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See detailDevelopment of a financial model for Geriatric Day Hospitals
Gillain, Daniel ULg; Fecher-Bourgeois, Fabienne ULg; Velghe, A. et al

Poster (2009)

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See detailThe post-harvest quality of bananas is determined by pre-harvest factors
de Lapeyre de Bellaire, Luc; Chillet, Marc; Lassois, Ludivine ULg et al

Poster (2009)

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See detailHolocene environmental changes in lake sediments from Northern Chilean Patagonia (45-48°S)
Nuttin, L.; Fagel, Nathalie ULg; Bertrand, S. et al

Poster (2009)

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See detailDéveloppement des filières Jatropha décentralisées au Sénégal
Terren, Marieke ULg; Saverys, S.; Jacquet de Haverskercke, P et al

Poster (2009)

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See detailNutritional markers course after oral supplementation with different forms of iodine in Holstein non-lactating cows
Guyot, Hugues ULg; VanParijs, Sandrine; Uyttenhoef, Aude et al

Poster (2009)

Iodine (I) deficiency is commonly reported in cattle around the world and is often associated with clinical or sub-clinical diseases. As most of clinical signs are not pathognomonic, diagnosis has to be ... [more ▼]

Iodine (I) deficiency is commonly reported in cattle around the world and is often associated with clinical or sub-clinical diseases. As most of clinical signs are not pathognomonic, diagnosis has to be confirmed by biochemical analyses such as plasmatic inorganic iodine (PII) or urinary I. Different oral mineral forms of I are available in Europe for cattle. The aim of the study was to compare the kinetic of I in blood and urine in non-lactating cows, following oral administration of different forms of I. Five groups of 6 non-lactating cows (aged 6 ± 2 years, weight 604 ± 89 kg), receiving the same ration (11 kg dry matter) and housed in the same conditions (tied-stall and straw) underwent a double-blinded trial during 2 months. Excepting in Group A (Control), all cows received a daily oral supplementation of I equal to 5 ppm, in the form of Ca(IO3)2 (Group B), KI (Group C), organic form of I 1 (Group D) and organic form of I 2 (Group E). Formulas of the organic forms of I are not public and coverable by patent. Supplementation was stopped at T45. Blood and urine samples were taken at T0, T15, T30 and T60. Thyroxine (T4) was measured at T0, T30 and T60 while PII and urinary I were measured at the 4 times of the trial. Student-t test and multiple comparisons of means (mix crossed model) were used to compare I and T4 concentrations between groups and times. All characteristics about the cows and I levels in blood or urine were not significantly different at T0 (p>0.1). There was no significant difference (p>0.1) between groups B, C, D, E at the different times of the trial. PII and urinary I in Group A were significantly lower than in other groups (p<0.01) at T15 and T30. Highest concentrations of I (PII up to 242 ± 30 µg/L and urinary I up to 2326 ± 439 µg/L) were reached at T15 for groups B, D and E. At T60, PII (19 ± 4 µg/L) and urinary I (110 ± 29 µg/L) of all groups reached the basal level. A good correlation was found between PII and urinary I (r² = 0.77). No significant differences were found about T4 (67 ± 10 nmol/L) in all groups and times (p>0.1). PII and urinary I are good markers to assess I nutritional status. No difference was found between either inorganic or organic forms of I, nor between them. Concerning the mineral forms of I, Ca(IO3)2 might be preferably used because of its higher stability in the mineral complexes. [less ▲]

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See detail3D anatomy of Heinrich Layer 2.
Van Rooij, D.; Zaazi, N.; Fagel, Nathalie ULg et al

Poster (2009)

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See detailENVIRONMENTAL ASPECTS OF CLAY EXPLOITATION FOR FIRED CLAY BRICKS IN CAMEROON
Njoya, A.; Bastin, D.; Melo, U. et al

Poster (2009)

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See detailMCF-7/BOS cells membrane proteome: comparison of two isolation methods using mass spectrometry
Bertrand, Virginie ULg; Massart, Anne-Cécile ULg; De Pauw-Gillet, Marie-Claire ULg et al

Poster (2009)

Membrane proteins play an important role in biological processes but their isolation and quantification using classical techniques is often limited due to their poor solubility and relatively low ... [more ▼]

Membrane proteins play an important role in biological processes but their isolation and quantification using classical techniques is often limited due to their poor solubility and relatively low abundance. These membrane markers have to be accessible to antibodies and should be potential therapeutic targets. The tests were conducted on MCF-7 / BOS cell line, immortal and easier to cultivate. The goal of this work is to obtain a pure membrane fraction to facilitate the analysis of the sample. To isolate transmembrane proteins, we compared two methods. The first one used different extraction cycles characterized by different buffers to isolate membrane proteins. The second method labelled accessible extracellular domains at the surface of MCF-7 cells with biotin prior to differential centrifugation. [less ▲]

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See detailOutreach goals of the Europa Jupiter System Mission
Blanc, M.; Coustenis; Nazé, Yaël ULg et al

Poster (2009)

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See detailPercutaneous penetration studies of ibuprofenencapsulated into nanoparticles using different skin membrane models
Destrée, Caroline; Wouters, Johan; Deleu, Magali ULg et al

Poster (2009)

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See detailCHARACTERIZATION AND OPTIMIZATION OF PEPTIDE ENCAPSULATION IN PEGYLATED LIPOSOMES
Ducat, Emilie ULg; Brion, Michael; Evrard, Brigitte ULg et al

Poster (2009)

Purpose: Print 3G is a peptidic antagonist of oncoprotein involved in breast cancer, containing 25 amino acids. The purpose of this work is to study the peptide encapsulation into PEGylated liposomes. Two ... [more ▼]

