of the cells to infection with the homologous CW1. Alternatively, in view of the above-mentioned growth curve at high MOI, the decrease might also be due to the end of the first replication cycle having been reached, with no more viable cells left for infection. Considering the 50% viral ratio estimated by genomic copies for the early time-points, the identification of CW1 as the predominant strain (90%) after plaque purification for the same time appears to be somewhat of a discrepancy and merits further investigation Although circulating recombinant NoV strains seem to be common, in vitro recombination is a rare event, at least in the protocol described above, and does not seem to be easily influenced by parameter changes such as time of infection and MOI. Parameters where putative recombinations were identified include t1 MOI 1 and t4 MOI 1. The possible recombinants are yet to be confirmed by sequencing reactions. Further study is necessary to understand mechanisms favouring the predominance of replication of recombinant virus strain in vivo and the challenges of such a replication in vitro. The occurrence of recombination was theoretically limited to one cycle of replication by the protocol (MOI 1 of Wu20). More than one replication cycle might be necessary to enhance the process of recombination by increasing the number of replicating events that could favour recombination. Thus, initial infection at a lower MOI might be an interesting future consideration. Other mechanisms than a time-dependent coinfection might also be worth exploring. Acknowledgements: We thank Professor Herbert Virgin and Dr Larissa Thackray (Washington University, St Louis, MO, USA) for providing the MNV isolates and RAW 264.7 cells. [less ▲]

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See detailComparison of individuals’ susceptibility to false memory induced by both DRM and misinformation paradigms involving emotional material
Martial, Charlotte ULg; Dehon, Hedwige ULg

Poster (2015, September)

False memories induced by the DRM procedure (“Deese, Roediger and McDermott”; Deese, 1959; Roediger & McDermott, 1995) or the misinformation procedure (in which a person’s recollection of a witnessed ... [more ▼]

False memories induced by the DRM procedure (“Deese, Roediger and McDermott”; Deese, 1959; Roediger & McDermott, 1995) or the misinformation procedure (in which a person’s recollection of a witnessed event is altered after exposure to misinformation about this event; Loftus et al., 1978) are due to errors in source monitoring processes (e.g., Johnson et al., 1993) and one might expect the correlation between these false memories quite positive. However, the few laboratory studies comparing the DRM paradigm and the misinformation paradigm show small (Zhu et al., 2013) or no correlation (Ost et al., 2013) between the false memories elicited by these procedures. However, these studies vary in terms of methodological details. For instance, false memories from the misinformation procedure involved emotional content while those from the DRM procedure only included neutral materials. This study investigated the relationship between false memories induced by two different paradigms (a DRM task and a misinformation procedure) both involving an emotional material. Participants (N = 154) completed an emotional variant of the DRM (neutral, positive and negative lists) and the misinformation (neutral, positive and negative images) procedures and their performances on both tasks were compared. Although both paradigms reliably induced false memories in participants, our analyses revealed only a marginally weak positive correlation (r = .147, p = .051) between misinformation and DRM false memories using emotional variants. These results support the idea that DRM and misinformation false memories are underpinned by (at least in part) different mechanisms and that the previous mixed results were not due to the specific content of the DRM or the misinformation task used. [less ▲]

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See detailA logarithmic commensurability theorem for a class of GDIFSs
Leroy, Julien ULg

Poster (2015, September)

Detailed reference viewed: 2 (0 ULg)
See detailInvolvement of adamalysin proteases in modulations of tumor microenvironment and premetastatic niches.
Donati, Kim ULg; Bekaert, Sandrine; Sepult, Christelle ULg et al

Poster (2015, September)

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See detailSound production in piranhas and relatives: comparisons between species
Melotte, Geoffrey ULg; Michel, Christian ULg; Parmentier, Eric ULg

Poster (2015, September)

Acoustic communication plays an important role in the life of many teleost species where it is mainly involved in agonistic and/or courtship behavior. Despite the large number of Serrasalmidae species (92 ... [more ▼]

Acoustic communication plays an important role in the life of many teleost species where it is mainly involved in agonistic and/or courtship behavior. Despite the large number of Serrasalmidae species (92), sound production has been described only in the genera Serrasalmus and Pygocentrus. The aim of this study was first to investigate the sound producing abilities of different Serrasalmidae species and then to describe and understand the corresponding mechanisms. One herbivorous species, Piaractus brachypomus, produces sounds composed of a single pulse. The mechanism would involve the vibration of the bladder due to the hypaxial musculature contraction. In contrast, the calls emitted by Serrasalmus rhombeus, Serrasalmus compressus, Serrasalmus marginatus, Serrasalmus elongatus, Pygocentrus nattereri and Pristobrycon eigenmanni are all harmonic sounds composed of several pulses without inter-pulse interval. They all show the same kind of mechanism: the sound results from the forced vibration of the swimbladder following the contraction of sonic muscles that are attached to a perpendicular tendon surrounding ventrally the bladder. A last species, Pygopristis denticulata, is able to produce another type of sounds. It consists of several pulses with irregular pulse period and is likely produced by a sonic muscle inserting on the skull and on the rostral part of the swimbladder. The relatively high diversity of sound types and mechanisms in Serrasalmidae will be used in the future to understand the evolutionary development of this particular behavior. Do the mechanisms evolve separately or is there a continuity between them? [less ▲]

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See detailRegional occurence of greenhouses gases in groundwater: Initial results in shallow Belgian aquifers.
Hakoun, Vivien ULg; Gesels, Julie ULg; Tseng, Jean Hsiao-Chun et al

Poster (2015, September)

Currently, the lack of robust, context-distributed subsurface greenhouses gases (GHG) concentrations data is a key bottleneck to reduce the uncertainty range of GHG groundwater input to continental ... [more ▼]

Currently, the lack of robust, context-distributed subsurface greenhouses gases (GHG) concentrations data is a key bottleneck to reduce the uncertainty range of GHG groundwater input to continental surface water bodies such as rivers or lakes estimates. Carbon dioxyde (CO2), methane (CH4) and nitrous oxyde (N2O) are likely to be indirectly transferred to the atmosphere through groundwater discharge into continental surface water bodies. We aim to extend regional-scale estimates of indirect GHG emissions by screening, in numerous hydrogeological (such as alluvial, sandstone, chalk and limestone aquifers) and land use contexts (such as industrial and agricultural), the occurence of these gases. Here, we report and discuss CO2, CH4 and N2O concentrations from an initial survey conducted over selected sites (n= 40) within shallow (0-100 m depth) aquifers in Wallonia (Belgium) for the first time. The preliminary results obtained in this study show that the range of GHG concentrations varies between 5160 and 47544 ppm, 0 and 1064 nmol.L-1, as well as 1 and 5637 nmol.L-1 for the partial pressure of CO2, CH4 and N2O respectively. This new and unique regional dataset provides a first step in developping a refined understanding of favorable contexts for GHG occurence in groundwater which may be used to reduce the uncertainties related to indirect emissions of GHG through groundwater-surface water transfers. [less ▲]

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See detailBaseline data on the cyanobacterial diversity of Svalbard assessed by pyrosequencing
Laughinghouse IV, Haywood Dail; Stelmach Pessi, Igor ULg; Velázquez, David et al

Poster (2015, September)

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See detailTailoring γ-Al2O3 supports with specific silicon precursors
Claude, Vincent ULg; Vilaseca, Miriam; Lambert, Stéphanie ULg

Poster (2015, September)

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See detailOverview of the ground facilities for controlling the OUFTI-1 nanosatellite and for routing its radio-communications through the worldwide D-STAR repeater network
Werner, Xavier ULg; De Dijcker, Sébastien ULg; Broun, Valery ULg et al

Poster (2015, September)

Overview of the current state and upgrade plan of the OUFTI-1 nanosatellite ground segment. The OUFTI-1 project was initiated in September 2007. The OUFTI-1 nanosatellite is a one-unit (1U) CubeSat. Its ... [more ▼]

