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See detailIntegrated continuous flow photoreactors: Photooxidation of (L)-methionine with singlet oxygen
Emmanuel, Noémie ULg; Mendoza Gallego, Carlos ULg; Lismont, Marjorie ULg et al

Poster (2016, October 13)

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side ... [more ▼]

Development of photochemistry in macroscopic batch reaction vessels is hampered due to inherent limitations: light penetration remains superficial, resulting in inhomogeneous irradiation and hence to side-reactions or product degradation due to overexposure. The recent implementation of photochemical processes in microreactors under continuous-flow conditions appeared to be much more powerful than its batch analogue in terms of irradiation efficiency and light penetration. Furthermore, the fine control of residence time ensures an accurate control of the irradiation time, avoiding side-reactions and degradation. The photooxidation of (L)-methionine with singlet oxygen using Rose Bengal as a sensitizer was successfully implemented in a microreactor setup and led to total and selective conversion into methionine sulfoxide, an important building block for the organic synthesis of peptides or functionalized amino acid. The reaction was performed in 20 min while the same reaction in batch took 2h. [less ▲]

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See detailAlkylcobalt as source of radicals for the controlled polymerization of less activated vinyl monomer
Demarteau, Jérémy ULg; Cordella, Daniela ULg; Kermagoret, Anthony et al

Poster (2016, October 13)

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See detailDesign and synthesis of Fe2O3 nanoparticles/N-doped porous carbon structures as high performance electrode for lithium ion battery
Alkarmo, Walid ULg; Ouhib, Farid ULg; Aqil, Abdelhafid ULg et al

Poster (2016, October 13)

Thanks to their fascinating physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, three dimensionally (3D) interconnected carbon porous ... [more ▼]

Thanks to their fascinating physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, three dimensionally (3D) interconnected carbon porous frameworks have emerged as attractive materials for various electrochemical energy storage/conversion devices, including Li-ion batteries (LIBs), Li−S batteries, supercapacitors and fuel cells. In this context, a hierarchically structured macro- and mesoporous N-doped carbon with dispersed Fe2O3 nanoparticles (NDC@Fe2O3) is prepared by thermal treatment of a novel composite composed by PMMA particles decorated by graphene oxide (GO), PPy and iron salts. The NDC@Fe2O3 composite exhibited high surface area with a hierarchical pores structure. The combination of Fe2O3 nanoparticles with porous carbon to form hybrid anode has been an efficient way to maintain the electronic integrity of the whole electrode since the carbon acts as a buffer layer to accommodate the volume variation and to provide multidimensional electron transport pathways during the charge/discharge process. [less ▲]

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See detailWalking droplets in confined geometries
Filoux, Boris ULg; Hubert, Maxime ULg; Schlagheck, Peter ULg et al

Poster (2016, October 12)

When gently placing a droplet onto a vertically vibrated bath, under specific conditions, coalescence may be avoided. The drop bounces permanently. Upon increasing the forcing acceleration, the drop ... [more ▼]

When gently placing a droplet onto a vertically vibrated bath, under specific conditions, coalescence may be avoided. The drop bounces permanently. Upon increasing the forcing acceleration, the drop interacts with the wave it generates, and becomes a walker [1,2]. Recently, some 2D confining systems for walking droplets have been developed: cylindrical cavity, harmonic potential or the use of Coriolis force [3,4]. In addition, the interactions between two identical walkers have been studied in a 2D case [5]. Nevertheless, no study focuses on 1D dynamics and their properties. In this work, we show it is possible to confine a walker in a quasi mono-dimensional geometry by using a submerged annular cavity. We focus on the interactions between droplets, and show the interdistance quantization. Then, we study the speed of pairs of walkers and show that the distance between the drops affects the group speed: the closer the drops are, the faster they move. We also propose a numerical model to characterize the distance quantization, and the evolution of the speed of a string of droplets. Finally, we investigate the case of a string of droplets. We discuss the influence of the number of droplets and the distance between droplets on the string speed. 1. Y. Couder, S. Protière, E. Fort, and A. Boudaoud, Nature 437, 208 (2005).
 2. S. Protière, A. Boudaoud, and Y. Couder, J. Fluid Mech. 554, 85 (2006).
 3. S. Perrard, M. Labousse, M. Miskin, E. Fort, and Y. Couder, Nat. Commun. 5, 3219 (2014).
 4. M. Labousse and S. Perrard, Phys. Rev. E 90, 022913 (2014).
 5. C. Borghesi, J. Moukhtar, M. Labousse, A. Eddi, E. Fort, and Y. Couder, Phys. Rev. E 90, 063017 (2014). [less ▲]

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See detailMOSSBAUER SPECTROSCOPY AS A COMPLEMENTARY TECHNIQUE OF X-RAY DIFFRACTION TO INVESTIGATE ELECTRODE MATERIALS FOR ALKALI-ION BATTERIES
Mahmoud, Abdelfattah ULg; sougrati, Moulay Tahar; karegeya, claude et al

Poster (2016, October 09)

Lithium-ion batteries (LIBs) have been widely applied as a power source for portable electronics, stationary energy storage systems, and electric vehicles. Nevertheless, as lithium resources continue to ... [more ▼]

Lithium-ion batteries (LIBs) have been widely applied as a power source for portable electronics, stationary energy storage systems, and electric vehicles. Nevertheless, as lithium resources continue to decline worldwide and Li in the Earth’s crust is unevenly distributed as minor-metal. Na-ion batteries are considered to be an alternative to Li-ion batteries owing to the natural abundance of sodium. Indeed, Sodium-ion (Na-ion) batteries are expected to become part of the mix of technologies that will meet the challenges of energy storage. Electrode materials are the most important components in the operation and the performances of Alkali-ion batteries. New electrode materials are required to increase the energy density of Li/Na-ion batteries [1]. Fe based negative electrode materials for Li-ion batteries have been previously investigated to evaluate the electrochemical performances and elucidate the electrochemical reaction mechanisms. Mössbauer spectroscopy has been applied to a variety of fields including chemistry, physics, geology, biology…. In the domain of energy storage, Mössbauer spectroscopy has been used as a powerful tool to investigate the local electronic and structural properties of electrode materials and to determine their reaction mechanisms during charge and discharge of Li/Na-ion batteries [2]. In this poster, we will show from some selected examples how Mössbauer spectroscopy when used with X-ray diffraction can help to improve the performances of electrode materials for Alkali-ion batteries. References 1. Sougrati MT, Darwiche A, Liu X, Mahmoud A, Hermann RP, Jouen S, Monconduit L, Dronskowski R, Stievano L: Transition-metal carbodiimides as molecular negative electrode materials for lithium- and sodium-ion batteries with excellent cycling properties. Angew Chem Int Ed., 2016, 55: 5090-5095. 2. Brisbois, M., Caes, S., Sougrati, M. T., Vertruyen, B., Schrijnemakers, A., Cloots, R., Eshraghi, N., Hermann, R. P., Mahmoud, A., Boschini, F. Na2FePO4F/Multi-Walled Carbon Nanotubes for Lithium-Ion Batteries_ Operando Mössbauer Study of Spray- Dried Composites. Solar Energy Materials and Solar Cells 2016, 148, 67–72. Acknowledgment A. Mahmoud and F. Boschini would like to kindly thank Wallonie regions for the financial support. [less ▲]

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See detailImplication of Importin-8 in mouse brain development
Nganou, Gerry ULg; Denijs, Laurence; Lakaye, Bernard ULg et al

Poster (2016, October 08)

Regulation of nucleocytoplasmic transport of proteins by the karyopherin superfamily is critical for cell physiology as it controls mainy fundamental processes such as division, differenciation, migration ... [more ▼]

Regulation of nucleocytoplasmic transport of proteins by the karyopherin superfamily is critical for cell physiology as it controls mainy fundamental processes such as division, differenciation, migration, adaptation to external environment etc. Beside this fundamental role, ß1 and ß2 members of this superfamily are also implicated in mitosis and ciliary entry respectively. Importin-8 (IPO8), a member of the β-karyopherin family, is reported to control the transport Ago-2, c-Jun and Smad-4 for example, three proteins important for brain development. First, we have verify the subcellular localisation of IPO8 in HEK and hTert cells. No colocalisation with either the mitotic spindle or the primary cilia could be observed. So it seems IPO8 only plays a role in nuclear transport of proteins. Then we have assessed the expression of IPO8 in mouse brain by In Situ Hybridization at various embryonic (E12, E14, E18) and post natal age (P5, P60). A strong expression was observed during embryonic stages, and especially in the ventricular zone and the cortical plate of the cerebral cortex and the ganglionic eminences both at E14. Therefore, the implication of IPO8 in the radial migration has been assessed by in utero electroporation of shRNA at E14. Three days after IUE, we observed that neuroblast accumulates in the Intermediate zone (IZ) and do not reach the cortical plate (CP) in constrast to the control condition. This effect can be corrected by coexpressing a form of IPO8 that is not targeted by the shRNA, demonstrating the specificity of the effect. In conclusion, regarding its role in transport, IPO8 could modulate neurons migration in the developing brain and could be also at the origin of some diseases associated with neurons migration defects. [less ▲]

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See detailOccurence of the new variant of rabbit haemorrhagic disease virus (RHDV2) in wild populations of rabbits in Southern Belgium
Volpe, Rosario ULg; Lesenfants, Christophe ULg; Paternostre, Julien ULg et al

Poster (2016, October 07)

Rabbit haemorrhagic disease (RHD) is a highly infectious and fatal disease of the European rabbit (Oryctolagus cuniculus), responsible for important economic losses in the rabbit industry. The ... [more ▼]

Rabbit haemorrhagic disease (RHD) is a highly infectious and fatal disease of the European rabbit (Oryctolagus cuniculus), responsible for important economic losses in the rabbit industry. The aetiological agent of the disease is a RNA virus (RHDV, Lagovirus, Caliciviridae) first detected in China in 1984. Currently RHDV is endemic in most parts of Europe, Asia and North Africa. Phylogenetic analyses of RHDV strains have identified 3 distinct groups : the classic RHDV, the variant RHDVa and RHDV2. This latter has been detected in France for the first time in 2010 in domestic and wild rabbits (Le Gall-Reculé G et al., 2013) and since then has spread throughout Europe, replacing the circulating RHDV/RHDVa strains in most european countries. RHDV2 has already been detected in Belgium in rabbitries (Marlier D et al., 2014). Here, we report for the first time the presence of RHDV2 in wild rabbits in Southern Belgium. In november 2015, the Surveillance Network of Wildlife Diseases received seven dead wild rabbits for necropsy. The discovery of 7 fresh carcasses found at the same time in a same area (Hainaut province) emphasised the infectious or intoxication hypothesis as cause of death. Postmortem examinations were performed at the Faculty of Veterinary Medicine (FVM) of the University of Liege according to a systematic protocol based on gross lesions, histopathological and targeted microbiological analysis. For necropsy, each rabbit (1) was weighted and age was determined by the presence/absence of the distal ulna protuberance, (2) stomach was investigated to exclude poison, (3) spleen was systematically driven into Yersinia CIN culture media for detection of Yersinia pseudotuberculosis, (4) lungs and livers were systematically (a) packaged into 10% formaldehyde solution for histopathology analysis (Service of Pathology, FVM) and (b) frozen at -20°C for RHDV analysis (Scanelis Laboratory,Toulouse, France) and finally (6) feces were gathered for parasitology (Service of Parasitology, FVM). At necropsy, animals (5 adults: 3 males/2 females and 2 juveniles: 1 male/1 female) were in good condition. No hematomas or broken bones were detected, only one displayed clues of diarrhoea. Examinations of the carcasses showed congestion of lungs/kidneys and livers were macroscopically normal. No foreign body or suspicious particles was seen in the stomachs, only one rabbit was hardly infested by tapeworms in the gut. Histopathological examination revealed haemorragic lung lesions in one animal while 5 of them presented severe necrotic hepatitis, sometimes associated with peri-angiocholitis. Only one animal presented an abnormal high rate of coccidia in feces. Samples of livers were sent to Scanelis Laboratory for RHDV RT-qPCR diagnostic. The results were positive for the new variant RHDV2 in 5 out of the 7 rabbit livers. All the samples were negative for the classic RHDV. To determine if RHDV2 was already present before 2015 in wild rabbits in the region, we tested a series of livers that had been collected in 2013 and 2014 for a retrospective study. Among the 25 rabbit livers checked, 12 presented necrotic hepatitis and were sent for analysis. Ten were confirmed positive by RT-qPCR for RHDV2. [less ▲]

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See detailPhenotypic plasticity in a fossorial toad from a Pacific xeric forest (Ecuador)
Székely, Diana ULg; Szekely, Paul; Denoël, Mathieu ULg et al

Poster (2016, October 06)

For amphibians, optimal size at metamorphosis is determined by a trade-off between opportunities for growth and risks of mortality in aquatic and terrestrial habitats, and many species show a high degree ... [more ▼]

For amphibians, optimal size at metamorphosis is determined by a trade-off between opportunities for growth and risks of mortality in aquatic and terrestrial habitats, and many species show a high degree of plasticity in time and size at metamorphosis that allow them to adapt to unpredictable environments. We used as model a neotropical anuran species, the Pacific horned frog, Ceratophrys stolzmanni, that inhabits the Tumbesian dry forests of southwestern Ecuador, and lays its eggs in lentic habitats of variable size and unpredictable duration. We investigated (i) how tadpoles time their metamorphosis in order to escape a rapidly drying aquatic habitat, and (ii) the consequences of metamorphosis plasticity on the immediate and mid-term fitness of individuals. We conducted two experiments; in the first one we exposed 36 tadpoles to one of three water levels treatments: constant high, decreasing and constant low. Tadpoles that were raised in decreasing or low water level metamorphosed on average 13% and 10% faster than the ones from constant high water level, but at a lower body size and mass. Growth rates were among the highest recorded for tadpoles and individuals from the constant high water level treatment grew at a much faster rate than the others. In a second experiment, we sampled 72 freshly metamorphosed (Gosner stage 45) C. stolzmanni individuals of assorted sizes (SVL between 23.8 and 47.9 mm, body weight between 1.2 and 11.9 g). From this spectrum of sizes, we selected the 21 largest and 22 smallest individuals and evaluated the effects of body size at metamorphosis on trophic and locomotory performance parameters. We determined their growth rate and survival over the course of an activity season (i.e., two months). Our results show that bigger size at metamorphosis is correlated with better survival chances and performance. Larger individuals were more mobile, had bigger gape width and better survival rates (95% compared to 64% for small individuals). Growth rates were not correlated with initial size, and small individuals were capable of increasing their size at a higher rate. This indicates that, although size at metamorphosis has an immediate impact on fitness, smaller individuals are able to compensate with an increased growth rate. [less ▲]