Purpose: Print 3G is a peptidic antagonist of oncoprotein involved in breast cancer, containing 25 amino acids. The purpose of this work is to study the peptide encapsulation into PEGylated liposomes. Two formulations composed of SPC:CHOL:mPEG-750-DSPE (47:47:6) or SPC:CHOL:mPEG-2000-DSPE (47:47:6) were investigated. Methods: Unilamellar vesicles containing either mPEG750 or mPEG2000 were prepared by hydration of lipid films method. Unfortunately, a loss of Print 3G was observed during the different steps of this manufacturing technique giving rise to encapsulation efficiencies close to 0 %. Thus, the freeze-thawing method was used to enhance the amount of Print 3G encapsulated into blank liposomes prepared using the above procedure. Because many factors may influence the peptide entrapment into the vesicles (number of freeze-thawing cycles, lipid concentration, peptide concentration, mixing time and liposome composition), a design of experiment was performed (for the screening, a Plackett and Burman plan; for the optimization, a central composite design). Results: The encapsulation efficiencies obtained by the freeze-thawing method in standard conditions, varied between 17.26 ± 0.46 % (n=3) for liposomes containing mPEG750 and 26.20 ± 7.98 % (n=3) for those comprising mPEG2000. Among the different considered factors, the screening permitted to identify two factors having a positive and significant influence on the encapsulation efficiencies: the number of freeze-thawing cycles and the lipid concentration, while the presence of mPEG2000 or mPEG750 had a relatively weak effect on the encapsulation. Concerning the peptide concentration and the mixing time, no influence was revealed. For the second part of the DOE, the positive factors were optimized for the liposomes containing mPEG2000. The obtained results for liposomes containing mPEG2000 revealed a theoretical optimum at 64.75 ± 3.55 % when 11 freeze-thawing cycles were applied and for the following lipid concentrations: 36.1 mM SPC, 36.1 mM CHOL and 4mM mPEG-2000-DSPE. The experimental results showed an encapsulation efficiency of 62.68 ± 2.93 %. Conclusion: Changing the manufacturing technique permitted a significant encapsulation of Print 3G into liposomes. The DOE led to a significant improvement of encapsulation efficiencies for the liposomes containing mPEG2000. Thereafter, an optimization design for liposomes containing mPEG750 will be started. Acknowledgements: This work was supported by the Ministry of the Walloon Region. [less ▲]

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See detailCHARACTERIZATION AND OPTIMIZATION OF PEPTIDE ENCAPSULATION IN PEGYLATED LIPOSOMES
Ducat, Emilie ULg; Brion, Michael; Evrard, Brigitte ULg et al

Poster (2009)

Purpose: The purpose of this work is to study the peptide encapsulation into PEGylated liposomes. Two formulations (SPC:CHOL:mPEG-750-DSPE (47:47:6) or SPC:CHOL:mPEG-2000-DSPE (47:47:6)) were investigated ... [more ▼]

Purpose: The purpose of this work is to study the peptide encapsulation into PEGylated liposomes. Two formulations (SPC:CHOL:mPEG-750-DSPE (47:47:6) or SPC:CHOL:mPEG-2000-DSPE (47:47:6)) were investigated. Methods: Blank SUV liposomes were prepared by the lipid film hydration and the encapsulation was achieved by applying freeze-thawing cycles. Because many factors may influence peptide entrapment (number of freeze-thawing cycles (NC), lipid concentration (LC), peptide concentration (PC), mixing time (MT) and liposome composition (COMP)), a design of experiment (DOE) was performed. Results: The screening permitted to identify two factors having a positive and significant influence on the encapsulation efficiencies (NC and LC) while the liposome composition had a relatively weak effect. For the second part of the DOE, the positive factors were optimized for liposomes containing mPEG2000. The obtained results revealed a theoretical optimum at 64.75±3.55% when 11 cycles were applied and for the following LC: 36.1mM SPC, 36.1mM CHOL and 4mM mPEG-2000-DSPE. Experimental results showed an encapsulation efficiency of 62.68±2.93%. Conclusion: The DOE led to significant improvement of encapsulation for liposomes containing mPEG2000. Thereafter, an optimization design for liposomes containing mPEG750 will be started. Acknowledgements: This work was supported by the Ministry of the Walloon Region. [less ▲]

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See detailEvaluation of the contamination of North Sea Porpoises (Phocoena phocoena) by endocrine disrupting chemicals using CG-MS and in vitro assays
Didimo Imazaki, Pedro Henrique ULg; Brose, François ULg; Remacle, Anne-Sophie ULg et al

Poster (2009)

During the last decades, the production of endocrine disrupting chemicals reached such elevated levels that they are now spread all over the environment. Endocrine disrupting chemicals are known to be ... [more ▼]

During the last decades, the production of endocrine disrupting chemicals reached such elevated levels that they are now spread all over the environment. Endocrine disrupting chemicals are known to be very slowly degraded, decreasing the environmental quality and causing ecological risks. Marine mammals inhabiting polluted environments accumulate high quantities of these chemicals, and are good indicators of marine pollution Thirteen major organochloride pollutants (known from literature to contaminate north sea porpoise) were chosen in this study – o,p’-DDD; p,p’-DDD; p,p’-DDE; o,p’-DDT; p,p’-DDT; HCB; α-HCH; β-HCH; γ-HCH; δ-HCH; PCB 138; PCB 153 and PCB 180. The thirteen chemicals were tested individually and in mixtures by the use of report gene expression assays. The MCF7-ERE cells used in the assays were originated from MCF7 human mammary tumor cells transfected with the ERE-luciferase reporter system. Preliminary results suggest that o,p’-DDD; p,p’-DDD; o,p’-DDT; HCB; β-HCH; δ-HCH; PCB 138 and PCB 180 are able to stimulate the luciferase expression of MCF7-ERE cells when they are present individually or in mixtures. No synergism was observed within mixtures. When MCF7-ERE cells were exposed to the chemicals and 17β-oestradiol simultaneously, p,p’-DDE; α-HCH; PCB 138 and PCB 180 could raise the luciferase expression in comparison to the exposition of 17β-oestradiol alone; on the other hand, o,p’-DDD; p,p’-DDT; HCB; β-HCH; γ-HCH and δ-HCH seem to inhibit the luciferase expression at low doses. In the next step, the pollutants will be searched and quantified in the blubber tissue of porpoises by use of gas chromatography-mass spectrometry. The blubber tissue samples will also have their endocrine disrupting effects characterized. This work is ongoing and It is expected a relevant level of these compounds to be found in the samples. Conversely, their endocrine disrupting effects and how they act in agonist, antagonist ways are subject that still needs to be studied. [less ▲]

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See detailImpact de l’action anthropique sur la diversité floristique et structurale de la forêt de Rumonge au Burundi
Hakizimana, P; Lejoly, J; Habonimana, B et al

Poster (2009)

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See detailHolocene environmental changes in lake sediments from Northern Chilean Patagonia
Nuttin; Fagel, Nathalie ULg; Brogniet et al

Poster (2009)

Detailed reference viewed: 33 (0 ULg)
See detailevaluation of two protein extractions protocols for pichia anomala proteome analysis
Bajji, M.; Delaplace, Pierre ULg; Mauro, S. et al

Poster (2009)

Detailed reference viewed: 29 (6 ULg)
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See detailCoupled hydro-thermo-mechanical analysis of a deep radioactive waste disposal based on porous media mechanics
Passarotto, Mareva; Luison, Loris; Sanavia, Lorenzo et al

Poster (2009)

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See detailPurification de protéines associées à la gestation (PAG) chez le porc
Dethier, M.; Melo de Sousa, Noelita ULg; Balci, S. et al

Poster (2009)

Detailed reference viewed: 19 (2 ULg)
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See detailDepth resolution and surface transients in crystalline Silicon at ultra low energies
Goossens, Jozefien; Berghmans, Bart; Franquet, Alexis et al

