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See detailDo aphids and their predators use the same OBP to transport a same odour?
Vandermoten, Sophie ULg; Fan, Jia; Liu, Yong et al

Poster (2010, August)

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See detailFemale fertility expression in Walloon dairy cattle
Vanderick, Sylvie ULg; Bastin, Catherine ULg; Gengler, Nicolas ULg

Poster (2010, August)

A useful method to express female fertility of the Walloon dairy cattle using direct and indirect female fertility information was considered. Data were based on results of the genetic evaluation of ... [more ▼]

A useful method to express female fertility of the Walloon dairy cattle using direct and indirect female fertility information was considered. Data were based on results of the genetic evaluation of pregnancy rate for 606,328 Holstein cows and on INTERBULL proofs of female fertility for 88,496 bulls. A direct female fertility index (DFF), using INTERBULL proofs, was developed from results of a principal component analysis carried out on 6 published foreign female fertility indexes. An indirect female fertility index (IFF) was also developed from ten other traits evaluated in Walloon Region. Theory of selection index was used to combine DFF and IFF in a global index called combined female fertility index (CFF). This index allowed young bulls to have better reliabilities with an average increase of 12% leading to extra 4,019 of publishable bulls for female fertility. [less ▲]

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See detailHammett Acidity Scale in Ionic Liquids : An Indication of Their Weak Dissociating Character
Robert, Thierry ULg; Magna, Lionel; Olivier-Bourbigou, Hélène et al

Poster (2010, August)

Ionic liquids are salts with the particularity to exhibit melting points near room temperature (below 100°C, by convention) with no vapour tension. For this last reason, ionic liquids are sometimes called ... [more ▼]

Ionic liquids are salts with the particularity to exhibit melting points near room temperature (below 100°C, by convention) with no vapour tension. For this last reason, ionic liquids are sometimes called “green solvents”. In addition, their exclusive materials and solvent properties has led to an amazing increase of interest from both academic and industrial community, confirmed by the explosion of the number of published papers in the last decade. The many combinations of organic and inorganic cations and anions allow an infinity of new ionic solvents then permitting the selection of the desired properties for a given application. Nevertheless, it is impossible to investigate all these combinations and the unusual complexity of these new solvents gives rise to many controversies. Consequently, the development of the general rules for understanding the chemistry in ionic liquids is crucial. A fundamental property of solvent is its solvating power, for instance towards the proton. Therefore, we are interested to investigate the acid-base properties in ionic liquids in order to ultimately find a correlation with the acidic catalysis activity. We then have proposed a colorimetric method to determine the acidity levels accessible in these new media: the Hammett acidity function H0. This spectroscopic method is based on the protonation equilibrium for a family of coloured indicator with pKa’s assumed as solvent independent (following the Hammett proposition). This presentation will summarize our Hammett acidity measurements in several ionic liquids. - At first, we will show that it is possible to evaluate the Hammett acidity function with two different coloured indicators, in the same ionic liquid. Since the Hammett acidity of a given mixture was found to depend on the choosen coloured indicator, this suggests the formation of ions associations in ionic liquids. As a result, the ionic liquids are clearly not as dissociating as initially thought and the Hammett acidity function is in fact an apparent function, underestimating the real acidity level. - The apparent acidity functions have then been compared for several ionic liquids to which an acid has been added ([BMIm][NTf2], [BMIm][BF4], [BMIm][OTf], [BHIm][NTf2], [BMIm][PF6], [HNEt3][NTf2]). The conclusions are as follows: 1) the accessible acidity level is not influenced by the nature of the cation; 2) on the contrary, the nature of anion is very critical and the solvating power towards the proton follows the order: OTf- > NTf2- > BF4- > PF6-. The more the proton is solvated, the less it is acidic. - Finally, the difference of acidity of two acids, HOTf and HNTf2 (both strong acids in water), has been investigated in [BMIm][BF4], [BMIm][NTf2] and [BMIm][OTf]. In [BMIm][OTf], these two acids show the same acidity (they behave as strong acids) due to the solvent levelling effect; on the other hand, in [BMIm][NTf2] and [BMIm][BF4] allowing higher acidity levels, HNTf2 is stronger than HOTf . The observed difference is also another indication of the lower proton solvation in [BMIm][BF4] or [BMIm][NTf2] versus that in [BMIm][OTf]. [less ▲]

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See detailFirst-Principles Study of Oxidation Mechanism for SiC-based Materials
Xu, Bin ULg; Kroll, Peter

Poster (2010, August)

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See detailFungal gene expression in a forest soil
Kellner, Harald ULg; Portetelle, Daniel ULg; Vandenbol, Micheline ULg

Poster (2010, August)

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See detailInvolvement of odorant cues in the process of superparasitism avoidance
Vandermoten, Sophie ULg; Frere, Isabelle; Hance, Thierry et al

Poster (2010, August)

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See detailInvolvement of odorant cues in the process of superparasitism avoidance
Verheggen, François ULg; Vandermoten, Sophie ULg; Frere, Isabelle et al

Poster (2010, August)

The ability to avoid superparasitism provides a selective advantage to parasitoid females, allowing them to avoid depositing eggs in lower quality host. We observed in a Y-olfactometer that generalist ... [more ▼]

The ability to avoid superparasitism provides a selective advantage to parasitoid females, allowing them to avoid depositing eggs in lower quality host. We observed in a Y-olfactometer that generalist aphid parasitoids, Aphidius ervi and Aphidius rhopalosiphi (Hymenoptera, Braconidae), were more attracted toward non-parasitized than parasitized Sitobion avenae (Hemiptera, Aphididae) colonies. We collected the odors released from healthy aphids and aphids parasitized for 2 and 6 days using an electronic nose. Sitobion avenae alarm pheromone, (E)-ß-farnesene (EßF), was the only chemical identified, and was found in lower quantities in parasitized aphids. Both parasitoid species provided pronounced electrical depolarizations to EßF in electroantennography (EAG), and both were attracted to the latter compound in the Y-olfactometer. Parasitoid attraction was known to be guided by a variety of odorant cues released by plants and hosts, and our results support the hypothesis that the aphid alarm pheromone acts as a kairomone for A. ervi and A. rhopalosiphi. [less ▲]

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See detailTransport and interaction blockade of cold bosonic atoms in a triple-well potential
Schlagheck, Peter ULg; Malet, Francesc; Cremon, Jonas C. et al

Poster (2010, August)

We investigate the transport properties of cold bosonic atoms in a triple-well potential that consists of two large outer wells, which act as microscopic source and drain reservoirs, and a small inner ... [more ▼]

We investigate the transport properties of cold bosonic atoms in a triple-well potential that consists of two large outer wells, which act as microscopic source and drain reservoirs, and a small inner well, which represents a quantum-dot-like scattering region. Such configurations can be realized by optical triple-well lattices generalizing the setup realized in the interaction blockade experiment by Cheinet et al. [Phys. Rev. Lett. 101, 090404 (2008)]. Bias and gate "voltages" are introduced in order, respectively, to tilt the triple-well configuration and to shift the energetic level of the inner well with respect to the outer ones. By means of exact diagonalization considering a total number of 6 atoms in the triple-well potential, we find diamond-like structures for the occurrence of single-atom transport in the parameter space spanned by the bias and gate voltages, in close analogy with the Coulomb blockade in electronic quantum dots. We demonstrate how one can infer the interaction energy in the central well from the distance between the diamonds, and discuss the possibility of realizing single-atom pumping across the quantum dot. [less ▲]

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See detailImpacts of growth development and age at first calving on first lactation yield in Holstein dairy cows
Picron, Pascale ULg; Froidmont, Eric; Turlot, Amélie et al

Poster (2010, August)

In a context of economic constraints, reducing the herd replacement costs represents a way to improve the economic efficiency of the dairy sector. Studies reported that heifers calving between 23 and 24.5 ... [more ▼]

In a context of economic constraints, reducing the herd replacement costs represents a way to improve the economic efficiency of the dairy sector. Studies reported that heifers calving between 23 and 24.5 mo of age achieved the highest economic return. However, the heifer has to be well developed to guarantee milk performance, calving ease and low stillbirth rate. Monitoring growth, by Heart Girth (HG) measurements, constitute a convenient way to evaluate the feasibility to inseminate heifers early. The aim of this study was to analyse the relationship between HG, age at first calving and milk production at first lactation. HG measurements of 704 Walloon (Belgium) Prim Holstein heifers have been recorded, every 3 months, during 2 years (2006 – 2008). The impact of development, at key-ages (from 3 to 24 mo, every 3 mo), on age at first calving and first lactation yield, was determined using analysis of variance. Mean total milk production in February 2010 (n = 319) rose to 7686 ± 1388 l/365 days of lactation, for a mean age at first calving (n = 421) of 27.4 ± 3.5 mo. These preliminary results suggest a positive correlation between growth performances and first calving age. Heifers with a better conformation (HG > 2.5 % of the French reference) calved significantly earlier than smaller animals. For instance, a lack of conformation at 15 mo implied a delay at first calving of 4.1 mo of age. HG measurement should therefore constitute a preferential tool of management of heifers herd. First lactation yield was significantly higher (950 l/365 d) for heifers calving older (> 30 mo) comparatively to early calving animals (24 mo). These results do not correspond to those related to larger samples in Wallonia. No significant relation could state, at this time, a direct relation between growth development and first lactation yield. Lactation data are still collected to complete this study. [less ▲]

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See detailProcessing of linguisitic and musical dimensions contained in songs : effects of an expertise
Larrouy, Pauline ULg; Leybaert, Jacqueline; Kolinsky, Régine

Poster (2010, August)

Songs are universal in our lives and also offer an ecological material that links linguistic and musical information. It therefore provides a tool for observing the relationship between music and language ... [more ▼]

