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See detailHemoreactivity of poly (dimethyl-aminoethyl-methacrylate) designed for the production of stealth red blood cells
Cerda, B; Pérez, E; Flores, H et al

Poster (2009, April 01)

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See detailDetermination of phospholipids extracted from Tsukamurella paurometabola C-924 after freeze-drying and during the subsequent storage.
Coulibaly, Ibourahema ULg; Yao, Amenan Anastasie ULg; Dubois Dauphin, Robin ULg et al

Poster (2009, April 01)

The total lipids of Tsukamurella paurometabola C-924 were analysed after freeze-drying. Seven individual lipids classes were identified namly neutral lipids (NLs), fatty acids (FAs), phospholipids (PLs ... [more ▼]

The total lipids of Tsukamurella paurometabola C-924 were analysed after freeze-drying. Seven individual lipids classes were identified namly neutral lipids (NLs), fatty acids (FAs), phospholipids (PLs), sterol ester (SEs), triglycerides (TGs), diglycerides (DGs) and monoglycerides (MGs). The principal fatty acids identified in most lipid classes were palmitic (C16:0), palmitoleic (C16:1), oleic (C18:1), linoleic (C18:2), and linolenic (C18:3). PLs were the major constituents and accounted for 50-60% of the total lipids. PLs were fractionated. . PLs of Tsukamurella paurometabola content phosphatidic acid (PA), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylcholine (PC), sphingomyelin (SM), lysophosphatidylcholine (LPC) and phosphatidylglycerol (PG). It was observed that PG had the highest proportion at most points relative to other PLs and was the predominant component of PLs (30%-56%). Evolution of individual rate was followed during stored at 20°C and 40°C with or without lithothamne400®, respectively. [less ▲]

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See detailPhysico-chemical characterization of new polyhydroxyburates (PHB).
Ottevaere, M; Lespineux, David; Sevrin, Chantal ULg et al

Poster (2009, April 01)

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See detailPreparations and characterisations of semi-solid formulations containing a hydrophilic drug for vaginal administration
Coia, Isabelle ULg; Evrard, Brigitte ULg; Piette, Marie ULg

Poster (2009, April 01)

The purpose of this study is to demonstrate the effect of different types of semi-solid formulations (aqueous gels, liquid jellified emulsions and hydrophilic or lipophilic creams) for vaginal ... [more ▼]

The purpose of this study is to demonstrate the effect of different types of semi-solid formulations (aqueous gels, liquid jellified emulsions and hydrophilic or lipophilic creams) for vaginal administration on the release kinetic of a hydrophilic drug. This drug is an acidic and hydrophilic (log P (octanol/water) = -3.3) molecule with an aqueous solubility upper than 170mg/ml at pH 6-8. The formulations characterisations consisted in the in vitro evaluation of the drug release kinetic and the measure of all formulations viscosity as well as the creams stability and emulsions droplets size. [less ▲]

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See detailChronologie de l’architecture médiévale : application à l’église Saint-Irénée de Lyon (69)
Bouvier, Armel; Reynaud, Jean-François; Guibert, Pierre et al

Poster (2009, April)

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See detailCycles in the Temperature Data Are Induced by the Sun
Nicolay, Samuel ULg; Mabille, Georges ULg; Fettweis, Xavier ULg et al

Poster (2009, April)

The presence of two cycles of period of 30 and 42 months approximatively has been observed in temperature records and climatic indices. Moreover, it has been shown that these cycles are statistically ... [more ▼]

The presence of two cycles of period of 30 and 42 months approximatively has been observed in temperature records and climatic indices. Moreover, it has been shown that these cycles are statistically significant. Here we outline the role played by the Sun in the presence of these cycles, observed in time series. To do so, we use IPCC AR4 climatic models, sunspot number data and the Morlet wavelet method. [less ▲]

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See detailEffects of consolidation of procedural motor memory traces on slow and fast spindles
Barakat, M; Doyon, J; Debas, K et al

Poster (2009, April)

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See detailCO2 fluxes exchanged by a 4-year crop rotation cycle
Aubinet, Marc ULg; Moureaux, Christine ULg; Bodson, Bernard ULg et al

Poster (2009, April)

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See detailN-REM sleep slow oscillations amplitude and density in the young and middle-aged men and women
Viens, I; Lafortune, M; Poirier, G et al

Poster (2009, April)

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See detailExperimental evaluation of flux footprint by natural tracer experiment
Arriga, N.; Aubinet, Marc ULg; Carrara, A. et al

Poster (2009, April)

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See detailEffects of aging and daytime recovery sleep on N-REM slow oscillations
Lafortune, M; Viens, I; Poirier, J et al

Poster (2009, April)

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See detailDetermination of isotopic fractionation delta13C of methane from ground-based FTIR observations performed at the Jungfraujoch
Duchatelet, Pierre ULg; Mahieu, Emmanuel ULg; Sussmann, Ralf et al

Poster (2009, April)

Atmospheric methane (CH4) is a strong greenhouse gas that has important chemical impacts on both the troposphere and the stratosphere. In the troposphere, oxidation of methane is a major regulator of OH ... [more ▼]

Atmospheric methane (CH4) is a strong greenhouse gas that has important chemical impacts on both the troposphere and the stratosphere. In the troposphere, oxidation of methane is a major regulator of OH and is a source of formaldehyde, carbon monoxide and hydrogen. In the stratosphere, CH4 plays a central role (i), due to its contribution to the stratospheric water vapor budget, and (ii), as a sink for chlorine atoms which reduces the rate of stratospheric ozone depletion. Because the different sources of methane (natural and anthropogenic like wetlands, rice paddies, termites, natural gas escape, biomass burning, etc) have distinct 13C/12C ratios (usually reported in “delta” notation δ13C), measurements of atmospheric 13CH4 content, in addition to those of the main isotopologue (12CH4), can be used to investigate individual source strengths as well as their spatial and temporal distributions. Characterization of the isotopic fractionation of methane is therefore important, for example, to help models constrain estimates of the global methane budget. However, experimental data for the 13C/12C isotope ratio are sparse. The currently accepted average value of δ13C in atmospheric methane is about -47‰ (Platt et al., 2004). The first goal of this work is to develop and to characterize (in terms of information content and error budget) an original retrieval approach to derive 13CH4 columns from ground-based Fourier transform infrared (FTIR) spectra recorded at the International Scientific Station of the Jungfraujoch (ISSJ; 46.5°N, 8.0°E, 3580m a.s.l., Swiss Alps). The retrieval strategy is based on a Tikhonov L1 approach which has been originally developed for 12CH4 by Sussmann et al. (2008) [see also contributions by Sussmann et al. to this conference (EGU2009-7869)]. In order to validate our 13CH4 products, comparisons with satellite ACE-FTS (Atmospheric Chemistry Experiment - Fourier Transform Spectrometer) measurements are performed. Then, atmospheric δ13C ratios derived from the FTIR measurements will be compared to values published in the literature and critically discussed. References: Platt, U., W. Allan and D. Lowe, Hemispheric average Cl atom concentration from 13C/12C ratios in atmospheric methane, Atmos. Chem. Phys., 4, 2393-2399, 2004. Sussmann, R., Forster, F., Borsdorff, T., et al.: Satellite validation of column-averaged methane on global scale: ground-based data from 15 FTIR stations versus last generation ENVISAT/SCIAMACHY retrievals, IGAC 10th International Conference, Annecy, France, 7-12 Sep 2008. [less ▲]

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See detailGreenland ice sheet projections from IPCC AR4 global models
Franco, Bruno ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg et al

Poster (2009, April)

The atmosphere-ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most efficient ... [more ▼]