Poster (2009)

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See detailInvolvement of autophagic pathway in the hypoxia-induced resistance to etoposide in HepG2
Cosse, Jean-Philippe ULg; Sermeus, Audrey; Flamant, Lionel et al

Poster (2009)

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See detailFunctional amphiphilic and degradable copolymers for drug delivery systems
Freichels, Hélène ULg; Pourcelle, Vincent; Plapied, Laurence et al

Poster (2008, December 18)

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See detailBiohydrogen production from anaerobic digestion of carbohydrate organic matter.
Hiligsmann, Serge ULg; Masset, Julien ULg; Beckers, Laurent ULg et al

Poster (2008, December 16)

Hydrogen has received wide attention in the last decade as a clean energy vector. The major advantage of energy from hydrogen is the zero carbon emissions, since the utilization of hydrogen, either via ... [more ▼]

Hydrogen has received wide attention in the last decade as a clean energy vector. The major advantage of energy from hydrogen is the zero carbon emissions, since the utilization of hydrogen, either via combustion or via fuel cells, results in pure water. At industrial scale, steam reformation of methane is currently the major hydrogen producing process. However recently, increasing interest has been paid on biological production of hydrogen gas. Indeed, biohydrogen generation from renewable biomass would reduce dependence on fossil fuel, decrease the carbon dioxide emissions and produce usable bioenergy. Biological production of hydrogen using anaerobic bacteria is an exciting and promising new area of technology development that offers the potential production of usable hydrogen from a variety of renewable resources such as carbohydrates from agriculture or agro-food industries. This biological system is called dark fermentation and the most interesting bacteria strains are Clostridium sp. The investigations carried out at CWBI involve selection and characterization of bacteria strains, optimization of the biotechnological process and design of highly efficient bioreactors. [less ▲]

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See detailLes mobilisations pour la cause des femmes en RDCongo
Grenade, Sophie ULg

Poster (2008, December 12)

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See detailCharacteristics of Saturn's polar atmosphere and auroral electrons derived from HST/STIS, FUSE and Cassini/UVIS spectra
Gustin, Jacques ULg; Pryor, W.; Feldman, P. et al

Poster (2008, December 01)

Ultraviolet spectra of Saturn's aurora obtained with the Hubble Space Telescope Imaging Spectrograph (STIS), the Cassini Ultraviolet Imaging Spectrograph (UVIS) and the Far Ultraviolet Spectroscopic ... [more ▼]

Ultraviolet spectra of Saturn's aurora obtained with the Hubble Space Telescope Imaging Spectrograph (STIS), the Cassini Ultraviolet Imaging Spectrograph (UVIS) and the Far Ultraviolet Spectroscopic Explorer (FUSE) have been compared to synthetic spectra of electron-excited H2 in order to derive various auroral characteristics, such as the energy of the primary precipitating electrons and the H2 temperature at the altitude of the aurora. Two physical processes have been exploited: the absorption by hydrocarbons in the FUV and H2 self-absorption in the EUV. We find energies in the range 10-18 keV, which locates Saturns's aurora between 0.1 and 0.3 μ bar. We also determined that the auroral H2 emission is characterized by a temperature of ~400K, consistent with temperatures measured in the infrared, but much higher than what is expected from equatorial atmospheric models. These new results bring valuable constraints on both polar atmospheric models and theoretical studies of the ionosphere-magnetosphere coupling. [less ▲]

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See detailOverlay Routing using Coordinate Systems
Cantin, François ULg; Gueye, Cheikh Ahmadou Bamba ULg; Kaafar, Mohamed Ali ULg et al

Poster (2008, December)

We address the problem of finding indirect overlay paths that reduce the latency between pairs of nodes in an overlay. To this end we propose to rely on an Internet Coordinate System (ICS), namely Vivaldi ... [more ▼]

We address the problem of finding indirect overlay paths that reduce the latency between pairs of nodes in an overlay. To this end we propose to rely on an Internet Coordinate System (ICS), namely Vivaldi, to estimate RTTs and help find these interesting detours. We define two initial criteria to illustrate our approach and assess their true/false positive rates. [less ▲]

Detailed reference viewed: 105 (48 ULg)
See detailSignes de conflit d’intentions dans un syndrome de déconnexion calleuse : cas J.B.
VINCENT, Eric ULg; DELRUE, Gaël ULg; SALMON, Eric ULg et al

Poster (2008, December)

Presentation of a patient showing multiple symptoms of a callosal disconnection.

Detailed reference viewed: 9 (2 ULg)
See detailCarbon Cycle and Climate Sensitivity in an Earth System Model
Mouchet, Anne ULg; Loutre, M.; Fichefet, T. et al

Poster (2008, December)

The sensitivity of the potential feedbacks between climate and biogeochemical cycles (BGC) is adressed with the help of LOVECLIM, a global three-dimensional Earth system model of intermediate complexity ... [more ▼]

The sensitivity of the potential feedbacks between climate and biogeochemical cycles (BGC) is adressed with the help of LOVECLIM, a global three-dimensional Earth system model of intermediate complexity. Key physical or biogeochemical parameters of LOVECLIM are varied within their range of uncertainty in order to provide an ensemble of parameter sets resulting in contrasted climate and global carbon cycle sensitivities. The selected climate parameter sets lead to a climate sensitivity ranging from 2 to 4°C and a reduction of the Atlantic meridional overturning circulation (MOC) ranging from 20 to 60% after 1 kyr in response to identical external forcings. The key parameters for the carbon cycle were chosen among those with the largest impact on the marine biogeochemical cycle and on the response of atmospheric CO2 to emission scenario. We then analyze the results of freshwater hosing experiments in which both the climate parameters and the BGC parameters are modified. These experiments allow to examine the impact of changes in climate sensitivity and of MOC reduction over the biogeochemical cycles as well as to assess the potential feedback from the carbon cycle onto the climate. A decreasing MOC directly impacts the ocean biogeochemistry. Most of the model setups show a decline in export production although some parameter sets yield reorganisation of the large scale ocean circulation, which leads to different behaviour of the ocean biogeochemistry. The atmospheric carbon is also affected by a decrease of the MOC. While most parameter sets cause a modest increase in atmospheric CO2, consecutive to the decrease of the continental vegetation, some model versions exhibit an amplification of the atmospheric CO2 response to the forcing. The mechanisms leading to the different responses for the different parameter sets are examined and discussed. [less ▲]

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See detailPreparation and characterization of thermoresponsive iron nanoparticles for biomedical applications
Sibret, Pierre ULg; Aqil, Abdelhafid ULg; Gohy, Jean-François et al

Poster (2008, November 28)

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See detailElectrografting of thermo-responsive polymer films on conducting surfaces
Gabriel, Sabine; Stach, M.; Confortini, O. et al

Poster (2008, November 28)