Songs are universal in our lives and also offer an ecological material that links linguistic and musical information. It therefore provides a tool for observing the relationship between music and language. To examine the specificity of language and music information processing in songs, we studied the influence of expertise (i.e. musicians or speech therapists) on the use of transitional probabilities (TPs) in learning an artificial language (AL) either spoken or sung. This type of implicit statistical learning is especially important in language development (Saffran, Aslin, & Newport, 1996). We used the paradigm designed by Schön, Boyer, Moreno, Besson, Peretz and Kolinsky (2008). These authors have demonstrated the benefit of structural and motivational proprieties of music contained in the song in the learning process of AL in individuals with no expertise. Compared to a spoken AL, learning was enhanced for a singing AL, especially when the TPs of musical and linguistic materials were congruent. Our results did not replicate those of this study in participants having no music expertise. However, an interaction occurred between the type of AL and expertise of the participants. Indeed, only music experts seemed to benefit from the congruence between the TPs of musical and linguistic materials in extracting TP-based linguistic units. On the opposite, experts in language seemed to be favoured by the incongruence between the TPs of linguistic and musical information. These results are discussed in relation to the notions of the specificity of processing of lyrics and tunes in songs. [less ▲]

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See detailComparison of MRI images obtained at 7T in a dog to macroscopic and histopathological examination
Van Thielen, B.; Visser, F.; Denolin, V. et al

Poster (2010, July 20)

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See detailEffects of dietary methylmercury on the Zebrafish (Danio rerio) liver proteome
Brésart, David ULg; Fourdrilis, Séverine; Mathy, Grégory ULg et al

Poster (2010, July 19)

Methylmercury (MeHg) is an aquatic pollutant. It is produced from HgS by the action of sulphate-reducing bacteria and is released in fresh waters. MeHg is bioaccumulated through the trophic chain and is ... [more ▼]

Methylmercury (MeHg) is an aquatic pollutant. It is produced from HgS by the action of sulphate-reducing bacteria and is released in fresh waters. MeHg is bioaccumulated through the trophic chain and is known to cause different health troubles (trembling, memory loss, anemia and kidney deficiency). Toxic exogenous substances, such as MeHg, are transformed by liver’s metabolic pathway, making this the starting point of vertebrate detoxication. Almost 50% of MeHg assimilated in hepatocytes is accumulated in mitochondria (Ware et al.,1975) and It has been suggested that it may uncouples OXPHOS (Mori et al., 2007). The aim of this study was to identify the proteomics modifications of the liver mitochondrial proteome in response to a chronic MeHg intoxication by using the 2D DIGE methodology (Figure 1). Fishes were fed with two different contaminated diets (6.5 and 13.5 µg of MeHgCl / g of dry food.). We have also performed functional assays in order to confirm the MeHg uncoupling effect on Salmo truita liver mitochondria. [less ▲]

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See detailProteomic evolution of s.cerevisiae during chronological aging
Blomme, Arnaud ULg; Mac Cord, Allan ULg; Sluse, Francis ULg et al

Poster (2010, July 19)

Opposite to the replicative aging, which refers to the exponential decline in the capacity of a single cell to divide, chronological aging of the yeast Saccharomyces cerevisiae refers to the time period a ... [more ▼]

Opposite to the replicative aging, which refers to the exponential decline in the capacity of a single cell to divide, chronological aging of the yeast Saccharomyces cerevisiae refers to the time period a yeast cell can survive in a non-dividing state. In 2006, Allen and co-workers reported that yeast cells evolve into two cell types during stationary phase: a high density population defined as quiescent cells (Q) and a low density population defined as non-quiescent (NQ) cells. These two populations mainly differ by their viability, measured as the ability to form colonies when platted on Petri dishes, and can be separated by differential centrifugation on density gradient. In this work, we used the quantitative proteomics technique of 2DDIGE (two Dimensional Differential In-Gel Electrophoresis) to compare the evolution of the yeast cellular soluble proteome during chronological aging. We also checked the impact of the carbon source on stationary-phase cell differentiation. As the ratio of Q/NQ cells is decreasing with time, we have selected three distinct periods: 0 day (32h after outset of yeast culture on glucose, 100% of Q cells), 7 days (50% of Q cells) and 14 days (100% of NQ cells) to realize 3 proteomics comparisons (fig 1). [less ▲]

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See detailRole of Keratinocytes GPR109A and COX-2 in Nicotinic Acid and Mono-methyl Fumarate Induced Flushing
Hanson, Julien ULg; Gille, Andreas; Zwykiel, Sabrina et al

Poster (2010, July 17)

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See detailEFFECTIVENESS OF VOICE THERAPY RELYING ON THE USE OF EUTONY IN THE TRAITEMENT OF DYSPHONIC PATIENTS.
Martinot, Gisèle; Caner, Jessie; Morsomme, Dominique ULg

Poster (2010, July 15)

Twenty six patients with dysphonia (different etiologies) were submitted to a voice therapy program involving the use of Eutony. In order to assess its efficacy, pre and post-treatment audio recordings ... [more ▼]

Twenty six patients with dysphonia (different etiologies) were submitted to a voice therapy program involving the use of Eutony. In order to assess its efficacy, pre and post-treatment audio recordings were analysed and submitted to perceptual rating using GRBAS-I scale and acoustical analysis of fundamental frequency, jitter and shimmer. Aerodynamic data (Maximum Phonation Time & Estimated Subglottic Pressure) were also included in the voice quality assessment protocol. In addition , a questionnaire was sent to all patients to collect self-evaluation of voice quality and therapy outcomes. The study revealed a significant improvement lasting in time for two acoustic parameters : Jitter and Shimmer and five perceptual parameters : Grade, Roughness, Breath, Asthenia and Strain. Aerodynamic data showed slight improvements but no significant changes. Self evaluation questionnaires also tend to strengthen positive effects of therapy. Thus, this study supports the use of Eutony in vocal therapy for dysphonia. Its effects were shown to be measurable with both acoustical analysis and perceptual rating of voice quality. [less ▲]

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See detailContribution of "click chemistry" to the macromolecular engineering of aliphatic polyesters
Riva, Raphaël ULg; Schmeits, Stephanie ULg; Croisier, Florence ULg et al

Poster (2010, July 13)

In this work, click chemistry was sucessfully applied to the chemical modification of aliphatic polyesters with the purpose to tailor their physical properties. The developped strategy was then applied to ... [more ▼]

In this work, click chemistry was sucessfully applied to the chemical modification of aliphatic polyesters with the purpose to tailor their physical properties. The developped strategy was then applied to the synthesis of materials, such as smart partially degradable hydrogels or antibacterial polyesters. Last, the synthesis of amphiphilic star-shaped copolyester was investigated. [less ▲]

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See detailFacing the problem of the bis(acetylacetonato)cobalt(II)-mediated radical polymerization of acrylates
Hurtgen, Marie ULg; Debuigne, Antoine ULg; Jérôme, Christine ULg et al

Poster (2010, July 13)

Cobalt-Mediated Radical Polymerization (CMRP) is an efficient tool for polymerizing acrylates and vinyl esters. However, a challenge in CMRP remains in controlling the polymerization of both types of ... [more ▼]

Cobalt-Mediated Radical Polymerization (CMRP) is an efficient tool for polymerizing acrylates and vinyl esters. However, a challenge in CMRP remains in controlling the polymerization of both types of monomers with the same cobalt complex. Here, we show how Co(acac)2, efficient for unconjugated vinyl monomers, can also cope with acrylates. [less ▲]

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See detailStudy of oxylipins pathways by a transcriptomic analysis of two variety of
Ghars, Mohamed Ali ULg; Muhovski, Y.; Ghanem, M. et al

Poster (2010, July 11)

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See detailFunctionalization of carbon xerogels for the preparation of Pd/C catalysts by grafting of Pd complex
Diverchy, C.; Hermans, S.; Job, Nathalie ULg et al

Poster (2010, July 11)

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See detailImmobilization of homogenous catalysts in nanostructured carbon materials
Gheorghiu, C. C.; Pérez-Cadenas, M.; Roman-Martinez, M. C. et al

Poster (2010, July 11)

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See detailIs there a generalized procedural deficit in children with Specific Language Impairment?
Gabriel, Audrey ULg; Maillart, Christelle ULg; Guillaume, Mélody et al

Poster (2010, July 08)

Previous studies (Lum et al., 2009; Tomblin et al., 2007; Ullman & Pierpont, 2005) have suggested that difficulties in the procedural learning system could contribute, in part, to the language ... [more ▼]

Previous studies (Lum et al., 2009; Tomblin et al., 2007; Ullman & Pierpont, 2005) have suggested that difficulties in the procedural learning system could contribute, in part, to the language difficulties observed in children with SLI. However, we have recently shown, with an adapted serial reaction time (SRT) task, that children with SLI are able to learn implicitly non-linguistic regularities (Gabriel et al., submitted). In this research, we wanted to determine whether children with SLI are able to learn an 8-elements probabilistic sequence into which irregularities are inserted. Assessing probabilistic sequence learning in children with SLI should help us to better circumscribe the language difficulties of these children [less ▲]

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See detailTiO2 thin films (1 µm) with ordered porosity used as high performance photoelectrode in DSSC
Dewalque, Jennifer ULg; Cloots, Rudi ULg; Dubreuil, Olivier et al

Poster (2010, July 06)

Mesoporous anatase thin films are very promising materials to act as electrode in dye-sensitized solar cells. Randomly oriented nanocrystalline TiO2 particles are usually used to prepare photoelectrodes ... [more ▼]

Mesoporous anatase thin films are very promising materials to act as electrode in dye-sensitized solar cells. Randomly oriented nanocrystalline TiO2 particles are usually used to prepare photoelectrodes with a thickness of 10-15 µm. Templated-assisted dip-coating techniques are used to obtain thin films with ordered porosity. The use of different templates influences the film porosity in terms of long-range order, percentage of porosity, pore size and pores connectivity. The photovoltaic performances of the samples have been evaluated. Such mesostructured films are compared in terms of photovoltaic performance with TiO2 nanoparticles films, generally used in DSSC. [less ▲]