The atmosphere-ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most efficient AOGCMs are chosen by comparison between the 1970-1999 outputs of the Climate of the twentieth Century experiment (20C3M) and reanalyses (ECMWF, NCEP/NCAR). This comparison reveals that surface parameters such as temperature and precipitation are highly correlated to the atmospheric circulation (500 hPa geopotential height) and its interannual variability (North Atlantic oscillation). The outputs of the three most efficient AOGCMs are then used to assess the changes planned by three IPCC greenhouse gas emissions scenarios (SRES) for the 2070-2099 period. Future atmospheric circulation changes should dampen the west-to-east circulation (zonal flow) and should enhance the Meridional Overturning Circulation (MOC). As a consequence, this provides more heat and moisture to the GrIS, increasing temperature on the whole ice sheet and precipitation on the north-eastern region. It is also shown that the GrIS surface mass balance (SMB) anomalies from the SRES A1B scenario are about -300 km³/yr with respect to the 1970-1999 period, leading to 5 cm of global sea-level rise (SLR) for the end of the 21st century. This work helps to choose the boundaries conditions for AOGCMs downscaled future projections. [less ▲]

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See detailLayer-by-layer self-assembled chitosan coating on electrospun nanofibers
Croisier, Florence ULg; Aqil, Abdelhafid ULg; Detrembleur, Christophe ULg et al

Poster (2009, April)

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well-known method for surface ... [more ▼]

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well-known method for surface coating, based on electrostatic interactions. It enables the controllable deposition of a variety of polyions including synthetic and natural materials, with designable layer structure, defined wall thickness and size. Electrospinning (ESP) technique allows the fabrication of polymer fibers ranging from nanometers to a few microns in diameter, depending on the polymer characteristics (a.o. molecular weight, solution viscosity and conductivity) and processing conditions (electric potential, distance between syringe-capillary and collection plate, concentration, flow rate). Mats of nanofibers produced by ESP display a very large surface area-to-volume ratio and high porosity with very small pore size. The nanometric scale of electrospun fibers also proves a positive effect on cellular growth, as fibers mats mimic extracellular matrix structure. The association of these two techniques with the use of biocompatible and biodegradable polymers such as chitosan, gives outstanding prospects in the field of biomedical applications, especially for the preparation of wound dressings, artificial skin or tissue engineering scaffolds. In the present study, a charged copolymer, poly(methylmethacrylate-block-methacrylic acid), was added to a poly(ε-caprolactone) or poly(D,L-lactide) solution before electrospinning in order to obtain charges on fibers surface. Oppositely charged polyelectrolytes – chitosan and poly(styrene sulfonate) or hyaluronic acid – were then alternately deposited on these aliphatic polyester fiber “cores” using LBL method. The aliphatic polyester core was also removed selectively to confirm the existence of a multilayered shell, obtaining hollow fibers. [less ▲]

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See detailEvidence of an atypical scale development during the settlement phase of a coral reef fish
Frederich, Bruno ULg; Lecchini, David; Vandewalle, Pierre ULg

Poster (2009, April)

As the majority of coral reef fishes, the Convict Surgeonfish Acanthurus triostegus (Acanthuridae) has a complex life cycle that involves an ontogenetic change in morphology, physiology and behaviour as ... [more ▼]

As the majority of coral reef fishes, the Convict Surgeonfish Acanthurus triostegus (Acanthuridae) has a complex life cycle that involves an ontogenetic change in morphology, physiology and behaviour as its pelagic larval stage colonizes the benthic habitat. Abrupt and spectacular changes in skeletal structures occurring when a fish takes on its juvenile form were highlighted in flatfish, bonefish, tarpon, eels, pearlfish and lampreys. However, few studies are devoted to the changes in skeleton during the settlement period of demersal coral reef fishes. In the present study conducted at Rangiroa Atoll (French Polynesia), we highlight an unexpected scales development in A. trisostegus during a fifteen days period just after the reef settlement. Fish was collected during the settlement and reared in aquaria. The osseous skeleton was displayed by a standard Alizarin red S staining technique. At settlement (t0) (SL = 22-25 mm), A. triostegus showed calcified and very long plates, lying in the dermis on the whole body. After three days, some small scales developed on the caudal peduncle. The plates seemed unchanged from the head to the pectoral girdle but were thinner on the trunk. The thin plates are pricked with whitish spots, which seem to indicate a poorer fixation of the alizarin corresponding to a decalcification process. Six days after the settlement, the squamation extended anteriorly to the pectoral girdle by the addition of new scales. Thin plates were always present on the head. Then the density of scales rapidly increased along the trunk during the following three days. The scales appeared on the head nine days after the settlement. Clearly, the plates do not transform into scales. The plates disappearance and the scales appearance appear as two parallel phenomena in the development. [less ▲]

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See detailConfidence Levels for the Cycles Found in Air Temperature Data
Mabille, Georges ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg et al

Poster (2009, April)

Recently, new cycles have been observed in air temperature data and proxy series using a wavelet-based methodology. Although many evidences attest the validity of this method applied to climatic data, no ... [more ▼]

Recently, new cycles have been observed in air temperature data and proxy series using a wavelet-based methodology. Although many evidences attest the validity of this method applied to climatic data, no systematic study of its efficiency has been carried out. Here, we estimate the confidence levels for this approach and show that the observed cycles are significant. [less ▲]

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See detailDétection des sapovirus porcins par RT-PCR en temps réel
Mauroy, Axel ULg; Scipioni, Alexandra; Mathijs, Elisabeth et al

Poster (2009, April)

Les sapovirus appartiennent à la famille virale des Caliciviridae. Ces virus sont responsables de gastroentérites épidémiques dans l’espèce humaine et sont actuellement majoritairement détectés en Asie ... [more ▼]

Les sapovirus appartiennent à la famille virale des Caliciviridae. Ces virus sont responsables de gastroentérites épidémiques dans l’espèce humaine et sont actuellement majoritairement détectés en Asie. Des souches de sapovirus ont également été isolées dans l’espèce porcine. Trois pays européens seulement ont rapporté la présence de souches de sapovirus porcins dans leurs troupeaux: la Hongrie (Reuter et al., 2007), l’Italie (Martella et al., 2008) et tout récemment la Belgique (Mauroy et al., 2008). La détection moléculaire de la présence de séquences de sapovirus porcins dans des pays où densités d’élevages et de population humaine se conjuguent posent des questions d’ordre zoonotique, problème déjà en discussion pour des virus qui leur sont proches: les norovirus humains et animaux (Scipioni et al., 2008). De plus l’identification de ces nouveaux pathogènes pour l’espèce porcine suggèrent également d’en évaluer les impacts économique, sanitaire et clinique pour cette filière. Ces questions ne pourront être correctement évaluées que si ces virus sont recherchés et que des méthodes fiables de détection sont développées. Dans une précédente étude (Mauroy et al., 2008), le couple d’amorce p289/p290, développé par Jiang et collaborateurs (1999) pour la détection des calicivirus humains (norovirus et sapovirus), avait permis la détection de séquences génomiques de sapovirus et de norovirus porcins. Les amorces p289/290 ont été utilisées dans cette étude dans une RT-PCR en temps réel mettant à profit la technologie SYBR green. L’étude des courbes de dissociation obtenues nous a permis de pouvoir différencier des échantillons de matières fécales positifs pour la présence de séquences génomiques de sapovirus porcins de ceux qui étaient positifs pour la présence de différents calicivirus humains ou animaux (norovirus humains, sapovirus humains, norovirus bovin et porcin, vésivirus félin isolé de tractus respiratoire, vésivirus félin isolé de tractus digestif). Cette méthode devra être dans un premier temps appliquée à un échantillon plus important de matières fécales confirmées positives pour la présence de sapovirus porcins pour pouvoir être validée. La validation de cette méthode pourra ensuite permettre aux laboratoires de diagnostic de disposer d’une méthode rapide et fiable de détection de ces virus dans les filières concernées. [less ▲]