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See detailAgeism among medical students
Corvol, Aline; Missotten, Pierre ULg; Gentric, Armelle et al

Poster (2016, October 06)

Introduction Negative stereotypes concerning elderly persons are widespread in general population. When they are adopted by health care professionals, it can decrease the quality of care or even induce ... [more ▼]

Introduction Negative stereotypes concerning elderly persons are widespread in general population. When they are adopted by health care professionals, it can decrease the quality of care or even induce disability. That’s why medical curriculum should take the question of ageism in consideration. Though, little is known about ageism among medical students and its determinants. Method We conducted a study on Rennes University (France) medical students (year 2 to year 6) using on line questionnaire. Validated tools, such as Fraboni Scale of Ageism, and innovating ones, such as verbal fluency task about aging and youth, have been proposed. Results have been compared with those obtained in Liège, Belgium, and analyzed according to age, gender, year of study, and geriatric training. Results Response rate was above 90%, leading to 814 replies. Replies, especially at the verbal fluency task, demonstrate the strength of negative stereotypes, with similar results in Rennes and Liège. No effect of courses or internship in geriatrics has been identified. Negative stereotypes seem lower in female students, and in those who have regular contact with elderly persons, especially if these contacts are good. Key conclusion Ageism is widespread in French medical students, whatever the year of study. Enhancing positive contacts between elderly persons and medical students may be an effective way to prevent it, but may be challenging to implement. Further studies could focus on implicit stereotypes to underplay the social desirability bias. [less ▲]

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See detailMise en place de pratiques agricoles de conservation: quel impact sur la vie du sol
Degrune, Florine ULg; Boeraeve, Fanny ULg; Vandenbol, Micheline ULg et al

Poster (2016, October 04)

Le projet Farm4Future a été lancé en 2015 et consiste en un suivi intégré d’un réseau d’exploitations agricoles belges en cours de transition vers des pratiques dites « de conservation ». Les ... [more ▼]

Le projet Farm4Future a été lancé en 2015 et consiste en un suivi intégré d’un réseau d’exploitations agricoles belges en cours de transition vers des pratiques dites « de conservation ». Les exploitations étudiées dans le cadre de ce projet sont caractérisées par des changements de gestion incluant notamment : (1) des associations de culture, (2) des couverts permanents, (3) une réduction du travail du sol et (4) l’introduction de structures vertes telles que les haies ou les bandes fleuries. Afin d’évaluer le potentiel agronomique et écologique de ces systèmes agricoles, une série de mesures ont été effectuées dans deux types de sol aux propriétés texturales contrastées : sable limoneux et un limon sableux. Afin d’obtenir un point de comparaison, les mêmes mesures ont été effectuées sur les parcelles des agriculteurs voisins restés en intensif et conventionnel. Parmi ces mesures, nous étudions la réponse de plusieurs indicateurs biologiques de qualité des sols telle que la diversité microbienne. L’étude a démontré un effet du type de pratiques agricoles sur la diversité microbienne en fonction du type de sol. Nous avons également identifié les microorganismes sensibles au type de pratiques agricoles. Cependant, l’étude nous amène à démontrer une grande hétérogénéité de réponses au sein de chacun de ces groupes. En effet, même si certains grands groupes sont globalement plus abondants sous pratiques de conservation (ou conventionnel), la réponse des microorganismes au sein de ces groupes à des niveaux taxonomiques plus fins (genre ou espèce) n’est pas uniforme. Aujourd’hui, même si les outils moléculaires de séquençage à haut débit ont permis de mettre en lumière l’incroyable diversité microbienne des sols, les services écosystémiques rendus par ces microorganismes sont encore très peu connus car moins de 1% des organismes est cultivable en laboratoire. [less ▲]

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See detailThe functional-biogeography of the reef fishes in the Gulf of California: over-importance of a handful of sites
Olivier, Damien ULg; Reyes Bonilla, Hector

Poster (2016, October 03)

Functional biogeography is a new discipline allowing to link biogeographical patterns of trait and species diversity. This new area of research has a role in conservation policy because it permits to ... [more ▼]

Functional biogeography is a new discipline allowing to link biogeographical patterns of trait and species diversity. This new area of research has a role in conservation policy because it permits to create functional maps to highlight hotspots of biodiversity. In this study, we evaluate the taxonomic and functional diversity of the reef-fishes in 30 “archipelagoes” widespread along the Gulf of California (GOC). The question before us is to highlight areas requiring a particular intention in conservation policy because they represent a large part of the legacy of reef-fish diversity in the GOC. To do so, we used a recently developed method to classify the reef-fishes species of the GOC in functional entities (FEs). The FEs are based on unique combinations of six categorical traits known to influence the functional role of fishes (e.g. size, diet…) and their number represent the level of functional diversity of the community. The results showed that the Baja California Sur has the most diversified reef-fishes community, both taxonomically and functionally (more than 90% of the species and of the functional diversity are represented). This result is mainly due to four archipelagoes that present a dazzling diversity, i.e. Carmen, San José, Espiritu Santo and Cerralvo. Each of these islands includes 60% or more of the taxonomic and functional diversity of the GOC. Two of these archipelagoes benefit of a protection level through the National Parks of Loreto and Espiritu Santo. However, the former is poorly functioning and the latter is under evaluation. The outcomes of the present study provide a global map of the reef-fishes diversity through the GOC, in term of species number and functional diversity. These results allow the identification of four major hotspots of diversity that should require a particular attention to preserve the legacy of reef-fishes diversity in the GOC. [less ▲]

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See detailThe peroxisome proliferator-activated receptor Alpha (PPARA) is expressed in non-somatotroph pituitary adenomas : a potential therapeutic target ?
Rotondi, S; Polidoro, MA; Morace, R et al

Poster (2016, October)

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See detailBreaking Bad News: the TAKE five program.
GILLET, Aline ULg; VAN CAUWENBERGE, Isabelle ULg; TUBES, Rebecca ULg et al

Poster (2016, October)

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See detailADAM28 - Generation of a conditional ADAM28 knock-out mouse Implication of ADAM28 in metastasis dissemination
Gérard, Catherine ULg; Rocks, Natacha ULg; Carnet, Oriane ULg et al

Poster (2016, October)

Introduction: ADAMs (a disintegrin and metalloproteinase) and ADAMTS proteinases (a disintegrin and metalloproteinase with thrombospondin motifs) are MMP (matrix metalloproteinase) -related enzymes ... [more ▼]

Introduction: ADAMs (a disintegrin and metalloproteinase) and ADAMTS proteinases (a disintegrin and metalloproteinase with thrombospondin motifs) are MMP (matrix metalloproteinase) -related enzymes, bearing a multi-domain structure. ADAM28 is a multipotent membrane-bound proteinase and its expression in tissues derived from the foregut in embryonic tissues suggests its involvement in the organogenesis of the respiratory tract. Moreover, ADAM28 is highly overexpressed in non-small-cell lung cancer samples. Notably through a global proteomic approach, we recently identified an upregulation of ADAM28 after induction of lung inflammation in a mouse model of asthma. In addition to data published in the literature and to our findings about ADAM28 expression in various pathological tissues, intrinsic characteristics of this proteinase argue for considering it as a potential regulator of cellular signalling pathways leading to an inflammatory pulmonary microenvironment and, eventually, to carcinogenesis. Indeed, ADAM28 bears an active catalytic domain and interacts in a non-proteolytic manner with some integrins (α4β1) and some P-selectin ligands involved in inflammatory cell migration. ADAM28 was also reported to display the capacity to cleave key mediators such as Von Willebrand factor, IGFBP3 (Insulin-like growth factor-binding protein 3) and CTGF (Connective Tissue Growth Factor). Very recently, ADAM28 was shown to shed pro-TNF-alpha suggesting an important role in tumour control. The present project aims at characterizing molecular mechanisms leading to tumour development in lungs. In the first part of this work, we intend to characterize the effects of ADAM28 depletion on physiological and pathological processes such as tumor development and metastatic dissemination in ADAM28 conditional knock-out mice. Methods: To understand the implication of ADAM28 in lung tumour development we instillated lungs of mice displaying a full knock-out genotype for ADAM28 with Lewis Lung Carcinoma cells and B16K1 melanoma cells. ADAM28 KO mice were also injected intravenously and a subcutaneously with these tumour cells. Results: There is no spontaneous phenotype for ADAM28 full knock-out animals. Preliminary results show an impaired lung tumors engrafment in ADAM28 wild type animals when compared to heterozygous or knock out littermates. Conclusion: This unique mouse strain provides a very precious tool to further investigate ADAM28 implication in various disease models including tumour growth and dissemination. The role of ADAM28 as a pro-tumor factor is widely described in the literature whereas our results suggest that ADAM28 has an anti-tumor function. [less ▲]

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See detailMultimodal Connectivity-Based Parcellation of the Brain
Reuter, Niels; Plachti, Anna; Genon, Sarah ULg et al

Poster (2016, October)

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See detailRobust discriminant analysis based on the joint graphcial lasso estimator
Aerts, Stéphanie ULg; Croux, Christophe; Wilms, Ines

Poster (2016, October)

Linear and Quadratic Discriminant Analysis (LDA/QDA) are the most often applied classification rules under the normality assumption. When there is not enough data, the quadratic rule, which requires the ... [more ▼]

Linear and Quadratic Discriminant Analysis (LDA/QDA) are the most often applied classification rules under the normality assumption. When there is not enough data, the quadratic rule, which requires the estimation of one precision matrix in each class, is often replaced by the linear one, based on the homoscedasticity assumption. This strong assumption is however rarely verified in practice and ignores the intrinsic différences between groups that may be of particular interest in the classification context. In this aper, alternatives to the usual maximum likelihood estimates for the precision matrices are proposed that borrow strength across classes while allowing for heterogeneity at the same time. This results in a classifier that is intermediate between QDA and LDA. Moreover, our estimator is sparse: the undesirable effect of uninformative variables is reduced. The performance of the method is illustrated through simulated and real dataset examples. [less ▲]

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See detailStudy of the SV2A protein role in Epilepsy.
Bartholomé, Odile ULg; Van Den Ackerveken, Priscilla ULg; Wislet, Sabine ULg et al

Poster (2016, October)

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See detailLRP4 mutations in bilateral renal agenesis with severe limb deficiencies
JACQUINET, Adeline ULg; LEE, Anna F.; SWENERTON, Anna et al

Poster (2016, October)

Introduction : Severe limb deficiencies have been reported in association with bilateral renal agenesis in several syndromes. Recently, truncating mutations in LRP4 have been associated with a lethal ... [more ▼]

Introduction : Severe limb deficiencies have been reported in association with bilateral renal agenesis in several syndromes. Recently, truncating mutations in LRP4 have been associated with a lethal autosomal recessive form of Cenani-Lenz syndrome (CLS). The objectives of our study was to delineate the phenotype of the third fetus, and through a search of syndromes, identify a group of disorders with overlapping phenotypes that may be allelic with CLS or due to mutations in the same pathway. Results : A male fetus at 22 weeks’ gestation was found to have bilateral renal agenesis by ultrasound. The pregnancy was interrupted and autopsy and skeletal survey revealed shortening of forearms and legs below the knees, radioulnar synostosis, foreshortened triangular shaped tibia and fibula, and oligosyndactyly with disorganized metacarpals, metatarsals and phalanges. Bilateral renal agenesis, absent ureters and small bladder were confirmed. Additional features included downslanting palpebral fissures, high-arched palate, small mouth, low-set and posteriorly rotated ears, nuchal oedema, pulmonary hypoplasia, hypospadias and absent olfactory nerves. An autosomal recessive disorder was suspected, given a prior obstetric history of termination at 18 weeks for unilateral limb anomalies and cleft lip. Based on the aforementioned renal and limb anomalies, the lethal form of CLS was considered. Sequencing of LRP4 identified a paternally inherited variant (c.919+3G del) and a maternally inherited variant (c.4808T>A ;p.Ile1603Val). Both variants were rare in the general population and bioinformatically predicted to be damaging. We compared the phenotype with the two previously reported fetuses as well as with syndromes and disorders that may present prenatally with genitourinary anomalies plus acromesomelia of upper and lower limbs. We found significant overlap with a subset of cases of acro-renal-uterine-mandibular syndrome presenting with high-arched palate plus or minus micrognathia and microglossia, severe limb anomalies affecting the middle and distal segments, oligosyndactyly, renal agenesis, uterine anomalies and absence of olfactory nerves. Conclusion : Based on the clinical features seen in three lethal cases of CLS, we propose that acro-renal-uterine-mandibular syndrome may be allelic with CLS or due to mutations in the molecular pathway involving LRP4. [less ▲]

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See detailRegulation of breast carcinoma cell proliferation and apoptosis by type I collagen aging and 3D confinement involves differential activation of DDR1
Saby, Charles; Rammal, Hassan; Magnien, Kevin et al

Poster (2016, October)

During breast carcinoma development, cells are confronted to a type I collagen-rich environment which induces anti-proliferative and pro-apoptotic effects (Maquoi et al., Oncogene, 2012). These effects ... [more ▼]