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See detailDiversité des pucerons en parcelles de pomme de terre et impact sur la dissémination des viroses
Yattara, Almouner Ag Alhamis ULg; Véronique Genin, Lionel Hartert; Francis, Frédéric ULg

Poster (2010, July 05)

Protect crops against aphids is even less easy than the high proliferation potential and possible infestation by winged individuals from distant homes, require on the part of farmers regularly monitored ... [more ▼]

Protect crops against aphids is even less easy than the high proliferation potential and possible infestation by winged individuals from distant homes, require on the part of farmers regularly monitored. In addition, in the case of aphid vectors of virus diseases, it is necessary to detect the first attacks to limit the spread of the disease within the plot. In 2009, the abundance and diversity of aphids was studied using the yellow bins installed in a network of nine plots of potatoes throughout Wallonia. The evaluation of the diversity and abundance of aphid species were evaluated weekly by collecting the insects captured. At the same time catch and observations on the plots, a sample of thirty leaves of potato is taken from each of the nine plots and analyzed in the laboratory to detect any viral infections, mainly PVY and PLRV. During the growing season, six species of aphid were particularly abundant: Metopolophium dirhodum, Sitobion avenae, Aphis fabae, Macrosiphum euphorbiae, Rhopalosiphum padi and Acyrthosiphon pisum. The ELISA performed on leaf samples taken from different plots of potato revealed the presence of PVY and PLRV in six of nine plots sampled. We observed a greater diversity of aphid species in almost all plots investigated. [less ▲]

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See detailRetrospective evaluation of 9 horses with surgical treatment of keratoma
Salciccia, Alexandra ULg; Bouhmala, Nabil; Serteyn, Didier ULg et al

Poster (2010, July 02)

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See detailClotridial hydrogenases and the biohydrogen production
Calusinska, Magdalena ULg; Hamilton, Christopher ULg; Masset, Julien ULg et al

Poster (2010, July 01)

Among the large variety of microorganisms capable of fermentative hydrogen production, strict anaerobes such as Clostridium spp. are one of the most widely studied. They produce hydrogen by butyric and ... [more ▼]

Among the large variety of microorganisms capable of fermentative hydrogen production, strict anaerobes such as Clostridium spp. are one of the most widely studied. They produce hydrogen by butyric and mixed-acid fermentations at optimal pH values ranging from 4.5 to 5.5. While fermentative conditions such as substrate type, pH, hydraulic and solid retention time, H2 partial pressure and the concentration of acids produced have been extensively studied and optimized, relatively little is known about the different forms of hydrogenases present in clostridia. Building on previous reports [1, 2] and by analyzing sequenced genomes, we found that [FeFe] hydrogenases are not a homogenous group of enzymes, but exist in multiple forms with different modular structures and are especially abundant in Clostridum spp. [3]. However, among the numerous studies performed on fermentative hydrogen production by Clostridium sp., only a few are specifically concerned with hydrogenases. Even there the authors focus on one type of [FeFe] hydrogenase, (CpI-like) without considering the existence of multiple forms of this enzyme within one species. Therefore, we focused our research on the better characterization of different forms of hydrogenases present in the genus Clostridium. Using newly designed degenerate primers, specific for clostridial hydrogenases, we amplified different hydrogenases from our species of interest. Further, by designing specific qPCR assays we have quantitatively targeted different hydrogenases. By analyzing differential gene expression, according to applied growth conditions, we believe to optimize the hydrogen production process in order to achieve better production rates. To conclude, we think that a a precise knowledge of hydrogen metabolism and hydrogenases is essential to optimization of the biohydrogen production process and should therefore be a goal for future research. [less ▲]

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See detailMapping of kisspeptin projections in the midbrain of the pro-oestrus rat
Desroziers, Elodie ULg; Mikkelsen, Jens; Simmoneaux, Valérie et al

Poster (2010, July)

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See detailDetection of differential item functioning with the difR package
Magis, David ULg; Béland, Sébastien; Tuerlinckx, Francis et al

Poster (2010, July)

The purpose of this talk is to briefly present the package difR of the software R. This package permits to identify differential item functioning (DIF) with several parametric or nonparametric methods ... [more ▼]

The purpose of this talk is to briefly present the package difR of the software R. This package permits to identify differential item functioning (DIF) with several parametric or nonparametric methods. Nonparametric methods include: Mantel-Haenszel, standardization, logistic regression and Breslow-Day. Available parametric methods are the Lord’s chi-square test, the Raju’s area method, and the likelihood-ratio test. Some methods for DIF identification in multiple groups (generalized Mantel-Haenszel, generalized Lord’s test) are also available. The presentation focuses on the package and its potential, rather than on the included methods. Its performance will be illustrated with an example data set. [less ▲]

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See detailActivated-carbon-xerogel/TiO2-P25 composite photocatalysts with high activity for the degradation of p-nitrophenol
Páez Martínez, Carlos ULg; Contreras, María; Olivera-Fuentes, Claudio et al

Poster (2010, July)

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See detailA role for PSA-NCAM-dependent neuron-glia interactions in the control of GnRH neuron activity
Franceschini, Isabelle; Desroziers, Elodie ULg; Lomet, Didier et al

Poster (2010, July)

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See detailAn in-situ NMR analysis of the formation of P- and SiO2-doped TiO2 xerogels
Bodson, Céline ULg; Lambert, Stéphanie ULg; Cattoën, Xavier et al

Poster (2010, July)

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See detailKraft recovery boiler analysis : a data mining approach
Sainlez, Matthieu ULg

Poster (2010, July)

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See detailMultifractality in the kicked rotator
Martin, John ULg; Garcia-Mata, Ignacio; Giraud, Olivier et al

Poster (2010, July)

Detailed reference viewed: 37 (9 ULg)
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See detailThe essential role of the plastidial glyceraldehyde- 3-phosphate dehydrogenase in viable pollen development in Arabidopsis
Muñoz-Bertomeu, Jesús; Cascales - Miñana, Borja ULg; Anoman, Armand D. et al

Poster (2010, July)

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See detailMultiqubit symmetric states with a high geometric entanglement
Martin, John ULg; Giraud, O.; Braun, P. A. et al

Poster (2010, July)

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See detailRegulation of GnRH-1 neurons by glial cells: an in vitro study
Desroziers, Elodie ULg; Kolasa, Elise; Franceschini, Isabelle et al

Poster (2010, July)

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See detailA phylogenomic falsification of the chromalveolate hypothesis
Baurain, Denis ULg; Brinkmann, Henner; Petersen, Jorn et al

Poster (2010, July)

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See detailMassive binaries as seen with GAIA
Palate, Matthieu ULg; Rauw, Grégor ULg; Gosset, Eric ULg et al

Poster (2010, July)

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See detailA MODEL FOR WHEAT YIELD PREDICTION BASED ON REAL-TIME MONITORING OF ENVIRONMENTAL FACTORS
Dumont, Benjamin ULg; Lebeau, Frédéric ULg; Vancutsem, Françoise ULg et al

Poster (2010, July)

This paper presents the results of a one year preliminary study in which a real time monitoring system was used to feed the STICS soil crop model. As indicated by the statistical criteria (RMSE and model ... [more ▼]

This paper presents the results of a one year preliminary study in which a real time monitoring system was used to feed the STICS soil crop model. As indicated by the statistical criteria (RMSE and model efficiency), the optimization of some wheat crop parameters allows the model to predict the yields with good accuracy for different soil type and different nitrogen application rates. [less ▲]

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See detailMorphologie de la mineuse des fruits du safoutier
Poligui, René Noël ULg; Mouaragadja, Isaac; Francis, Frédéric ULg et al

Poster (2010, July)

L’étude de l’entomofaune des associations culturales prenant en compte le safoutier a permis de mettre en évidence des fortes abondances et une diversité des familles entomologiques. Au niveau des ... [more ▼]

L’étude de l’entomofaune des associations culturales prenant en compte le safoutier a permis de mettre en évidence des fortes abondances et une diversité des familles entomologiques. Au niveau des ravageurs majeurs, nous avons caractérisé un lépidoptère (tortricidae) dont les larves minent les noyaux des fruits du safoutier (Dacryodes edulis) et peuvent induire une chute prématurée d’au moins 25% de fruits. Toutes petites, les larves sont blanches et tachetées de points noirs, puis dans leur dernier stade, elles sont roses avec la tête, les plaque anale et prothoracique brunes. La chrysalide se forme dans un cocon de soie blanc. Elle est brune au départ et noir en fin de nymphose, et se caractérise par un crémaster noir proéminent au milieu de deux paires de soie recourbées à leurs extrémités. La nymphose dure au moins 20 jours. L’adulte est un paillon gris terne. Outre le safoutier, ce lépidoptère a été trouvé dans les fruits de Pseudopdondias longifolia. Des investigations ultérieures révéleront certainement d’autres plantes hôtes et permettront d’envisager une lutte biologique efficiente contre cette mineuse des fruits. [less ▲]

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See detailEntomofaune du safoutier (Dacryodes edulis (G. Don) H.J. Lam ; Burseraceae) au Gabon : résultat dune première année d’investigation
Poligui, René Noël ULg; Mouaragadja, Isaac; Haubruge, Eric ULg et al

Poster (2010, July)

L’entomofaune du safoutier (Dacryodes edulis (G. Don) H.J. Lam ; Burseraceae) a été étudié au moyen des pièges jaunes et des observations visuelles, pendant seize semaines au Gabon, dans la province du ... [more ▼]