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See detailTolerance to copper in the cuprophyte Haumaniastrum Katangense (S. Moore) P.A. Duvign. & Plancke
Chipeng, François; Colinet, Gilles ULg; Ngongo Luhembwe, Michel et al

Poster (2009, March 27)

Detailed reference viewed: 19 (2 ULg)
See detailEnvironmental Controls on the Distribution of Aquatic Macrophytes in Ugandan Crater-lakes
Lebrun, Julie ULg; Mahy, Grégory ULg

Poster (2009, March 27)

This research is part of an integrated paleoecological project which aims at coupling reconstructions of past vegetation and water-quality changes with climate variability. Crater-lakes from East Africa ... [more ▼]

This research is part of an integrated paleoecological project which aims at coupling reconstructions of past vegetation and water-quality changes with climate variability. Crater-lakes from East Africa are favourable to the conservation of proxy indicators such as plant macrofossils used to reconstruct the lake ecosystem. The study of modern macrophytic communities related to present environmental parameters was the first step of this research. Phytosociologic and environmental data were collected in 36 crater-lakes in South-western Uganda. Species abundance and habitat conditions were described in 216 relevés arranged along transects from the lakeshore to the depth limit of aquatic plant development. A cluster analysis identified 8 macrophytes communities and their indicator species were highlighted. Combining two levels of analysis (lake or relevé) with different kind of ordinations (CA and CCA), main parameters explaining community variability were conductivity, pH, Human Impact index, vegetation zonation and productivity (Chlorophyll-a and total nitrogen). Multiple species response curves to environmental parameters were performed to assess the ecological amplitude at the individual level and select species with a good proxy-indicator value. These results give some trends about the ecology of macrophytes communities and the ecological significations of macrofossils. [less ▲]

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See detailLe remembrement urbain : requalifier les quartiers, recomposer le tissu urbain
Grabczan, Robert; Marique, Anne-Françoise ULg; Meuris, Coralie et al

Poster (2009, March 24)

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See detailUtilisation des prises de vue aériennes à basse altitude pour le suivi des activités hydro-agricoles - Cas du bassin du Kou (Burkina Faso)
Wellens, Joost ULg; Diallo, Mamadou; Dakoure, Denis et al

Poster (2009, March 19)

Le bassin du Kou, situé dans le sud-ouest du Burkina Faso, est depuis quelques décennies le théâtre de différentes formes de conflits liés à toute une série de problèmes que l’on rencontre généralement ... [more ▼]

Le bassin du Kou, situé dans le sud-ouest du Burkina Faso, est depuis quelques décennies le théâtre de différentes formes de conflits liés à toute une série de problèmes que l’on rencontre généralement dans des zones irriguées. Dans le bassin du Kou, les aménagements hydro-agricoles recensés couvrent une superficie totale de près de 3.200 ha ; il s’agit pour l’essentiel de périmètres privés formant la ceinture maraîchère et horticole de Bobo- Dioulasso et d’un grand périmètre de 1.200 ha réalisé par l’Etat à Bama et spécialisé dans la production du riz. Le développement d’une filière fruits et légumes sous l’impulsion de l’initiative privée est un trait caractéristique de la production irriguée dans la région. Outre l’abondance en eau liée à la présence de sources importantes, d’une nappe phréatique facilement exploitable, d’un cours d’eau pérenne et un hivernage à caractère sub-humide, la plupart des utilisateurs d’eau se retrouvent régulièrement en pénurie d’eau suite à l’extension non contrôlée de l’agriculture irriguée. Ceci a conduit les gestionnaires du bassin à rechercher des outils de contrôle et de suivi. A partir de plus de 300 prises de vue aérienne ‘amateurs’ à basse altitude, ayant une résolution de 0,8 m., une image d’occupation détaillée des sols a pu être élaborée. Des logiciels de mosaïquage, de traitement d’images et de SIG ont permis la construction d’une seule image géoréférencée. Les parcelles agricoles irriguées ont ainsi pu être délimitées. Leurs occupations ont été comparées et complétées avec les résultats d’un recensement hydro-agricole exhaustif organisé au même moment. Cette technique permet un suivi spatial des activités agricoles à moindre coût par rapport à l’acquisition des images satellites à haute résolution. L’approche est également moins sensible aux influences atmosphériques non-prévisibles dans la programmation des images satellites. Elle répond avec une précision largement suffisante aux objectifs de suivi et contrôle des parcelles irriguées demandés par les gestionnaires du bassin. [less ▲]

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See detailThe influence of cobalt-coordination on cobalt-mediated radical polymerization of vinyl monomers
Debuigne, Antoine ULg; Piette, Yasmine ULg; Poli, Rinaldo et al

Poster (2009, March 19)

Nowadays, polymers are a part of everyday life. Researchers encouraged by growing need in high performance polymers develop new synthesis tools to manage the molecular architecture and thus the polymer ... [more ▼]

Nowadays, polymers are a part of everyday life. Researchers encouraged by growing need in high performance polymers develop new synthesis tools to manage the molecular architecture and thus the polymer properties. In this context, CRP (Controlled Radical Polymerization) techniques have been developed to obtain well-defined architectures and to control polymer parameters. Among these systems is Cobalt-Mediated Radical Polymerization (CMRP), which is based on the reversible deactivation of the growing radical chains with a cobalt complex, the cobalt (II) bis-acetylacetonate. The interest of this system is not only due to its ability to control the polymerization of very reactive monomers such as vinyl acetate (VAc) and N-vinylpyrrolidone (NVP), but also its peculiar mechanism which exhibits two pathways depending on the polymerization conditions; a reversible termination process and a degenerative chain transfer mechanism. Furthermore, it has been showed that the Co-C strength and thus the polymerization are strongly influenced by the use of some additives, such as water, dimethylformamide, dimethylsulfoxide and pyridine, which coordinate the cobalt free site. In this presentation we report the use of a preformed alkyl-cobalt(III) adduct as initiator for the polymerization of acrylonitrile (AN) and the use of these ligands in the CMRP system to synthesize well-defined poly(vinyl acetate)-b-poly(acrylonitrile) block copolymers. As a conclusion, cobalt-coordination appears today as a unique opportunity to adjust the Co-C bond strength and to push back the bounds of possibilities in terms of macromolecular engineering assisted by CMRP. [less ▲]

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

Poster (2009, March 18)

Click chemistry : radiolabelling of oligonucleotides with fluorine-18 for PET imaging Oligonucleotides (ONs), especially small interfering RNA (siRNA), are promising therapeutic agents, but their ... [more ▼]

Click chemistry : radiolabelling of oligonucleotides with fluorine-18 for PET imaging 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.{Vries2003} 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 (see Figure 1). This family of reactions are well suited to the radiolabelling of ONs as they are tolerant to a wide range of solvent and require mild reaction conditions and simple purifications.{Glaser2007} The major strength of this approach is its versatility: it can be easily transposed to any other kind of biomolecules (e.g. peptides, lipids) as long as they can bear an azido or alkyne moiety. 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.{Kurreck2009} This also allows the development of universal solid support because synthesis occurs from the 3’ to 5’-end. The linker must fulfil a number of requirements:{Gait2001} - Bearing one alkyne, one primary and one secondary alcohol moiety; - Having a well-defined and known stereochemistry. According to these terms, we propose three different potential linkers (see Figure 2) that can be incorporated into the solid-phase synthesis of ONs. Starting materials are commercially available as pure enantiomers at an affordable price. Here we report the synthesis and characterisation of an alkyne-bearing linker and the synthesis and radiosynthesis of the complementary azido-bearing prosthetic groups (1-(azidomethyl)-4-[18F]-fluorobenzene). [less ▲]

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See detailDialister Pneumosintes brain abscess
PIERART, Julie ULg

Poster (2009, March 13)