During breast carcinoma development, cells are confronted to a type I collagen-rich environment which induces anti-proliferative and pro-apoptotic effects (Maquoi et al., Oncogene, 2012). These effects occurred only in 3D cell matrix and involved Discoidin Domain Receptor 1 (DDR1) but not β1 integrin (Assent et al., PlosOne, 2015). During aging, type I collagen undergoes post-translational modifications which have a detrimental effect on type I collagen fibrillar organization (Aït-Belkacem, J Biomed Optics, 2012 ; Guilbert et al., Oncotarget, 2016). This property is well known to be requested to activate DDR1. Here, we address the effect of type I collagen aging on cell proliferation inhibition and apoptosis induction in breast carcinoma cells in 3D cell confinement system. Type I collagen was extracted from tail tendons of 2 months (adult) and 2 years (old) rats, and MCF-7 and ZR-75-1 cells were used as an experimental model. We provide evidence for a decrease in cell proliferation by adult collagen but not by old one. This effect involves a higher phosphorylation of DDR1 by adult collagen when compared to the old one. Inhibition of DDR1 kinase activity by the specific inhibitor DDR1-IN-1 induced an increase in cell proliferation to a level similar to that observed in old collagen. An increase in cell proliferation was also observed using siRNA targeting DDR1 mRNA. At the opposite of old collagen, adult collagen was also able to trigger apoptosis by inducing an increase in expression of the pro-apoptotic protein (BIK). Inhibition of DDR1 kinase activity induced a decrease in BIK expression and apoptosis. Our data support the concept that aging contributes to the loss of the growth suppression and apoptotic effect of collagen on breast carcinoma, but only in 3D cell confinement model, by inactivating the DDR1-BIK signaling axis via a downregulation of DDR1 activation. [less ▲]

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See detailStudy of the effect of thin ALD oxide coatings on the stability of silver nanowire based transparent electrodes
Aghazadehchors, Sara; Nguyen, Viet; Lagrange, Mélanie et al

Poster (2016, October)

Current research on new Transparent Conductive Materials focuses on emerging materials such as carbon-based materials, graphene or metallic nanowire networks. The latter concern mainly silver nanowires ... [more ▼]

Current research on new Transparent Conductive Materials focuses on emerging materials such as carbon-based materials, graphene or metallic nanowire networks. The latter concern mainly silver nanowires (AgNW). Although AgNW networks seem to approach ITO values in terms of optical transparency and electrical sheet resistance, (90% and 10 Ω/sq respectively) [1], overcoming a rather poor thermal and electrical stability still remains a challenge. While most device fabrication processes require thermal annealing steps to optimize their electrical properties, heating can modify AgNW network morphology. Moreover, when used as transparent heaters, an electrical current induces specimen heating (due to Joule effect) and then imposing AgNW network to be resistant to heat. One way to improve thermal stability of AgNW networks is to use a thin layer of a passivating metal oxide (such as ZnO or TiO2) which induces stability improvements [2]. So far, our group has studied the effect of a thin layer of TiO2 deposited by ALD on the thermal and electrical stability of AgNWs networks. Our studies show that even a TiO2 layer as thin as 5 nm can lead to an extension of thermal stability from 270 °C to 420 °C. The oxide coating also increases the value of the electrical failure voltage. This stability enhancement comes with nearly no change in optical transparency (less than 1%). Currently we are replacing the ALD deposition method with a new approach called Spatial ALD (SALD). This technique does not require vacuum, it is much faster than conventional ALD and is easily scalable [3]. Here we will present a comprehensive study of the effect of deposition parameters, passivation film thickness on the electrical and optical properties of AgNWs based transparent electrodes. Optimized parameters will allow the integration in devices such as transparent heaters. We will demonstrate that adding a passivation layer increases the breakdown voltage, making the devices stable at higher voltage or temperature. References: [1] Lagrange, M., Langley, D. P., Giusti, G., Jiménez, C., Bréchet, Y., & Bellet, D. (2015). Optimization of silver nanowire-based transparent electrodes: effects of density, size and thermal annealing. Nanoscale, 7(41), 17410- 17423. [2] Kim, A., Won, Y., Woo, K., Kim, C. H., & Moon, J. (2013). Highly transparent low resistance ZnO/Ag nanowire/ZnO composite electrode for thin film solar cells. ACS nano, 7(2), 1081-1091. [3] Muñoz-Rojas, D., & MacManus-Driscoll, J. (2014). Spatial atmospheric atomic layer deposition: a new [less ▲]

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See detailUnexpected high levels of Cobalamin (Vitamin B12): Numerous interferences are decreased by PEG treatment.
LADANG, Aurélie ULg; VRANKEN, Laura ULg; CAVALIER, Etienne ULg

Poster (2016, October)

Cobalamin (Vitamin B12) deficiency is a common cause of anemia. High levels of serum cobalamin is mainly due to cobalamin supplementation. It has also been associated with hematological malignancies ... [more ▼]

Cobalamin (Vitamin B12) deficiency is a common cause of anemia. High levels of serum cobalamin is mainly due to cobalamin supplementation. It has also been associated with hematological malignancies, liver or renal diseases. Cobalamin is sometimes found elevated in autoimmune disorders and infectious diseases but concerns are raised on the fact that those serum increases might be due to interference with immunoassays. Those data’s shed the lights on the high prevalence of interference in patients with unexpected high cobalamin level. Precipitation with PEG appears to be an easy and costless method to increase the reliability of cobalamin dosage. In accordance with our results, we recommand to treat systematically every serum with a cobalamin >1500 ng/L. [less ▲]

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See detailInvestigating the potential of Cymodocea nodosa (Ucria) Ascherson as a coastal carbon sink coupling marine habitat cartographies and in situ nondestructive sampling
Abadie, Arnaud ULg; Richir, Jonathan ULg; Pieraccini, Riccardo ULg et al

Poster (2016, October)

Seagrass meadows are major carbon sinks, trapping about 10% of the total CO2 sequestrated in the oceans. In the Mediterranean, a major focus has been made on the climax species Posidonia oceanica (L ... [more ▼]

Seagrass meadows are major carbon sinks, trapping about 10% of the total CO2 sequestrated in the oceans. In the Mediterranean, a major focus has been made on the climax species Posidonia oceanica (L.) Delile, while other species remained little studied. In the framework of the STARECAPMED project, we thus chose to study Cymodocea nodosa (Ucria) Ascherson, a pioneer species with a rapid turnover and an expected high stocking capacity. Furthermore, the area covered by that species has been largely underestimated. In order to fill these two knowledge gaps, we first mapped all seagrass habitats within a Mediterranean bay (Calvi, Corsica, France) using side scan images, aerial photographs and ground truths. This cartography was followed by seasonal in situ density measurements and non-destructive shoot sampling (leaf cutting). Samplings were performed at different depths (5 to 23 m depth) in 6 contrasted stations (small patchy meadows to continuous beds) in order to cover all the existing facies of the bay. Elementary contents (carbon, nitrogen and stable isotope ratios) were measured in laboratory. This first work shows that C. nodosa meadows in Calvi Bay cover an area of 0.498 km2. Carbon stocks of the leaves reached 0.25 tons in winter and 2.72 tons in summer. Their nitrogen contents showed a marked seasonality with a maximum value of 0.020 mgN.m-2 in July and a minimum value of 0.005 mgN.m-2 in March. Some modifications in the trophic conditions of the water column at several stations were put in an obvious through the N stable isotopes values, mostly during the summer period. The actual underestimation of the area covered by that species in Calvi Bay has been properly mapped thanks to side scan sonar techniques revealing, together with elementary content analysis, its importance in the carbon balance of coastal areas. [less ▲]

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See detailA membrane-type- matrix metalloproteinase (MT1-MMP) - discoidin domain receptor 1 axis regulates collagen-induced apoptosis in breast cancer cells
Assent, Delphine; Bourgot, Isabelle ULg; Hennuy, Benoit et al

Poster (2016, October)

During tumour dissemination, invading breast carcinoma cells become confronted with a reactive stroma, a type I collagen-rich environment endowed with anti-proliferative and proapoptotic properties. To ... [more ▼]

During tumour dissemination, invading breast carcinoma cells become confronted with a reactive stroma, a type I collagen-rich environment endowed with anti-proliferative and proapoptotic properties. To develop metastatic capabilities, tumour cells must acquire the capacity to cope with this novel microenvironment. How cells interact with and respond to their microenvironment during cancer dissemination remains poorly understood. To address the impact of type I collagen on the fate of tumour cells, human breast carcinoma MCF-7 cells were cultured within three-dimensional type I collagen gels (3D COL1). Using this experimental model, we demonstrate that membrane type-1 matrix metalloproteinase (MT1-MMP), a proteinase overexpressed in many aggressive tumours, promotes tumour progression by circumventing the collagen-induced up-regulation of BIK, a pro-apoptotic tumour suppressor, and hence apoptosis. A transcriptomic analysis was performed to decipher the molecular mechanisms regulating 3D COL1-induced apoptosis in human breast cancer cells. Control and MT1-MMP expressing MCF-7 cells were cultured on two-dimensional plastic plates or within 3D COL1 and a global transcriptional time-course analysis was performed. Shifting the cells from plastic plates to 3D COL1 activated a complex reprogramming of genes implicated in various biological processes. Bioinformatic analysis revealed a 3D COL1-mediated alteration of key cellular functions including apoptosis, cell proliferation, RNA processing and cytoskeleton remodelling. By using a panel of pharmacological inhibitors, we identified discoidin domain receptor 1 (DDR1), a receptor tyrosine kinase specifically activated by collagen, as the initiator of 3D COL1-induced apoptosis. Our data support the concept that MT1-MMP contributes to the inactivation of the DDR1-BIK signalling axis through the cleavage of collagen fibres and/or the alteration of DDR1 receptor signalling unit, without triggering drastic alterations of the transcriptome of MCF-7 cells. [less ▲]

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See detailSystème d’exploitation et potentialités économiques des cuvettes oasiennes du sud-est du Niger
Malam Boukar, Awa Krou; Yamba, Boubacar; Lebailly, Philippe ULg

Poster (2016, September 28)

Les cuvettes oasiennes du sud-est nigérien sont sources de production alimentaire (JAHIEL. 1998). C’est pourquoi, les populations locales sont dépendantes des cuvettes pour leurs productions alimentaires ... [more ▼]

Les cuvettes oasiennes du sud-est nigérien sont sources de production alimentaire (JAHIEL. 1998). C’est pourquoi, les populations locales sont dépendantes des cuvettes pour leurs productions alimentaires et leurs revenus (TYCHON B. et al. 2009). Cette étude vise à démontrer l’importance socio-économique des cuvettes oasiennes du sud-est nigérien. [less ▲]

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See detailDEVELOPMENT OF NOVEL CATIONIC AND LIGAND-GRAFTED ANIONIC LIPOSOMES FOR BRAIN-TARGETED DRUG DELIVERY
Karim, Reatul ULg; Palazzo, Claudio ULg; Laloy, Julie et al

Poster (2016, September 27)

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See detailInfluence of groundwater exchanges on the efficiency of Underground Pumped Storage Hydroelectricity plants using open pit mines
Pujades, Estanislao ULg; Bodeux, Sarah ULg; Orban, Philippe ULg et al

Poster (2016, September 27)

Underground Pumped Storage Hydropower (UPSH) plants can be used to manage the production of electrical energy according to the demand. These plants consist in two reservoirs, the upper one is located at ... [more ▼]

Underground Pumped Storage Hydropower (UPSH) plants can be used to manage the production of electrical energy according to the demand. These plants consist in two reservoirs, the upper one is located at the surface while the lower one is underground. The energy is stored by pumping water from the lower to the upper reservoir and produced by releasing water from the upper to the lower one. As a result, the hydraulic head in the lower reservoir varies continuously. UPSH plants interact with the surrounding aquifers exchanging groundwater. These groundwater exchanges, which play an important role in the evolution of the hydraulic head inside the underground reservoir, are a fact of concern in the selection of pumps and turbines because their efficiency varies with respect to the head difference between the two reservoirs. Therefore, the aquifer parameters should be considered in the selection of pumps and turbines. In this context, with an UPSH plant made up by an open pit mine, we study numerically (1) the influence of groundwater exchanges on the efficiency and (2) how the hydraulic head evolution varies depending on the aquifer properties. The relation among the groundwater exchanges, the efficiency of pumps and turbines and the aquifer parameters is considered by comparing the numerical results of several simulations. It is shown that groundwater exchanges are not negligible when optimizing the efficiency of UPSH plants. A priori, low hydraulic conductivity geological media were preferred to decrease interactions with the open-pit or the cavity used as lower reservoir. Taking into account the pump/turbine performance curves, it appears that, on the contrary, the global efficiency would be increased if the surrounding medium facilitates large groundwater exchanges because hydraulic head variations are softened. [less ▲]

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See detailClimatic and management drivers of CO2 exchanges by a production crop: Analysis over three successive 4-year crop rotation cycles
Buysse, Pauline ULg; Manise, Tanguy ULg; De Ligne, Anne ULg et al

Poster (2016, September 27)

Carbon dioxide (CO2) exchanges between crops and the atmosphere are influenced by both climatic and crop management drivers. The investigated crop, situated at the Lonzée Terrestrial Observatory (LTO ... [more ▼]