Detailed reference viewed: 27 (2 ULg)
See detailPolymer membrane by electrospinning
Aqil, Abdelhafid ULg; Grignard, Bruno ULg; Croisier, Florence ULg et al

Poster (2008, November 28)

Detailed reference viewed: 41 (9 ULg)
See detailNew strategies to prepare melt processable polymer-grafted gold nanoparticles
Alexandre, Michaël ULg; Abetz, Volker; Boschetti-de-Fierro, A. et al

Poster (2008, November 28)

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See detailLe Childhood Anxiety Sensitivity Index-Revised (CASI-R) : Etude de validation.
Stassart, Céline ULg; Depauw, Brigitte; Delvaux, Muriel ULg et al

Poster (2008, November 28)

La sensibilité à l'anxiété est la peur des sensations corporelles liées à l’anxiété, qui proviendrait de croyances que ces sensations ont des conséquences somatiques, psychologiques ou sociales néfastes ... [more ▼]

La sensibilité à l'anxiété est la peur des sensations corporelles liées à l’anxiété, qui proviendrait de croyances que ces sensations ont des conséquences somatiques, psychologiques ou sociales néfastes. Ce concept a été très peu exploré dans le contexte infantile. L’AS étant considérée comme un facteur de risque dans le développement et le maintien des troubles anxieux, ceci montre l’intérêt de s’intéresser davantage à l’outil d’évaluation de l’AS dans le contexte infantile, le Childhood Anxiety Sensitivity Index revised. L'objectif de cette étude est de d'évaluer les propriétés psychométriques de la version française de la CASI-R auprès d'un échantillon de 60 enfants âgés de 10 à 11 ans. En ce qui concerne les résultats, la confrontation de la CASI-R aux qualités psychométriques nous fournit des premiers éléments en faveur de l’intérêt clinique et de la pertinence théorique de cet outil dans le contexte infantile. En ce sens, la poursuite de son développement paraît constituer une perspective intéressante. [less ▲]

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See detailModelling the Ionosphere over Europe: Investigation of NeQuick Formulation
Bidaine, Benoît ULg; Warnant, René ULg

Poster (2008, November 18)

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones ... [more ▼]

The modelling of the Total Electron Content (TEC) plays an important role in global satellite navigation systems (GNSS) accuracy, especially for single-frequency receivers, the most common ones constituting the mass market. For the latter and in the framework of Galileo, the NeQuick model has been chosen for correcting the ionospheric error contribution. It has been designed to calculate the electron density at a given point of the ionosphere according to the time conditions and the solar activity. This electron density can be integrated along the path from the receiver to the considered satellite to provide the TEC. For Galileo, a parameter Az (“effective ionisation level”) will be provided to the model as solar activity information and will be daily updated by the ground stations. Since NeQuick was chosen for Galileo purpose, a new version of the model has been released. It involves simplifications in the representation of the bottomside as well as a unique formula for a key parameter of the topside formulation previously defined through two equations, each one used for six months of the year. Hence we decided to investigate consecutive improvements and remaining weaknesses of this new formulation. To this extent, we take benefit of various ionosphere data from several European stations (Chilton in UK, Dourbes in Belgium, El Arenosillo and Roquetes in Spain, Pruhonice in Czech Republic) where ionosonde and GPS TEC data are available for different solar activity levels. These data allow us to study NeQuick representation of the ionosphere at mid-latitudes. We investigate the difference between GPS-derived vTEC and corresponding values from NeQuick for the latest years (between solar maximum in 2000 and minimum in 2007) in order to observe the temporal dependencies towards Universal Time, season and solar activity. We use ionosonde data to constrain the model so that we can concentrate on its formulation of the profile only. We especially highlight the improvements from the second version of NeQuick and show the critical importance of the topside formulation. [less ▲]

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See detailIonospheric variability which degrades the precision of real time GNSS applications
Wautelet, Gilles ULg; Lejeune, Sandrine; Warnant, René ULg

Poster (2008, November 18)

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See detailDirect block of SK2 and SK3 current by the sigma agonist 1,3-di-(2-tolyl)guanidine
Lamy, Cédric; Moreau, Jacqueline ULg; Dilly, Sébastien ULg et al

Poster (2008, November 17)

Sigma receptors are widely distributed in the central nervous system where they modulate neurotransmitter release, receptor function, ionic channel activity and calcium homeostasis. Two subtypes of sigma ... [more ▼]

Sigma receptors are widely distributed in the central nervous system where they modulate neurotransmitter release, receptor function, ionic channel activity and calcium homeostasis. Two subtypes of sigma receptors have been identified (sigma-1 and sigma-2) with different pharmacological profiles, anatomical distribution and physiological functions. 1,3-Di-(2-tolyl)guanidine (DTG) is a sigma-1 and sigma-2 agonist which is widely used to probe the function of these receptors. It has recently been shown that sigma-1 receptor activation reduces the opening of SK channels in the hippocampus. We have observed that DTG (100 µM) reduces the apamin-sensitive afterhyperpolarization (AHP) of dopaminergic neurons within a slice preparation by ~60%, an effect not observed with other sigma agonists. In addition, neither the selective sigma-1 antagonist BD 1047 (30 µM) nor haloperidol (1 µM) blocked the effect of DTG, which suggested that the inhibition of the AHP might result from a direct block of the underlying SK channels. Whole-cell recordings were made from HEK293 cells transiently transfected with rSK2 or hSK3 cDNA in symmetrical K+ conditions with currents activated by a [Cai] of 1 µM. Expressed SK2 and SK3 channels displayed a classical pharmacology, being blocked by apamin with mean IC50’s of 100 pM and 4 nM, respectively. In contrast, both channel subtypes were blocked with equal sensitivity by N-methyl-laudanosine (NML). DTG inhibited both SK2 and SK3 currents with the same potency (IC50’s were ~30 µM). A mutation that rendered both SK2 and SK3 insensitive to apamin and NML produced a current that was still sensitive to DTG. This direct block of SK channels may be important to consider in relation to the pharmacological effects of this compound. [less ▲]

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See detailModelling soil heterotrophic respiration in an agricultural soil: Model structure and first comparison with experimental data.
Buysse, Pauline ULg; Le Dantec, Valérie; Sagnier, Charlotte et al

Poster (2008, November 17)

Ce travail visait à adapter un modèle de respiration hétérotrophe du sol à un site agricole situé en Hesbaye (Belgique) et cultivé avec une rotation betterave sucrière / blé d’hiver / pomme de terre / blé ... [more ▼]