Overview of the current state and upgrade plan of the OUFTI-1 nanosatellite ground segment. The OUFTI-1 project was initiated in September 2007. The OUFTI-1 nanosatellite is a one-unit (1U) CubeSat. Its main payload is - in essence - a D-STAR repeater in space, potentially the first one ever. D-STAR is an amateur-radio (“ham”), digital radio-communication protocol (with associated equipment) allowing the simultaneous transmission of voice and data, such as GPS coordinates and call-signs. The satellite was tested in 2014 and 2015 within the ESA’s Education Office Fly Your Satellite! (FYS) project, and it is now fully qualified and ready for launch and operation in space. [less ▲]

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See detailArchitecture of educational OUFTI-1 nanosatellite of University of Liège, as tested in preparation for space flight
Werner, Xavier ULg; De Dijcker, Sébastien ULg; Broun, Valery ULg et al

Poster (2015, September)

Overview of the OUFTI-1 nanosatellite space segment. The OUFTI-1 project was initiated in September 2007. The nanosatellite is a one-unit (1U) CubeSat. Its main payload is - in essence - a D-STAR repeater ... [more ▼]

Overview of the OUFTI-1 nanosatellite space segment. The OUFTI-1 project was initiated in September 2007. The nanosatellite is a one-unit (1U) CubeSat. Its main payload is - in essence - a D-STAR repeater in space, potentially the first one ever. D-STAR is an amateur-radio (“ham”), digital radio communication - protocol (with associated equipment) allowing the simultaneous transmission of voice and data, such as GPS coordinates and call-signs. [less ▲]

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Peer Reviewed
See detailAnalysis of the time-dependent electrical current in reverse-biased p-GeSn/n-Ge mesa diodes
Baert, Bruno ULg; Gupta, Somya; Gencarelli, Federica et al

Poster (2015, September)

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See detailMagnesium-doped Cuprous Oxide (Mg:Cu2O) thin films as a transparent p-type semiconductor oxide
Avelas Resende, João ULg; Nguyen, Ngoc Duy ULg; Deschanvres, Jean-Luc et al

Poster (2015, September)

Oxide electronics is an important emerging area, notably for the development of transparent thin film transistors (TFTs) and other complex electronic circuits. The successful application of n-type oxides ... [more ▼]

Oxide electronics is an important emerging area, notably for the development of transparent thin film transistors (TFTs) and other complex electronic circuits. The successful application of n-type oxides to TFTs has motivated the interest in p-type oxide based semiconductors, also to be applied to TFTs or to complementary metal-oxide semiconductor (CMOS) technology. However, until now there is a lack of p-type oxide semiconductors with performance similar to that of n-type oxide. Among the different metallic oxides, Cu (I)-based oxides exhibit one of the lowest ionic character. These compounds are therefore one of the most promising candidates as p-type transparent semiconductors.Nevertheless, the band gap of 2,17eV is modest for transparent electronics applications, since the transmittance of Cu2O films is low on the visible part of the light spectrum. The incorporation of cations with large radii than Cu has been proposed as a way to achieve a higher band gap, by diminishing of three-dimensional Cu-Cu interactions, only possible with larger cations than Cu+. Therefore, cation doped Cu2O thin films were grown by metal-organic chemical vapor deposition (MOCVD). The three doping elements studied (Sr2+, Sn2+ and La3+) were selected having in account theoretical predictions for the band structure and the deposition conditions of Cu2O. The study focus on thin films growth optimization combined with electronic transport analysis and optical transmittance measurements. [less ▲]

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See detailInfluence of soft ferromagnetic materials on the magnetic flux density above large grain, bulk high temperature (RE)BCO superconductors: measurements and modelling
Philippe, Matthieu ULg; Ainslie, Mark D; Fagnard, Jean-François ULg et al

Poster (2015, September)

Due to their ability to trap high magnetic fields, bulk (RE)BCO superconductors can be used as powerful permanent magnets in various engineering applications such as rotating machines and magnetic ... [more ▼]

Due to their ability to trap high magnetic fields, bulk (RE)BCO superconductors can be used as powerful permanent magnets in various engineering applications such as rotating machines and magnetic bearings. We combine soft ferromagnetic pieces with bulk, large grain (RE)BCO high temperature superconductors to form superconductor/ferromagnet (SC/FM) hybrid structures. We study how the ferromagnetic pieces influence (i) the profile shape of the trapped magnetic flux density at the surface of each structure and (ii) the decrease of the trapped field under an applied field that is orthogonal to the main magnetization (crossed field configuration). Hall probe mappings of the trapped magnetic flux density profile above the hybrid structures at 77 K are compared to modelled profiles using a 2D finite element method. Modelling results are in excellent qualitative and quantitative agreement with the measurements. The model is then used to study the magnetic flux distribution and predict the behaviour for other constitutive laws and ferromagnet geometries. For the modelled configurations, the magnetic flux density is enhanced on the face opposite to the ferromagnet. Both thickness and saturation magnetization of the ferromagnetic material are found to be important parameters. The saturation regime of the ferromagnet can be predicted using a simple analytical model. We show that thin ferromagnetic discs can be driven to full saturation even though the superconductor magnetic field is much smaller than their saturation magnetization. Remarkably, the beneficial influence of the ferromagnet on the trapped field can be observed even if the trapped flux density above the superconductor is much larger than the ferromagnet saturation magnetization. Finally, we show that the ferromagnetic material acts as a magnetic shield and lowers the relative demagnetization effect caused by the application of transverse (crossed) magnetic field cycles. [less ▲]

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See detailSurface aeration in baffled stirred tanks: hydrodynamics, mixing and mass transfer characteristics
de Lamotte, Anne ULg; Delafosse, Angélique ULg; Calvo, Sébastien ULg et al

Poster (2015, September)

Biotechnological and chemical processes often need a supply of gas for acceptable product formation. In some applications - where either gas requirements/reactor volumes are relatively low, or bubbles are ... [more ▼]

Biotechnological and chemical processes often need a supply of gas for acceptable product formation. In some applications - where either gas requirements/reactor volumes are relatively low, or bubbles are undesirable - aeration through the liquid free-surface is enough to meet the demand. In case of sparged stirred tanks, aeration through the liquid free-surface is a factor to be determined when scaling-up /down processes. Gas-liquid transfer is strongly influenced by the hydrodynamic conditions. Two phenomena, occurring at different scales, can be coupled in order to explain mass transfer : (i) circulation (macroscale) and (ii) mixing/homogenization (microscale). Mixing/homogenization takes into consideration the small eddies responsible for the rippled liquid free-surface and for the concentration gradients surrounding it. Circulation determines the fluid path across the reactor as well as its contribution of the surface aeration and leads to periodic and local deformation of the liquid free-surface. Circulation also accounts for the design of the reactor, where the scaling problems are focused. The objective of this work is to develop an experimental approach able to fully (global and local quantities) characterize a chosen agitation configuration in terms of hydrodynamics, mixing and transfer, in order to assess the capability of computational methods to predict gas-liquid mass transfer due to aeration through the liquid free-surface. [less ▲]

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See detailBehavioral effects of exposure to salinity on tadpoles of two syntopic species of spadefoot toads (genus Pelobates)
Székely, Diana ULg; Stanescu, Floriana; Székely, Paul et al

Poster (2015, September)

Detailed reference viewed: 10 (0 ULg)
See detailA next-generation protocol for the assessment of cyanobacterial diversity
Stelmach Pessi, Igor ULg; de Carvalho Maalouf, Pedro; Laughinghouse IV, Haywood Dail et al

Poster (2015, September)

Detailed reference viewed: 14 (4 ULg)
See detailDeciphering the molecular mechanisms underlying NLRP3 inflammasome activation by saturated fatty acids
Gianfrancesco, Marco ULg; Bloch, Katarzyna; Dehairs, Jonas et al

Poster (2015, September)

Detailed reference viewed: 26 (12 ULg)
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See detailMaximal fidelity between symmetric multiqubit states and entanglement classes
Neven, Antoine ULg; Mathonet, Pierre ULg; Gühne, Otfried et al

Poster (2015, September)

We present the results of our research concerning a conjecture about the maximal fidelity between a symmetric (permutation invariant) multiqubit state and the states belonging to a given entanglement ... [more ▼]

We present the results of our research concerning a conjecture about the maximal fidelity between a symmetric (permutation invariant) multiqubit state and the states belonging to a given entanglement class. [less ▲]