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See detailSynthesis and study of wetting and swelling behaviour of PLA-PEO-PLA and PCL-PEO-PCL copolymers
Köttgen, Cindy; Borget, P; Rouxhet, P et al

Poster (2009, March 01)

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See detailTxXIIIA, an atypical homodimeric conotoxin found in the Conus textile venom
Quinton, Loïc ULg; Gilles, Nicolas; De Pauw, Edwin ULg

Poster (2009, March)

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See detailGlucose-galactose transporter DEFICIENCY: a diagnosis based on clinical observations.
HARVENGT, Julie ULg; poskin, julie; etienne, isabelle et al

Poster (2009, March)

Dehydration and major diarrhea in young infants is mainly linked to infectious diseases. However in case leading to denutrition and growth retardation, metabolic causes or malabsorption should be evocated ... [more ▼]

Dehydration and major diarrhea in young infants is mainly linked to infectious diseases. However in case leading to denutrition and growth retardation, metabolic causes or malabsorption should be evocated. We report here the case of a few days old infant admitted for early recurrence of liquid stools and vomiting. XX is born at term (3450 grams, 51 cm) after an uneventful pregnancy. Consanguinity has been reported in the family. He was breastfed but presented rapidly liquid stools and vomiting. At 10 days old he was first admitted for dehydration, loss of weight below his birth weight (2900 grams) and severe hypernatremia. Semi elementary diet led to some improvement but he was readmitted at the age of one month for similar even worse symptoms including abdominal distension and explosive stools. Complementary investigations have excluded infection, parasitosis, malformation and immune deficits. Different diet formulas were tried with no significant benefit what led to the placement of parenteral nutrition thanks to which weight was gained. Hypothesis of peculiar carbohydrate malabsorption was made and the following tests have been carried out: -Clinitest: presence of reducing substances in the stools. -Lactose Breath test: between 15 and 90 ppm H2 with a peak value at 90 ppm H2 after 90 minutes. -Duodenal biopsy: normal histology; normal activity of lactase, maltase, saccharase-isomaltase. Considering the normality of these enzyme activities, hypothesis of “Na-dependant glucose-galactose transporter” deficit was put forward. This was confirmed according to the results of HGPO and glucose breath test. Search for SGTL1 gene mutation is still in progress. In conclusion despite of the huge progresses made at molecular biology level, clinical observation remain essential to the diagnosis of malabsorption. Precise reporting of the used milk formula and comparative analysis of their composition can orient the diagnosis and help to select the most accurate molecular test. Here, analyses exclude every enzyme activity deficiencies. Carbohydrate malabsorption from first days of live can be linked to a glucose-galactose transporter deficiency due to a SGLT1 mutation (chr 22). This autosomal recessive disorder has only been reported 200 times until now. [less ▲]

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See detailEffets de l'âge et de la privation de sommeil sur les oscillations lentes en sommeil NREM
Lafortune, M; Viens, I; Poirier, G et al

Poster (2009, March)

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See detailComparison of bovine and human O26 EHEC strains by the Whole Genome PCR Scanning
Bardiau, Marjorie ULg; Ogura, Y.; Mainil, Jacques et al

Poster (2009, March)

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See detailThe mayonnaise droplet
Terwagne, Denis ULg; Mack, Nicolas; Dorbolo, Stéphane ULg et al

Poster (2009, March)

Detailed reference viewed: 14 (3 ULg)
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See detailAir-ice CO2 fluxes in the Arctic coastal area (Amundsen Gulf)
Geilfus, Nicolas-Xavier ULg; Tison, Jean Louis; Carnat, Gauthier et al

Poster (2009, March)

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See detailLe portfolio appliqué à la formation en logopédie
Maillart, Christelle ULg; Deum, Mélanie ULg; Grevesse, Pascale ULg et al

Poster (2009, March)

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See detailPreparation of multilayered chitosan-based nanofibers by combination of electrospinning and layer-by-layer deposition techniques
Croisier, Florence ULg; Aqil, Abdelhafid ULg; Detrembleur, Christophe ULg et al

Poster (2009, March)

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well known method for surface ... [more ▼]

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well known method for surface coating, based on electrostatic interactions. It enables the controllable deposition of a variety of polyions including synthetic and natural materials, with designable layer structure, defined wall thickness and size. Electrospinning (ESP) technique allows the fabrication of polymer fibers ranging from nanometers to a few microns in diameter, depending on the polymer characteristics (a.o. molecular weight, solution viscosity and conductivity) and processing conditions (electric potential, distance between syringe-capillary and collection plate, concentration, flow rate) (3). Mats of nanofibers produced by ESP display a very large surface area-to-volume ratio and high porosity with very small pore size. The nanometric scale of electrospun fibers also proves a positive effect on cellular growth, as fibers mats mimic extracellular matrix structure. The association of these two techniques with the use of biocompatible and biodegradable polymers such as chitosan, gives outstanding prospects in the field of biomedical applications, especially for the preparation of wound dressings, artificial skin or tissue engineering scaffolds. In the present study, a charged copolymer, poly(methylmethacrylate-block-methacrylic acid), was added to a poly(ε-caprolactone) or poly(D,L-lactide) solution before electrospinning in order to obtain charges on fibers surface. Oppositely charged polyelectrolytes – chitosan and poly(styrene sulfonate) or hyaluronic acid – were then alternately deposited on these aliphatic polyester fiber “cores” using LBL method. The aliphatic polyester core was also removed selectively to confirm the existence of a multilayered shell, obtaining hollow fibers. [less ▲]

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See detailpH-sensitive micellar systems for controlled drug delivery: synthesis and structural characterization by small-angle neutron scattering
Joset, Arnaud ULg; Jérôme, Christine ULg; Brulet, Annie et al

Poster (2009, March)

The aim of the project is the preparation of micellar nanocarriers made of biocompatibles copolymers and their structural analysis by Small Angle Neutron Scattering (SANS). These micelles could be used in ... [more ▼]

The aim of the project is the preparation of micellar nanocarriers made of biocompatibles copolymers and their structural analysis by Small Angle Neutron Scattering (SANS). These micelles could be used in drug delivery applications to fight cancer1. The hydrophobic polycaprolactone (PCL) core is intended to incorporate the drug. The corona of hydrophilic polyethylene oxide (PEO) stabilizes the nanocarriers with respect to the plasma proteins. The pH in the neighborhood of the tumoral cells is lower than in the healthy cells. We incorporated a pH-sensitive sequence of poly(2-vinylpyridine) (P2VP). As a result, these micelles are expected to deliver their drug near the cancerous cells without affecting the healthy cells. When the pH is acidic, the P2VP is protonated and the chains are repulsive. The micellar size is then larger than in basic pH, when the P2VP is precipitated on the PCL core. We prepared PCL65-b-P2VP31 / PCL65-b-PEO114 and PCL32-b-P2VP52 / PCL36-b-PEO114 50:50 mixtures of diblocks copolymers. The resulting mixed micelles are analyzed by SANS. We developed a theoretical model with a spherical water-free PCL core. The PEO corona is described as consisting of gaussian chains with a thickness estimated as twice the chain gyration radius, Rg. We propose two alternatives for handling the P2VP zone. The P2VP molecules are either assumed to be Gaussian chains or they fill a shell of thickness L with possible water penetration.The fitting of the models to the experimental scattering cross sections leads to important structural parameters like the aggregation number, the core radius, the gyration radius and the thickness of the P2VP shell. [less ▲]

Detailed reference viewed: 88 (13 ULg)
See detailPhysico-chemical properties and CO2 fluxes at a frost flowers station (SIMBA Experiment - Bellingshaussen Sea, Antarctica)
Tison, Jean Louis; Brabant, Frederic; Geilfus, Nicolas-Xavier ULg et al

Poster (2009, March)