L’entomofaune du safoutier (Dacryodes edulis (G. Don) H.J. Lam ; Burseraceae) a été étudié au moyen des pièges jaunes et des observations visuelles, pendant seize semaines au Gabon, dans la province du Haut-Ogooué. Cinq postes de piégeages ont été installés à Franceville et cinq autres en périphérie de la ville. Les deux méthodes situent l’évolution des insectes en deux vagues dont la première et la plus importante s’étend sur huit semaines, correspond à la période de floraison de l’arbre et de pleine croissance des fruits. La seconde vague va de l’arrêt de croissance des fruits à leur maturation. Le piégeage révèle que les abondances des insectes ainsi que leur diversité biologique par poste sont plus importantes en milieu rural qu’en milieu urbain. Le contrôle visuel présente des abondances relativement similaires, mais avec une diversité sensiblement plus élevée en milieu rural. Les sites à prédominance de savanes permettent des captures d’insectes plus importantes que ceux des forets. L’abondance est globalement moins élevée au niveau des arbres males pour les deux techniques d’étude. Par contre, les observations visuelles enregistrent les pics les plus élevés sur les arbres femelles, mais le piégeage les situe sur les arbres males. La diversité biologique est significativement mieux exprimée par le piégeage, alors que le contrôle visuel spécifie mieux le niveau et l’évolution des ravageurs. Les Aphididae, les Cicadellidae et les psyllidae constituent les familles numériquement les plus importantes des insectes nuisibles. Les Apidae, les coccinellidae et les halticidae forment les familles majeures des insectes utiles. Les Tortricidae constituent la famille ayant la plus grande incidence économique sur le safoutier. [less ▲]

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See detailKisspeptin immunoreactivity during post-natal development in rat.
Desroziers, Elodie ULg; Mikkelsen, Jens; Caraty, Alain et al

Poster (2010, July)

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See detailComputerized video multitracking of several small translucent fishes (glass eels) at night with fluorescent elastomer tags
Delcourt, Johann ULg; Bolliet, Valérie; Ylieff, Marc ULg et al

Poster (2010, July)

European eels (Anguilla Anguilla), an endangered species with high economic value, exhibit very unusual features in their multistage catadromous life cycle at different life stages. The reproduction of ... [more ▼]

European eels (Anguilla Anguilla), an endangered species with high economic value, exhibit very unusual features in their multistage catadromous life cycle at different life stages. The reproduction of eel takes place in the Sargasso Sea. Leptocephalus larvae use ocean currents (mainly the Gulf Stream) to migrate to European coastal areas, and then metamorphose into glass eels probably as they reach the continental shelf. Glass eel then, enter estuaries to join the fresh waters network. Knowledge about glass eel biology and migration has mainly increased in the eighties, and it is now well established that the activity during the estuary migration depends mainly on tidal cycle, even if lunar and circadian rhythms and/or direct influence of light and tidal coefficient may interact. Different migratory tactics are suspected on the basis of recent laboratory experiments (Bolliet & Labonne, 2008; Bureau du Colombier et al., 2009), notably the existence of individuals swimming only with the current, others swimming with and against the current, and others presenting a weak degree of activity. The propensity to migrate and glass eels energy content would be linked and may result in different migratory behaviours possibly leading to estuarine settlement (Bureau du Colombier et al., 2007; 2009). Unfortunately, few are known about the glass eel swimming behaviours in estuaries, a crucial point to better understand their estuarine migration: such knowledge would help to characterize the migratory tactics and to better understand the link with energy status. The videotracking system [EthoVision Color-Pro 3.1 (Noldus Information Technology)] which allows to measure automatically the movements of individuals represents an interesting tool to progress in this questioning. Nowadays, video tracking to measure fish behaviours is relatively frequent, but is rather rare in the ecological studies. Moreover, tracking a transparent animal, under water current conditions is a real challenge, particularly at night. To detect the individuals, several eels are marked by a fluorescent VIE tag (Visible Implant Elastomer, Northwest Marine Technology Inc.). VIE do no affect growth, survival and behaviour of tagged glass eels. Initially developed to improve the identification of individual tags in mark-recapture studies of aquatic animals, VIE tags are used here for a new extreme application in ethometry: the study of behaviours of transparent animals in weaker luminosity and in the dark by automatic tracking technology. The individual identification is based on the fluorescent color (red, blue, yellow and green) emitted by the VIE tag injected in the muscle mass on the basis of dorsal fin. The detection of the four marks is excellent. It allows measuring the activity (notably path and speed) of each tagged individuals as a function of tidal and nycthemeral rhythms in the same chronotron (circular aquarium simulating the estuarine conditions) and spatial use at a wide time scale from second to week. Another advantage is the possibility of tracked animals to go out the analysed arena without error of identification when it appears again in the analysed zone. This multitracking method by fluorescent VIE tags could be applied to a large number of species (crustaceans, fish, holothurians, amphibians, …). References: Bolliet & Labonne, 2008 Journal of Experimental Marine Biology and Ecology 362, 125-130; Bureau du Colombier et al., 2007 Physiology & Behavior 92, 684-690 ; Bureau du Colombier et al., 2009 Journal of Fish Biology 74, 2002-2013. Acknowledgements: This work was financially supported by FNRS-FRS (National fund of Research, Belgium) (project n°2.4617.08, n°2.4569.06, n°2.4569.10F), by Hubert Curien Tournesol project and by an EGIDE Grant. We thank J-C. Aymes for its help in testing the video tracking software and system. We are also highly grateful to Jacques Rives for its help in settling and monitoring the experiments. [less ▲]

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See detailAssociation des approches morphologique et moléculaire pour l’identification des vers à soies endémiques de Madagascar (Lasiocampidae, Borocera cajani)
Rakotondramanana, Alihasina; Nguyen, Bach Kim ULg; Verheggen, François ULg et al

Poster (2010, July)

La soie est une matière utilisée par les Malgaches depuis bien avant la colonisation. Cette soie est fabriquée à partir de la collecte de cocons des papillons du genre Borocera spp., ver à soie sauvage ... [more ▼]

La soie est une matière utilisée par les Malgaches depuis bien avant la colonisation. Cette soie est fabriquée à partir de la collecte de cocons des papillons du genre Borocera spp., ver à soie sauvage. On connaît une dizaine d’espèces de vers à soie sauvages endémiques à Madagascar. Ces lépidoptères polyphages se nourrissent surtout des feuilles de Uapaca bojeri et d’autres plantes telles que Dodonea madagascariensis et Psidium guyava. Les critères morphologiques se révèlent insuffisant pour identifier cette diversité d’espèces de vers à soie, surtout au niveau des stades immatures. Afin de pallier à cette incapacité d’identifier les espèces, des méthodes de marqueurs moléculaires, en particulier la RAPD (Random Amplified Polymorphic DNA) et iSSR (inter Simple Sequence Repeat), ont été appliquées. En plus de l’identification des espèces, une étude de la diversité et de la distribution des vers à soie suite à la collecte dans plusieurs forêts éloignées de plusieurs de kilomètres les unes des autres (Arivonimamo, Ambatofinandrahana, Antananarivo). Cette étude a été menée dans le cadre de la conservation de ces espèces de vers à soie endémiques en milieu. Afin d’augmenter durablement les populations de vers à soie endémiques dans les forêts de Uapaca, il est important de déterminer les espèces en présence et les capacités de dispersion de ces dernières. Les techniques d’identification moléculaires développées permettront d’orienter les stratégies de gestion des populations de Borocera et des méthodes de gestion de l’écosystème, appropriables par les gestionnaires et les communautés locales des la forêt à Uapaca bojeri. [less ▲]

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See detailNanocoatings of inorganic surfaces by molecular biomimetic
Vreuls, Christelle ULg; Genin, Alexis ULg; Zocchi, Germaine ULg et al

Poster (2010, June 30)

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See detailA green and refillable antibacterial coating for stainless steel
Faure, Emilie ULg; Charlot, Aurélia; Sciannaméa, Valérie et al

Poster (2010, June 29)

Because of its resistance to corrosion and chemicals, relevant mechanical and esthetical properties, stainless steel (SS) is widely used in the daily life (food industry, household appliances, surgery … ... [more ▼]

Because of its resistance to corrosion and chemicals, relevant mechanical and esthetical properties, stainless steel (SS) is widely used in the daily life (food industry, household appliances, surgery …). However, SS is unable to prevent bacteria from adhering, proliferating and forming a resistant biofilm when ageing. Therefore, surface modification is needed for providing durable antibacterial properties. We report here on an all-in-one approach to prepare refillable antimicrobial films using the layer-by-layer deposition of polyelectrolytes. Specifically designed biocidal multilayered polyelectrolyte films that bear 3,4-dihydroxyphenylalanine (DOPA), known as a promoter of adhesion to inorganic surfaces, were deposited onto SS. DOPA was incorporated in the polycationic chains by radical copolymerisation of N-methacrylated DOPA with the quaternary ammonium salt of 2-(dimethylamino)ethyl methacrylate (DMAEMA+). In order to boost the antibacterial activity of the polycationic layer, AgNO3 was added to the aqueous solution of P(DOPA)-co-P(DMAEMA+), which resulted in the in-situ formation of silver based nanoparticles, sources of biocial Ag+. The layer-by-layer deposition of aqueous P(DOPA)-co-P(DMAEMA+)/AgCl/Ag0 suspension and aqueous solution of poly(styrene sulfonate) provides high antibacterial activity against Gram-negative E. Coli bacteria. Moreover, after silver depletion, films retain some antimicrobial activity, thanks to ammonium groups of the copolymer. We also show that the antibacterial activity of the films can then be easily re-boosted. [less ▲]

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See detail(Functionnal) analysis of hydrogen production in Chlamydomonas reinhardtii mitochondrial mutants
Lecler, Renaud ULg; Godaux, Damien ULg; Hamilton, Christopher ULg et al

Poster (2010, June 27)

Mitochondrial Chlamydomonas mutants for respiratory complexes present a decreased dark respiration and apparent yield of photosynthetic linear electron flow. They accumulate reducing power such as NAD(P)H ... [more ▼]

Mitochondrial Chlamydomonas mutants for respiratory complexes present a decreased dark respiration and apparent yield of photosynthetic linear electron flow. They accumulate reducing power such as NAD(P)H and show lower levels of ATP. Under restrictive conditions, like sulfur depletion and anoxia, Chlamydomonas is able to produce hydrogen towards the activation of a chloroplatic O2-sensitive Fe-hydrogenase which catalyses the reduction of electrons to H2. In this study we used an adapted Melis protocol to analyse hydrogen evolution of mitochondrial mutants. For this aim a simple-flask system was built with gaz collecting tubes. A parallel flask was used for GC analyses. [less ▲]