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See detailDetermination of air‐sea ice transfer coefficient for CO2: Significant contribution of gas bubble transport during sea ice growth
Kotovitch, Marie ULg; Moreau, S.; Zhou, Jiayun et al

Poster (2015, September)

Air‐ice CO2 fluxes were measured continuously from the freezing of a young sea‐ice cover until its decay. Cooling seawater was as a sink for atmospheric CO2 but asthe ice crystalsformed,sea ice shifted to ... [more ▼]

Air‐ice CO2 fluxes were measured continuously from the freezing of a young sea‐ice cover until its decay. Cooling seawater was as a sink for atmospheric CO2 but asthe ice crystalsformed,sea ice shifted to a source releasing CO2 to the atmosphere throughout the whole ice growth. Atmospheric warming initiated the decay, re‐shifting sea‐ice to a CO2 sink. Combining these CO2 fluxes with the partial pressure of CO2 within sea ice, we determined gas transfer coefficients for CO2 at air‐ice interface for growth and decay. We hypothesize that this difference originates from the transport of gas bubbles during ice growth, while only diffusion occurs during ice melt. In parallel, we used a 1D biogeochemical model to mimic the observed CO2 fluxes. The formation of gas bubbles was crucial to reproduce fluxes during ice growth where gas bubbles may account for up to 92 % of the upward CO2 fluxes. [less ▲]

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See detailMT4-MMP, a potential therapeutic target in triple negative breast cancer
Yip, Cassandre ULg; FOIDART, Pierre ULg; SOMJA, Joan ULg et al

Poster (2015, September)

MT4-MMP and EGFR axis may have a significant role in patient outcome and response to EGFR targeted therapy. This axis is clinically relevant in TNBC, the most aggressive breast cancer subtype. TNBC are ... [more ▼]

MT4-MMP and EGFR axis may have a significant role in patient outcome and response to EGFR targeted therapy. This axis is clinically relevant in TNBC, the most aggressive breast cancer subtype. TNBC are known to express high level of EGFR and treatment options are limited due to the non response of to the EGFR targeted therapy. Expression levels of MT4-MMP and EGFR in TNBC may be used as prognosis factor for the selection of patient who may respond or not to EGFR targeted therapy. Also, our data shed light and the potential therapeutic option of targeting both MT4-MMP and EGFR in TNBC. [less ▲]

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See detailCell-based description of ventricular contraction in a model of the human cardiovascular system
Kosta, Sarah ULg; Negroni, Jorge; Lascano, Elena et al

Poster (2015, August 31)

Detailed reference viewed: 22 (8 ULg)
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See detailExploring the schizophrenic hyperreflexivity on the Rorschach test
Englebert, Jérôme ULg; Bataille, Jennifer; Mormont, Christian ULg et al

Poster (2015, August 28)

L’hyper-réflexivité schizophrénique peut être définie comme une attitude particulière de la conscience consistant à interroger de façon explicite et réflexive des phénomènes généralement implicites et ... [more ▼]

L’hyper-réflexivité schizophrénique peut être définie comme une attitude particulière de la conscience consistant à interroger de façon explicite et réflexive des phénomènes généralement implicites et préréflexifs (Sass, 2014). Notre hypothèse est que ce mécanisme se manifeste dans les protocoles du test de Rorschach des sujets schizophrènes (Englebert, 2013). Pour l’éprouver, nous avons administré le test à douze sujets schizophrènes. L’originalité de cette recherche repose sur une seconde présentation des planches (trois jours plus tard) qui a permis d’évoquer avec les sujets la permanence de leurs perceptions et de discuter de l’acception commune de celles-ci (pensez-vous que la plupart des autres personnes pourrait voir ce que vous voyez ?). Les résultats confirment notre hypothèse, tant au niveau quantitatif (les marqueurs de l’hyper-réflexivité que nous avions identifiés se retrouvent dans la majorité des protocoles) que qualitatif (phrases suggérant une interrogation épistémologique du test, par exemple). Enfin, nous remarquerons que l’attitude schizophrénique envers le test de Rorschach est assez subtile puisqu’elle identifie le fondement épistémologique du test reposant sur la nécessité d’une fausse perception – une « violation de la réalité » selon Exner (2003). Les sujets schizophrènes mettent en évidence la règle implicite sur laquelle repose le test qui consiste à ne pas donner la seule véritable bonne réponse (systématique) au test qui est « une tache ». [less ▲]

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See detailWhy are flux avalanches deflected by a metallic layer?
Brisbois, Jérémy ULg

Poster (2015, August 27)

Sudden avalanches of magnetic flux bursting into a superconducting sample are deflected from their trajectories when encountering a conductive layer deposited on top of the superconductor. Remarkably, in ... [more ▼]

Sudden avalanches of magnetic flux bursting into a superconducting sample are deflected from their trajectories when encountering a conductive layer deposited on top of the superconductor. Remarkably, in some cases the flux is totally excluded from the area covered by the conductive layer. Even if experimental evidence of the phenomenon has been available for a few years, there is currently no theoretical model to describe it. Moreover, the question whether a single vortex would also undergo deflection when entering the region covered by a metallic layer is still unanswered. In this work we use the magneto-optical imaging (MOI) technique, based on the Faraday effect, to show that a conductive layer (Cu) can repel flux avalanches triggered in an underlying superconducting film (Nb) (see figure above). We present a simple classical model that accounts for the deflection of a single vortex and considers a magnetic monopole approaching a semi-infinite conductive plane. This model suggests that electromagnetic braking, arising from the eddy currents induced in the metal due to the moving vortex, is an important mechanism responsible for avalanche deflection. Furthermore, we have found that early theoretical descriptions for the vortex damping enhancement due to the metallic sheet need a correction at large vortex velocities, where a decrease of the damping coefficient is expected. [less ▲]

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See detailNegative Relative Clauses in Late Egyptian. A Functional Perspective
Sojic, Nathalie ULg

Poster (2015, August 26)

The poster contains a functional taxonomy of the negative relative clauses in Late Egyptian

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See detail"Reden und Rufe": are they kingly patterns?
Motte, Aurore ULg

Poster (2015, August 26)

Les discours des travailleurs, ou « Reden und Rufe », sont principalement connus grâce aux travaux d’Erman et Guglielmi [1]. Malgré quelques faiblesses, ceux-ci sont toujours les seuls ouvrages de ... [more ▼]

Les discours des travailleurs, ou « Reden und Rufe », sont principalement connus grâce aux travaux d’Erman et Guglielmi [1]. Malgré quelques faiblesses, ceux-ci sont toujours les seuls ouvrages de référence disponibles. Ce travail ambitionne de s’intéresser aux origines des discours des travailleurs. Quand, où, comment, pourquoi émergent-ils ? Autant de questions laissées jusqu’ici sans réponses. Après une brève remise en contexte des « Reden und Rufe », il sera montré que les discours des travailleurs sont une partie intégrante du « nouveau » programme décoratif royal, dont l’apothéose est atteinte sous Sahourê. Ce papier présentera également les premières réceptions de ces discours dans les tombes privées et leur évolution au sein de l’élite (mise en évidence de traditions phraséologiques, d’adaptation et d’innovation). Il sera montré que les discours des travailleurs s’inscrivent dans la tradition égyptienne de l’élite, qui reprend à son compte des motifs d’origine royale pour établir son propre programme décoratif. [1] A. ERMAN (1919), Reden, Rufe und Lieder auf Gräberbildern des Alten Reiches, Berlin (APAW philos.-hist. Kl., Abh. 15). W. GUGLIELMI (1973), Reden, Rufe und Lieder auf altägyptischen Darstellungen der Landwirtschaft, Viehzucht, des Fisch- und Vogelfangs vom Mittleren Reich bis zur Spätzeit, Bonn, Habelt (TÄB 1). [less ▲]

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See detailCharacterization of talcschist's weathering Materials in Henguegue (Cameroon)
Woguia, Damaris Laure ULg; Ngo Bidjeck, Louise Marie

Poster (2015, August 25)

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See detailThe ‘Landscape’ of Nuclear Safeguards: a Comparative Analysis of the International and Regional Systems
Colussi, Ilaria Anna ULg