Carbon dioxide (CO2) exchanges between crops and the atmosphere are influenced by both climatic and crop management drivers. The investigated crop, situated at the Lonzée Terrestrial Observatory (LTO, candidate ICOS site) in Belgium and managed for more than 70 years using conventional farming practices, was monitored over three complete sugar beet/winter wheat/potato/winter wheat rotation cycles from 2004 to 2016. Continuous eddy-covariance measurements and regular biomass samplings were performed in order to obtain the daily and seasonal Net Ecosystem Exchange (NEE), Gross Primary Productivity (GPP), Total Ecosystem Respiration (TER), Net Primary Productivity (NPP), and Net Biome Production (NBP). Meteorological data and crop management practices were also recorded. Over the 12 years, NEE was negative (-4.34 kg C m-2) but NBP was positive (1.05 kg C m-2), i.e. as soon as carbon exportation by harvest and carbon importation (manure, slimes) are included in the budget, the site behaves as a carbon source. At the crop rotation scale (4 years) it was quite remarkable to observe that NBP was very similar over the three rotations (0.30-0.36 kg C m-2), despite climatic and management differences between years. Crop type impacted carbon exchanges, with sugar beet and winter wheat crops leading to higher net carbon sequestration than seed potato crops. For one given crop, larger growth length and cumulated global radiation drove larger cumulated NEE. Net carbon emissions were observed during intercrops, but growing mustard during these periods reduced their rates and provided carbon residues to the soil. NBP values suggest that one sixth of the total soil organic carbon stock at LTO (6.23 ± 0.16 kg C m-2 in [0, 60] cm) would be lost in 12 years. Large uncertainties (mostly due to biomass measurements) affect NBP estimates, but still, this figure is huge and should encourage cultural practices returning carbon to the soil. [less ▲]

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See detailAssessing the impact of climate change on terrestrial plants in Europe using a Dynamic Vegetation Model driven by EURO-CORDEX projections
Dury, Marie ULg; Hambuckers, Alain ULg; Henrot, Alexandra-Jane ULg et al

Poster (2016, September 26)

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more ... [more ▼]

While the combination of warmer and drier mean climatic conditions can have severe impacts on ecosystems, extreme events like droughts or heat waves that break the gradual climate change can have more long-term consequences on ecosystem composition, functioning and carbon storage. Hence, it is essential to assess the changes in climate variability and the changes in frequency of extreme events projected for the future. Here, the process-based dynamic vegetation model CARAIB DVM was used to evaluate and analyse how future climate and extreme events will affect European terrestrial plants. To quantify the uncertainties in climatic projections and their potential impacts on ecosystems, the vegetation model was driven with the outputs of different regional climatic models, nested in CMIP5 GCM projections for the EURO-CORDEX project: ALADIN53 (Météo-France/CNRM), RACMO22E (KNMI), RCA4 (SMHI) and REMO2009 (MPI-CSC) RCMs. These daily climatic scenarios are at a high spatial resolution (0.11°, ≈ 12 km). CARAIB simulations were performed across Europe over the historical period 1971-2005 and the future period 2006-2100 under RCP4.5 and RCP8.5 emission scenarios. We simulated a set of 99 individual species (47 herbs, 12 shrubs and 40 trees) representing the major European ecosystem flora. First, we analysed the climatic variability simulated by the climatic models over the historical period and compared it with the observed climatic variability. Then, we evaluated change in climatic variability and extreme events projected by the climatic models for the end of the century. Finally, we assessed the change in species productivity and abundance. We evaluated the severity of projected productivity change for the period 2070-2099 relative to their current productivity variability (period 1970-1999). Mean changes were considered severe if they exceed observed variability. The projections of potential shifts in species distributions are directly dedicated to current forest management. [less ▲]

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See detailQuelles réponses face à la fatigue vocale? Variabilité inter-individuelle des modifications acoustiques de la voix au cours de la journée
Remacle, Angélique ULg; Gerber, Silvain; Garnier, Maëva

Poster (2016, September 26)

Objectifs: 1) décrire l’évolution de 4 indicateurs acoustiques de la fatigue vocale au cours d’une journée de travail et examiner leur universalité dans l'échantillon, 2) déterminer si différentes ... [more ▼]

Objectifs: 1) décrire l’évolution de 4 indicateurs acoustiques de la fatigue vocale au cours d’une journée de travail et examiner leur universalité dans l'échantillon, 2) déterminer si différentes typologies de réponse à la fatigue vocale peuvent être distinguées. Population: 22 enseignantes enregistrées le matin et le soir après leur journée de travail, à 3 temps de l’année: octobre, décembre, et février. Tâche: voyelle [a] tenue produite 5 fois à intensité et fréquence confortables. Paramètres mesurés avec Praat et moyennés sur les 5 répétitions: F0 (Hz), rapport harmoniques/bruit (HNR, dB), local Jitter (%), et local Shimmer (%). Les variations des moyennes entre le soir et le matin (Δ) sont calculées pour chaque paramètre. Résultats: En accord avec la littérature, le Δ moyen pour les 22 participantes aux 3 temps montre une augmentation de F0 et HNR, et une diminution de Jitter et Shimmer au cours de la journée. Cependant, ces résultats ne sont pas généralisés dans notre échantillon. Une analyse hiérarchique ascendante permet d'identifier 3 typologies de réponse à la fatigue vocale, observées suite à la journée de travail. Typologie 1: tendance inverse à la littérature (ΔF0 et ΔHNR négatifs, Δjitter et Δshimmer positifs). Comportement hypofonctionnel en réponse à la fatigue vocale. Typologie 2: tendance et amplitude similaires à la littérature (ΔF0 et ΔHNR positifs, Δjitter et Δshimmer négatifs). Réponse attendue, adaptation saine à la fatigue vocale. Typologie 3: tendance similaire à la littérature mais d’amplitude très marquée. Comportement hyperfonctionnel, suspicion d’un trouble vocal. [less ▲]

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See detailSmall molecule ligands for the orphan GPR27
Dupuis, Nadine ULg; Franssen, Delphine ULg; Laschet, Céline ULg et al

Poster (2016, September 26)

Background G protein-coupled receptors (GPCRs) are involved in many physiological processes and constitute the target of around 30% of marketed therapies. Nonetheless, ~100 human GPCRs have no known ... [more ▼]

Background G protein-coupled receptors (GPCRs) are involved in many physiological processes and constitute the target of around 30% of marketed therapies. Nonetheless, ~100 human GPCRs have no known ligand and are designated as "orphan". This project focuses on GPR27, a rhodopsin-like alpha orphan of the SREB family (Super conserved Receptors Expressed in the Brain), presumably involved in the regulation of insulin secretion [1]. Methods In order to identify small molecules activating GPR27, we developed a firefly luciferase complementation assay (based on [2]) to assess the binding of ß-arrestin2 to the activated GPCR. To increase the affinity for and strengthen the interaction with ß-arrestin2, a GPR27-V2R chimera has been used for library screening. Results Small molecules activating GPR27-V2 have been identified in the DiverSetTM library (ChemBridge). After exclusion of non-specific activities using another unrelated GPCR, two compounds sharing a common scaffold with activity in the low micromolar range were selected for further investigations. We confirmed their agonist profile by performing complete concentration-response curves on our arrestin complementation assay as well as orthogonal assays. These compounds show good specificity being inactive on GPR85-V2 and GPR173-V2 (the two other SREB members). With these original tools, we characterized the recruitment of ß-arrestin2 to activated GPR27 WT. Conclusion We identified small molecule ligands for GPR27 that will serve as valuable tools for studying the pharmacology of GPR27 as well as its physiological roles, for example in insulin secretion. 1 Ku G.M., Pappalardo Z., Luo C.C., German M.S., McManus M.T. An siRNA Screen in Pancreatic Beta Cells Reveals a Role for Gpr27 in Insulin Production. PLoS genetics. 2012, 8, e1002449. 2 Takakura H., Hattori M., Takeuchi M., Ozawa T. Visualization and Quantitative Analysis of G Protein-Coupled Receptor−β-Arrestin Interaction in Single Cells and Specific Organs of Living Mice Using Split Luciferase Complementation. ACS Chem. Biol. 2012, 7, 901−910. [less ▲]

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See detailMUCOADHESIVE SPONGES WITH PEGYLATED LIPOPLEXES: TOWARDS A SUSTAINED VAGINAL DELIVERY OF siRNA
Furst, Tania ULg; Dakwar, Georges; zagato, Elisa et al

Poster (2016, September 26)

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See detailGlucose production: influence of the datasets choice on LCA results
Gerbinet, Saïcha ULg; Belboom, Sandra ULg; Léonard, Angélique ULg

Poster (2016, September 22)

The aim of this study is to have a good understanding of the environmental impact of glucose production. Glucose is generally produced from corn or wheat. Since agricultural processes are known to be ... [more ▼]

The aim of this study is to have a good understanding of the environmental impact of glucose production. Glucose is generally produced from corn or wheat. Since agricultural processes are known to be difficult to evaluate by LCA, the results obtained with two different LCA databases, Gabi and EcoInvent, are compared in this work. The production of glucose from raw materials can be divided in two steps: the agricultural step allowing the plant production, and the conversion step including the extraction of the starch from the plant and its hydrolysis into glucose. Preliminary results underline the high impact of the agricultural step, so a special attention has been paid to these data. Specific Belgian data collected by the Walloon Agricultural Research Centre (CRA-W) (2014) [1] have been used as primary data (yield, amount of fertilizers, etc.), either using EcoInvent or Gabi datasets background data to model fertilizers, diesel consumption, etc. A third model was built using only data available in Ecoinvent for corn and wheat cultures. For the conversion step, literature data have been used along with some industrial data. As few studies are available in the literature concerning starch hydrolysis, the focus has been placed on data validation (mass balance checks, cross-reference information, etc.). Based on these multiple sources, it is possible to compare the LCA results for the production of 1 kg of glucose for three different cases, summarized in the following table. Table 1: Summary of modelled cases Agricultural step Conversion steps Primary data Dataset Primary data Dataset Case 1 Belgian GaBi Literature + Industry GaBi Case 2 Belgian Ecoinvent Literature + Industry Ecoinvent Case 2 Ecoinvent Literature + Industry Ecoinvent The results obtained using these three models will be presented, at both the inventory and impact assessment steps. They show significant differences and highlight the need to understand in depth the involved assumptions when developing the datasets, in addition to the ones adopted for the inventory. [less ▲]

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See detailValorization of Seeds from Some Field Border Flowering Seeds
Paul, Aman ULg; Danthine, Sabine ULg; Mutwale Kapepula, Paulin ULg et al

Poster (2016, September 20)

Flowering strips are now being increasingly cultivated along the fields to improve biodiversity. However after serving for the desired function, these plants have no utilization besides animal feed. It ... [more ▼]

Flowering strips are now being increasingly cultivated along the fields to improve biodiversity. However after serving for the desired function, these plants have no utilization besides animal feed. It could be really interesting to valorize some commonly grown plant in these strips to render food or health promoting compounds. With this objective in mind the seeds of Achillea millefolium, Anthriscus sylvestris and Prunella vulgaris were investigated for lipids, proteins and phenolic content. Further the lipids were analyzed for fatty acid profile using gas chromatography and the phenolic compounds in the methanolic extract of defatted seeds were identified using HPLC-DAD. The antiradical activity of the methanolic extracts obtained from defatted seeds was investigated using DPPH and ABTS assays. The anti-inflammatory potential of these seed extracts was evaluated on the reactive oxygen species (ROS) production by stimulated neutrophils and on the specific activity of myeloperoxidase (MPO), a pro-oxidant enzyme marker of inflammation. Seeds from all three plants were analyzed with interesting levels of lipids, proteins and phenolic content. Linoleic acid, oleic acid and alpha-linolenic acid were the major fatty acids analyzed in A. millefolium, A. sylvestris and P. vulgaris respectively. On the other hand different phenolic acid formed the major phenolic constituents. Seed extracts displayed high ABTS and DPPH radical-scavenging activities in a dose dependent manner. Also a strong dose dependent anti-inflammatory activity of all three extracts was observed against ROS production by neutrophils and MPO activity. Results indicate that these seed show a great potential to render lipids which could be utilized as human food, further the defatted seeds could be directly included in human diet due to interesting levels of proteins and anti-inflammation ability. [less ▲]

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See detailImpact du nombre d’alternatives lors d’une tâche de reconnaissance à choix-forcé sur les processus de reconnaissance dans le vieillissement normal
Simon, Jessica ULg; Gilsoul, Jessica ULg; Bastin, Christine ULg

Poster (2016, September 19)

Les tâches de reconnaissance à choix forcé sont classiquement utilisées pour évaluer la mémoire de reconnaissance. Cependant, aucune étude n’a spécifiquement investigué l’impact du nombre d’alternatives ... [more ▼]

Les tâches de reconnaissance à choix forcé sont classiquement utilisées pour évaluer la mémoire de reconnaissance. Cependant, aucune étude n’a spécifiquement investigué l’impact du nombre d’alternatives sur les performances mnésiques des participants âgés. Nous voulons déterminer, d’une part, si le nombre d’alternatives proposées - deux ou trois – et d’autre part, si le degré de similarité entre la cible et ses leurres ont un impact sur les stratégies de récupération mises en place au cours de la tâche. Pour ce faire, nous avons recruté 20 participants jeunes et 20 participants âgés. Lors de la tâche de reconnaissance, nous leur avons demandé de choisir, parmi deux ou trois photographies de visages, celui qui a été présenté précédemment. Certains couples cibles-leurres étaient plus similaires que d’autres (partage de 60% de caractéristiques communes, contre 40%). Pour chaque item sélectionné, les participants devaient expliquer ce qui a guidé leur choix. Les premières analyses (ANOVA à mesures répétées 2 (groupes) x 2 (alternatives) x 2 (similarité) sur les deux dernières mesures, p<0,05) montrent que les performances entre les groupes sont équivalentes pour la tâche de reconnaissance à deux alternatives. A l’inverse, nous avons observé que les participants jeunes avaient significativement de meilleures performances que les âgés dans la tâche de reconnaissance à trois alternatives. Les profils mnésiques des participants seront étudiés à la lumière des modèles à deux processus de la reconnaissance. Nous faisons l’hypothèse d’un recours plus fréquent à la recollection chez les jeunes dans la tâche de reconnaissance à trois alternatives (vs deux alternatives), alors que le choix de l’item se ferait chez les âgés, en comparant directement les degrés de familiarité associés à chaque item et en sélectionnant le plus familier (Norman & O’Reilly, 2003). [less ▲]

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See detailBeta cell regeneration from pancreatic ducts in adult zebrafish
Manfroid, Isabelle ULg

Poster (2016, September 18)

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See detailObjective drowsiness monitoring to assess fitness for duty
François, Clémentine ULg; Hoyoux, Thomas ULg; Langohr, Thomas ULg et al