Ce travail visait à adapter un modèle de respiration hétérotrophe du sol à un site agricole situé en Hesbaye (Belgique) et cultivé avec une rotation betterave sucrière / blé d’hiver / pomme de terre / blé d’hiver. A long terme, ce modèle fera partie intégrante d’un modèle plus important qui décrira la respiration totale du sol et l’évolution du contenu en carbone du sol dans les cultures. Le modèle utilisé dans ce travail est dérivé du modèle Century, possède un pas de temps journalier et couvre une échelle spatiale de l’ordre de l’écosystème. La paramétrisation du modèle a été réalisée sur base d’une recherche bibliographique et de données collectées sur le site Carbo-Europe de Lonzée. Les caractéristiques du sol sont issues d’analyses réalisées sur des sols limoneux, typiques de la région de Hesbaye. Les variables conductrices (variables météorologiques et apports de litière) furent obtenues suite à une campagne de mesures de 4 ans réalisée sur le site expérimental de Lonzée. Les paramètres biochimiques du blé, de la pomme de terre et de la betterave furent tirés de la littérature. Une analyse de sensibilité fut réalisée en vue de classer les différents paramètres par rapport à leur impact sur le taux de respiration et les contenus en carbone de chaque pool. Les paramètres les plus importants étaient ceux contrôlant la réponse à la température, l’apport de litière et les teneurs en lignine et en azote. Des différences d’impact à court et long terme ont aussi été mises en évidence, notamment à cause de la dynamique de stabilisation des pools et des types de résidus de culture. Finalement, cette analyse nous a permis de définir de futures expériences qui seraient nécessaires pour améliorer l’ajustement du modèle sur des données expérimentales. [less ▲]

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See detailPESTEAUX : A project for building GIS-based tool for the assessment of water pollution risks at local scale due to pesticides
Bah, Boubacar Billo ULg; Noël, Stéphanie; Buffet, Dominique et al

Poster (2008, November)

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See detailThe amazing bouncing droplet
Terwagne, Denis ULg; Dorbolo, Stéphane ULg; Vandewalle, Nicolas ULg et al

Poster (2008, November)

When a low viscosity oil droplet is laid onto the surface of a high viscosity oil liquid, it stays at rest for a moment before coalescence. The coalescence can be delayed and sometimes inhibited by ... [more ▼]

When a low viscosity oil droplet is laid onto the surface of a high viscosity oil liquid, it stays at rest for a moment before coalescence. The coalescence can be delayed and sometimes inhibited by injecting fresh air under the droplet. This can happen when the surface of the bath oscillates vertically. In this case the droplet basically bounces on the interface [1, 2]. We observe that the conditions for bouncing depends on the frequency, more precisely we observe resonance when the eigenfrequency of the droplet is excited. Lord Rayleigh expressed the droplet deformation modes in terms of spherical harmonics Y m. We present different l experimental mode of deformation with the corresponding spherical harmonic model. In some conditions, a droplet presents a non axi-symmetric mode of deformation. That leads to a rotation of the droplet and to a horizontal displacement. [less ▲]

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See detailSpatiotemporal Distribution of Polysaccharides During the Mammalian Auditory Organ Development
Thelen, Nicolas ULg; Compère, Philippe; Malgrange, Brigitte et al

Poster (2008, October 31)

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See detailPersistent organic pollutants in wild seabass (Dicentrarchus labrax) from the Northeast atlantic coastal regions and relationship with thyroid hormone levels
Schnitzler, Joseph ULg; Thomé, Jean-Pierre ULg; Das, Krishna ULg

Poster (2008, October 30)

Polychlorinated biphenyls (PCBs) and organochlorine pesticides like Dichloro-Diphenyl-Trichloroethane (DDTs), Hexachlorocyclohexanes (HCHs), Aldrin and Dieldrin were analysed in the muscle of sea bass ... [more ▼]

Polychlorinated biphenyls (PCBs) and organochlorine pesticides like Dichloro-Diphenyl-Trichloroethane (DDTs), Hexachlorocyclohexanes (HCHs), Aldrin and Dieldrin were analysed in the muscle of sea bass (Dicentrarchus labrax) sampled in coastal regions near several important European river mouths (Garonne, Charente, Loire, Seine and Scheldt). These organochlorinated compounds are known to influence the endocrine system of many fish species and mammals and are thus qualified as endocrine disrupters. To highlight a potentially harmful effect of these compounds on the thyroid function of these fishes, we measured the muscular concentrations of thyroid hormones T3 and T4 by Radio-Immuno-Assay. The contamination levels were as follows: the highest concentrations were measured in individuals collected from the coastal region near the Scheldt > Seine > Loire > Charente and the lowest levels were observed in sea bass from coastal regions near the Garonne (from 2422 to 6188 ng.g-1 lw). The measured levels were generally higher than those reported in literature in sea bass from other regions in the Mediterranean Sea. Contamination patterns were different depending on the sampling area and thus the river input of pollutants. The multivariate statistical analysis revealed a significant relationship between the measured persistent organic pollutants and thyroid hormones in muscle. We cannot exclude the assumption that an endocrine disruption of the thyroid related to these pollutants could be the origin of these modifications of the thyroid hormone concentrations. [less ▲]

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See detailMaternal transfer of trace metals to offspring in northern elephant seals
Habran, Sarah ULg; Debier, Cathy; Crocker, Daniel et al

Poster (2008, October 30)

Detailed reference viewed: 41 (13 ULg)
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See detailSequence-Selective inhibition of the DNA binding potencies of Pit-1 and Brn-3 transcription factors by phenyl-furan-benzimidazole DNA ligands
Peixoto, Paul ULg; Depauw, Sabine; Hildebrand, Marie Paule et al

Poster (2008, October 22)

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See detailAN IDENTIFICATION STUDY ON BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS) IN NORTHEAST PATAGONIA, ARGENTINA
Vermeulen, Els ULg; Cammareri, Alejandro; Failla, Mauricio et al

Poster (2008, October 13)

In Argentina, bottlenose dolphin (Tursiops truncatus) sightings decreased notably since the late 80s in regions where it used to be frequent to observe them. Nowadays, Northeast Patagonia is one of the ... [more ▼]