Poster (2015, August 24)

Nuclear proliferation poses a severe threat to the international community, and the role of the law in this area is crucial. The notion of ‘nuclear non-proliferation’ is twofold: (a)disarm or vertical non ... [more ▼]

Nuclear proliferation poses a severe threat to the international community, and the role of the law in this area is crucial. The notion of ‘nuclear non-proliferation’ is twofold: (a)disarm or vertical non-proliferation: measures for reduction of the number of existing arsenals; (b)horizontal non-proliferation: containment of the number of States and no State entities that do not have but are acquiring nuclear weapons, or developing the capability and materials for producing them. Different sources of the law exist at the international and regional level for addressing the issue. For the implementation of the principles and obligations embedded in the agreements, it is essential to set up a verification and safeguards system. Safeguards provisions are established at the international and regional level. Thus, the aim of this study to analyse, critically and comparatively, the different safeguards systems that have been legally adopted at the international and regional level so far. [less ▲]

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See detailStudy of Developmental and Molecular Processes Regulated by Sorbs1 using a Combination of in vitro and in vivo models Alexandra Veloso1, Anouk Bleuart1, Maud Martin1, Jonathan Bruyr1, Marie-Ange Mavaccarella1, and Franck Dequiedt1
Bacquelaine Veloso, Alexandra ULg; Dequiedt, Franck ULg

Poster (2015, August 24)

SoHo proteins belong to a family that includes three members: Sorbs1 (Cbl associated protein CAP/ponsin), Sorbs2 (Arg-Binding Protein 2, ArgBP2) and Sorbs3 (Vinexin). These proteins share a similar ... [more ▼]

SoHo proteins belong to a family that includes three members: Sorbs1 (Cbl associated protein CAP/ponsin), Sorbs2 (Arg-Binding Protein 2, ArgBP2) and Sorbs3 (Vinexin). These proteins share a similar structure with a SoHo domain in N-terminal region and three SH3 domains in carboxy terminal region. These characteristic domains bind to several signaling molecules involved in a variety of cytoskeleton-related processes, and SoHo family members are thus thought to function as adaptor proteins. However, the precise role of these proteins in the cytoskeleton regulation and associated biological functions remains unknown. It is well established that cytoskeleton regulation is critical for various developmental events including angiogenesis, the process by which new blood vessels develop from pre-existing ones, and myogenesis, the process responsible for muscle formation and regeneration. The goal of this project is to identify the developmental function of Sorbs1 and characterize the underlying molecular events by exploiting a combination of in vivo (Zebrafish) and in vitro models. Phenotype analysis revealed that Morpholino-mediated knock-down of Sorbs1 induces abnormal development of cardiac, angiogenic and muscles structures. Knock-down zebrafish embryos were unable to form cardiac looping and present a cardiac edema. Also, it was noticed that tail morphology was altered by Sorbs1 knock-down suggesting that Sorbs1 plays a role in trunk muscle formation. Finally, the development of venous angiogenic structures, such as caudal vein plexus (CVP) and subintestinal veins (SIV), was specifically affected by Sorbs1inactivation. Interestingly, Sorbs1 seems to have a specific role in venous angiogenesis (CVP and SIV), since arterial angiogenic structures, such as Intersegmental vessels, were not affected in Sorbs1 morphants. In conclusion, these preliminary results of our work highlighted important developmental defects by consequence of Sorbs1 inactivation in Zebrafish. Some of these defects appear to be regulated by angiogenesis and myogenesis, two developmental processes for which the therapeutic implications are undeniable. [less ▲]

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See detailDoes elevation in atmospheric CO2 concentration impact aphid alarm signaling?
Boullis, Antoine ULg; Appeldoorn, Claire; Oostrom, Marjolein et al

Poster (2015, August 24)

The effect of global atmospheric changes on interactions between vegetation and phytophagous insects is well studied since several years, but how does these changes affect the interactions between ... [more ▼]

The effect of global atmospheric changes on interactions between vegetation and phytophagous insects is well studied since several years, but how does these changes affect the interactions between herbivore insects and their natural enemies is less clear. Impact of an increase in CO2 concentration on aphids is also well documented, but few publications focused on their chemical ecology. When endegered, aphids emit an alarm pheromone (generally composed of only one molecule: (E)-Beta-Farnesene) to induce an escape behavior in the colony. Here, we studied how an increase in CO2 concentration affects the alarm signaling mechanisms of the aphid Acyrthosiphon pisum, focusing on the production, the emission (under attack) and the perception of this signal. [less ▲]

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See detailBacterial community composition in three freshwater reservoirs of di erent alkalinity and trophic status
Llirós, Marc; Inceoglu, Ozgul; Garcia-Armisen, Tamara et al

Poster (2015, August 23)

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See detailThe study of air-ice CO2 exchange emphasize the importance of gas bubble transport during sea ice growth
Kotovitch, Marie ULg; Moreau, Sébastien; Zhou, Jiayun et al

Poster (2015, August 20)

We report air-ice CO2 fluxes measured continuously using automated chambers over artificial sea ice from freezing to decay. We observed an uptake of CO2 as seawater was cooling down prior to sea ice ... [more ▼]

We report air-ice CO2 fluxes measured continuously using automated chambers over artificial sea ice from freezing to decay. We observed an uptake of CO2 as seawater was cooling down prior to sea ice formation. As soon as the first ice crystals started to form, we observed a shift from a sink to a source. Sea ice released CO2 until we initiated the ice decay by warming the atmosphere. Sea ice then returned to be a CO2 sink. Direct measurements of the fluxes were consistent with the depletion of dissolved inorganic carbon in sea ice. Measurements of bulk partial pressure of CO2 in sea ice and of atmospheric CO2 allowed us to assess a gas exchange coefficient for CO2 at the air-sea ice interface during the grow stage. We compared these observations with a 1D biogeochemical model. Discrepancies between the model and the observations lead us to emphasize the role of gas bubbles in CO2 transport through sea ice. [less ▲]

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See detailTwo differentiation trends and parent magmas at Calbuco volcano (CSVZ, Chille)
Montalbano, Salvatrice ULg; Schiano, Pierre; Cluzel, Nicolas et al

Poster (2015, August 19)

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See detailDepression in Women and in Men: Differences on Behavioral Avoidance and on Behavioral Activation
Wagener, Aurélie ULg; Baeyens, Céline; Blairy, Sylvie ULg

Poster (2015, August 06)

Depression is a well-known disorder characterized by e.g. sadness, loss of interest and pleasure, feelings of guilt or worthlessness. Depression is also characterized by a decrease of the level of ... [more ▼]

Depression is a well-known disorder characterized by e.g. sadness, loss of interest and pleasure, feelings of guilt or worthlessness. Depression is also characterized by a decrease of the level of engagement in activities also conceptualized as behavioral avoidance. Indeed, depressed patients less and less engage themselves in pleasurable activities (e.g. they spend more and more time in their bed, see their friends more rarely). Reciprocally, this decrease of the level of engagement in activities reinforces and maintains depressive symptoms. This relationship between depression and a low level of engagement in activities is well-established in the scientific literature but no study has, until now, discussed the reasons of this decrease of engagement in activities. According to theoretical models of depression (Beck, 2008; Lewinsohn, 1985; Watkins, 2009), five sets of psychological processes (PP) are involved in depressive symptomatology: negative repetitive thoughts, maladaptive emotion regulation strategies, low environmental rewards, negative self-image and inhibition. We hypothesize that these PP could be considered as explaining factors of the behavioral avoidance. Furthermore, we hypothesize that other PP could be considered as explaining factors of the behavioral activation (adaptive emotion regulation strategies, high environmental rewards, positive self-image, approach and high self-clarity). Then, our aim is to assess the links between behavioral avoidance as well as activation and the PP mentioned above. In order to reach this objective, we developed a model of these links based on the psychological model of mental ill-health of Kinderman (2005, 2013). According to this model, biological, social and circumstantial factors lead to mental disorders through their conjoint effects on psychological processes. Furthermore, because depression is different in women and in men, we assessed the adequacy of our model according to the sex. Clinical and community adults completed an online survey assessing the psychological processes mentioned above, avoidance and activation. Since several questionnaires were used to assess each PP, factorial scores were computed for each one. Preliminary analyses (confirmatory factor analyses) were realized with a sample of 393 women and 139 men. The results revealed differences between men and women. For women, on the one hand, low levels of environmental rewards, maladaptive emotion regulation strategies and negative repetitive thoughts are linked to behavioral avoidance, and on the other hand, high levels of environmental rewards and positive self-image are linked to behavioral activation. For men, on the one hand, negative self-image, maladaptive emotion regulation strategies and low environmental rewards are linked to behavioral avoidance, and, on the other hand, high levels of environmental rewards and positive self-image are linked to behavioral activation. The final results will be presented during the convention, as data-collection is on-going and will end in May 2015. Clinical implications of these results will also be discussed such as the relevance of working on the levels of environmental rewards. [less ▲]