Detailed reference viewed: 15 (0 ULg)
Peer Reviewed
See detailHigh incidence of invasive group B streptococcal infections in uninfected infants born to HIV-1 mothers
Epalza, C.; Goetghebuer, T.; Hainaut, M. et al

Poster (2009, March)

Detailed reference viewed: 8 (0 ULg)
Peer Reviewed
See detailImpact of participatory risk assessment approaches on occupational health professional's attitutdes and practices Proceedings ICOH 2009
Mairiaux, Philippe ULg; Mazina, D. ULg; Roussel, Sandrine et al

Poster (2009, March)

In the last 10 years with the support of the Belgian Federal Public Service (FPS) for Employment and Labour and the European Social Fund, prevention advisors (PA) and occupational health physicians (OP ... [more ▼]

In the last 10 years with the support of the Belgian Federal Public Service (FPS) for Employment and Labour and the European Social Fund, prevention advisors (PA) and occupational health physicians (OP) have been invited to use new methods for risk assessment involving workers’ participation, namely the Sobane strategy, or the Risk/Toxtrainer methodology. This study aimed at evaluating these methods actual use among PA’s and OP’s, and its impact on representations and risk management practices. Methods A national postal survey was conducted in 2007 among a random sample (n=3340) of all professionals registered as PA (>6000) or OP (about 1000) by the FPS. The questionnaire explored those professionals’ familiarity with 12 different risk assessments methods, the nature of their interventions in enterprises, their representations about participation and collected demographic information. Results A total of 859 completed surveys (response rate: 25.7 %) could be analyzed. Among the methods studied, the Kinney-Wiruth accident risk analysis is the most familiar (54% regular users + 19% trained ones). The participatory methods are familiar (users + trained) to respectively 46 % (Sobane) and 11% (Risktrainer) of the respondents. When analyzing practices in enterprises, the professionals familiar with one of the participatory approaches are more often than the other professionals suggesting the use of participation in risk management to colleagues (84 vs 67.5% ; p<0.000) or to the employer (84 vs 73.5% ; p<0.000). Those professionals not familiar with the participatory approaches agree more often with the following statements: “PA role is more to inform than to listen” (p=0.005), “Participatory processes are raising unrealistic expectations among the staff” (p=0.002). Discussion This study shows that participatory risk assessment methods are gaining ground in Belgian enterprises. It also highlights the significant influence that information and training in those methods have had on risk management practices and the professionals’ representations. [less ▲]

Detailed reference viewed: 7 (1 ULg)
See detailDynamics of flood-freeze cycles during the SIMBA experiment (Brussels and Liège Stations - Bellingshaussen Sea, Antarctica)
Tison, Jean Louis; Brabant, Frederic; Geilfus, Nicolas-Xavier ULg et al

Poster (2009, March)

Detailed reference viewed: 16 (0 ULg)
Peer Reviewed
See detailImpact of participatory risk assessment approaches on occupational health professional's attitudes and practices
Mairiaux, Philippe ULg; Mazina, D. ULg; Roussel, Sandrine et al

Poster (2009, March)

Introduction In the last 10 years with the support of the Belgian Federal Public Service (FPS) for Employment and Labour and the European Social Fund, prevention advisors (PA) and occupational health ... [more ▼]

Introduction In the last 10 years with the support of the Belgian Federal Public Service (FPS) for Employment and Labour and the European Social Fund, prevention advisors (PA) and occupational health physicians (OP) have been invited to use new methods for risk assessment involving workers’ participation, namely the Sobane strategy, or the Risk/Toxtrainer methodology. This study aimed at evaluating these methods actual use among PA’s and OP’s, and its impact on representations and risk management practices. Methods A national postal survey was conducted in 2007 among a random sample (n=3340) of all professionals registered as PA (>6000) or OP (about 1000) by the FPS. The questionnaire explored those professionals’ familiarity with 12 different risk assessments methods, the nature of their interventions in enterprises, their representations about participation and collected demographic information. Results A total of 859 completed surveys (response rate: 25.7 %) could be analyzed. Among the methods studied, the Kinney-Wiruth accident risk analysis is the most familiar (54% regular users + 19% trained ones). The participatory methods are familiar (users + trained) to respectively 46 % (Sobane) and 11% (Risktrainer) of the respondents. When analyzing practices in enterprises, the professionals familiar with one of the participatory approaches are more often than the other professionals suggesting the use of participation in risk management to colleagues (84 vs 67.5% ; p<0.000) or to the employer (84 vs 73.5% ; p<0.000). Those professionals not familiar with the participatory approaches agree more often with the following statements: “PA role is more to inform than to listen” (p=0.005), “Participatory processes are raising unrealistic expectations among the staff” (p=0.002). Discussion This study shows that participatory risk assessment methods are gaining ground in Belgian enterprises. It also highlights the significant influence that information and training in those methods have had on risk management practices and the professionals’ representations. [less ▲]

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See detailProducing transient climate change scenarios for AquaTerra catchments
Blenkinsop, Stephen; Burton, Aidan; Fowler, Hayley J et al

Poster (2009, March)

Detailed reference viewed: 8 (3 ULg)
Peer Reviewed
See detailThe interaction of nanoparticles for drug delivery with biomimetic model membranes
Frost, Rickard; Cerda, Bernadino; Grandfils, Christian ULg et al

Poster (2009, February 24)

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See detailLe BCS, une méthode simple à la source de conseils variés : ration, repro et santé
Laloux, Laurent; Bastin, Catherine ULg; Gillon, Alain ULg et al

Poster (2009, February 11)

Detailed reference viewed: 17 (6 ULg)
See detailOrigin and evolution of SR proteins in Eukaryotes
Califice, Sophie ULg; Baurain, Denis ULg; Hanikenne, Marc ULg et al

Poster (2009, February 05)

Detailed reference viewed: 28 (5 ULg)
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See detailImportance of pigtailed macaques (Macaca nemestrina leonina) in seed dispersal and impact on the ecological balance of the tropical rainforest at Khao Yai National Park, Thailand
Albert, Aurélie ULg; Huynen, Marie-Claude ULg

Poster (2009, February)

The tropical rain forest is maintained thanks to a precarious balance placed under the yoke of interactions between the various animal and plant species which compose it. Among them we can find those ... [more ▼]

The tropical rain forest is maintained thanks to a precarious balance placed under the yoke of interactions between the various animal and plant species which compose it. Among them we can find those implying plants and frugivores. Although its diet is largely frugivorous, the pigtailed macaques (Macaca nemestrina leonina) have often been categorized as seed predators. However their morphology, behaviour and ecology suggest they could actually be a key-species in the dispersion of many plant species. A preliminary study by Latinne & al (2007) supported this hypothesis. The study we are planning now in continuity of Latinne’s study will take place in the Khao Yai National Park, Thailand, for three years and will focus on a troop habituated to humans. In order to establish the importance of the pigtailed macaques in the maintenance and the regeneration of the tropical rain forest, we will try to evaluate their capacity of being good seed dispersers. To do so, we will study: 1) the spatiotemporal distribution, the productivity and the characteristics of the plant species present on the home range of the studied troop, 2) the ranging patterns of the macaques within their home range, 3) their feeding behaviour, notably the fruit selection and the various modes of processing seeds, and finally 4) their impact on the viability and the germination potential of seeds. This study will require both direct observations of the macaques and semi-experimental procedures in the field, as well as laboratory control of some seed parameters. We hope the clarification of the macaques’ seed dispersal behaviour would help to re-evaluate their conservation status by recognizing them a paramount role in the maintenance of the tropical rainforest. [less ▲]

Detailed reference viewed: 19 (0 ULg)
Peer Reviewed
See detailEpidemiological study on European cases of atypical myopathy
Van Galen, Gaby ULg; Votion, Dominique ULg; Atypical Myopathy Alert Group

Poster (2009, January 28)