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See detailUnimpaired Implicit Learning abilities in Children with Specific Language Impairment.
Gabriel, Audrey ULg; Fauconnier, Leslie; Meulemans, Thierry ULg et al

Poster (2010, June 26)

Previous studies (Lum et al., 2009; Tomblin et al., 2007; Ullman & Pierpont, 2005) have suggested that difficulties in the procedural learning system could contribute, in part, to the language ... [more ▼]

Previous studies (Lum et al., 2009; Tomblin et al., 2007; Ullman & Pierpont, 2005) have suggested that difficulties in the procedural learning system could contribute, in part, to the language difficulties observed in children with SLI. However, we have recently shown, with a classical serial reaction time (SRT) task, that children with SLI are able to learn implicitly non-linguistic statistical regularities (Gabriel et al., 2010). The aim of the present study was to explore whether children with SLI could learn similar statistical regularities with non-linguistic auditory stimuli. For this purpose, we compared performance of children with SLI and controls in two adapted SRT tasks: a visual SRT task and a non-verbal auditory SRT task. [less ▲]

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See detailAnalogical processes in language development in children with specific language impairment
Leroy, Sandrine ULg; Um, Marelle; Parisse, Christophe et al

Poster (2010, June 26)

Constructivist approach (Goldberg, 1995; Tomasello, 2003) considers that analogical reasoning is a cognitive process which underlies the abstraction of the linguistic forms and the construction of more ... [more ▼]

Constructivist approach (Goldberg, 1995; Tomasello, 2003) considers that analogical reasoning is a cognitive process which underlies the abstraction of the linguistic forms and the construction of more abstract linguistic schemas. When children hear two utterances such as “John eats an apple” and “She sees a bird”, they can infer the abstract schema [Subject Verb Object] by realizing analogies between the two utterances. Morphosyntactic disorders encountered by children with specific language impairment (SLI) could be caused by problems with analogies, what would hinder their abstraction of construction schemas. Consequently, children with SLI would be less productive with their language and would use more fixed linguistic forms. Owing to these problems of generalization, the morphosyntactic development of children with SLI would be slow down [less ▲]

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See detailInfluence of Sport Activity on Trunk Muscle Performances
Grosdent, Stéphanie ULg; Demoulin, Christophe ULg; Coupas, Amandine et al

Poster (2010, June 24)

Introduction: Lumbar pain among athletes is a common problem and can be challenging for athletic trainers and therapists. Unfortunately, little is known about the capabilities of trunk muscle function in ... [more ▼]

Introduction: Lumbar pain among athletes is a common problem and can be challenging for athletic trainers and therapists. Unfortunately, little is known about the capabilities of trunk muscle function in elite athletes Therefore, an objective assessment of muscle performance is relevant in injury prevention and rehabilitation. The purpose of this study was to examine the specific trunk muscle strength and endurance in different sports i.e. swimming, rowing and tennis. Methods: We assessed maximum isometric trunk extensor, rotator, flexor and lateroflexor muscle strength as well as trunk extensor muscle endurance of 10 swimmers, 10 rowers, 10 tennismen and 10 sedentary students (control group). Strength was measured by means of specific trunk dynamometers. An adaptation of the Sorensen test was performed to assess trunk extensor endurance. Results: Muscle strength appeared generally higher among athletes than among control subjects. However, differences were statistically significant only with swimmers for trunk flexors (p<0.05) and trunk rotators (p<0.05), with rowers for trunk flexors (p<0.05) and with tennismen for dominant lateroflexors (p<0.05) and non-dominant trunk rotators (p<0.05). No significant bilateral difference appeared for trunk lateralflexors strength. For trunk rotators, tennismen were significantly stronger in the non-dominant side (p<0.05). Trunk extensor endurance was higher among rowers than among the other groups. Conclusion: This study underlined several differences in trunk muscle performance between athletes and control subjects as well as within athletes groups in relation to their sports. Further studies would clarify the full significance of these results with respect to performance and injury. [less ▲]

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See detailAtypical myopathy in Europe: 2006-2009
Van Galen, Gaby ULg; Atypical Myopathy Alert Group; Votion, Dominique ULg

Poster (2010, June 18)

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See detailDendrochronology to date mettalic reinforcements in roof frames
Maggi, Christophe ULg; Pagès, Gaspard ULg; Hoffsummer, Patrick ULg et al

Poster (2010, June 17)

Studies about metallic reinforcements in historical monuments multiply themselves. Thanks to building archaeology and dendrochronology, we are able to determine the archaeological contexts to which the ... [more ▼]

Studies about metallic reinforcements in historical monuments multiply themselves. Thanks to building archaeology and dendrochronology, we are able to determine the archaeological contexts to which the metallic elements belong and to date them. One of the objectives of the research is to list the different appearances of iron in roof frames and to identify the function of each. At the end, the principal aim is to create a typo-chronological inventory which will index all the iron reinforcements met in medieval roof frames of the Meuse basin (Belgium). [less ▲]

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See detailLa sensibilité à l'anxiété chez l'enfant : Les facteurs de risque et de protection au sein de son milieu familial
Stassart, Céline ULg; Etienne, Anne-Marie ULg

Poster (2010, June 11)

La sensibilité à l'anxiété (AS)est la peur des sensations corporelles liées à l'anxiété. Plusieurs études constatent qu'une grande proportion de la variance de l'AS des filles et la totalité de la ... [more ▼]

La sensibilité à l'anxiété (AS)est la peur des sensations corporelles liées à l'anxiété. Plusieurs études constatent qu'une grande proportion de la variance de l'AS des filles et la totalité de la variance de l'AS des garçons s'expliquent par des facteurs environnementaux. L'objectif est de dégager, chez l'enfant au sein du milieu familial, les facteurs de risque et de protection de la sensibilité à l'anxiété (AS). Dans un premier temps, le lien entre divers états émotionnels des parents et la présence d'une AS chez leur enfant sera étudiée. La part contributive des mécanismes d'apprentissage (transmission d'information, renforcement, modeling) de l'AS lorsque l'enfant ressent des symptômes corporels sera également analysée. Différents effets seront testés: le type d esymptômes sur lequel l'apprentissage porte (douleur/anxiété), la source (père/mère) et la diversité des apprentissages. Dans un second temps, afin d'affiner les liens entre les états émotionnels des parents, les expériences d'apprentissage au sein du milieu familial et la présence d'une sensibilité à l'anxiété chez l'enfant, l'influence de deux modérateurs sera testée: l‘intelligence émotionnelle de l'enfant et les apprentissages sociaux. Les hommes apprennent qu'il est moins acceptable pour eux que pour les femmes d'exprimer leurs craintes. Les mères parlent plus volontiers de leurs inquiétudes et donc, lorsqu'elles présentent des manifestations anxieuses, elles peuvent plus facilement expliquer à l'enfant que ses peurs sont irrationnelles contrairement aux pères qui préféreront ne pas en parler. Que se passerait-il si le père parlait de ses craintes sachant qu'un père qui oserait exprimer sa détresse sera perçu de façon plus marquante par son enfant qu'une mère qui ose le faire? [less ▲]

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See detailIs posterior cerebral hypometabolism always predicitve of dementia in Parkinson's disease?
Deville, Benjamin ULg; Lemaire, Christian ULg; Degueldre, Christian ULg et al

Poster (2010, June 08)

In Parkinson's disease, altered activity in posterior associative cortices has often been associated with dementia. It remains to be determined if this pattern is a reliable marker of a progression toward ... [more ▼]

In Parkinson's disease, altered activity in posterior associative cortices has often been associated with dementia. It remains to be determined if this pattern is a reliable marker of a progression toward dementia in patients without demonstratable dementia. In this retrospective analysis, we used positron emission tomography to study resting-state cerebral fluodeoxyglucose uptake in 8 healthy controls and 8 Parkinson's disease patients who did not have evidence of dementia at the time of assessment. For those patients, clinical follow up was available and we know that they did not meet dementia criteria on average 10,37 years after assessment. The results show that patients had reduced fluodeoxyglucose uptake mostly localised in the right hemisphere and including precuneus, superior temporal, middle temporal and inferior parietal cortices. It also includes right insula. These cerebral activity predominating in posterior cortices is present in non-demened patients but is not always predictive of dementia within the 10,34 years. [less ▲]

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See detailCo‐construction du langage: le rôle de la mère dans les séquences de rectifications
Collombel, Marie; Maillart, Christelle ULg; Caet, Stéphanie et al

Poster (2010, June 07)

Notre recherche a pour but de mieux repérer ce qui semble faciliter chez l'enfant tout venant son développement linguistique et communicationnel, afin de mettre en place des stratégies éducatives adaptées ... [more ▼]

Notre recherche a pour but de mieux repérer ce qui semble faciliter chez l'enfant tout venant son développement linguistique et communicationnel, afin de mettre en place des stratégies éducatives adaptées aux enfants présentant des troubles du langage. Dans une étude longitudinale des interactions mère-enfant chez trois enfants tout-venant entre 1 an 6 mois et 3 ans, notre équipe s'est penchée sur un phénomène interactionnel au croisement de l'appropriation du système linguistique et de son usage : les rectifications. Nos analyses soulignent le rôle clé de la mère ainsi que les similarités et les différences entre les dyades. La sensibilisation à ces dimensions de la communication auprès de parents d'enfants dysphasiques dans le cadre d'un projet de guidance parentale pourrait favoriser la mise en place de formes d'interaction facilitant le développement langagier et communicationnel des enfants. [less ▲]

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See detailImpact of an anxious social situation on emotional facial expressions (EFE) recognition in children
Dethier, Marie ULg; Taskin, Asliane; Blairy, Sylvie ULg

Poster (2010, June 04)

Socially anxious children have difficulties to interact adequately with others. The core characteristic of social anxiety, the fear of being negatively evaluated by others, may among others, be based on ... [more ▼]