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See detailAlternatives to traditional valorisation ways for brewer’s spent grains
Villani, Nicolas ULg; Aguedo, Mario ULg; Richel, Aurore ULg

Poster (2015, August 05)

Brewer’s Spent Grains (BSG) are a highly available and cheap food supply chain waste (FSCW) that is mainly used in low-valued feed applications. This residue represents around 85 % of the total amount of ... [more ▼]

Brewer’s Spent Grains (BSG) are a highly available and cheap food supply chain waste (FSCW) that is mainly used in low-valued feed applications. This residue represents around 85 % of the total amount of waste produced by breweries with an annual tonnage of 3.4 million tons (on a dry basis) in the European Union. Based on its composition, BSG could be valorised in a wide variety of value-added products. For example, cellulose and remaining starch could easily be turned into ethanol or used as solid state fermentation media or as platform molecules for further chemical synthesis. These alternative valorisation ways could lead to an important economic relief through the whole brewery industry. Herein is described a multistep fractionation of BSG into cellulosic pulp, free sugars, proteins, germs and lignin using an Organosolv acidic pretreatment. This extraction procedure has been optimised in order to allow the most efficient and complete valorisation of BSG. [less ▲]

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See detailEvidence of a fine-scale genetic structure for the endangered Pyrenean desman (Galemys pyrenaicus) in the French Pyrenees
Gillet, François ULg; Cabria Garrido, Maria Teresa; Blanc, Frédéric et al

Poster (2015, August 05)

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See detailDevelopment of cryopreservation methods for long-term preservation of cyanobacterial strains in the BCCM/ULC collection
Crahay, Charlotte ULg; Renard, Marine ULg; Mari, Maud et al

Poster (2015, August 03)

Long-term genetic and functional stability is a fundamental requirement for the maintenance of microorganisms and cryopreservation is the preferred method for the long-term storage of many micro-organisms ... [more ▼]

Long-term genetic and functional stability is a fundamental requirement for the maintenance of microorganisms and cryopreservation is the preferred method for the long-term storage of many micro-organisms, including cyanobacteria. The BCCM/ULC collection currently holds 200 cyanobacterial strains, but only 62 are cryo-preserved. The main limiting factors are the low levels of survival of some strains and the long periods required to recover from cryopreservation, and thus the inability to deliver rapidly cryopreserved strains to the user community. The devel-opment of improved cryopreservation protocols is therefore required for the future expansion and valorization of the collection. The BRAIN-be project PRESPHOTO (preservation of photosynthetic micro-algae in the BCCM collections) (www.presphoto.ulg.ac.be) aims to improve the preservation of cyanobacterial and diatoms in the BCCM/ULC and BCCM/DCG collections, respectively. [less ▲]

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See detailContribution of cyanobacteria to the building of travertines in a calcareous stream
Wilmotte, Annick ULg; Golubic, Stjepko; Kleinteich, Julia et al

Poster (2015, August 03)

The ambient temperature travertine deposits of the calcareous Hoyoux River (Modave, Belgium) and several tributaries are organized and promoted by the filamentous cyanobacterium identified by its ... [more ▼]

The ambient temperature travertine deposits of the calcareous Hoyoux River (Modave, Belgium) and several tributaries are organized and promoted by the filamentous cyanobacterium identified by its morphotype and ecological properties as Phormidium cf. incrustatum. A combination of techniques was used to study this biotope: physico-chemical parameters and CO2 measurements, Scanning and Transmission Electron Microscopy, RAMAN microspectroscopy. A molecular diversity study with pyrosequencing of the cyanobacterial 16S rRNA is in progress. A potential candidate was isolated in culture. [less ▲]

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See detailA next-generation approach to assess the cyanobacterial diversity and biogeography in the High Arctic (Svalbard)
Laughinghouse, Haywood Dail; Stelmach Pessi, Igor ULg; Velazquez, David et al

Poster (2015, August 03)

Polar ecosystems are extremely sensitive to global climate changes and human activities. Cyanobacteria are key photosynthetic organisms in these latitudes, due to their roles in soil aggregation, nitrogen ... [more ▼]

Polar ecosystems are extremely sensitive to global climate changes and human activities. Cyanobacteria are key photosynthetic organisms in these latitudes, due to their roles in soil aggregation, nitrogen fixation, carbon cycles, and secondary metabolite production, among others. Previous works indicate that different cyanobacterial taxa/communities have different impacts on the environment, in both biogeochemical cycles and bioactive compound productions. Furthermore, the presence of biogeographical patterns in microorganisms, as found in macroorganisms, is an ongoing debate. In this study, during the 2013 MicroFun expedition, we sampled 72 locations around Svalbard including diverse biotopes such as glacial forefields, tundra soils, hot springs, soil crusts, microbial mats, wet walls, cryoconites, plankton and periphyton, in order to (1) assess the biodiversity of cyanobacteria around Svalbard, (2) verify the existence of biogeographical trends around the archipelago, and (3) compare these data with other polar (cold) areas, especially Antarctica. We used a pyrosequencing approach targeting cyanobacteria-specific 16S rRNA gene sequences to deeply study the cyanobacterial communities. [less ▲]

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See detailThe BCCM/ULC collection : a Biological Ressource Center for polar cyanobacteria
Wilmotte, Annick ULg; Renard, Marine ULg; Lara, Yannick ULg et al

Poster (2015, August 03)

In this study, during the 2013 MicroFun expedition, we sampled 72 locations around Svalbard including diverse biotopes such as glacial forefields, tundra soils, hot springs, soil crusts, microbial mats ... [more ▼]

In this study, during the 2013 MicroFun expedition, we sampled 72 locations around Svalbard including diverse biotopes such as glacial forefields, tundra soils, hot springs, soil crusts, microbial mats, wet walls, cryoconites, plankton and periphyton, in order to (1) assess the biodiversity of cyanobacteria around Svalbard, (2) verify the existence of biogeographical trends around the archipelago, and (3) compare these data with other polar (cold) areas, especially Antarctica. We used a pyrosequencing approach targeting cyanobacteria-specific 16S rRNA gene sequences to deeply study the cyanobacterial communities. [less ▲]

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See detailGenome sequencing of an endemic filamentous Antarctic cyanobacterium
Lara, Yannick ULg; Verlaine, Olivier ULg; Kleinteich, Julia et al

Poster (2015, August 03)

The strain Phormidium priestleyi ULC007 was isolated from a benthic mat located in a shallow freshwater pond in the Larsemann Hills (69°S), Western Antarctica. This strain belongs to a cyanobacterial ... [more ▼]

The strain Phormidium priestleyi ULC007 was isolated from a benthic mat located in a shallow freshwater pond in the Larsemann Hills (69°S), Western Antarctica. This strain belongs to a cyanobacterial cluster that appeared as potentially endemic (Taton et al. 2006). After obtaining an axenic isolate, we sequenced the genome of this strain in the frame of the BELSPO CCAMBIO project, in order to better understand the functioning, metabolism and adaptative strategies of cyanobacteria to the extreme Antarctic environment. [less ▲]

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See detailIs the Mehler reaction the main photoprotective mechanism occurring in Symbiodinium in hospite?
Roberty, Stéphane ULg; Beraud, Eric; Ferrier-Pagès, Christine et al

Poster (2015, August)

The ecological success of reef-building corals throughout tropical oligotrophic waters relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium. This ... [more ▼]