Detailed reference viewed: 102 (14 ULg)
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Peer Reviewed
See detailGreenland ice sheet surface mass balance projections from IPCC AR4 global models
Franco, Bruno ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg

Poster (2009, January 28)

Results from atmosphere-ocean general circulation models (AOGCM's) for the IPCC 4th Assessment Report are used to investigate surface mass balance (SMB) future projections of the Greenland ice sheet (GrIS ... [more ▼]

Results from atmosphere-ocean general circulation models (AOGCM's) for the IPCC 4th Assessment Report are used to investigate surface mass balance (SMB) future projections of the Greenland ice sheet (GrIS). The most efficient models for the GrIS climate modeling are chosen by comparison between the 1970-1999 outputs (averages and trends) from the Climate of the twentieth Century Experiment (20C3M) and reanalyses (ECMWF, NCEP) as well as observations (ice core measurements). The outputs from these most efficient models are after used to assess changes planned by the IPCC greenhouse gas emissions scenarios (SRES) for the 2070-2099 period. The GrIS SMB projections are estimated from changes in precipitation and temperatures from these AOGCM's outputs. However, large uncertainties remain in these SMB projections based on simplified physics and huge model outputs. High resolution simulations made with regional models (which simulate explicitly the SMB by taking into account the surface feedbacks) forced at their boundaries by a GrIS well-adapted AOGCM could bring more precise brief replies. [less ▲]

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See detailUse of C & N stable isotopes to evaluate interspecific trophic diversity among amphipods from Posidonia oceanica meadows
Michel, Loïc ULg; Lepoint, Gilles ULg; Nyssen, Fabienne ULg et al

Poster (2009, January 27)

Amphipods are one of the most diverse and abundant taxa of vagile invertebrates associated to Mediterranean Posidonia oceanica meadows. Therefore, they likely play an essential part in those ecosystems’ ... [more ▼]

Amphipods are one of the most diverse and abundant taxa of vagile invertebrates associated to Mediterranean Posidonia oceanica meadows. Therefore, they likely play an essential part in those ecosystems’ functioning, notably in organic matter transfers from producers to higher level consumers. Nevertheless, their trophic ecology remains poorly known, and they are generally regarded as epiflora grazers or generalist detritivores. Here, we focused on interspecific trophic diversity, and on the importance of other food sources (epifauna, Posidonia leaves & litter, suspended organic matter, …) in those amphipod’s diet. To achieve these goals, we used C and N stable isotopes ratios as trophic tracers. We noticed considerable trophic diversity among amphipods from different species, with δ13C values ranging from -16 to -26 ‰. Moreover, while some species (such as Apherusa chiereghinii and Aora spinicornis) seem to feed mainly on epiphytes, others, like Dexamine spiniventris, exploit other food sources. This study enhances the comprehension of the feeding ecology of these amphipods, and therefore of the way they interact with the Posidonia meadow ecosystem. [less ▲]

Detailed reference viewed: 84 (30 ULg)
See detailGround-based CO observations at the Jungfraujoch from 1997 till 2007: Comparison between FTIR and NDIR measurements
Dils, Bart; Demoulin, Philippe ULg; Mahieu, Emmanuel ULg et al

Poster (2009, January 26)

Here we will discuss CO measurements taken at the Swiss Alpine Jungfraujoch station (46.5º N, 8.0° E, 3580m a.s.l.) over the 1997-2007 time period. Results from two distinct techniques, namely Fourier ... [more ▼]

Here we will discuss CO measurements taken at the Swiss Alpine Jungfraujoch station (46.5º N, 8.0° E, 3580m a.s.l.) over the 1997-2007 time period. Results from two distinct techniques, namely Fourier Transform Infrared solar absorption spectrometry (FTIR), and the in situ Nondispersive Infrared technique (NDIR) have been compared. While the in situ NDIR measurements detect local CO concentrations at the site, the FTIR technique provides integrated measurements along the line-of-sight. Nevertheless, the pressure broadening of the spectral absorption lines recorded at high resolution enables retrieving information on the vertical distribution of CO, mainly in the troposphere, including its concentration near the surface. To provide enough information content the averaged vmr between 3.58 and 7 km is derived from the FTIR profile data. Both datasets show a significant negative trend over the time period. However, the NDIR dataset's negative trend is much stronger. Pettitt change point tests reveal that the NDIR-FTIR bias changes substantially from 1997 till 2004 after which the bias stabilizes. Possible causes for these observations will be critically discussed. [less ▲]

Detailed reference viewed: 53 (1 ULg)
See detailStoichiometry of bacteria and algae in Lake Kivu
Homblette, Nathalie; Darchambeau, François ULg; Heldal, Mikal et al

Poster (2009, January 25)

Detailed reference viewed: 12 (0 ULg)
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See detailDynamics of polysaccharides and transparent exopolymer particles during a coccolithophorid bloom in the Bay of Biscay
Händel, Nicole; Piontek, Judith; Harlay, Jérôme ULg et al

Poster (2009, January 25)

Carbohydrates comprise a large fraction (~30 %) of organic matter in the ocean (Pakulski and Benner, 1994). The production of polysaccarides (CCHO) in seawater is mainly linked to autotrophic processes ... [more ▼]

Carbohydrates comprise a large fraction (~30 %) of organic matter in the ocean (Pakulski and Benner, 1994). The production of polysaccarides (CCHO) in seawater is mainly linked to autotrophic processes. CCHO serve as structural and storage compounds, or are released by exudation, cell lysis or leakage to the dissolved organic matter pool. Concentrations of total hydrolyzable neutral sugars range from 200-800nM and 20-170nM in surface and deep waters, respectively (Benner, 2002). It has been shown that CCHO, in particular acidic polysaccharides, are involved in aggregation processes, e.g. the formation of transparent exopolymer particles (TEP). Recently, it has been suggested that ocean acidification increases TEP production, and therefore potentially enhances particle aggregation (Engel 2002, Mari 2008). Here, we present data on the abundance and composition of neutral and acidic CCHO and on TEP, obtained from field investigations and from CO2-controlled chemostat experiments that were conducted during a coccolithophore bloom in the Bay of Biscay 2006. Based on our findings, we discuss the partitioning of CCHO into gel particles, potential effects of ocean acidification and related consequences for organic matter export. [less ▲]

Detailed reference viewed: 35 (1 ULg)
See detailNutrient limitation of algae and bacteria in Lake Kivu (East Africa)
Darchambeau, François ULg; Leporcq, Bruno; Homblette, Nathalie et al

Poster (2009, January 25)

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See detailTowards a comprehensive C-budgeting approach of a coccolithophorid bloom in the Northern Bay of Biscay (June 2006)
Harlay, Jérôme ULg; Borges, Alberto ULg; De Bodt, Caroline et al

Poster (2009, January 25)

A biogeochemical multidisciplinary survey was carried out in the northern Bay of Biscay, in early June 2006, during which 14C-based primary production and calcification were determined as well as O2-based ... [more ▼]

A biogeochemical multidisciplinary survey was carried out in the northern Bay of Biscay, in early June 2006, during which 14C-based primary production and calcification were determined as well as O2-based community respiration. Contemporary remote sensing images showed several patches of high reflectance (HR) in the investigated area. Based on remote sensing and in situ measured biogeochemical parameters, the area exhibited varying coccolithophorid bloom stages from its early development to the post-bloom stages. The major HR patch, characterizing a post-stationary stage of the bloom, was located between 48°N and 49°N over the shelf along the continental margin. It was associated with moderate chlorophyll-a levels, never exceeding 1.0 µg L-1, dissolved phosphorus and silica depletion, and undersaturation of CO2 with respect to atmospheric equilibrium. Considered as the main drivers of the C cycle in this area, the CO2 fluxes associated with primary production, calcification and respiration were integrated in order to provide a comprehensive C budget in the area. [less ▲]