Socially anxious children have difficulties to interact adequately with others. The core characteristic of social anxiety, the fear of being negatively evaluated by others, may among others, be based on problems with the decoding of other persons’ emotional facial expression (EFE). Up to now, the research on EFE recognition in socially anxious children has produced mixed results. Whereas some studies reported differences between anxious and healthy children in EFE recognition (e.g., Simonian, Beidel, Turner, Berkes, & Long, 2001), others didn’t find such differences (Melfsen & Florin, 2002). In this study, we addressed two new issues in the investigation of EFE recognition in socially anxious children. Firstly, we investigated self-esteem. Socially anxious children show low confidence in one’s cognitive and social abilities. Furthermore, high self-esteem is related to high capacities of EFE recognition (Garfield, Rogoff, & Steinberg, 1987), and more generally to high level of social functioning (Serretti et al., 1999 ; Shapira et al., 1999). Indeed, the perception of ourselves depends on the way we think others people perceive us. Secondly, past researches have investigated this issue in low anxious situations and thus, not in situations in which social anxious individuals feel threatened. The originality of the present study is that it addresses the relationship between EFE recognition performance and self-esteem in children placed in an anxious social situation. We predicted a low capacity to decode EFE in socially anxious children. Moreover, we hypothesised a relationship between a low self-esteem and difficulties to decode accurately EFE in an anxious social situation. Seventy children (8 – 12 years) were placed in an anxious social situation of performance in which they were instructed to count aloud backwards, beginning at 200 in increments of 13. Children assessed their emotional feeling state, including their degree of anxiety, before and after the anxious social situation. Furthermore, children were assessed on an EFE decoding test consisting of 16 photographs depicting EFE of happiness, anger, disgust, and sadness. For each photograph, they evaluated the presence of nine types of emotions on a 7-point Likert scale. They also completed the Self-Perception Profile for Children (Harter, 1985). No correlations emerged between the accuracy of EFE recognition and an increase of anxious feelings after the anxious social situation. However, self-esteem was correlated with performance on the EFE recognition test, r (70) = -.33, p < .01. Moreover, the lower the child’s level of self-esteem was, the more he/she perceived negative emotions (fear, anger, disgust, and shame) in EFE of anger. In conclusion, social anxiety doesn’t seem to interfere with EFE recognition performance in an anxious social situation. However, low level of self-esteem in children appears to be associated with deficits and interpretative bias in EFE recognition in an anxious social situation. The recognition of the expression of anger, an emotion socially threatening, seems particularly biased in children with low level of self-esteem. [less ▲]

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See detailCapacities of cognitive and emotional empathy in relationship to interpersonal difficulties in alcohol dependant patients (AD)
Dethier, Marie ULg; Blairy, Sylvie ULg

Poster (2010, June 04)

The term empathy refers to two related human abilities: mental perspective taking (cognitive empathy) and the vicarious sharing of emotions (emotional empathy). The main object of this study was to ... [more ▼]

The term empathy refers to two related human abilities: mental perspective taking (cognitive empathy) and the vicarious sharing of emotions (emotional empathy). The main object of this study was to explore the relationship between capacities of both aspects of empathy and their relationships with interpersonal difficulties in alcohol-dependant patients (AD). The research in alcoholism empathy has focalised around one aspect of cognitive empathy - the capacity to infer an emotional state-, and that essentially on the basis of emotional facial expression (EFE) recognition. However, researchers have shown little interest in the investigation of the other aspects of cognitive empathy. The present study focuses on the capacity to infer interpersonal intentions and on emotional empathy. As documented by the research on EFE decoding, AD patients show deficits in cognitive empathy. In this study, we investigated their capacity to infer interpersonal intentions in social situation. We hypothesized that AD patients compared to healthy individuals and to depressed patients will attributed more intentions of reject and of aggressiveness to other people on the basis of their EFE. In this study, emotional empathy was defined as the modulation of the emotional feeling state of the participant in function of the EFE display by other people. We hypothesized that the modulation in AD patient will be different from the one of healthy people in function of the Cloninger subtype of alcoholism (Cloninger, Bohman, Sigvardsson, 1987). This emotional reactivity will be more important in Type II alcoholism and less important in Type I alcoholism. As Mimicry facilitates feelings of empathy in healthy people, it was also investigated. Twenty type I AD patients, 20 type II AD patients, 20 depressed patients, and 20 healthy subjects participated to the study. The alcoholism subtype identification was maid according to the criteria from von Knorring, Bohman, von Knorring, and Oreland (1985). The participant completed questionnaires assessing the quality of interpersonal relationships, their usual quantity of alcohol consumption, and, for AD patients, their level of alcohol dependence. Their capacity to recognise faces was evaluated by the Benton facial recognition test. The empathy tasks were computerized. In the cognitive empathy task, the participants had to evaluate the adequacy (in a 7-point Likert scale) between a film of a face changing from a neutral EFE to an emotional EFE (the photographs come from the material of Matsumoto & Ekman, 1988) and an adjective descriptive of personality. Each adjective was weighted on the interpersonal dimensions of reject, aggressiveness, dominance, and affiliation. In the emotional empathy task, the participants had to evaluate their own emotional feeling state (in a 7-point Likert scale; from very negative to very positive) after watching a series of films depicting emotional faces (same material as before). During this task, the participant’s face was filmed in order to assess mimicry. The differences of empathy capacities between AD patients and control participants (depressed and healthy) are discussed in reference to the characteristics of their interpersonal relationship. [less ▲]

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See detailA ‘cook book’ method for dioxin & PCBs analysis
Focant, Jean-François ULg; Shirkhan; Patterson Jr

Poster (2010, June)

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See detailInfluence of the matrix on the In Source Decay of permethylated glycans during MALDI-TOF analysis
Smargiasso, Nicolas ULg; De Pauw, Edwin ULg

Poster (2010, June)

Introduction In source decay (ISD) is a common phenomenon occurring very rapidly during ionization process in the source of MALDI-MS instruments and resulting in the presence of well resolved peaks of ... [more ▼]

Introduction In source decay (ISD) is a common phenomenon occurring very rapidly during ionization process in the source of MALDI-MS instruments and resulting in the presence of well resolved peaks of fragments in mass spectrum. While they make interpretation of spectra more complex, these fragments were shown to be useful to sequence peptides and proteins. Concerning glycans, only a few reports were published, using different matrices on various samples and therefore making it difficult to compare. In this context, the goal of this work is to perform a systematic study allowing to define optimal conditions to induce ISD of glycans or, inversely, to minimize this phenomenon in the study of more complex mixtures. Methods Glycans were purchased from Sigma-Aldrich. Iodomethane was used in DMSO/NaOH to permethylate the glycans. This reaction was stopped by water and permethylated glycans were extracted by chloroform. Spectra were recorded on a Bruker Ultraflex II in positive ion mode. 2,5-dihydroxybenzoic acid (DHB) and 6-aza-2-thiothymine (ATT) were prepared at 20 mg/ml in 50 % acetonitrile, 0.1 % formic acid solution. 9-aminoacridine (9-AA) was dissolved at saturation in a 50 % acetonitrile, 0.1 % formic acid and further diluted 4 times in the same solution. α-Cyano-4-hydroxycinnamic (HCCA) acid was prepared at 20 mg/ml in 97 % acetone, 0,1 % formic acid. In some spots, LiI was added to obtain Li+ adducts instead of Na+ adducts. Preliminary data In source fragmentation of permethylated Lacto-N-difucoHexaose I and LS tetrasaccharide B was first studied in DHB. While the MS/MS of the Na+ adducts of these compounds (performed by LID) produces intenses B and Y fragments, those resulting from in source fragmentation are mainly oxonium ions, resulting from the cleavage of a glycosylic bond without any exchange of hydrogen atoms. These oxonium fragments were also obtained for lithium adducts. It was previously described that these fragments are produced by the cleavage of a protonated glycosidic bond. These ions carry their positive charge on a trivalent oxygen atom and are therefore not present on the spectra as sodium adducts. Since the peaks of protonated glycans are very low in MALDI spectra, it would indicate that protonation of glycosidic bonds of permethylated glycans would strongly favor a fragmentation reaction. Different matrices were tested to compare their ability to induce in source fragmentation of permethylated glycans. Interestingly, ATT gave similar results comparing to DHB while HCCA showed a lesser ability to promote in source fragmentation. However, the most striking result came from the use of 9-AA. This matrix, which is usually used in negative ion mode, was able to produce easily sodium adducts ions of permethylated glycan with a satisfying signal to noise ratio in positive ion mode. Moreover, practically no in source fragmentation was observed with this matrix. The few produced fragments were B ions but no oxonium ions were detected. Presence of these B fragments was increased for Li+ adducts. As 9-AA is the most basic of tested matrices, the absence of oxonium ions could result from its inability to transfer protons to the glycosidic bond of permethylated glycans. 9-AA could therefore become a matrix of choice to study complex mixtures of glycans, by reducing artefact peaks produced by ISD. Novel aspect ISD of permethylated glycans is induced by DHB while 9-AA strongly favors the presence of molecular ions. [less ▲]

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See detailOvergenerality Bias and these Consequences in Borderline Personality Disorder.
Boulanger, Marie ULg; Smets, Virginie; Blairy, Sylvie ULg

Poster (2010, June)

Objective: The present study investigated the Autobiographical Memory (AM) in borderline disorder population. AM is an entity that encompasses the individuals’past personnal experiences. Previous ... [more ▼]