The ecological success of reef-building corals throughout tropical oligotrophic waters relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium. This association allows the transfer of highly energetic compounds and an efficient recycling of growth-limiting nutrients. In the natural environment the holobiont have to cope with significant daily variations in light intensities that sometimes exceed Symbiodinium photosynthetic capacity. Fortunately, these organisms possess regulatory features that help to ensure that high light intensities can be endured without the accumulation of photodamage. Among them, it has been found recently that photoreduction of oxygen downstream PSI by the so-called Mehler reaction was the main alternative electron sink at the onset and steady state of photosynthesis in different cultured strains of Symbiodinium. In this study, we investigated the occurrence and the relative amplitude of this photoprotective mechanism in Symbiodinium cells living within the tropical coral Stylophora pistillata and the sea anemone Anemonia viridis. To this end, joint measurements of oxygen evolution, PSI and PSII activities were conducted. The impacts of CO2 limitation and CO2 fixation on the photoreduction of oxygen by PSI was also studied by using several inhibitors targeting the carbon concentrating mechanism and the Calvin-Benson-Bassham cycle. Conversely to cultured cells, these measurements revealed that the Symbiodinium located in S. pistillata, under control conditions, rely on other photoprotective mechanisms than the Mehler reaction to prevent over-excitation of the photosynthetic apparatus. However, we observed an increased O2 uptake capacity during photosynthesis when the efficiency of the carbon fixation was reduced in S. pistillata. [less ▲]

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See detailDo Triclosan affect hearing development of Cyprinodon variegatus larvae?
Schnitzler, Joseph ULg; Benichou, Farida; Pinte, Nicolas et al

Poster (2015, August)

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are ... [more ▼]

The aquatic environment represents the final sink for many chemicals, including bactericidal agents. Among them Triclosan (TCS) has been shown to affect the thyroid system of teleost. Larval stages are particularly vulnerable to deleterious effects of endocrine disrupters because of potential impairment of fish development and behaviour. Thyroid hormones are critical to the development of the brain and auditory system. Thus, TCS could affect the development of the brain and hearing. The aims of this study were: to investigate hearing development in sheepshead minnows (Cyprinodon variegatus) using the ABR technique (Auditory Brainstem Response) and to investigate the effects of triclosan on hearing development. Exposure to TCS was conducted from fertilization of eggs on at concentrations likely to be found in the environment: 20, 50 and 100 µgl-1. We characterized previously the ontogenic variation of thyroid hormones in embryos and larvae of sheepshead minnows. We observed an increase of thyroid hormones level around the 12th and the 15th day post hatching (dph), that may be associated with the transition from larval to juvenile stage during the development of this species. We concluded, that this period could be defined as a critical exposure window to pollutants. We determined hearing thresholds for sheepshead minnows of different ages. Our sheepshead minnows show ontogenic variations in the hearing ability during their development. At 30 days post hatching, their hearing ability is quite bad, with a narrow bandwidth of detected frequencies. But their hearing ability considerably enhance during their development to reach the adult hearing ability at around 80 days post hatching when this species reach sexual maturity. So we observe during the developmental phase of this fish species clear ontogenic improvements of the hearing ability and they showed an ontogenetic expansion in the frequency bandwidth they were able to detect. The effects of TCS in this development have yet to be determined but will be fully discussed. This study proposes an interesting new endpoint in thyroid disruption research. [less ▲]

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See detailThe hidden face of the human macrophage chitotriosidase: taking a new look at this enzyme based on the biochemical and phylogenomic analysis of its chitin binding domain
Crasson, Oscar ULg; Legrand, François; Léonard, Raphaël et al

Poster (2015, August)

Carbohydrates recognition is a critical process involved in numerous aspects of the cell biology such as inflammation, innate immune responses and proliferation. Chitin is an homopolysaccharide composed ... [more ▼]

Carbohydrates recognition is a critical process involved in numerous aspects of the cell biology such as inflammation, innate immune responses and proliferation. Chitin is an homopolysaccharide composed of β-1,4-linked N-acetylglucosamine (GlcNAc) units that is an abundant structural component of various infectious organisms like protozoans, nematodes and fungi. As there is no endogenous chitin produced by mammals, this polymer appeared to be a strategic target for innate immune agents which is why various carbohydrate binding proteins, associated or not with catalytic domains, are synthetized by plants and animals and are known to play a crucial role in innate immunity. The macrophage chitotriosidase (HCHT) is one of the three active chitinases synthetized by humans and has triggered significant attention recently due to its association with various inflammatory disorders. HCHT belongs to the Glycosyl Hydrolase family 18 (GH18) and is known to be involved in innate immunity. Nevertheless, its precise physiological function remains unclear. As numerous GHs, HCHT is a modular protein composed of a catalytic domain (GH18) associated to a Carbohydrate Binding Module (CBM) which is essential to hydrolyse crystalline chitin. If the catalytic domain GH18 is highly common in other GHs from animals, plants, fungi, bacteria, archea and viruses, its CBM (named ChBD) is much less conserved which makes the association between these two domains particularly intriguing. This work aims to demystify HCHT’s physiological function. Firstly, using competitive inhibition assays, we have highlighted the ability of ChBD to interact with chitooligosaccharides (GlcNAc1-2-4-6) which suggests that ChBD can potentially act as a lectin domain. Secondly, to better understand the molecular basis for chitin recognition, we have used homology modelling to build, with high confidence, the 3D structure model of ChBD. Based on this model, a specific set of residues has been selected for alanine scan mutagenesis which has allowed us to define the minimum chitin binding interface of the protein. Thirdly, Phylogenomic studies were performed to analyse the evolutionary history of the isolated catalytic and ChBD domains and understand how these domains were combined. Based on all these results, we discuss a new way of looking at HCHT where its ChBD would be the key determinant that has guided the catalytic domain from a basic metabolic function to a critical component of innate immunity in human. Finally, we propose a mechanism that explains how this enzyme could act at the molecular level to defend us against chitin-containing pathogens. [less ▲]

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See detailEffects of Music and Language Expertise on the Implicit Learning of Musical and Linguistic Structures?
Larrouy, Pauline ULg; DeChristen, Eleonore; Kolinsky, Régine

Poster (2015, August)

1. Background The cognitive consequences of music and language expertise are rarely compared. Recently, we observed different profiles in music and language experts in implicit learning of linguistic ... [more ▼]

1. Background The cognitive consequences of music and language expertise are rarely compared. Recently, we observed different profiles in music and language experts in implicit learning of linguistic structures of sung material (Larrouy-Maestri, Leybaert, & Kolinsky, 2013), with music experts performing better. Yet, as the language experts were speech therapists, this could reflect their formal, late language training. 2. Aims We aimed at comparing informal vs. formal language training and at examining the effect of dual expertise (in music and language) on the implicit statistical learning of musical and linguistic structures. We therefore used the sung material of Larrouy-Maestri et al. (2013) and tested the ability of music and/or language experts as well as of dual experts to implicitly learn the linguistic and/or musical structure of this material. 3. Method 14 music experts, 14 bi- or multi-linguals and 8 dual experts (bi- or multi-linguals also experts in music) were asked to listen attentively to 7.30 min of a continuous stream made out of 6 trisyllabic nonsense “words” sung on 6 three-tone melodies. Each “word” (defined by transitional probabilities) carried its specific melody, as melodic and linguistic transitional probabilities were congruent. A two-alternative forced-choice required choosing between “words” and “partwords”, either spoken (in the linguistic test) or instrumental (in the music test) was used to test participants’ learning of the linguistic or melodic structure. 4. Results Expertise modulated performance in the linguistic test when including the speech-therapists of our previous study (F(3, 49) = 5.92, p = .002, η2 = 0.28), who performed the worst. In the musical test, there was no significant group effect (p = .25), but one-sample t-tests showed that only the dual experts performed above chance, with 62.5% correct (p < .01). 5. Conclusions Whereas informal language training and music expertise lead to similar abilities to implicitly learn linguistic - but not musical - structure, this was not the case of formal language expertise. The combination of music and informal language expertise led to a particular profile, i.e., to the ability to learn simultaneously the musical and linguistic structures of sung material. [less ▲]