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See detailCell lysis during coccolithophorid blooms in the Northern Bay of Biscay
De Bodt, Caroline; Harlay, Jérôme ULg; Roevros, Nathalie et al

Poster (2009, January 25)

Phytoplankton cell lysis occurs in natural populations and is often associated with viral activity and zooplankton grazing. Cell lysis rates are expected to increase towards the decaying phase of the ... [more ▼]

Phytoplankton cell lysis occurs in natural populations and is often associated with viral activity and zooplankton grazing. Cell lysis rates are expected to increase towards the decaying phase of the bloom and may be associated with enhanced microbial activity and export of particulate matter to the seafloor. Their estimation was based on the measurement of esterase (a cytoplasmic enzyme) activity expected to appear in the water only after cell breakage. Field investigations, supported by remote sensing data, were conducted in recent years during late spring in the Northern Bay of Biscay, where frequent and recurrent coccolithophorid blooms are observed. Results on cell lysis rates determined in surface waters will be presented with relevant biogeochemical parameters (temperature, particulate organic and inorganic carbon, transparent exopolymer particles, nutrients, chlorophyll a) in order to investigate phytoplankton dynamics in relation to coccolithophorid development. The use of this parameter to characterize bloom termination, especially during coccolithophorid blooms will be discussed. [less ▲]

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See detailSynthesis of an universal linker to label oligonucleotides via Click Chemistry
Flagothier, Jessica ULg; Mercier, Frederic; Kaisin, Geoffroy ULg et al

Poster (2009, January 21)

For more than 3 decades, oligonucleotides have been used for therapies, imaging and diagnostics. They are known to hybridize specifically with RNA of a complementary sequence on tissue sections and more ... [more ▼]

For more than 3 decades, oligonucleotides have been used for therapies, imaging and diagnostics. They are known to hybridize specifically with RNA of a complementary sequence on tissue sections and more recently to block the expression of target mRNA when administered in vivo (1). Positron emission Tomography (PET) is a sensitive and non invasive imaging technique, and is the most advanced technology currently available for studying in vivo molecular interactions and therapeutic agents. It is a method of choice to assess the pharmacokinetics of new therapeutics agents such as modified oligonucleotides. Among positron-emitting nuclides, fluorine-18 (t1/2 = 109.8 min) appears to be the best candidate due to its favourable physical and nuclear properties. Several of the methods described in the literature to label oligonucleotides present a number of disadvantages (time of synthesis, low overall radiolabelling yield, non-universal). Due to the speed, selectiveness and the relatively mild experimentals conditions, “Click” chemistry seems a powerful technique. The most explored Click reaction is Huisgen 1,3 dipolar cycloaddition. In our case, this reaction occurs between an alkyne group presents on the oligonucleotide and an azide group on the 18F labelled prosthetic group. The originality of our strategy is the use of a universal linker diverted from the trans-4-hydroxy-proline directly connected to the oligonucleotide. This linker mimics a sugar of the oligonucleotide sequence and should improve their resistance to exonucleases. Synthesis of this compound will be presented. [less ▲]

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See detailNouvelles relations entre scientifiques et communautés locales dans la gestion des aires protégées
Escobar Jimenez, Kelly ULg

Poster (2009, January 09)

L'exploration de nouvelles relations entre communautés locales et milieux scientifique se concentre sur: un processus: la prise de décisions sur les limites, les espèces et les communautés responsables ou ... [more ▼]

L'exploration de nouvelles relations entre communautés locales et milieux scientifique se concentre sur: un processus: la prise de décisions sur les limites, les espèces et les communautés responsables ou “bénéficiaires” des aires protégées en Amazonie Équatorienne; sur une autorité: les concepts techniques et scientifiques sur les caractéristiques et la gestion des aires protégées en AL, notamment en Amazonie Équatorienne; et sur des relations: la gestion des aires protégées constitue-t-elle un scénario de nouvelles relations entre scientifiques et communautés locales, vu les démarches participatives généralisées en Amérique latine ? [less ▲]

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Peer Reviewed
See detailRecent threats on coastal ecosystems by new pollutants: a multiple trace element study
Richir, Jonathan ULg; Gobert, Sylvie ULg; Bouquegneau, Jean-Marie ULg

Poster (2009, January)

The Mediterranean Sea is an enclosed basin, highly submitted to anthropogenic pressures. Chemical pollution from coastal urban centres and industries, or carried by air and rivers, primarily affects its ... [more ▼]

The Mediterranean Sea is an enclosed basin, highly submitted to anthropogenic pressures. Chemical pollution from coastal urban centres and industries, or carried by air and rivers, primarily affects its coastal ecosystems. Pollution by trace elements is rapidly evolving further to the recent modifications of their production and industrial uses by men. As a result, certain trace elements can now be considered as new environmental pollutants. Appropriate bioindicators are useful tools for the early warning of marine pollution. We presently investigate the use of the purple sea urchin Paracentrotus lividus and the marine phanerogam Posidonia oceanica as bioindicators to monitor the Mediterranean coastal pollution by new trace pollutants (Be, V, Mo, Mn, PGEs, Ag, Al, As, Se, Sb and Bi). Classic trace metals (Cd, Cr, Cu, Zn, Ni, Sn, Pb, Co and Fe) are also studied. Organisms were seasonally collected in 2008 in a reference site and a polluted one, respectively Calvi bay (Corsica) and Marseille (France). Their tissular trace element concentrations were determined by ICP-MS. All the investigated trace elements were chosen for their potential toxic effects. [less ▲]

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Peer Reviewed
See detailLes habitudes de sommeil chez les enfants de 2,5 à 6 ans
Philippe, Paule ULg; Scholl, Jean-Marc ULg; Zdanowicz, Nicolas

Poster (2009, January)

Introduction: les habitudes de sommeil chez les enfants sont éminemment variables suivant les enfants, les âges, les habitudes ou contraintes familiales. Elles sont d’autre part peu connues et peu ... [more ▼]

Introduction: les habitudes de sommeil chez les enfants sont éminemment variables suivant les enfants, les âges, les habitudes ou contraintes familiales. Elles sont d’autre part peu connues et peu investiguées en consultation. Mais peut-on relever des différences entre une population générale "normale" et une population prise en charge dans des consultations psychologiques ambulatoires? Méthode: un questionnaire concernant les habitudes de sommeil a été distribué à des parents d’enfants fréquentant l’enseignement ordinaire et à des parents d’enfants fréquentant des consultations psychologiques ambulatoires. 496 réponses (356 pour la population générale et 140 pour les enfants suivis en consultation) ont été recueillies et analysées. Des différences de distributions ont été mises en évidence entre les 2 groupes et des corrélations recherchées. Paramètres recherchés : - le nombre d’heures de sommeil par nuit en semaine et le week-end ; - le nombre d’enfants « couche-tôt » ou « couche-tard » ; - les caractéristiques de l’endormissement: l’enfant retarde la mise au lit, il a besoin d’une sucette/ d’un doudou/ d’un morceau de tissu/ d’un biberon/ de lumière ou noir complet/ d’une TV/ que la porte soit ouverte/ il manifeste un inconfort/ des peurs/ il s’endort seul dans sa chambre ou en présence d’un adulte avec éventuellement le besoin de tenir physiquement cet adulte/ durée moyenne de l’endormissement - l’endroit où dort l’enfant : dans sa chambre, avec un frère/ une sœur, dans la chambre des parents, dans une pièce de séjour commune … - les caractéristiques du temps de sommeil : sommeil agité, réveils nocturnes, cauchemars, cherche à rejoindre ses parents pendant la nuit Conclusions: les comportements liés au sommeil différencient spécifiquement le groupe des enfants recrutés dans les Services de Santé Mentale par rapport au groupe témoin. Dans notre pratique, une anamnèse détaillée dans ce domaine permet d’attirer l’attention sur une population fragile, à examiner plus attentivement et éventuellement à prendre en charge dès que possible. Une information et une aide pour les parents est à envisager très précocement; une information serait utile également pour les différents professionnels (puéricultrices, enseignants, éducateurs, médecins traitants...). [less ▲]