Poster (2016, September 16)

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See detailOn-farm Evolution of Genetic Diversity of Four Old Varieties of Phaseolus vulgaris L.
Caproni, Leonardo; Raggi, Lorenzo; Klaedtke, Stephanie ULg et al

Poster (2016, September 16)

On-farm evolution of crop genetic diversity has a key role in adaptation of agricultural systems to changes. The aim of this work was to understand how four different old common bean varieties, which ... [more ▼]

On-farm evolution of crop genetic diversity has a key role in adaptation of agricultural systems to changes. The aim of this work was to understand how four different old common bean varieties, which being made of different genotypes can be referred to as populations, evolved on-farm during three years of multiplication (from 2012 to 2014) in two different experimental sites (Brittany and Luxembourg) under organic farming conditions. The four populations (Flageolet Chevrier Vert, Rognon de Coq, Roi des Belges, Saint Esprit à Œil Rouge) were chosen among those grown by two small-scale organic seed farmers while the commercial variety (Calima) was included as control. In 2015 the initial and the evolved populations were grown in a common field and characterized with morpho-phenological traits. In the same year, young leaf tissues were collected from 94 samples per population (total of 470 samples) for DNA extraction and molecular characterization. Genotyping was carried out using 22 SSR loci and fluorescent PCR amplicons analysed on an ABI3130xl sequencer. Molecular data were then used for multivariate analysis, analysis of molecular variance and pair-wise Fst statistics calculation. Genotyping resulted in the production of about 20K data points. A total of 83 different alleles were identified in 16 polymorphic loci ranging from two (BMb293, BM156, BMd-44) to 18 (BMd-43). The first two axis of the Principal Coordinates analysis (PCoA) explained 76,13% of total diversity and clearly distinguished the five groups of populations. Analysis of Molecular Variance (AMOVA) showed that 76, 20 and 4% of total diversity is among populations, individuals and within individuals, respectively. Only for multiplications carried out in Luxemburg significant differentiation between the original populations and final populations were found in two old varieties (Flageolet Chevrier Vert and Rognon de Coq, Fst = 0.117 and 0.143, respectively, P≤0.001). The results showed that in Luxemburg farmer practices and pedo-climatic conditions significantly shaped the diversity of the two populations. This is confirmed by phenotypic observations, as these multiplications also significantly differed (p<0.05) for flowering date for all varieties except 'Roi des Belges'. [less ▲]

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See detailMetabolites from media supplemented with 3’-sialyllactose and fermented by bifidobacteria have an antivirulent effect against intestinal pathogens
Bondue, Pauline ULg

Poster (2016, September 16)

Introduction Complex oligosaccharides from human milk (HMO) promote growth of bifidobacteria such as Bifidobacterium bifidum [1]. Whey, a by-product of dairy-industry, contents complex oligosaccharides ... [more ▼]

Introduction Complex oligosaccharides from human milk (HMO) promote growth of bifidobacteria such as Bifidobacterium bifidum [1]. Whey, a by-product of dairy-industry, contents complex oligosaccharides (BMO) similar to HMO, which are mainly represented in colostrum by 3’-sialyllactose (3’SL) [2]. Bifidobacterium crudilactis, a species of bovine origin, encodes for β galactosidases and α-glucosidases and could therefore be able to metabolise those BMO [3; 4; 5]. In addition, fermentation products from bifidobacteria can produce antivirulent activity against intestinal pathogenic bacteria [6; 7]. This study focused on capacity of bifidobacteria to metabolise BMO, more particularly 3’SL, and on potential antivirulent effect of cell-free spent media (CFSM) against virulence gene expression of pathogenic bacteria. Material and methods B. bifidum BBA1 and B. crudilactis FR/62/B/3 isolated respectively from breastfed children feces and from cow raw milk cheese were grown on media supplemented with BMO or 3’SL, as sole source of carbon. The CFSM were harvested after centrifugation of cells culture, freeze-dried and concentrated 10 fold. Next, their effects were tested against virulence gene expression using ler and hilA promoter activity of luminescent constructs of Escherichia coli 0157:H7 ATCC 43888 and Salmonella Typhimurium SA 941256, respectively. The effect was confirmed on wild type strains of E. coli O157:H7 ATCC 43890 and S. Typhimurium ATCC 14028 using RT-qPCR. Results Both strains were able to grow in presence of whey or 3’SL, but B. crudilactis showed the best growth compared to B. bifidum. The highest cell concentrations were observed with media containing whey (8.9 ± 0.6 log cfu/ml and 8.1 ± 0.3 log cfu/ml, respectively). CFSM from fermented media supplemented with 3’SL resulted in under-expression of hilA and ler genes for the luminescent constructs and in under-expression of ler (ratios of -15.4 and -8.1) and qseA (ratios of -2.1 and -3.1) genes for the wild type strain of E. coli O157:H7. No effect was observed for the wild type strain of S. Typhimurium. Discussion B. crudilactis presented the best growth potential probably because its genome encodes the enzymatic machinery to use BMO (β galactosidases and α-glucosidases) [3; 4; 5]. The positive effect of media supplemented with milk products on growth of probiotics has been demonstrated previously [8]. CFSM obtained from media supplemented with 3’SL down-regulate several virulence genes of E. coli O157:H7 and potentially S. Typhimurium. This effect has been observed previously with CFSM obtained from fermentation of lactic acid bacteria or bifidobacteria, by production of antivirulent metabolites [2; 3]. BMO combined with some bifidobacteria strains of bovine or human origin could therefore be an interesting synbiotic to maintain or restore the intestinal health of young children. These effects observed in vitro will be further investigated regarding the exact nature of the active molecules. References 1. Garrido D. et al. (2013). Microbiology 159: 649-664. 2. Urashima T. et al. (2013). Biosci Biotechnol Biochem 77: 455-466. 3. Sela D. A. (2011). Int J Food Microbiol 149: 58-64. 4. Milani C. et al. (2014). Appl Environ Microbiol 80: 6290-6302. 5. Bondue P. & Delcenserie V. (2015). Korean J Food Sci Anim Resour 35: 1-9. 6. Medellin-Pena M. J. et al. (2007). Appl Environ Microbiol 73: 4259-4267. 7. Bayoumi M. A. & Griffiths M. W. (2012). Int J Food Microbiol 156: 255-263. 8. Champagne C. P. et al. (2014). Can J Microbiol 60: 287-295. [less ▲]

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See detailCHARACTERISATION OF THE STRUCTURAL, DYNAMIC AND AGGREGATION PROPERTIES OF THE W64R AMYLOIDOGENIC MUTANT OF LYSOZYME
Vettore, Nicola; Kumita, Janet; Moray, Joël ULg et al

Poster (2016, September 15)

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See detailDevelopment of a semiochemical-based control method against the walnut husk fly, Rhagoletis completa Cresson
Sarles, Landry ULg; Lognay, Georges ULg; Verhaeghe, Agnès et al

Poster (2016, September 15)

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Peer Reviewed
See detailExtremophile plants as source of biopesticides against European damageable plant pathogens
Ben Kaab, Sofiène ULg; Parisi, Olivier ULg; De Clerck, Caroline ULg et al

Poster (2016, September 14)

The use of plant-derived products in postharvest disease management may be a valid alternative to conventional chemical treatments (Pane et al., 2016). Unfavorable environmental conditions (such as salt ... [more ▼]

The use of plant-derived products in postharvest disease management may be a valid alternative to conventional chemical treatments (Pane et al., 2016). Unfavorable environmental conditions (such as salt and drought) increase production and accumulation of reactive oxygen species (ROS). Consequently, extremophile plants have developed adaptive responses including the synthesis of specific bioactive molecules used for medical and nutritional purposes (Ksouri et al., 2012). In that context, the main objective of the present study was the identification of effective plant extracts and essential oils from extremophile plants against the most important plant pathogens in Europe (in term of loss, treatment necessity and/or cost). The study began with the selection of four endemic medicinal species suspected to be antimicrobial due to their wealth of phenolic and terpene compounds, such as flavonoids, phenolic acids, and coumarins (Ksouri et al., 2012). Each of the aerial plant materials was grounded and macerated with solvent (methanol or chloroform) for 24 h. The solvent was then eliminated along rotavapor. The yield of plant extract varied between 1.56 and 6.7%. Kinetics of growth of the 3 pathogens cultivable in liquid medium was determined before testing the impact of plant extracts and essential oils. Methanolic and chloroform plant extracts (EM1, EM2, EC1 and EC2) and essential oils (EO1, EO2) were compared for their antifungal potential. The chemical composition of the essential oils obtained by hydrodistillation from the aerial parts was analyzed by GC/MS. Yield of essential oil varied between 0.7 and 1.2%. Therefore, antifungal activity of plant extracts and essential oils was evaluated using ELISA microplates with a blocked randomized design, as described previously (Parisi et al., 2013). The results obtained showed that EM2 at 7 mg/ml has a very high fungistatic activity against Fusarium culmorum, F. oxysporum and Penicillium italicum. It was characterized with a high amount of polyphenols, flavonoids and condensed tannins. Statistical analysis showed that the efficiency of methanol extracts significantly differed from those of the chloroform extracts. In addition, essential oils significantly reduced spores germination in a dose-dependent manner. Their fungistatic activity reached 100% at 6000 ppm. In conclusion, this work allowed us to open new perspectives on the application of extremophile plant extracts as novel biocontrol strategy against plant pathogens. [less ▲]

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See detailEffects of seed traits variation on seedling performance of the invasive weed, Ambrosia artemisiifolia
Monty, Arnaud ULg; Mahy, Grégory ULg; Ortmans, William ULg

Poster (2016, September 14)

Seedling performance can determine the survival of a juvenile plant and impact adult plant performance. Understanding the factors that may impact seedling performance is thus critical, especially for ... [more ▼]

Seedling performance can determine the survival of a juvenile plant and impact adult plant performance. Understanding the factors that may impact seedling performance is thus critical, especially for annuals, opportunists or invasive plant species. Seedling performance can vary among mothers or populations in response to environmental conditions or under the influence of seed traits. However, very few studies have investigated seed traits variations and their consequences on seedling performance. Specifically, the following questions have been addressed by this work: 1) How the seed traits of the invasive Ambrosia artemisiifolia L. vary among mothers and populations, as well as along the latitude; 2) How do seed traits influence seedling performance; 3) Is the influence on seedlings temperature dependent. With seeds from nine Western Europe ruderal populations, seed traits that can influence seedling development were measured. The seeds were sown into growth chambers with warmer or colder temperature treatments. During seedling growth, performance-related traits were measured. A high variability in seed traits was highlighted. Variation was determined by the mother identity and population, but not latitude. Together, the temperature, population and the identity of the mother had an effect on seedling performance. Seed traits had a relative impact on seedling performance, but this did not appear to be temperature dependent. Seedling performance exhibited a strong plastic response to the temperature, was shaped by the identity of the mother and the population, and was influenced by a number of seed traits. [less ▲]

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See detailFirst come first served: “priority effect“ benefits Ambrosia artemisiifolia L. more than other ruderal Asteraceae species
Ortmans, William ULg; Mahy, Grégory ULg; Monty, Arnaud ULg

Poster (2016, September 14)

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of ... [more ▼]

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of central and southern France, and northern Italy. Northwards beyond the edge of this range, occurrence of casual population have been described for years, but these populations do not appear to become invasive, and the species does not seem to spread. This situation raises the following question: Has the invaded range reached a limit or will the species continue its invasion northwards? To answer this question, we followed two complementary approaches. First we set up an experimental garden in Belgium, 250 km north to the current invaded range, to see if the local climate allows the completion of the species reproduction cycle. Second, we performed an in situ measurement campaign in 12 population located beyond the edge, within the range but near the margin, and in the center of the invaded range. The aim of this campaign was to test whether the species had reduced plant performance towards range margins. The results showed that the species is able to establish populations with high growth rates in Belgium. Furthermore, the species expressed similar performance across the considered areas, even beyond the current invasion front. No evidence of processes constraining the invasion was found, which suggests a great potential for invasion north to the current invaded range. In this uncertain situation, awareness actions should be considered in the northern countries. [less ▲]

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See detailInvolvement of membrane remodelling induced by fatty acids in the regulation of the NLRP3 inflammasome activity in human macrophages
Gianfrancesco, Marco ULg; Dehairs, Jonas; Bloch, Katerzina et al

Poster (2016, September 12)

Detailed reference viewed: 23 (5 ULg)
See detailPolyphosphoester containing amphiphilic block copolymers as drug nanocarriers
Ergül, Zeynep ULg; Vanslambrouck, Stéphanie; Thiry, Justine ULg et al

Poster (2016, September 12)

The design of drug delivery systems often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, supramolecularly self-assembled ... [more ▼]

The design of drug delivery systems often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, supramolecularly self-assembled amphiphilic block copolymers into spherical micelles are appropriate carriers for poorly soluble drugs. In that framework, we have designed novel functional poly(ethylene oxide)-b-polyphosphoester amphiphilic block copolymers able to cross-linked under UV and degrade in response to a reduction of the pH from neutral conditions. Therefore, an unsaturated alkene side-chain was introduced on the cyclic phosphate monomer according to a one-step reaction followed by its organocatalyzed polymerization initiated by a poly(ethylene oxide) macroinitiator. After self-assembly into water, the micelles were cross-linked by UV irradiation. Then, these cross-linked micelles have been loaded by doxorubicin, i.e. a drug used in cancer therapy. We observed that the doxorubicin loading increased with the number of double bonds on the polyphosphate block of non-cross-linked micelles. This diblock amphiphilic copolymer bearing pendant unsaturations appears thus particularly promising candidate to build micellar drug delivery systems for intravenous injection. [less ▲]

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See detailOrganocobalt complexes as source of radicals for the controlled polymerization of unconjugated monomers
Demarteau, Jérémy ULg; Cordella, Daniela ULg; Kermagoret, Anthony et al

Poster (2016, September 12)