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See detailSensory quality of beef patties inoculated with strains of Carnobacterium maltaromaticum with potential as biopreservatives
Didimo Imazaki, Pedro Henrique ULg; Jacques-Houssa, Charlotte ULg; Kergourlay, Gilles ULg et al

Poster (2015, August)

Biopreservation is the use of naturally occurring microorganisms and/or their inherent antimicrobial compounds to extend shelf life and to enhance the safety of foods. The aim of the present study was to ... [more ▼]

Biopreservation is the use of naturally occurring microorganisms and/or their inherent antimicrobial compounds to extend shelf life and to enhance the safety of foods. The aim of the present study was to perform a sensory evaluation of beef patties inoculated with strains of C. maltaromaticum with potential as biopreservatives. Three different strains of C. maltaromaticum (CM_824, CM_827 and CM_829) isolated from vacuum packaged beef with long shelf life were selected for this study. An untrained panel was requested to make a sensory evaluation of raw and cooked beef patties 8 and 10 days after inoculation with the selected strains at 104 and 106 UFC/g and storage in high O2 atmosphere. This preliminary study permitted to evaluate the effect of three C. maltaromaticum strains on the sensory quality of beef patties. Strain CM_827 did practically not change the sensory attributes of beef patties. Samples inoculated with strain CM_824 and CM_829 received the worst scores for several of the tested descriptors. Therefore, further research on the biopreservative capacity of C. maltaromaticum should be conducted with strain CM_827. [less ▲]

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See detailReduced Order Modeling Techniques in Experimental Dynamic Substructuring
Roettgen, Dan; Dossogne, Tilàn ULg; Seeger, Benjamin et al

Poster (2015, August)

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See detailStroke Volume Estimation using Aortic Pressure Measurements and Aortic Cross Sectional Area
Kamoi, Shun; Pretty, Christopher G.; Chiew, Yeong Shiong et al

Poster (2015, August)

Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of ... [more ▼]

Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of measurement devices. Current devices for indirect monitoring of SV are shown to be inaccurate during sudden hemodynamic changes. This paper presents a novel SV estimation using readily available aortic pressure measurements and aortic cross sectional area, using data from a porcine experiment where medical interventions such as fluid replacement, dobutamine infusions, and recruitment maneuvers induced SV changes in a pig with circulatory shock. Measurement of left ventricular volume, proximal aortic pressure, and descending aortic pressure waveforms were made simultaneously during the experiment. From measured data, proximal aortic pressure was separated into reservoir and excess pressures. Beat-to-beat aortic characteristic impedance values were calculated using both aortic pressure measurements and an estimate of the aortic cross sectional area. SV was estimated using the calculated aortic characteristic impedance and excess component of the proximal aorta. The median difference between directly measured SV and estimated SV was -1.4ml with 95% limit of agreement +/- 6.6ml. This method demonstrates that SV can be accurately captured beat-to-beat during sudden changes in hemodynamic state. This novel SV estimation could enable improved cardiac and circulatory treatment in the critical care environment by titrating treatment to the effect on SV. [less ▲]

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See detailMathematical modeling of extracorporeal CO2 removal
Habran, Simon ULg; Dauby, Pierre ULg; Desaive, Thomas ULg et al

Poster (2015, August)

Extra¬cor¬poreal CO2 removal devices (ECCO2R) can be used in clinics to decarboxylate blood externally for patients suffering from pulmonary insufficiencies like acute respiratory distress syndrome. In ... [more ▼]

Extra¬cor¬poreal CO2 removal devices (ECCO2R) can be used in clinics to decarboxylate blood externally for patients suffering from pulmonary insufficiencies like acute respiratory distress syndrome. In this work, a model of the respiratory system coupled with such a device is proposed to analyze the decrease of CO2 partial pressure in blood as a function of blood flow through the device. This model provides a mathematical tool which could help clinicians to choose the optimal settings of ECCO2R. [less ▲]

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See detailThe Hydroxyl Nightglow Emissions on Earth, Venus and Mars
Soret, Lauriane ULg; Gérard, Jean-Claude ULg; Piccioni, G. et al

Poster (2015, August)

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See detailApplication of next generation sequencing for study and diagnosis of plant viral diseases in agriculture
van der Vlugt, René; Minafra, Angelanotio; Olmos, Antonio et al

Poster (2015, August)

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See detailModelling of the Nonlinear End-Systolic Pressure-Volume Relation and Volume-at-Zero-Pressure in Porcine Experiments
Davidson, Shaun M.; Kannangara, D. Oliver; Pretty, Christopher G. et al

Poster (2015, August)

The End-Systolic Pressure-Volume Relation (ESPVR) is generally modelled as a linear relationship between P and V as cardiac reflexes, such as the baroreflex, are typically suppressed in experiments ... [more ▼]

The End-Systolic Pressure-Volume Relation (ESPVR) is generally modelled as a linear relationship between P and V as cardiac reflexes, such as the baroreflex, are typically suppressed in experiments. However, ESPVR has been observed to behave in a curvilinear fashion when cardiac reflexes are not supressed, suggesting the curvilinear function may be more clinically appropriate. Data was gathered from 41 vena cava occlusion manoeuvres performed experimentally at a variety of PEEPs across 6 porcine specimens, and ESPVR determined for each pig. An exponential model of ESPVR was found to provide a higher correlation coefficient than a linear model in 6 out of 7 cases, and a lower Akaike Information Criterion (AIC) value in all cases. Further, the exponential ESPVR provided positive V0 values in a physiological range in6 out of 7 cases analysed, while the linear ESPVR produced positive V0 values in only 3 out of 7 cases, suggesting linear extrapolation of ESPVR to determine V0 may be flawed. [less ▲]

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See detailGenetic heritage of the Eastern Belgium Red and White breed, an endangered local breed
Colinet, Frédéric ULg; Bouffioux, Aude; Mayeres, Patrick et al

Poster (2015, August)

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See detailHow novice and expert drivers adjust their driving behavior when they feel drowsy?
Berastegui, Pierre ULg; Piette, Christine; François, Clémentine ULg et al

Poster (2015, July 29)

This paper aims to explore adaptive behaviors developed by drivers to prevent drowsiness. Specifically, we postulate that driving expertise is associated with better drowsiness awareness, allowing experts ... [more ▼]

This paper aims to explore adaptive behaviors developed by drivers to prevent drowsiness. Specifically, we postulate that driving expertise is associated with better drowsiness awareness, allowing experts to adequately adjust their driving behaviors when they feel drowsy. The present study was carried on a high-fidelity driving simulator coupled with an innovative system allowing objective sleepiness assessment based on EEG and Eye-tracking data. The Karolinska Sleepiness Scale was used to evaluate subjective drowsiness. The ratio between objective and subjective assessments gave an indicator of drowsiness awareness. Standard Deviation of Lateral Position (SDLP) was used as a measure of performance while driving speed and ocular fixations were recorded in order to highlight adaptive behaviors. 16 subjects were recruited from general population and categorized in two groups of expertise based on the Belgian Institute for Road Safety’s criteria. Our results show that expert drivers show better drowsiness awareness than novices and mobilize speed increasing and vigilance reallocation strategies to maintain satisfactory level of drowsiness. [less ▲]

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See detailProbing the conformational changes during desolvation of ions using orthogonal mobility methods (CE-IMS)
Far, Johann ULg; Kune, Christopher ULg; Delvaux, Cédric ULg et al

Poster (2015, July 29)

The transfer of ions from the solution to the gas phase is a critical step to produce « native species ». Coming from a highly solvating medium, ionic species will tend to find a new equilibrium ... [more ▼]