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See detailWeekly satellite sea surface temperature around Corsica, a DINEOF analysis of AVHRR data (1998), foreseeing comparison with interpolated and modelled fields.
Sirjacobs, Damien ULg; Lenartz, Fabian ULg; Troupin, Charles ULg et al

Poster (2009, January)

Providing wide coverage and high spatio-temporal resolution, SST satellite archives are valuable sources of information for sound understanding of the ocean dynamics, including validation of ... [more ▼]

Providing wide coverage and high spatio-temporal resolution, SST satellite archives are valuable sources of information for sound understanding of the ocean dynamics, including validation of hydrodynamical modelling studies. Yet original SST fields have also many gaps (clouds, retrieval problems), but they are known to exhibit strong spatial and temporal correlations for regions of similar dynamics. This is exploited by the parameter free statistical technique DINEOF (Data Interpolation with Empirical Orthogonal Functions) [Alvera-Azcárate et al. (2005) Ocean Modell.; Beckers et al. (2006) Ocean Sciences] to produce full weekly analysis of the variability of the sea surface temperature (SST) around Corsica and in the Ligurian Sea at weekly temporal resolution during the year 1998. A detection of outliers implemented in DINEOF analysis is tested for pointing out unusual or invalid SST data. This study is realised foreseeing a comparison of DINEOF weekly averaged reconstructed fields with those obtained by interpolating methods on the same dataset (Data Interpolating Variationnal Analysis and Optimal Interpolation schemes), and with outputs of an implementation of the GHER 3D model in this area. [less ▲]

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See detailEvidence for wastewater influence in a low impacted area throughout stable isotope analyses of the limpet Patella caerulea and epilithic biofilms
Vermeulen, Simon ULg; Lepoint, Gilles ULg; Gobert, Sylvie ULg

Poster (2009, January)

Eutrophication is considered to be one of the main threats to marine environments leading to changes in trophic status of ecosystems and alteration of biological diversity. Carbon and Nitrogen stable ... [more ▼]

Eutrophication is considered to be one of the main threats to marine environments leading to changes in trophic status of ecosystems and alteration of biological diversity. Carbon and Nitrogen stable isotopes analyses were performed on the limpet Patella caerulea and one of its food sources (epilithic biofilms) to assess their potential as early indicators of eutrophication. Samples were seasonally collected in 2005-2006 on five locations gradually exposed to urban sewage in the Calvi Bay and in the Marseilles harbour. Stable isotope signatures of Patella caerulea muscles exhibited steady site - specific values over seasons. In contrast to this time – integrated signal, wide variations in biofilm values show that either composition or isotopic ratios of food sources may vary greatly in time and space. Elevated δ15N values of limpets and biofilms, typical of wastewater influence but unrelated to nitrogen loads, indicate the biological availability of sewage-derived nitrogen in the Calvi Bay and the Marseilles harbour. A reference level of δ15N values is rapidly reached with increasing depth that indicates the limited vertical extent of pollution in the Calvi Bay. [less ▲]

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See detailFish farm impacts on Posidonia oceanica meadows: interest of the microbenthic loop.
Pete, Dorothée ULg; Velimirov, Branko; Bouquegneau, Jean-Marie ULg et al

Poster (2009, January)

Posidonia oceanica, the seagrass endemic to the Mediterranean Sea, is a valuable tool to assess the environmental quality in coastal zones. However, only few studies have attempted to use characteristics ... [more ▼]

Posidonia oceanica, the seagrass endemic to the Mediterranean Sea, is a valuable tool to assess the environmental quality in coastal zones. However, only few studies have attempted to use characteristics of its sediment compartment as an indicator of environmental perturbations. In this study, the impact of a fish farm on the microbenthic loop (organic matter, bacteria, microphytobenthos and meiofauna) of P. oceanica meadows will be described. Samples were taken under an aquaculture situated in Calvi Bay (Corsica, France) at a depth of 22 m, in March and June 2008. The control site was the meadow situated in front of the research station STARESO (Calvi Bay, Corsica, France), sampled at the same periods and depth. Results concerning bacteria, microphytobenthos and organic matter will be presented here. For both seasons, differences between sites exist. For example, biomasses of organic matter, microphytobenthos and bacteria are higher in the fish farm than in the control site, indicating that the microbenthic loop has potential to be a good early indicator of pollution in this sea. [less ▲]

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See detailChemical and enzymatical modifications of sugar derived from lignocellulose
Richard, Gaetan ULg; Laurent, Pascal ULg; Nott, Katherine ULg et al

Poster (2009, January)

Actually, biorefinery is increasingly considered as a promising alternative to petroleum chemistry, since it aims at not only the replacement of fossil energy but also the development of chemicals from ... [more ▼]

Actually, biorefinery is increasingly considered as a promising alternative to petroleum chemistry, since it aims at not only the replacement of fossil energy but also the development of chemicals from biomass, with applications such as detergents, phytopharmaceutics, solvents, plastics, etc. The valorisation of carbohydrates from renewable raw materials is currently the subject of numerous researches. In this context, the synthesis of new surfactants derived from the sugars issued from the lignocellulose hydrolysis was undertaken by chemical or enzymatic routes. In this poster, the examples of glucose, cellobiose and uronic acids will be discussed. Whatever the way used, the reaction conditions (use of a catalyst, protection/deprotection steps, type of solvent, presence of co-solvent, reactant concentrations, etc) were optimized to yield a panel of carbohydrate derivatives (some examples of the structures obtained are given above). These differ by the nature of the alkyl chain (in length and in degree of saturation), the type of chemical bond (amide, ester, thioester, acetal), and the position of substitution. The impact of these differences on the techno-functional properties of these modified sugars will be evaluated. [less ▲]

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See detailFluctuation of sediment production during the last millennia in the Ardenne Massif (Belgium)
Houbrechts, Geoffrey ULg; Notebaert, Bastiaan; Petit, François ULg et al

Poster (2009)

In the Ardenne massif, floodplains have recorded fluctuations in the production of sediment and several periods of increased sediment deposition have been identified. Before the first deforestations ... [more ▼]

In the Ardenne massif, floodplains have recorded fluctuations in the production of sediment and several periods of increased sediment deposition have been identified. Before the first deforestations rivers developed multiple channels in alluvial forests. Floodplains were not well-developed and probably very humid, which explains the presence of peat layers within the alluvial sequences. In the Amblève catchment, the first increased sedimentary deposition of the Holocene occurred during the Bronze Age (3200 BP), in relation to deforestation and the first crop cultures in the area. An organic deposition has occurred around 2700 BP and could correspond with a period of climatic degradation. Several peat layers have also been dated to around 1000 BP and probably indicate very low anthropogenic pressure. From the 11th Century onwards, there was an increase in sedimentation and a greater concentration of charcoal is present in the alluvial deposits. In many catchments there is an important increase in the sedimentation at the end of the 14th century, which can be related to the development of many iron factories. Analyses of slag concentration produced in these former factories allow us to reconstruct the evolution of the floodplain topography since the inception of the iron industries, in relation to the periods of activity. Total sedimentation in the smaller valleys since the initiation of iron industries amounts 0.5 to 1.0 m, which is in most cases about 50% of the total sediment present in the floodplains and corresponds to a mean sedimentation rate ranging between 10 and 20 cm/century. Such values are explained by various former agricultural practices and forest clearings associated with the huge demand for charcoal by the iron industry. About 20 ha of forest were cleared for the yearly consumption of a refining forge or a blast furnace and more than three hundred iron factories existed in the Ardenne Massif between the 14th and the 19th century. [less ▲]

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