In Argentina, bottlenose dolphin (Tursiops truncatus) sightings decreased notably since the late 80s in regions where it used to be frequent to observe them. Nowadays, Northeast Patagonia is one of the few regions where they still can be seen frequently, although local increasing human activities result in increasing need for information. In general, photo-identification has been established as a helpful tool in cetacean research. However, only few studies have applied this method to bottlenose dolphins in Argentina. This study is therefore aimed to obtain basic information concerning bottlenose dolphins through their identification, this way contributing to their conservation. Land-based observations were made in the northern Gulf of San Matías, Patagonia, Argentina, from August 2006 up to June 2008. Over 15.000 digital pictures of dorsal fins were analysed using the computer assisted identification systems FinEx and FinMatch. Dolphins re-identified during all four seasons in one year were defined as residents. The degree of residency was further estimated by the re-identification frequency (RF); non-resident (RF=1-3) - occasional (RF=4-7) - frequent (RF=8-11) - common (RF¿12). In total, 221 surveys were conducted with an average observation effort of 3.2h per survey, resulting in a total observation effort of 915h of which 124h were spent with 182 dolphin groups. A total of 50 dolphins were identified of which the vast majority (82%) was photographed only in the Natural Protected Area Bahía San Antonio (NPABSA), due to the higher observation effort in this region. Nevertheless, 12% of the catalogued dolphins could be photographed in both NPABSA and the Río Negro estuary, indicating that their home-range might include at least the whole northern region of the Gulf San Matias. Dolphins could be re-identified up to 13 days with 54% showing a degree of residency for NPABSA. This study shows the first data concerning bottlenose dolphins in Northeast Patagonia, but further investigation is highly necessary to improve their conservation. Therefore, the obtained photo-identification catalogue from the presented study is meant to serve as a primary tool for progressing research concerning this species in Argentina. [less ▲]

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See detailRésultats préliminaires d’une étude sur les biopsies rectales prélevées avec une pince à biopsie utérine
Leroux, Aurélia ULg; Amory, Hélène ULg; Van Galen, Gaby ULg

Poster (2008, October 09)

Introduction : La description pratique de la technique de biopsie rectale dans l’espèce équine diffère d’un auteur à l’autre. Pour obtenir des échantillons représentatifs, il est souvent suggéré effectuer ... [more ▼]

Introduction : La description pratique de la technique de biopsie rectale dans l’espèce équine diffère d’un auteur à l’autre. Pour obtenir des échantillons représentatifs, il est souvent suggéré effectuer les biopsies à l’aveugle au moyen d’une pince à biopsie utérine plutôt que par endoscopie rectale. Les sites de prélèvement préconisés sont variables. Même si tous les auteurs s’accordent à dire qu’il faut réaliser la biopsie en arrière du cul-de-sac rétropéritonéal [1] [2], la distance de prélèvement en avant de l’anus varie de 15 cm [2] [5] à 30 cm [1] [3]. De plus, le prélèvement est réalisé tantôt au plafond [1] [5], tantôt au plancher [3] du rectum. De nombreux auteurs évoquent le très faible risque de complication suite à la biopsie rectale [1] [4], mais la perforation, l’abcès périrectal et la péritonite septique ont été décrits [2]. Objectifs : Le but de cette étude est d’évaluer les risques associés à la technique de biopsie rectale réalisée au moyen d’une pince à biopsie utérine. Méthodes : Cette étude a été effectuée sur 11 chevaux destinés à l’euthanasie : les 7 premiers ont été biopsiés sous anesthésie générale, et les 4 autres ont été biopsiés debout sous tranquillisation (0,01mg/kg détomidine IV ou 0,6mg/kg xylazine IV). Résultats : Aucun des 4 chevaux biopsiés debout n’a montré de signes de douleur au cours de la procédure. Pour un droitier, il s’est avéré plus facile d’effectuer la biopsie rectale avec la pince dans la main droite et la muqueuse rectale dans la main gauche et de prélever à 2H. Discussion et conclusions : La biopsie rectale est facile à faire et bien supportée sur le cheval tranquillisé, bien qu’elle soit fréquemment associée à des hémorragies locales. Le prélèvement devrait être fait à moins de 15 cm de profondeur pour réduire les risques de péritonite. Il est en outre conseillé d’effectuer les biopsies à 10H (gaucher) ou 2H (droitier) pour faciliter techniquement l’acte et réduire les risques d’hématomes. Attendu que l’euthanasie a été effectuée juste après les biopsies, le développement éventuel d’autres complications n’a pas été évalué dans cette étude. Dans une étude suivante, l’aspect histologique des prélèvements obtenus par biopsie sera évalué et comparé à celui obtenu post-mortem. References 1. BRAZIL T. (2007) How to: duodenal and rectal biopsy, BEVA Congress 2007 Proceedings, 66-67. 2. DEBOWES R.M. (1991) Standing rectal and tail surgery, Vet. Clin. North Am. Equine Pract., 7 : 3, 649-667. 3. LINDBERG R., NYGREN A., PERSSON S.G.B. (1996) Rectal biopsy diagnosis in horses with clinical signs of intestinal disorders: a retrospective study of 116 cases. Equine Vet. J., 28 : 4, 275-284. 4. PLUMMER P.J. (2006) Malabsorptive maldigestive disorder with concurrent Salmonella in a 3-year-old quarter horse. Vet. Clin. North Am. Equine Pract., 22 : 1, 85-94. 5. TAMZALI Y. (2006) Chronic weight loss syndrome in the horse: a 60 case retrospective study. Equine Vet. Educ., 18 : 6, 289-296. [less ▲]

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See detailVorticity balance in the Northwestern African Upwelling
Troupin, Charles ULg; Mason, Evan; Sangrà, Pablo

Poster (2008, October 06)

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See detailBiogeochemical Investigations of Coccolithophore Blooms along the Continental Margin of the Northern Bay of Biscay: Highlights of the PEACE Project
Chou, Lei; Harlay, Jérôme ULg; De Bodt, Caroline et al

Poster (2008, October 06)

Recent studies have demonstrated that changing ocean chemistry due to ocean acidification poses a growing threat for marine organisms such as corals, coccolithophores and many others that form calcareous ... [more ▼]

Recent studies have demonstrated that changing ocean chemistry due to ocean acidification poses a growing threat for marine organisms such as corals, coccolithophores and many others that form calcareous skeletons. Its biogeochemical feedbacks and impact on the oceanic carbon cycle are yet to be quantified. Coccolithophores are the major calcifying phytoplankton in the sub-polar and temperate regions of the world’s ocean. They produce furthermore transparent exopolymer particles (TEP), which are known to promote aggregate formation. Combined with the CaCO3 ballast effect, large-scale coccolithophore blooms could thus contribute to the export of organic carbon to deep waters on relatively short time scales. During the Belgian PEACE project, we have conducted yearly interdisciplinary biogeochemical surveys, assisted by remote sensing, along the continental margin of the northern Bay of Biscay where coccolithophore blooms dominated by Emiliania huxleyi are frequently and recurrently observed (Figure 1). Rates of various processes governing the coccolithophore ecosystem dynamics have been determined and associated biogeochemical parameters analysed. The overall objective is to evaluate the role in climate regulation of calcification, primary production and export processes during coccolithophore blooms. Here we report the principal results obtained during the 2006 campaign. [less ▲]

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See detailIntegration of Accurate 2D Inundation Modelling, Vector Land Use Database and Economic Evaluation
Ernst, Julien ULg; Dewals, Benjamin ULg; Archambeau, Pierre ULg et al

Poster (2008, October 02)