The transfer of ions from the solution to the gas phase is a critical step to produce « native species ». Coming from a highly solvating medium, ionic species will tend to find a new equilibrium conformation in the gas phase. The pathway to reach the thermodynamically stable conformation involves crossing potential barriers of different heights. When these barriers are too high compared to the internal energy of the ions, it will result in “partial memories” (as structural preservation) of the conformation in solution. In order to evaluate the effect of the solvent evaporation and of the various collision processes encountered by the ions in the mass spectrometer, we developed two strategies: The first strategy consists in comparing in a single experiment the shape of the ions in solution and in the gas phase. Data are obtained by coupling capillary electrophoresis with Ion Mobility Mass Spectrometry. Drift times in solution and in the gas phase are directly compared. Deviations from their correlation points out changes in folding upon desolvatation. Preliminary results show that among peptides issued from tryptic digest of BSA some of them clearly change their conformation during desolvatation. The second strategy consists in probing changes of conformation once the ions are in the gas phase. The ions are rapidly heating by collisions ions during their transfer to the IMS. The heating is obtained by increasing their collision energy, rapidly followed by thermalisation in the IMS cell. The ions may be kinetically trapped in their new conformations. This allows comparing barriers between different ions geometries. In summary this work intends to evaluate the extent of conformational “memory” of the ions of different nature for best experimental condition allowing “native mass spectrometry” [less ▲]

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

Poster (2015, July 27)

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

Poster (2015, July 26)

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

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

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

Poster (2015, July 21)

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

Poster (2015, July 18)

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

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

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

Poster (2015, July 16)

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

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

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

Poster (2015, July 16)

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

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

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See detailIsolation and identification of potential antimalarial compounds from endemic plants of Reunion Island
Bordignon, Annélise ULg

Poster (2015, July 16)

Malaria is known as the most important parasitic disease around the world with 584 000 malaria deaths worldwide in 2013 [1]. Due to the problem of increased parasite resistance, natural products from ... [more ▼]

Malaria is known as the most important parasitic disease around the world with 584 000 malaria deaths worldwide in 2013 [1]. Due to the problem of increased parasite resistance, natural products from endemic plants of Reunion Island, hot spot of promising biodiversity, could represent an important source of new antimalarial drugs. The aim of this thesis research focuses on the evaluation of potential antiplasmodial activity of medicinal plants from Reunion Island. A global screening of plants extracts from Reunion Island was performed on Plasmodium falciparum 3D7 chloroquine-sensitive strain revealed by colorimetric method as described in previous reports [2]. Monimia rotundifolia was then selected due to its promising in vitro activity against Plasmodium. Bioguided fractionation was realized using Prep HPLC techniques and led to the isolation of aporphine-type alkaloids from Monimia rotundifolia leaves dichloromethane extract. Further investigations are in process to confirm the antiplasmodial activities of these alkaloids and to determine their structures. References: [1] WHO, World Malaria report 2014. [2] Jansen O. et al., Evaluation of 13 selected medicinal plants from Burkina Faso for their antiplasmodial properties. J Ethnopharmacol 2010, 130:143-150. [less ▲]

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

Poster (2015, July 14)

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

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

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

Poster (2015, July 13)

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

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

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See detailSmall Heat Shock Proteins (sHSPs), specific markers of exercise-induced muscle damage
Hody, Stéphanie ULg; Simonet, Arnaud ULg; Lacrosse, Zoé ULg et al

Poster (2015, July 12)

Unaccustomed eccentric (ECC) exercise may cause exercise-induced muscle damage (EIMD) whereas repeating submaximal ECC sessions is known to prevent this damage. The present study aimed to better ... [more ▼]

Unaccustomed eccentric (ECC) exercise may cause exercise-induced muscle damage (EIMD) whereas repeating submaximal ECC sessions is known to prevent this damage. The present study aimed to better understand the molecular mechanisms underlying EIMD and subsequent adaptation. C57BL adult mice were submitted to different treadmill running protocols: IEE (intense ECC exercise), ET (ECC training), CT (concentric training), LT (level training), ET+IEE, CT+IEE. A 2D-DIGE proteomic analysis on mouse quadriceps muscles revealed that HSP25 and alpha-crystallin B chain were significantly more abundant in IEE, CT+IEE, ET+IEE and ET groups compared to unexercised mice. Interestingly, immunofluorescence analysis highlighted that all damaged fibers also showed positive staining for sHSPs. In contrast, sHSPs+ fibers are not necessarily damaged, suggesting that the sHSPs response precedes increased sarcolemma permeability. Our data demonstrate that ECC exercise specifically increases sHSPs expression which may represent an early marker of damage and/or adaptation of the muscle fibers to ECC contraction. [less ▲]

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See detailControlled clinical trial of repeated left prefrontal transcranial direct current stimulation in patients with chronic minimally conscious state
Thibaut, Aurore ULg

Poster (2015, July 08)

Thibaut A., Bruno MA., Wannez S., Donneau AF., Martial C., Chatelle C., Laureys S. Background: A recent study showed that single-session anodal transcranial direct current stimulation (tDCS) applied to ... [more ▼]

Thibaut A., Bruno MA., Wannez S., Donneau AF., Martial C., Chatelle C., Laureys S. Background: A recent study showed that single-session anodal transcranial direct current stimulation (tDCS) applied to the left dorsolateral prefrontal cortex (LDLPF) transiently improves consciousness in 43% of patients in minimally conscious state (MCS) (1). We here test the potential effects and safety of repeated tDCS in severely brain-damaged patients with MCS. Methods: In this double-blind cross-over sham-controlled experimental design, we delivered two sessions of repeated (5 days of stimulation) tDCS, either anodal or sham in a randomized order. We stimulated the LDLPF cortex (Figure 1) during twenty minutes in 20 MCS patients (12 men, aged 48±16 years, time since onset 78±95 months, 12 post-traumatic). Consciousness was assessed by the French adaptation of the Coma Recovery Scale Revised (CRS-R; 2) before and after each stimulation (Figure 2). Results: A treatment effect was observed for the comparison between CRS-R total scores at baseline and after 5 days of real tDCS (p<0.01). Behaviorally, 10/20 patients showed a tDCS- related improvement; 5 patients responded after the first stimulation and 5 other patients responded after 2, 3 or 4 days of stimulation (Figure 3). No side effect (e.g. epilepsy, sign of pain, drowsiness) was reported. Conclusion: Our results demonstrate that repeated (5 days) anodal LDLPF tDCS is safe and might improve signs of consciousness in about half of patients in MCS. It is important to note that the first session is not predictive for a future positive effect of the efficacy of the non-invasive electrical stimulation. References: 1. Thibaut A, Bruno MA, Ledoux D, Demertzi A, Laureys S. tDCS in patients with disorders of consciousness: sham-controlled randomized double-blind study. Neurology. 2014 Apr 1;82(13): p. 1112-8. 2. Schnakers C, Majerus S, Giacino J, Vanhandenhuyse A, Bruno MA, Boly M, Moonen G, Damas P, Lambermont B, Lamy M, Damas F, Ventura M, Laureys S. A French validation study of the Coma Recovery Scale-Revised (CRS-R). Brain Injury. 2008 Sep ;22(10): p. 786-92. [less ▲]

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See detailOpen pits or deep mines used for Underground Pumped Storage Hydroelectricity (UPSH): impacts on groundwater exchanges
Pujades, Estanislao ULg; Willems, Thibault ULg; Orban, Philippe ULg et al

Poster (2015, July 08)

UPSH using abandoned works is an attractive alternative to improve the efficiency of power plants, which cannot regulate the amount of electricity generated according to the demand (wind, solar or nuclear ... [more ▼]

UPSH using abandoned works is an attractive alternative to improve the efficiency of power plants, which cannot regulate the amount of electricity generated according to the demand (wind, solar or nuclear). UPSH plants can store (pumping water from an underground to an upper reservoir) or produce energy (releasing water from an upper to an underground reservoir) during the low or high demand periods. However, it is mandatory to determine 1) the impacts caused on aquifers and 2) the role played by the aquifer characteristics in order to assess the suitability of UPSH plants. Numerical simulations are developed in order to ascertain the groundwater flow impacts and the variables involved in the process. Given the earlier stages of our study, results are obtained considering regular pumping-injection cycles and simplifying the shape of the mine/open pit. The most noticeable effect consists in an oscillation of the groundwater. The hydraulic head around which groundwater oscillates, the magnitude of the oscillations and the time to achieve a pseudo-steady state (magnitude and head reached during oscillations do not vary anymore with time) depend on the boundaries, the parameters of the aquifer and the characteristics of the underground reservoir. [less ▲]

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

Poster (2015, July 07)

Detailed reference viewed: 16 (3 ULg)