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See detailPAI Annual Meeting
Ouhib, Farid ULg; Aqil, Abdelhafid ULg; Dirani, Ali et al

Poster (2016, September 12)

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See detailSynthesis and characterizations of non-isocyanate polyurethane (NIPU) hydrogels
Gennen, Sandro ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

Poster (2016, September 12)

Polyurethane (PU) is on of the most used polymers for the preparation of hydrogels due to its good biocompatibility, biodegradation and excellent mechanical properties. PU hydrogels are found in lot of ... [more ▼]

Polyurethane (PU) is on of the most used polymers for the preparation of hydrogels due to its good biocompatibility, biodegradation and excellent mechanical properties. PU hydrogels are found in lot of applications such as wound dressing, soft contact lenses, drug delivery and scaffolds for tissue engineering. Classicaly, PU is produced by a step-growth polymerization between diols and diisocyanates. However, in order to avoid the use of harmful isocyanates compounds and because of regulations which tend to ban the use of isocyanates, we developed hydrogels based on a non-isocyanate polyurethane (NIPU) chemistry by valorizing CO2-sourced cyclic carbonates and amines. Precisely, NIPU hydrogels were prepared by a solvent-free copolymerization between bifunctional hydrophilic polyethylene glycol cyclic carbonates and diamines in presence of a triamine as a crosslinker, followed by a water swelling of the obtained cross-linked gel. Parameters such as the cross-linking ratio and diamine’s nature were optimized. Different clay contents (cloiste 30B) as nanofiller were dispersed in the ideal cyclic carbonate/diamine/triamine formulation prior polymerization in order to reinforce the compression properties of NIPU hydrogels. Finaly, we were able to prepare NIPU hydrogels with water content up to 80 % and good compression properties using low clay content. [less ▲]

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See detailc-Jun regulates altered pre-mRNA splicing in response to cisplatin
Deward, Adeline; Gabriel, Maude; Klinck, Roscoe et al

Poster (2016, September 11)

Genotoxic stress is a well-known inducer of pre-mRNa alternative splicing . In this work, we aim at identifying keys componants of the signaling cascade linking the DNA lesion to the splcing machiney.and ... [more ▼]

Genotoxic stress is a well-known inducer of pre-mRNa alternative splicing . In this work, we aim at identifying keys componants of the signaling cascade linking the DNA lesion to the splcing machiney.and thus gain better knowledge od the molecular mechanism controling large scale splcing decision in stress situation. Nous avons établi que C-Jun est important pour l'épissage alternatif de nombreux ARN pré-messagers. [less ▲]

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Peer Reviewed
See detailSelf-defining memories and future projections as a means to facilitate reflection on life values in depressed adults: A preliminary study
Wagener, Aurélie ULg; Brouette, Béatrice ULg; Blairy, Sylvie ULg

Poster (2016, September 10)

Introduction. In the Brief Behavioral Activation Treatment for Depression, depressed patients are lead to a reflection on their personal values per life domains (e.g., family relationships, employment ... [more ▼]

Introduction. In the Brief Behavioral Activation Treatment for Depression, depressed patients are lead to a reflection on their personal values per life domains (e.g., family relationships, employment). The aim of this reflection is to tailor behavioral assignments through valued activities. This reflection is usually difficult for depressed patients. The current study hypothesized that exercises on autobiographical memories might act as a means to facilitate the reflection on personal values. In this perspective, self-defining memories (SDMs) and self-defining future projections (SDFPs) appear to be particularly relevant. SDMs and SDFPs concern reflections on the past and on the potential future central goals, values and conflicts of one’s life. SDMs and SDFPs are vivid and well-rehearsed autobiographical memories related to a meaning-making (i.e., a learned lesson about oneself, others or the world). The emotional valence of SDMs and SDFPs can either be positive, neutral or negative. Further, SDMs and SDFPs can consist in either specific events or categorical ones. Due to the relevance of these memories for the self, it is to be expected that recalling SDMs and imagine SDFPs will help individuals to have a clearer view of their personal values which in turn might facilitate the selection of valued activities. Further, it is hypothesized that these exercises might decrease depression and disturbances of psychological processes (i.e., rumination, self-concept clarity, environmental satisfaction). Therefore, this study aims were two-fold. First, it aimed at assessing the feasibility for depressed patients to recall SDMs and to imagine SDFPs per life domains. Second, it aimed at assessing the impact of these exercises on depression and psychological processes. Method. Nineteen depressed patients and 17 paired healthy controls (25-60 years) were recruited (data collection is still ongoing). This study comprises four meetings. During the first and the last meetings, participants completed self-reported assessments of depression and psychological processes. During the third and fourth meetings, participants were asked either to recall SDMs or to imagine SDFPs per life domains. SDMs and SDFPs were rated on specificity, meaning-making and emotional. The impact of these exercises was assessed on depression and psychological processes. Results. Preliminary results indicate that depressed patients are as able as healthy controls to recall SDMs and imagine SDFPs per life domains. Depressed patients recall less SDMs and SDFPs with meaning-making than healthy controls. Depressed patients report less SDMs and less SDFPs related to employment and less SDMs related to hobbies than healthy controls. Preliminary results show a decrease of depression in depressed patients only. Discussion. Even though depressed patients are as able as the healthy controls to recall SDMs and to imagine SDFPs, preliminary results highlight significant differences between depressed patients and healthy controls on SDMs and SDFPs. Preliminary results indicate that SDMs and SDFPs positively impact depression in depressed patients. Experimental and clinical implications of these findings will be discussed during the conference. [less ▲]

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See detailInvolvement of Ikbζ in glioblastomas and its potential implication in radioresistance
Dubois, Nadège; Willems, Marie; Kroonen, Jérôme et al

Poster (2016, September 09)

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See detailCyanobacterial Diversity In Antarctic Aquatic Microbial Mats
Stelmach Pessi, Igor ULg; Lara, Yannick ULg; Durieu, Benoit ULg et al

Poster (2016, September 08)

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See detailWhy a culture collection of Cyanobacteria?
Wilmotte, Annick ULg; Renard, Marine ULg; Simons, Véronique

Poster (2016, September 08)

The BCCM/ULC public collection is funded by the Belgian Science Policy Office since 2011 and an ISO9001 certificate was obtained for the public deposition and distribution of strains, as part of the multi ... [more ▼]

The BCCM/ULC public collection is funded by the Belgian Science Policy Office since 2011 and an ISO9001 certificate was obtained for the public deposition and distribution of strains, as part of the multi-site certification for the BCCM consortium. The collection aims to gather a representative portion of the polar cyanobacterial diversity with different ecological origins (limnetic mats, soil crusts, cryoconites, endoliths…) and make it available for researchers to study the taxonomy, evolution, adaptations to harsh environmental conditions, and genomic make-up. It presently includes 226 cyanobacterial strains, with 120 being of (Sub) Antarctic origin (http://bccm.belspo.be/catalogues/ulc-catalogue-search). The morphological identification shows that the strains belong to the orders of Synechococcales, Oscillatoriales, Pleurocapsales, Chroococcidiopsidales and Nostocales. Continuous maintenance of living cultures, some of which are also cryopreserved, ensure the preservation and the possibility to rapidly deliver strains to clients for fundamental and applied research. [less ▲]

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See detailMagnetic shielding above 1 T at 20 K with bulk, large grain YBCO tubes made by Buffer-aided Top Seeded Melt Growth.
Wera, Laurent ULg; Fagnard, Jean-François ULg; Kumar, Nambury Devendra et al

Poster (2016, September 07)

A superconducting tube can be used as an efficient magnetic shield. The best shielding performance levels are usually achieved when the tube is closed at one or both extremities. The purpose of the ... [more ▼]

A superconducting tube can be used as an efficient magnetic shield. The best shielding performance levels are usually achieved when the tube is closed at one or both extremities. The purpose of the present work is to study experimentally the shielding performance of YBCO tubes obtained by Buffer-aided Top Seeded Melt Growth fabrication process (BA-TSMG). This fabrication process enables the tube to be closed at one extremity by a cap containing the seed and there is no air gap between the cap and the tube. The shielding effectiveness is characterized by two parameters: (i) the shielding factor, defined as the ratio between the applied magnetic induction and the local magnetic induction measured inside the shield, and (ii) the threshold induction, i.e. the applied magnetic induction above which a given value of the shielding factor cannot be achieved. The magnetic shielding performances of tubes with different geometry are characterized at 77 K in liquid nitrogen. Further magnetic shielding measurements are carried out on one tube at various temperatures ranging from 20 K to 77 K using a Physical Property Measurement System (PPMS). The tubes are subjected to a quasi-static (“DC”) uniform magnetic field. A Hall probe measures the axial component of the local magnetic induction along the axis of the tube as a function of the applied magnetic induction. In order to investigate how the cap prevents the magnetic flux from penetrating inside the tube, we also characterize open tubes where the cap is removed and compare their properties to those of closed tubes. Magnetic shielding measurements show that the threshold induction increases by a factor of 9 as temperature decreases from 77 K to 20 K. Measurements also show that the presence of the cap improves the shielding performance at the closed extremity of the order of 1000 as it reduces the penetration through the open end. Near the closed extremity, a threshold induction of 1.5 T was reached at 20 K. To our knowledge this threshold induction is the best value reported so far at 20 K, and is comparable in magnitude to the record threshold inductions reported for bulk MgB2 and Bi-2212 materials at lower temperatures. These results give evidence that efficient magnetic shields can be obtained with this fabrication technique. [less ▲]

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Peer Reviewed
See detailHow do droplets form?
Van Loo, Stéphanie ULg; Stoukatch, Serguei ULg; Kraft, Michael ULg et al

Poster (2016, September 07)

In microfluidics, flow focusing is widely used to produce water-in-oil droplets in microchannels at high frequency. We here report an experimental study of droplet formation in a microfluidic cross ... [more ▼]

In microfluidics, flow focusing is widely used to produce water-in-oil droplets in microchannels at high frequency. We here report an experimental study of droplet formation in a microfluidic cross-junction with a minimum number of geometrical parameters. We mostly focus on the squeezing regime, which is com- posed of two distinct steps : filling and pinching. The duration of each step (and corresponding volumes of each liquid phase) are analyzed. They vary according to both water and oil flow rates. These variations provide several insights about the fluid flows in both phases. We propose several scaling laws to relate the droplet volume and frequency to the flow rate of both phases. We also discuss the influence of surfactant and channel compliance on droplet formation. [less ▲]

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See detailAre Christmas tree plantations a suitable habitat for farmland birds?
Gailly, Robin ULg; Paquet, Jean-Yves; Titeux, Nicolas et al

Poster (2016, September 06)

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may ... [more ▼]

Over the last decade, nonfood perennial crops have been increasingly prevalent in European farming systems. Here, vegetation structure and crop management greatly differ from conventional crops and may likely impact farmland birds. Impacts on birds have been examined for bioenergy agricultural systems, such as miscanthus plantations and short rotation willow coppice. In Europe, the extend of Christmas tree plantations (CTP) has recently increased dramatically in farmland but their impacts on farmland birds remains largely unknown. We examined the extent to which CTP in southern Belgium alter bird species assemblages compared to traditional farmland. The presence and abundance of birds were recorded twice during a breeding season in randomly selected sites located in farmland areas with and without CTP. Results show that the conversion of traditional farmland into CTP modifies bird species assemblages and locally increases bird diversity and density without inducing biotic homogenization. This observed pattern indicates that CTP might constitute an interesting alternative habitat for farmland birds. However bird presence or abundance may be confounding indicator of habitat quality because individuals may be attracted to low-quality habitats in human modified landscapes. The European Stonechat Saxicola rubicola was chosen as a model species to investigate the quality of CTP as a breeding habitat in more details. Habitat quality in CTP was assessed with measures of reproductive success and survival. These measures were compared with those collected in traditional farmland. Although vegetation structure, field management and nest placement are highly different between habitat types, our first results suggest that CTP are not of lesser quality than traditional farmland for the European Stonechat. [less ▲]

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See detailContribution of Cross-linking and Ion-mobility for the study of protein and complex structures
Baumans, France ULg; Grifnée, Elodie ULg; Hage, Christoph et al

Poster (2016, September 05)

The tridimensional structures of proteins and the mapping of protein-protein interactions are precious sources of information for the understanding of their function. Different techniques such as X-ray ... [more ▼]

The tridimensional structures of proteins and the mapping of protein-protein interactions are precious sources of information for the understanding of their function. Different techniques such as X-ray cristallography or nuclear magnetic resonance are usually used to achieve this goal. In the field of mass spectrometry, several tools were also developped. The one presented here is the chemical cross-linking in which two reactive residue side chains, spatially close, are linked thanks to a bifunctional chemical, called crosslinker. Ion-mobility coupled to mass spectrometry has also been investigated for the study of cross-linked products. The first results tend to show that cross-linkers allow to fix the shape of the protein in solution, leaving it intact when analysed in the gas phase. [less ▲]

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Peer Reviewed
See detailIntegrated Project with Focus on Energy Transition and Circular Economy for Developing Engineering Students' Soft Skills
Léonard, Grégoire ULg; Pfennig, Andreas ULg; Toye, Dominique ULg et al

Poster (2016, September 05)

The present work reports the experience of an integrated project developed at the University of Liege for master students in chemical engineering. The goals are to promote the acquisition of soft skills ... [more ▼]