Objective: The present study investigated the Autobiographical Memory (AM) in borderline disorder population. AM is an entity that encompasses the individuals’past personnal experiences. Previous researches have shown disturbances in AM among several psychiatric disorders such as depression, schizophrenia and bipolar disorder. This disturbances take the overgeneral retrieving form. Thus, when patients were asked to retrieve a specific event located in time and place, they recalled an overgeneral event. This deficit is not an isolated phenomen. Indeed the researches showed that AM deficits is related to decreasing of the ability to solve interpersonnal problem (Evans et al., 1992; Goddard et al., 1996) and impairments to project onself into the specific future events (D’argembeau et al., 2008; Williams et al., 1996). Impairments to respond adequately to social problems or to concrete plans for the future create hopelessness and to contribute to suicide attempt (Arie et al., 2008). Given the high risk of suicide or suicide attempts present in the Bordeline Personnality Disorder (BPD), consideration of AM in this population is appropriate. The aim of the present study was investigate the AM, the projection into the future and the problem solving in patients suffering from BPD. Method: 21 subjects BPD and 21 healthy controls participated in this study. First, the participants were asked to complete TeMA (validated French versions of AMT by Neumann & Philippot, 2006). Participants were instructed to generate specific past and future memories in response to cues words. Secondly, they were had to complete the OTT, they were asked to yield the most solutions as possible to daily problems. Finally the depression was controlled as well as neuropsychological variables. Results: The subjects with BPD recalled less specific past events and imagined less specific future events than healthy subjects (t(40) = 2.21, p = .031; t(40) = 3.4, p = .001, respectively). In addition, the number of past and future specific events was marginally correlated (r(42) = .31, p = .051). However, no difference between two groups on OTT and no correlation between past specificity and problem solving emerged. Discussion: As other clinical populations, the subjects with a BPD encounter deficits to retrieve specific past events. Moreover, these impairments are associated with deficits to imagine specific future events. Nevertheless, the ability to generate specific events was not related to the ability to solve problem. The observation of reduced specificity in the generation of autobiographical material is particularly clinically relevant. Indeed, difficulty in imagining the future may contribute to relapse. In conclusion, more systematic measure of this ability should be taken in both research and clinical fields. [less ▲]

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See detailpCO2 dynamics and related airice CO2 fluxes during sea-ice growth and decay in an ice-tank experiment
Delille, Bruno ULg; Thomas, D. N.; Dieckmann, Gerhard et al

Poster (2010, June)

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See detailKraft RB : classification of relevant variables with Random Forests
Sainlez, Matthieu ULg

Poster (2010, June)

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See detailNREM slow wave oscillation rebound after sleep deprivation : effect of aging
Lafortune, M; Viens, I; Poirier, G et al

Poster (2010, June)

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See detailThe Venus OH Nightglow Distribution
Soret, Lauriane ULg; Gérard, Jean-Claude ULg; Piccioni, Giuseppe et al

Poster (2010, June)

The first identification of the OH airglow in the terrestrial mesosphere was made in 1950 by Meinel [1950]. Recently, the unexpected presence of the OH nightglow was observed in the Venus mesosphere by ... [more ▼]

The first identification of the OH airglow in the terrestrial mesosphere was made in 1950 by Meinel [1950]. Recently, the unexpected presence of the OH nightglow was observed in the Venus mesosphere by Piccioni et al. [2008] using a limb profile from the Visible and Infra-Red Thermal Imaging Spectrometer (VIRTIS) instrument on board the Venus Express spacecraft. They clearly identified the (1-0) and (2-1) transitions at 2.80 and 2.94 µm, respectively and the (2-0) band at 1.43 µm. Additional bands belonging to the Δv=1 sequence also appear to be present longward of the (1-0) band. In a preliminary study of characteristics of the OH emission distribution, Gérard et al. [2010] pointed out a correlation between the OH(Δv=1) and the O2(a1Δ) nightglow intensities. In Soret et al. [2010], the full dataset of VIRTIS-M limb observations of the OH Venus nightglow has been corrected from the thermal emission of the planet and analyzed to determine its characteristics. Based on 3328 limb profiles, the study shows that the emission is highly variable. No clear dependence of the airglow layer altitude versus the antisolar angle is established. The peak brightness appears to decrease away from the antisolar point even if the variability at a given location is very strong. Some correlation between simultaneous observations of the intensity of the OH and the O2(a1∆) emissions has also been detected, presumably because atomic oxygen is a common precursor to the formation of O2(a1∆) and O3, whose reaction with H produces excited OH. A relation given in the one-dimensional photochemical model of Krasnopolsky [2009] has been used to link the OH and the O2(a1∆) airglows through the hydrogen flux at 130 km. It appeared that using a constant flux did not fill well the simultaneous OH and O2 observations. Either the flux has to vary with the distance to the antisolar point or other dimensions have to be involved. [less ▲]

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See detailVHHs as model proteins to investigate amyloid fibril formation: Fibril stability and effect of seeding and cross-seeding on aggregation kinectics
Chavignon, Chloé ULg

Poster (2010, June)

The term "amyloidosis" covers a group of diseases associated with the deposition of protein aggregates organized into amyloid fibrils in different organs. About forty amyloidosis are known so far, amongst ... [more ▼]

The term "amyloidosis" covers a group of diseases associated with the deposition of protein aggregates organized into amyloid fibrils in different organs. About forty amyloidosis are known so far, amongst which Alzheimer's disease, type II diabetes and immunoglobulin amyloidosis [1]. Although the mechanism of amyloid fibrils formation at the molecular level is not yet completely understood, it has been shown that the capacity to form amyloid fibrils in vitro is an intrinsic property of all polypeptide chains [1]. The choice of model proteins to investigate the aggregation process in vitro is therefore no more restrained to proteins involved in amyloidosis but can be settled on a wide variety of proteins. In this study, we have chosen to investigate the mechanism of amyloid fibrils formation by two variable domains of camelid heavy-chain antibodies (referred to as VHHs or nanobodies), cAb-HuL6 and cAb-BcII10, and this choice was motivated by the following reasons: - First, VHHs are small monomeric proteins (~14 kDa) presenting a high stability and a high solubility [2], which permits their expression with a high yield (20-40 mg.L-1). - Second, a wide range of stable mutants of these two VHHs is available. Mutations located at the disulfide bond [3,4], the CDRs [3] and the framework have been introduced. Characterisation of the aggregating properties of these mutants will allow the investigation of the impact of these structural elements on the process of fibril formation. In order to determine conditions in which cAb-HuL6 and cAb-BcII10 are more susceptible to form intermediates and thus amyloid fibrils, heat-induced unfolding experiments at pHs comprised in a range from 2,5 to 9,5 have been monitored by intrinsic fluorescence, ANS binding and circular dichroism. Then, aggregation experiments have been performed in the selected conditions and the presence of amyloid fibrils has been acknowledged by thioflavineT fluorescence experiments and electronic microscopy. We will discuss the kinetics of aggregation obtained in the absence and the presence of seeding/cross-seeding. [1] Chiti and Dobson, Annu. Rev. Biochem., 75, 2006, 333-366. [2] Dumoulin et al., Protein Sci., 11, 2002, 500-515. [3] Saerens et al., J. Mol. Biol., 352, 2005, 597-607. [4] Saerens et al., J. Mol. Biol., 377, 2008, 478-488. [less ▲]

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See detailImpact of morphosyntactic complexity in sentence comprehension in children with SLI
Leclercq, Anne-Lise ULg; Majerus, Steve ULg; Jacob, Laura et al

Poster (2010, June)

Detailed reference viewed: 104 (9 ULg)
See detailA proxy tool-box for assessing southern ocean biological carbon pump efficiency.
Dehairs, F.; Cardinal, D.; Cavagna, A.-J. et al

Poster (2010, June)

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See detailBrain-computer interface in disorders of consciousness: answering simple questions with a P3 speller
Noirhomme, Quentin ULg; Chatelle, Camille ULg; Kleih, Sonja et al

Poster (2010, June)

Objective: In the recovery from coma, the acquisition of command following represents an important milestone, indicating emergence from the vegetative state (Schnakers et al., 2009). In some patients ... [more ▼]

Objective: In the recovery from coma, the acquisition of command following represents an important milestone, indicating emergence from the vegetative state (Schnakers et al., 2009). In some patients, recovery of consciousness may precede motor recovery. Brain-computer interfaces (BCI) might permit these patients to show non-motor dependent signs of awareness and in a next step might enable communication. This study aimed at testing to what extent an EEG-based BCI could help detecting signs of awareness and communication in disorders of consciousness. We employed a P300 based BCI where healthy volunteers and patients with locked-in syndrome and in a minimally conscious state were asked to answer yes or no to simple questions by paying attention to one out of four auditorily presented stimuli (‘yes’, ‘no’, ‘stop’, ‘go’). Methods: We studied 13 patients with a minimally conscious state (MCS, 5 TBI – 8 anoxic, mean time post injury 70±109 months; mean age 42 ± 21) and 2 in pseudo-coma or locked in syndrome (LIS; brainstem stroke, time post injury 26 and 46 months; aged 63 and 29)) and 16 healthy controls (aged 45±19). Patients were evaluated using the Coma Recovery Scale Revised (CRS-R). An auditory P300 four choice speller paradigm (Furdea et al., 2009) based on the BCI2000 system (Schalk et al., 2004) was used. 16-Channel EEG was recorded using a g.tec USBAmp amplifier. A trial constituted of 15 presentation of four sounds the order of presentation being pseudo-randomized (sound duration: ~400ms; inter-stimulus interval: ~600ms). After a training session of 4 trials, patients and healthy subjects were required to answer 10 or 12 questions, respectively. Questions were of the following kind: “Is your name Quentin?”, “Is your mother’s name Dorothée?”. A stepwise linear discriminant analysis based on the training session was used to classify the data and to provide online feedback. Offline, all training and testing sequences were pooled. Sequences with artifacts were discarded and a leave-one-out approach was used to classify the data. Results: Healthy subjects presented a mean correct response rate of 73% online and 93% offline. Note that online classification failed for one control subject due to a presumed change in cognitive strategy between training and testing sessions. LIS patients showed a correct response rate of 30 and 60% (online) and 36 and 79% (offline). Three MCS patients had a correct response rate of ≥50% offline (10, 18, 0% online and 50, 53, 57% offline). Two of these three patients did not show any command following at the bedside. The 10 remaining MCS cases showed online and offline correct answers <50% (mean 33±9% online and 25±13% offline). Conclusion: Our auditory P300-based BCI permitted functional interactive communication in 15/16 controls (online) and in all offline. Our data obtained in patients with locked-in syndrome and disorders of consciousness demonstrate the potential clinical usefulness of the technique following coma but also show lower accuracy in patients as compared to healthy volunteers. This might be due to fluctuating attentional levels and exhaustibility in the MCS and to the suboptimal EEG recording quality due to movement, ocular and respiration artifacts in these challenging patients. Further algorithmic developments should include automatic artifact detection and single trial classification. Despite the need for further improvement in BCI devices adapted to post-coma patients, our results already indicate that MCS patients without any clinical sign of command-following can employ a yes-no speller offering the hope of functional interactive communication and a possibility for decision making and autonomy. Bibliography Furdea A, Halder S, Krusienski DJ, Bross D, Nijboer F, Birbaumer N, Kübler A, 2009, An auditory oddball (P300) spelling system for brain-computer interfaces, Psychophysiology. May; 46(3):617-25. Schalk G., McFarland D.J., Hinterberger T., Birbaumer N., and Wolpaw J.R. 2004, BCI2000: A General-Purpose Brain-Computer Interface (BCI) System, IEEE Trans Biomed Eng, 51(6). Schnakers C, Vanhaudenhuyse A, Giacino J, Ventura; Boly M, Majerus S, Moonen G, Laureys S, 2009, Diagnostic accuracy of the vegetative and minimally conscious state: Clinical consensus versus standardized neurobehavioral assessment, BMC Neurology, 9 (35). [less ▲]