Within the global framework of the climate change, according to most Regional Climate Mod-els the maximum peak discharges in river will increase in importance and frequency. Therefore the people will have ... [more ▼]

Within the global framework of the climate change, according to most Regional Climate Mod-els the maximum peak discharges in river will increase in importance and frequency. Therefore the people will have to face worst inundation conditions. In order to protect themselves from the increasing flood risk, the communities have to draw up suitable flood protection measures. The selection and the evaluation among the different possible flood mitigation measures requires developing decision-support system (DSS). This sys-tem has to take into consideration parameters such as hydraulic, economic, social or environmental. This pa-per focuses on the integration between two components of the DSS, namely the evaluation of the economic impacts of floods and the hydrodynamic modelling. The hydraulic simulations are conducted by means of WOLF 2D flow modelling system and provide as an output high resolution flood maps detailing the distribu-tion of water depth and flow velocity in the floodplains. The integration is ensured by the use of very accurate geographic databases and an automated procedure which makes the most of geomatic methods. The paper de-tails the application of the integrated assessment procedure for a case study along the river Ourthe located in the Meuse basin (Belgium). Moreover, possibilities of validation of the economic damage evaluation proce-dure are investigated by comparing computation results with real damage data recorded by the Belgian Disas-ter Fund after several major flood events (2003, 2002, 1995, and 1993). [less ▲]

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See detailReconstruction of Missing Satellite Total Suspended Matter Data over the Southern North Sea and English Channel using Empirical Orthogonal Function Decomposition of Satellite Imagery and Hydrodynamical Modelling
Sirjacobs, Damien ULg; Alvera Azcarate, Aïda ULg; Barth, Alexander ULg et al

Poster (2008, October)

Optical remote sensing data archives generally have many gaps caused by clouds or other retrieval problems. However, for the light forcing of ecosystem models continuous fields are required. For ... [more ▼]

Optical remote sensing data archives generally have many gaps caused by clouds or other retrieval problems. However, for the light forcing of ecosystem models continuous fields are required. For parameters exhibiting strong spatial and temporal correlations for regions of similar dynamics or from day to day, the missing data can be estimated by use of statistical techniques. In this context, the Data Interpolation with Empirical Orthogonal Functions (DINEOF) method is used for reconstruction of complete space-time information for surface total suspended matter (TSM) and chlorophyll a from a 5-year archive of MODIS and MERIS products over the Southern North Sea and English Channel. The DINEOF univariate methodology has been previously demonstrated for Mediterranean sea surface temperature data (Alvera-Azcarate et al., 2005, Beckers et al., 2006). Alvera-Azcarate et al (2007) showed that SST reconstructions could be improved by using a multivariate approach in which SST, chlorophyll and wind fields were taken into account together for the analyses. Here, TSM images will be used in combination with information from the COHERENS hydrodynamical model to provide a complete and continuous estimate of surface TSM for the Southern North Sea throughout the period 2003-2005. In addition to the remotely sensed TSM, the DINEOF multivariate analysis will consider wind fields, depth integrated currents, surface elevations and bottom stresses. Reconstucted images are compared with the original incomplete images. Validation of the method is achieved by estimation of information removed from the training data by exclusion of entire images and by addition of artificial clouds. The data reconstruction technique has further applications in the processing and quality control of optical remote sensing data. Perspectives will be outlined for improving the quality control of retrieved parameters and for the improvement of retrievals by adding statistical information to the conventional spectral processing. References: Alvera-Azcarate, A., Barth, A., Rixen, M., and Beckers, J.-M.: Reconstruction of incomplete oceanographic data sets using Empirical Orthogonal Functions. Application to the Adriatic Sea, Ocean Modelling, 9, 325–346, 2005. Alvera-Azcarate, A., Barth, A., Beckers, J. M., and Weisberg, R. H.: Multivariate Reconstruction of Missing Data in Sea Surface Temperature, Chlorophyll and Wind Satellite Fields, Journal of Geophysical Research, 112, C03008, doi:10.1029/2006JC003660, 2007. Beckers J.-M., A. Barth & A. Alvera-Azcarate, DINEOF reconstruction of clouded images including error maps. Application to the Sea-Surface Temperature around Corsican Island, Ocean Sciences, 2: 183–199, 2006. [less ▲]

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See detailImage Quality, Accuracy of Attenuation and Scatter Corrections of the microPET Focus 120 Using the NEMA NU4-2008 Phantom
Bahri, Mohamed Ali ULg; Plenevaux, Alain ULg; Seret, Alain ULg

Poster (2008, October)

This work aimed at evaluating the image quality and the accuracy of attenuation and scatter corrections methodologies provided with the microPET Focus 120 scanner. The protocol used here is described in ... [more ▼]

This work aimed at evaluating the image quality and the accuracy of attenuation and scatter corrections methodologies provided with the microPET Focus 120 scanner. The protocol used here is described in the forthcoming NEMA NU4-2008 document. This study included 1 h transmission experiments, with two sources (68Ge and 57Co, both one half-live old), in coincidence mode (Ge) with and without windowing, and singles mode (Ge and Co). Transmission data with Co were also collected for shorter acquisition times (515/1030/2060 s). Transmission with scatter correction, and emission with attenuation with or without scatter correction, slices were reconstructed using 2D-FBP (ramp filter). The uniformity, the recovery coefficients (RC) and the accuracy of corrections were evaluated as described in the NEMA document. We also determined the attenuation coefficient (AC) for water using the methodology applied to measure the mean pixel value for the emission slices of the uniform part of the phantom. The Co single mode measurements provided a mean AC for water closer to the theoretical value than the Ge measurements either in single or in coincidence mode even for the shortest acquisition time. Moreover, the lowest coefficients of variation per pixel of the uniform slices were measured for attenuation corrected data based on Co measurements. Also, spill-over ratio for non-emitting air and water compartments reflected a higher capability of this attenuation correction method for scatter correction. The RC measured on emission image corrected only for attenuation did not show any significant difference linked to the transmission measured methods. However, higher RC values were noted for Ge coincidence with windowing when emission data were corrected for both attenuation and scatter. Hence, Co singles transmission seems to be the most suitable method for attenuation correction on the microPET Focus 120 scanner. [less ▲]

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See detailOntogenetic determinism of colour polymorphism in a coral reef fish, Chrysiptera brownriggii (Pomacentridae)
Frederich, Bruno ULg; Brié, Christophe; Santos, Raphael et al

Poster (2008, October)

The determinism of ontogenetic colour changes induced by environmental factors is poorly understood in marine fishes, especially in coral ecosystems. The present study, conducted at the Rangiroa Atoll ... [more ▼]