The present work reports the experience of an integrated project developed at the University of Liege for master students in chemical engineering. The goals are to promote the acquisition of soft skills and to consolidate technical knowledge by integrating and linking chemical engineering disciplines usually taught separately. A case study was selected to address some of the challenges related to energy transition: students had to design the energy system of a remote island and make it as energy independent and CO2-neutral as possible by 2030. The course of action during the academic year, the assessment of soft skills, and the tools offered to ease the mentoring and encourage the acquisition of soft skills are described. Not all implemented techniques performed equally well, and this project finally appeared to be a challenge for the teaching team as well. 1 Introduction and background Over the last few years, University authorities, industrial partners as well as national and international experts that evaluated the education quality of our Department (AEQES, CTI) strongly suggested that opportunities should be offered to students to increase their soft skills as part of their curriculum. Moreover, many developments in chemical engineering are related to energy transition and circular economy, which are both transdisciplinary to conventional lectures. In this paper, we present methods and mentoring tools developed to teach students technical and soft skills for multi-disciplinary topics. 2 Description of the integrated project Objectives and constraints were defined at the onset of the project for both technical and soft skills. The technical objective was to propose an energy system that would make Reunion Island as energy independent and CO2-neutral as possible by 2030. This idea originated in the challenge set by the Eurecha 2015 student contest[1], for which students had to design facilities for a sheikhdom: electricity, water recycling, production of fertilizers… In our case, Reunion Island (~850 000 inhabitants) was considered as a case study as it is remote, has large biomass resources and high potential for renewable energies. Besides the objectives mentioned above and in order to force students to look at chemical engineering processes, the treatment of wastewater was imposed as well as the use of a synthetic liquid fuel as energy carrier. The targeted soft skills included working in large groups of minimum 4 students, efficient communication of results in English - both written and oral -, ability to integrate knowledge from various disciplines, development of critical mind and demonstration of independent and creative thinking. 3 Course of actions A team of 8 professors and senior scientists mentored the project and contributed to its assessment. The 10-ECTS project was divided in two parts. In the fall semester, students made global energy balances to design the energy system that would fulfill the objectives. As a result, a Sankey diagram of the energy flows on Reunion Island by 2030 was produced to allow for an overview of the available Island’s resources and needs, as well as of processes that can make the link between resources and needs. In the spring semester, two processes identified in the first part, namely the synthesis of bio-ethanol and bio-methanol, were modelled in more details using commercial software. Different tools were used to encourage student initiatives and work: • The use of a shared on-line portfolio for students to gather their documents improved their internal communication, but this remained a marginal channel for communication with teachers • In the fall semester, students orally presented progress reports every two weeks. After a feedback to students, the teaching team met to discuss the achievements and set the objectives for the next two weeks. This was very positive for the communication inside the teaching team. However, presentations every fortnight implied a work overload for students that had to constantly focus on preparing the presentations. • From the beginning, students were strongly encouraged to reach out to field experts whose contacts were provided. However, they preferred to rely mostly on Internet as their main source of information and reached out only rarely for help and usually very late. • In the fall semester, students had to designate new team leaders in turn every fortnight. This was abandoned as it prevented the establishment of clear structures in the group, reducing its efficiency. • In the spring semester, work tables allowed students to work directly with the teacher specialized in their task. This was appreciated by students and teachers, and it needs to be further encouraged. • Help in the group organization and interactions was provided by the PSGO (psychology of groups and organizations). This also included videoscopy, i.e. filming the students during their presentations and analyzing the records with them. This help was appreciated by students. The assessment was based on technical results for 60%, and soft skills for 40%. The evaluation of technical skills was done partly by all teachers equally and partly by teachers whose expertise was the closest to the technical sub-tasks. For soft skills, efficient communication, creativity in the work and results and links with conventional lectures were assessed. Critical thinking was evaluated through the relevance of qualitative and quantitative results and discussions. Group work was assessed by the teachers as well as by students through mutual evaluation. 4 Conclusions and perspectives The integrated project gave students a first opportunity to improve their soft skills along with their technical knowledge. It also improved their communication skills and their fluency in English. The teaching team proposed different mentoring techniques to encourage efficient work, with varying results. Finally, as the assessment ignored soft skills improvements, it may be modified by evaluating soft skills all year long so both the final result and the observed improvements contribute to the grade. Reference Eurecha, The European Committee for the Use of Computers in Chemical Engineering Education, 2015. Announcement for student contest problem competition 2015. http://bari.upc.es/eurecha/. [less ▲]

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See detailFeeding ecology of Southern Ocean seastars inferred from stable isotopes ratios
Le Bourg, Baptiste ULg; Blanchard, Alice; Danis, Bruno et al

Poster (2016, September 05)

The Southern Ocean is currently subjected to strong and contrasted impacts of climate change. The Western Antarctic Peninsula is one of the most rapidly warming regions of the world, resulting in sea ice ... [more ▼]

The Southern Ocean is currently subjected to strong and contrasted impacts of climate change. The Western Antarctic Peninsula is one of the most rapidly warming regions of the world, resulting in sea ice cover decreases. Increasing seawater temperature and sea ice cover reduction in Western Antarctic Peninsula and associated regions will likely impact food web functioning through temperature-related changes in consumer physiology, modifications of benthic community structure (e.g. expansion of exogenous species such as predatory crabs), modifications of benthic-pelagic coupling intensity or disruption of benthic production. Asteroids (Echinoderms) are an important group of southern benthos. This group also has a great trophic variability and is potentially more resistant than other organisms to temperature changes (Peck et al. 2008). Consequently, they will be likely impacted by modifications in food webs functioning rather by direct warming and investigating their trophic ecology is necessary to infer how climate change will impact them. In this context, the aim of this study is to use stable isotopes ratios of C, N and S to infer sea stars trophic ecology. 16 species of sea stars spanning 10 different families sampled in multiple and contrasted habitats across Subantarctic (South Georgia, South Sandwich Islands, Falkland Islands) and Antarctic (South Shetland Islands, South Orkney Islands, Western Antarctic Peninsula) locations. In total, tegument samples from 213 specimens was analysed. Diversity and plasticity of asteroid diet along Southern Ocean coasts were explored through isotopic niche parametrisation (e.g. niche width and overlap between species and/or populations; Jackson et al. 2011). The data will also be used in a larger scale research project on the trophic ecology of Antarctic sea stars. This project will notably compare trophic resources supporting asteroid communities in Western Antarctic Peninsula, where sea ice cover is decreasing, and in Terre Adélie, where sea ice cover is increasing (Parkinson & Cavalieri 2012). Ultimately, this project will help understanding which ecological processes determine how an animal group copes with environmental modifications linked to climate change. [less ▲]

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See detailUnusually high sea ice cover influences resource use by benthic invertebrates in coastal Antarctica
Michel, Loïc ULg; Dubois, Philippe; Eleaume, Marc et al

Poster (2016, September 05)

Antarctica currently undergoes strong and contrasted impacts linked with climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice ... [more ▼]

Antarctica currently undergoes strong and contrasted impacts linked with climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice cover decrease, the sea ice cover of East Antarctica unexpectedly tends to increase, possibly in relation with changes in atmospheric circulation. Changes in sea ice cover are likely to influence benthic food web structure through modifications of benthic-pelagic coupling, disruption of benthic production and/or modifications of benthic community structure (i.e. resource availability for benthic consumers). Here, we studied shallow (0-20 m) benthic food web structure on the coasts of Petrels Island (Adélie Land, East Antarctica) during an event of unusually high spatial and temporal (two successive austral summers without seasonal break-up) sea ice cover. Using stable isotope ratios of C and N and the SIAR mixing model, we examined importance of 4 organic matter sources (benthic macroalgae, benthic biofilm, sympagic algae, suspended particulate organic matter) for nutrition of dominant primary consumers and omnivores. 14 invertebrate taxa including sessile and mobile polychaetes, gastropods, bivalves, sea stars, sea urchins and sea cucumbers were studied. Our results indicate that most benthic invertebrates predominantly relied on sympagic algae. Despite its very high abundance, trophic role of benthic biofilm seemed limited. However, interpretation of data was complicated by the peculiar ecophysiological features of Antarctic invertebrates, whose very low metabolic rates could be associated to low isotopic turnover and long time to reach isotopic equilibrium with their food items. Resource use by consumers from Adélie Land markedly differed from literature data about invertebrate diet in coastal Antarctica, suggesting 1) important influence of increased sea ice cover on benthic food web structure and 2) high spatial and/or temporal variation in the feeding habits of studied organisms, likely linked with a high degree of trophic plasticity. Our results provide insights about how Antarctic benthic consumers, which have evolved in an extremely stable environment, might adapt their feeding habits in response to sudden man-driven changes in environmental conditions and trophic resource availability. [less ▲]

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See detailBack on Track... in 3D
Marchal, Antoine ULg; Lejeune, Philippe ULg; De Bruyn, Nico

Poster (2016, September 04)

Ecological monitoring provides basic information on population status and distribution that is crucial for conservation, research and management strategies. Studies using tracks are controversial due to ... [more ▼]

Ecological monitoring provides basic information on population status and distribution that is crucial for conservation, research and management strategies. Studies using tracks are controversial due to past misuses tainted with subjectivity. Advances in photogrammetry literally add another dimension to the recording techniques, and geometric morphometrics provides an appropriate approach for the study of track shape variation. Tracks are back on track in conservation! [less ▲]

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See detailComputed tomographic findings of a far lateral lumbar disc extrusion in a dog
Rizza, Maïlis ULg; Bouvy, Bernard ULg; Shimizu, Naomi ULg et al

Poster (2016, September 01)

Introduction In human medicine, far lateral lumbar disc extrusion (FLLDE) represents 7 to 12% of all disc herniations and MRI is the method of choice for diagnosis. MRI findings of a FLLDE has been ... [more ▼]

Introduction In human medicine, far lateral lumbar disc extrusion (FLLDE) represents 7 to 12% of all disc herniations and MRI is the method of choice for diagnosis. MRI findings of a FLLDE has been reported in one dog and the aim of this case report is to describe computed tomographic (CT) findings of a FLLDE in a dog. Methods A six-year-old neutered female Beagle with a good general health status was presented with a month history of left hind limb pain with shivering of this limb. Clinical examination revealed a left hind proprioceptive deficit but no pain was elicited at palpation. Results A CT scan pre- and post- contrast studies of the lumbosacral spine and a myelographic-CT were performed. A 1.3x0.6x0.3 cm homogeneous hyperattenuating (+/- 350 HU) ovoid structure was observed at the left lateral aspect of L6-L7 intervertebral disc space. The L6-L7 intervertebral disc nucleus pulposus was calcified but the annulus fibrosus had a normal non-calcified attenuation and seemed intact apart from a very thin hyperattenuating line next to the ovoid structure. This change was well circumscribed by an even hyperattenuating rim (1000HU) mimicking a thin dense cortex and was in close proximity with the annulus fibrosus and the left transverse process of L7. Perineural fat was not observed and contrast enhancement was visualized at the level of the left sixth lumbar nerve root with impingement and thickening of this root. No compression of the spinal cord was observed at this level on the myeloCT. These findings were suggestive of a dystrophic mineralization or an osteochondromatosis. FLLDE was considered less likely because of the almost normal appearance of the annulus fibrosus. At surgery some mixed gelified calcified material consistent with disc material was removed at the level of the left L6-L7 nerve root tract and disc fenestration was performed. The histological analysis confirmed the presence of degenerated herniated vertebral disk. Discussion/Conclusions In human medicine, MRI and CT scan are the main diagnostic modalities employed for diagnosis of FLLDE. In veterinary medicine, CT is often used to assess spinal diseases because of its availability. To the authors’ knowledge, CT findings of a FLLDE have not been described previously in dogs. Moreover, the thin dense cortex appearance surrounding the disc material was surprising. In conclusion, FLLDE should be included in the differential diagnosis of a calcified ovoid structure lateral to the spine even if the annulus fibrosus appears normal and if this structure is in close relation with the vertebral transverse process. [less ▲]

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See detailComputed tomography-guided injection of muscle-derived mesenchimal stem cells in the intervertebral disc of dogs affected by natural disc degeneration: clinical safety and intervertebral disc imaging assessment
Liotta, Annalisa Pia ULg; Sandersen, Charlotte ULg; Ceusters, Justine ULg et al

Poster (2016, September 01)

Introduction/Purpose: Pre-clinical randomized controlled animal trials have been conducted to evaluate the effects of mesenchymal stem cell (MSCs) transplantation on intervertebral disc (IVD) degeneration ... [more ▼]

Introduction/Purpose: Pre-clinical randomized controlled animal trials have been conducted to evaluate the effects of mesenchymal stem cell (MSCs) transplantation on intervertebral disc (IVD) degeneration. According to their histological results and to imaging assessment of the IVD, intradiscal injection of MSCs is effective, arresting or slowing IVDD process, and is associated with a low complication rate. Few of these studies have been conducted on canine artificially degenerated IVD, using bone marrow or adipose-derived MSCs. Therefore a systematic study on naturally degenerated IVD using MSCs obtained from autologous muscular tissue in dogs is still lacking. The aims of this study were to evaluate the clinical effects of intradiscal injection of muscle-derived MSCs and its effects on imaging features of the intervertebral disc. Methods: Eight experimental dogs were randomly included with the approval of the University’s Animal Care and Use Committee. The final inclusion criteria were the presence of naturally degenerated lumbosacral IVD detected on low-field magnetic resonance (MRI) images and the obtaining of 3 x 106 autologous muscle-derived MSCs. A computed tomography (CT) and MRI examination was performed before and 2 months after the procedure and 13 imaging parameters were assessed. Mesenchymal stem cells diluted in 0,2 ml of FRS Hypothermosol were injected in the lumbosacral IVD under CT-guidance. Clinical examinations were performed regularly during 1 month after the procedure. Results: Six dogs met the inclusion criteria. The remaining 2 dogs did not undergo intradiscal injections, but were used as control group. No major or minor complications were reported during the procedure. No abnormalities were noticed during the clinical examinations. No statistically significant variations of IVD imaging features were noticed before and after the injections. Discussion/Conclusions: Intradiscal injection of muscle-derived MSCs is clinically safe and it is not associated with any progression of the IVD degeneration, detected by CT or low-field MRI imaging. Further studies are needed to assess its efficacy as treatment for the canine natural IVD degeneration. [less ▲]

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See detailVisuo-spatial STM impairment link to a serial order component deficit in children with Velocardiofacial syndrome
Attout, Lucie ULg; Vossius, Line ULg; Noël, Marie-Pascale et al

Poster (2016, September 01)