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See detailClick chemistry : radiolabelling of oligonucleotides with fluorine- 18 for PET
Kaisin, Geoffroy ULg; Flagothier, Jessica ULg; Mercier, Frédéric ULg et al

Poster (2010, June)

Oligonucleotides (ONs), especially small interfering RNA (siRNA), are promising therapeutic agents, but their pharmacokinetics and biodistributions are widely unknown. Positron Emission Tomography (PET ... [more ▼]

Oligonucleotides (ONs), especially small interfering RNA (siRNA), are promising therapeutic agents, but their pharmacokinetics and biodistributions are widely unknown. Positron Emission Tomography (PET) using fluorine-18 is a suitable technique to image and quantify such biological processes. The challenge for the radiochemist is to introduce this short half-life isotope (t1/2(18F)=109.7 min) onto oligonucleotides or, more generally, biomolecules. The most common technique requires the coupling of a prosthetic group bearing the radiotracer with the biomolecule. Current methods for labeling ONs with fluorine-18 have sub-optimal yields and require a long synthesis time.1 Click chemistry, e.g. 1,3-dipolar Huisgen cycloaddition of azides to alkynes, could be an efficient way to increase yields and reduce synthesis time. Conjugations with ONs are usually performed at 3’-ends using a well-chosen linker in order to limit degradation by exonucleases and to avoid alteration of hybridization properties and siRNA gene silencing efficiency. This also allows the development of universal solid supports used for the solidphase synthesis of ONs. Here we report the synthesis of three alkyne-bearing linkers , the synthesis and radiosynthesis of the complementary azido-bearing prosthetic groups (1-(azidomethyl)-4-[18F]- fluorobenzene) and coupling with functionalized ONs. [less ▲]

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See detailAutomated radiosynthesis of [18F]MPPF derivatives for imaging 5-HT1A receptors
Goblet, David ULg; Thonon, David ULg; Plenevaux, Alain ULg et al

Poster (2010, May 30)

TOPIC: Molecular Neuroimaging: from Bench to Bedside Automated radiosynthesis of [18F]MPPF derivatives for imaging 5-HT1A receptors Introduction: Dysfunction of the cerebral serotoninergic system is ... [more ▼]

TOPIC: Molecular Neuroimaging: from Bench to Bedside Automated radiosynthesis of [18F]MPPF derivatives for imaging 5-HT1A receptors Introduction: Dysfunction of the cerebral serotoninergic system is implicated in numerous neurodegenerative disorders such as Alzheimer disease’s, dementia, depression, anxiety, schizophrenia, and Parkinson disease’s. The 5-HT1A serotonin receptors are involved in several physiological functions including sleep, mood, neurogenesis and learning [1]. Consequently, there have been huge efforts in finding ligands for this receptor. [11C]WAY-100635 is a high affinity radioligand used for quantifying serotonin 5-HT1A receptors with positron emission tomography. An 18F-labeled radioligand is advantageous because of higher specific activity and physical/nuclear properties (t1/2= 109 min, 97% of positron decay and positron energy of 635 keV maximum). [18F]MPPF, a selective 5-HT1A antagonist derived from WAY-100635, is currently one of the most successful PET ligand used for 5-HT1A receptor imaging [2]. However the affinity is lower then WAY-100635 and the amount of [18F]MPPF reaching the brain is relatively low since MPPF is a substrate for p-glycoprotein [3]. Methods: In order to improve the brain uptake of the radiotracer, a desmethylated analog has been developed in our lab and preliminary in vitro studies show positive results [4]. Nevertheless, the radiosynthesis take place in two steps as a protecting group removal is needed. A one step procedure with a MPPF derivative could be of very great interest. We have synthesized many MPPF derivatives in our lab (modification on the phenylpiperazine moiety) and developed an automated radiosynthesis procedure for the production of these radiotracers. [18F]MPPF was chosen as the model compound. We used a GE Healthcare FASTlabTM module and made modifications to the [18F]FDG synthesis sequence and cassette. [18F]MPPF was synthesized by coupling of [18F]FBA with the corresponding amine. After coupling, the crude solution was diluted with water and passed through a tC18 cartridge for prepurification. After elution, the [18F]MPPF was purified by semi-preparative HPLC. Results: Total synthesis time, including purification was approximately 100 min. [18F]FBA and [18F]MPPF were obtained at a corrected yield of 55% (n=20) and 25% (n=5) respectively. The radiochemical purity, checked by radio-TLC and UPLC, was >95%. Conclusions: We have developed an automated method for [18F]MPPF and derivatives production using a commercial synthesizer (FASTlabTM from GE Healthcare) and a conventional HPLC system resulting in good yields and high (radio)chemical purity. By simply switching the vial containing the modified amine, an 18F-labeled MPPF derivative could be obtained. Radiosynthesis is still under optimization and the radiotracers synthesized need to be tested as suitable 5-HT1A radioligands. Acknowledgement: This work was supported by the Fondation Rahier. References: [1] Filip M., Bader M. et Al, Pharmacol Rep. 2009 Sep-Oct; 61(5):761-77 [2] Aznavour N, Zimmer L. Et Al, Neuropharmacology. 2007 Mar; 52(3):695-707 [3] Laćan G., Plenevaux A. et Al, Eur J Nucl Med Mol Imaging. 2008 Dec;35(12):2256-66 [4] Defraiteur C., Plenevaux A. et Al., Br J Pharmacol. 2007 Nov; 152(6):952-8 [less ▲]

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See detailIs Anosognosia in Alzheimer disease also observed for behavioural and personality changes?
Feyers, Dorothée ULg; Bastin, Christine ULg; Jaspar, Mathieu ULg et al

Poster (2010, May 28)

Anosognosia is a frequent manifestation in Alzheimer disease (AD) but its extent is not yet clearly established. While anosognosia for memory deficit has been widely reported, no study has simultaneously ... [more ▼]

Anosognosia is a frequent manifestation in Alzheimer disease (AD) but its extent is not yet clearly established. While anosognosia for memory deficit has been widely reported, no study has simultaneously explored anosognosia for personality and behaviour changes. We have tackled this question with 20 AD patients and 20 matched elderly subjects (ES). Participants (AD and ES) assessed their personality and their reactions in social situation both in current (S1) and past (S1_bef) time period. Assessment of these characteristics was also performed by relatives of the participants (R2 and R2_bef). Mann-Whitney test (p<0.05) were performed between discrepancy scores (calculated by comparing answers of subjects and relatives) obtained for AD and ES. A specific measure of anosognosia was also calculated by comparing S1 and R2. Statistical analyses demonstrated (1) that relatives of AD patients report more personality and behavioural changes across time (S1-S1_bef) than relatives of ES (R2–R2_bef); (2) that self-reported changes were not significantly different between AD patients and ES; (3) that anosognosia (S1-R2) was observed in AD patients for personality changes only. Results obtained support the hypothesis that anosognosia does not affect all domain in AD. Indeed, even if AD patients are no more able to assess their current personality, they perceive adequately their current reactions in social situations. [less ▲]

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See detailUsing phenomenology and mindset induction to assess the prospective function of mind-wandering
Stawarczyk, David ULg; Majerus, Steve ULg; D'Argembeau, Arnaud ULg

Poster (2010, May 28)

A notable feature of the human cognitive apparatus resides in its propensity to spontaneously generate thoughts uncoupled from the “here and now”. An important function of these cognitions, often referred ... [more ▼]

A notable feature of the human cognitive apparatus resides in its propensity to spontaneously generate thoughts uncoupled from the “here and now”. An important function of these cognitions, often referred to as mind-wandering, might be to create and/or update scripts, schemata, and future plans in long-term memory. In this study, we investigated this hypothesis by examining whether priming personal projects influenced the occurrence and characteristics of mind-wandering episodes during a subsequent, unrelated cognitive task, as assessed with an experience sampling method. We found that inducing particular mindsets that were related to personal goals (i.e., writing an essay about one’s personal projects) in comparison to a control baseline condition (i.e., writing an essay about a familiar itinerary) increased the number of future-oriented mind-wandering reports while participants performed the Sustained Attention to Response Task (SART). Furthermore, participants judged most of these thoughts as having a future-oriented function (i.e., they were related to planning, decision making, or reevaluating situations). Finally, as behavioral validation of participants’ subjective reports, we found that mind-wandering was positively linked with intra-individual variability (IIV) in response times, whereas reports of being concentrated on the SART were negatively linked with IIV. These data support the view that an important function of mind-wandering resides in the anticipation and planning of the future. [less ▲]

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