Some previous studies showed that verbal short-term memory (STM) is better preserved than visuospatial STM in the velocardiofacial syndrome (VCFS), a neurodevelopmental disorder resulting from a 22q11.2 ... [more ▼]

Some previous studies showed that verbal short-term memory (STM) is better preserved than visuospatial STM in the velocardiofacial syndrome (VCFS), a neurodevelopmental disorder resulting from a 22q11.2 deletion. This deficit is generally assigned to a more global visuospatial skills deficit. However, for verbal STM, previous study suggested a specific deficit in the serial order component, processing considered as independent of modalities. In this study we proposed to explore the serial order component in visuospatial STM by contrasting simultaneous vs. sequential presentation of stimuli to maintain in children with VCFS, in order to see in what extent the deficit is global and resulting from visuospatial deficit or whether this deficit is specific to the serial order component. We tested a group of 27 children and adolescents with VCFS to a control group, matched on verbal IQ performance estimated. The VCFS group showed impaired performance on the sequential configuration but similar performance on the simultaneous condition. These results support the idea of an amodal serial order component in STM. The implication of serial order STM deficits on numerical cognition will be discussed. [less ▲]

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See detailTEACHING VETERINARY RADIOLOGY: DOES COMPARISON HELP?
Etienne, Anne-Laure ULg; Delguste, Catherine ULg; Busoni, Valeria ULg

Poster (2016, September 01)

Introduction/Purpose Comparison learning is an approach for learning complex visual tasks. As described in human medicine, by comparing radiographs with pathology and without pathology, veterinary ... [more ▼]

Introduction/Purpose Comparison learning is an approach for learning complex visual tasks. As described in human medicine, by comparing radiographs with pathology and without pathology, veterinary students could learn to discriminate relevant disease-related information to recognize the disease. We hypothesized that exposure to a training by side-by-side comparison of normal to abnormal radiographs would lead to higher visual diagnostic accuracy and possibly to a higher ability to describe the features of a known disease on canine thoracic radiographs. Material and methods Twenty veterinary students were randomly assigned to either a group that compared radiographs showing thoracic disease with normal images (group 1) or to a group that only studied abnormal radiographs (group 2). All students had their theoretical radiology teaching and 13 of them had also received the practical teaching of the study curriculum, evenly distributed between the 2 groups. Twenty-nine radiographs of small animal thorax were used. The procedure consisted in three experimenter-supervised phases: 1. training, 2. visual recognition test, 3. feature description test. In the training phase, each screen showed two radiographs with the name of the disease present in each. In the group 1 (pathology/normal condition), a radiograph of a patient and a normal image were shown next to each other. In the group 2 (pathology/pathology condition), two radiographs of patients with the same disease were shown next to each other. The 9 screens were presented twice, with the diseases in a different order for the first and second runs. A Mann-Whitney test was used to compare the success rates of groups of students. Results On visual recognition test, there was no statistical difference in visual diagnostic accuracy between groups. When students gave the wrong answer, they often diagnosed the item as another disease of similar distribution (diffuse or focal). Students who received the practical teaching and students of group 1 had a higher accuracy for normal thoracic radiographs. On feature description test, no significant effect of comparison learning was found, but focal diseases were better described than diffuse diseases with a significant difference between these. Discussion/Conclusions Results show that comparison with normal images did not help in recognizing or describing thoracic pathologies but helps to recognize normal images. [less ▲]

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See detailSIMULATION AND ANALYSIS OF RECEPTOR DYNAMICS IN A BMP REGULATORY NETWORK
Germain, Morgan ULg; Bolander, Johanna; Ji, Wei et al

Poster (2016, September)

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See detailUse of NIR hyperspectral imaging to detect and quantify nodules on root system of associated crops
Eylenbosch, Damien ULg; Pierreux, Jérome ULg; Fernández Pierna, Juan Antonio et al

Poster (2016, September)

Winter wheat and peas cultivated in association and harvested when grains are dry show promising results in temperate areas. This association reach a good land equivalent ratio, reduce the nitrogen ... [more ▼]

Winter wheat and peas cultivated in association and harvested when grains are dry show promising results in temperate areas. This association reach a good land equivalent ratio, reduce the nitrogen fertilizer needs and obtain high quality harvest. These results are probably explained by the transfer of nitrogen from peas nodules to wheat roots. To test this hypothesis, quantification of nodules is required. Visual counting of nodules is time consuming and discrimination between the two kinds of roots is almost impossible. A new method is therefore needed. Near infrared hyperspectral imaging (NIR-HIS) was tested as a rapid method to quantify the amount of nodules and roots of each species in soil samples. [less ▲]

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See detailInvestigation of the coagulation system in canine idiopathic pulmonary fibrosis
Roels, Elodie ULg; Bauer, N.; Lecut, Ch. et al

Poster (2016, September)

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See detailRadioscopy laboratory diagnostic of epizootic diseases in Belgium and European countries
Cargnel, Mickaël ULg; Roelandt, Sophie; Van der Stede, Yves et al

Poster (2016, September)

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See detailRefractive and diffractive contribution of linear chromatic aberration (LCA) on depth-of-focus with trifocal intraocular lenses (IOLs)
Loicq, Jerôme ULg; Gatinel, Damien

Poster (2016, September)

Purpose: To investigate the refractive and diffractive contribution of LCA on depth of focus extension of trifocal IOLs in polychromatic light conditions Setting: University of Liège, Belgium; Fondation ... [more ▼]

Purpose: To investigate the refractive and diffractive contribution of LCA on depth of focus extension of trifocal IOLs in polychromatic light conditions Setting: University of Liège, Belgium; Fondation Ophtalmologique A. de Rothschild, Paris Methods: The LCAs associated with the three focal points of hydrophobic and hydrophilic diffractive FineVision trifocal IOLs (PhysIOL SA, Liège, Belgium), were simulated in an Arizona eye model and experimentally measured on an optical bench at 480, 546 and 650 nm. The effect of Abbe number and aperture on different IOL materials was also evaluated. Based on wavelength–dependent MTF through-focus curves and PSF properties, polychromatic behavior of the trifocal IOLs was assessed under mesopic and photopic conditions. Results: LCA amplitude and sign were different for each of the trifocal IOL focal points. The diffractive LCA for near and intermediate was independent of IOL material (GFree versus hydrophilic acrylic, 26%), while far vision LCA appeared to be controlled by the material Abbe number. Under polychromatic conditions, the LCA contributed to depth of focus extension with different types of lens material, providing maximal visual acuity under white light conditions at all distances. Conclusions: Diffractive trifocal IOLs show chromatic aberrations with an increase in depth of focus under polychromatic light. This effect likely contributes to the extended range of vision. [less ▲]

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See detailIdentification of virulotypes and serotypes of enteropathogenic (EPEC) and Shigatoxigenic (STEC) Escherichia coli from healthy cattle at slaughterhouses in Wallonia.
Takaki, Shino; Duprez, Jean-Noël ULg; Fakih, Ibrahim et al

Poster (2016, September)

Escherichia coli producing the attachment-effacement (AE) lesion (EPEC) and/or Shiga toxins (STEC) cause enteritis and (bloody) diarrhoea in young calves and in humans, and are also present in the ... [more ▼]

Escherichia coli producing the attachment-effacement (AE) lesion (EPEC) and/or Shiga toxins (STEC) cause enteritis and (bloody) diarrhoea in young calves and in humans, and are also present in the intestines of healthy cattle. Besides the O157:H7 serotype, which is the main serotype causing STEC outbreaks in the world EPEC and STEC can belong to dozens of O serogroups. Of them, 9 have been frequently identified worldwide: O5, O26, O103, O104, O111, O118, O121, O145 and O165. The aim of this study is to identify the virulotypes and the O serotypes of EPEC and STEC isolated from healthy cattle at slaughterhouses in Wallonia. A total of 245 faeces (216 <1year-old bulls, 25 cows and 4 heifers) were sampled between April and June 2014 in 2 slaughterhouses in Wallonia and grown overnight at 37°C in Lauryl sulfate Enterobacteriaceae selective broth. The enrichment broths were assayed with an stx1, stx2 (Shiga toxin) and eae (AE lesion) triplex PCR and positive broths were inoculated onto 4 agar media: McConkey’s, Chromagar ES, Chromagar ES with tellurite and Chromagar STEC. Up to ten colonies per plate were picked up, sub-cultured and tested by the colony hybridization assay with gene probes targeting the stx1, stx2 and eae genes. The triplex PCR was again performed on all probe-positive isolates. The PCR-positive E. coli were subsequently assayed with two pentaplex PCR targeting the specific genes coding for the ten O serogroups listed above. Of the 2563 sub-cultured isolates, 744 isolates (29%) from 62 animals (25%) tested positive with the colony hybridization assay. Of them, 687 isolates (92%) from 59 animals were positive with the triplex PCR and the results of both tests were in agreement for 617 isolates (83%). One to 29 isolates per animal were probe- and PCR-positive. The positive isolates grew on Chromagar STEC (379; 55%), on Chromagar ES with tellurite (189; 28%), on Chromagar ES (62; 9%) or on McConkey’s agar (57; 8%). The most frequent virulotypes were eae+ (EPEC: 372 isolates; 54%), eae+stx1+ (AE_STEC: 119 isolates; 17%) and stx2+ (STEC: 118 isolates; 17%). In some animals different virulotypes were identified. The serogrouping with the two pentaplex PCR is in progress. AE-STEC, EPEC and STEC are excreted by 25% of the healthy cattle at slaughterhouses in Wallonia and different virulotypes can be excreted by the same animal. Conversely the methodology followed gives no precise idea of the actual level of excretion since the hybridization and PCR were performed after enrichment in selective broth. Therefore multiple isolates belonging to the same virulotype might represent the same clone. Identification of the serogroups and comparison by Pulsed Field Gel Electrophoresis should help to clarify that point. Quantitative (q)PCR is today the best method to quantify bacterial excretion, but is more expensive. The results of the hybridization and PCR correspond to between 80 and 90%. Though the colony hybridization is still useful for large-scale surveillance it needs radioactive probes for highest sensitivity and is more time-consuming than PCR. Therefore the PCR should be the first routine choice if it can be automatized at large scale. Further steps are the confirmation of the PCR results of the 70 isolates with different hybridization and PCR results and the identification of the serogroups with the two pentaplex PCR and later with PCR for the other serogroups, to compare them with isolates from young diarrhoeic calves and from humans. [less ▲]

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See detailThe BCCM/ULC collection to conserve and study the biodiversity of Polar cyanobacteria
Wilmotte, Annick ULg; Renard, Marine ULg; Lara, Yannick ULg et al

Poster (2016, September)

The BCCM/ULC public collection of Cyanobacteria has been funded since 2011 by the Belgian Science Policy Office. BCCM/ULC is currently holding 226 cyanobacterial strains, with 119 being of Antarctic ... [more ▼]

The BCCM/ULC public collection of Cyanobacteria has been funded since 2011 by the Belgian Science Policy Office. BCCM/ULC is currently holding 226 cyanobacterial strains, with 119 being of Antarctic origin (including 3 from the sub-Antarctic). The cyanobacteria constitute the bacterial phylum with the largest morphological diversity and their taxonomy is still a work in progress. In Polar Regions, Cyanobacteria represent key primary producers and are important drivers of the food webs in a wide range of aquatic to terrestrial habitats. For example, they build extensive 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 stresses. In this poster, we present the results of the 16S rRNA phylogenetic analysis for 76 Antarctic strains. This allows us to illustrate the diversity present in the collection, to detect lineages for which no genome has yet been sequenced, and to pinpoint taxonomic problems that should be addressed in a more comprehensive study. [less ▲]

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See detailTargeted mutagenesis of orphan GPCRs of the SREB family
Laschet, Céline ULg; Dupuis, Nadine ULg; Soni, Arvind ULg et al

Poster (2016, September)

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See detailIsolation of bacteriophages against Klebsiella pneumoniae and in vivo activity
Thiry, Damien ULg; Passet, Virginie; Dufour, Nicolas et al

Poster (2016, September)

Klebsiella pneumoniae is a bacterial pathogen able to induce severe healthcare-associated or community-acquired infections in humans and animals. The constant emergence of antibiotic resistant strains ... [more ▼]

Klebsiella pneumoniae is a bacterial pathogen able to induce severe healthcare-associated or community-acquired infections in humans and animals. The constant emergence of antibiotic resistant strains reinforces the need to find alternatives to antibiotic treatments. The use of bacteriophages is a promising approach. The aim of this study was to isolate bacteriophages directed against K. pneumoniae strains and to test their efficacy in a murine model. Bacteriophages against five different K. pneumoniae (2 of capsular type K1 and K2 and 1 undetermined) were isolated and purified from waste water collected in Paris area. The morphology of plaques (zones of bacterial killing) was recorded and several of them were purified three times by successive replating. Phage titers were determined by serial dilutions on their respective hosts as well as on 18 other Klebsiella strains to identify their host range. Kinetics of bacterial lysis were monitored during 15h at 3 multiplicities of infection, in triplicates. For in vivo experiment, a total of 10 mice were inoculated with 200 µl of K. pneumoniae (4.6E+07 CFU) by oral gavage and the level of K. pneumoniae in fecal samples was monitored for 10 days. Five mice did not receive any treatment and 5 other mice received a cocktail of three bacteriophages (8E+07 PFU) at day 4 post-inoculation. A total of 54 bacteriophages were isolated and purified with titers ranging from 2E+5 to 3.6E+10 PFU/ml. The host range study showed that bacteriophages against K. pneumoniae have a specificity related to the capsular type of their bacterial host. Lysis kinetics of bacteria suggested that different phages were isolated. Despite difficulties with the murine intestinal model, evidence was obtained that bacteriophages are able to reduce intestinal carriage. Our results show that bacteriophages isolated against K. pneumoniae are specific for a given capsular type, although further studies are necessary to provide more details on this capsular specificity and its molecular determinants. To fully address the in vivo potential of phages, a reliable mouse model of intestinal carriage of K. pneumoniae strains needs to be established. [less ▲]

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