The determinism of ontogenetic colour changes induced by environmental factors is poorly understood in marine fishes, especially in coral ecosystems. The present study, conducted at the Rangiroa Atoll (French Polynesia) explored the effects of fish density and brightness/darkness condition (type of background) on colour determination during the ontogeny of a territorial damselfish Chrysiptera brownriggii (Bennett 1828). In this species, larvae always colonize the reef (settlement) in a yellow morph, while juveniles and adults can display two distinct colour-patterns: yellow and dark brown. Our experiments in aquaria showed that a significant higher proportion of C. brownriggii larvae turned into the brown morph in a dark condition during a period of 5 and 15 days (70-100% of brown morph induction) just after reef settlement. A significant positive effect of fish density inducing a brown colour morph was also highlighted. After a first colour induction, reversibility experiments illustrated that juveniles can change their colour morph anew after a 5-day period. Although a shift from brown to yellow morph seemed to be more limited. In the dark condition, yellow adults did not change their colour after a 5-day period. Our results showed that the colour dimorphism in C. brownriggii should be density-dependent. The period of sensitivity seems to last throughout the post-settlement period. We suggest that the yellow morph in C. brownriggii can be viewed as a paedomorphic trait. Overall, our results reveal that a darkness/lightness environment and fish density are environmental cues related to colour determinism in the polyphenetic C. brownriggii. [less ▲]

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See detailDevelopment of a strategy to study toxicodynamic of pollutants in spawning sea turtles from the French West Indies
Dyc, Christelle ULg; Bouquegneau, Jean-Marie ULg; De Pauw-Gillet, Marie-Claire ULg et al

Poster (2008, October)

Sea turtles including the green turtle Chelonia mydas and the hawksbill turtle Eretmochelys imbricata are critically endangered species, facing different factors as marine pollution. There is a blatant ... [more ▼]

Sea turtles including the green turtle Chelonia mydas and the hawksbill turtle Eretmochelys imbricata are critically endangered species, facing different factors as marine pollution. There is a blatant lack of data dealing with toxicants such as metals and persistent organic pollutants (POPs) in sea turtles. We developed a strategy to apprehend levels, effects and transfer to offspring of several pollutants in sea turtles. Sampling of blood, subcutaneous tissue and eggs of 15 gravid C. mydas and E. imbricata was carried out between July and September 2008 in Martinique (Diamant’s beach) and Guadeloupe (Petite Terre and Marie-Galante). Blood was collected from the dorso-cervical sinus and subcutaneous tissue was sampled in shoulder of the spawning females using a 5 mm biopsy punch (Kai Europe GmbH, Germany). Total blood and serum were successfully taken for metal, POP and biomarker investigations. T-mercury was analyzed by DMA milestones while PCBs, DDT and chlordecone were analyzed by EDC Ni63 high performance gas chromatography HPLC. Samples of serum were analyzed for vitamins (A and E) by HPLC and for thyroid hormones (triiodothyronine and thyroxine) by radioimmunoassay. In parallel to this field study, a cell model using 3T3-L1 cell line was built up to test in vitro effects of PCBs and mercury as well as the relationship between in vitro exposure and fat mobilization. Preliminary results showed a dose-response relationship between increased Aroclor 1234 and 1252 concentrations (0.5 ppb, 1 ppb and 1.5 ppb) and adipocyte mortality (Nucleocounter). The strategy we propose here will bring further insights on levels and potential impact of pollutants on female sea turtles and their offspring. [less ▲]

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See detailIn-situ SAXS of resorcinol-formaldehyde gel formation: either colloid aggregation or microphase separation
Gommes, Cédric ULg; Roberts, Anthony; Goderis, Bart

Poster (2008, October)

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See detailSimulation based energy consumption calculation of an office building using solar-assisted air conditioning
Thomas, Sébastien ULg; Andre, Philippe ULg

Poster (2008, October)

To minimize environmental impact and CO2 production associated with air-conditioning system operation, it is reasonable to evaluate the prospects of a clean energy source. The targets of the study are to ... [more ▼]

To minimize environmental impact and CO2 production associated with air-conditioning system operation, it is reasonable to evaluate the prospects of a clean energy source. The targets of the study are to evaluate cooling energy consumption to maintain thermal comfort in an office building and to point out solar energy to satisfy these cooling needs. Simulations were carried out with three different cooling systems in the same operating conditions to determine as accurately as possible the potential use of solar energy. For comparison purpose, the base case is a classical air-conditioning system (heat pump for cooling, gas boiler for heating). Two other configurations were simulated: a classical vapour compression system fed by photovoltaic panels and electricity grid as back-up and, absorption chiller fed by solar thermal panel field and by gas boiler. In the three chosen locations (Paris, Lisbon and Stockholm), results shown that installing photovoltaic panels on the roof is really interesting from the primary energy consumption point of view. [less ▲]

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See detailTesting methods applicable to refrigeration components and systems
Quoilin, Sylvain ULg

Poster (2008, October)

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See detailPotential use of Paracentrotus lividus as bioindicator for recent trace element pollution monitoring
Richir, Jonathan ULg; Gobert, Sylvie ULg; Bouquegneau, Jean-Marie ULg

Poster (2008, October)

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

The Mediterranean Sea is an enclosed basin, highly submitted to anthropogenic pressures. Chemical pollution originating from coastal urban centres and industries, or carried by air and rivers, will primarily affect its coastal ecosystems. The pollution by trace elements into the marine environment is rapidly evolving further to the recent modifications of their production and industrial uses by men. As a result, some trace elements that were previously poorly studied can be considered now as environmental pollutants, whose concentrations can sometimes be way above their natural baseline levels. The purple sea urchin Paracentrotus lividus is a well know bioindicator used for metal pollution monitoring (Fe, Cd, Cr, Pb, Zn and Cu) along the Mediterranean and Atlantic coasts. This sedentary organism successfully concentrates the pollutants diluted in its environment, and the measured concentrations reflect properly the health status of the ecosystem. This study is a first approach on the use of P. lividus as bioindicator for some less investigated trace elements (Al, V, Mn, Co, Ni, Se, Mo and Ag), chosen for their potential toxic effects. We have compared the element concentrations of the digestive tract tissues and gonads of female and male sea urchins. The organisms were frozen prior to dissection, or they were dissected alive, the two experimental procedures being compared afterwards. The existence of an eventual relationship between their gonadic index or their test diameter and the measured pollutant concentrations was also investigated. [less ▲]

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See detail. Do innervation of germinal centre and contacts between FDC and nerve fibers be keys to understand the susceptibility difference between bovines and humans to the BSE agent?
Defaweux, Valérie ULg; Dorban, G.; Antoine, Nadine ULg et al

Poster (2008, October)

Background: In regard to BSE and vCJD, the agent tropism for lymphoid tissues is completely different even if the infectious strain responsible and the way of inoculation are identical. During vCJD, the ... [more ▼]

Background: In regard to BSE and vCJD, the agent tropism for lymphoid tissues is completely different even if the infectious strain responsible and the way of inoculation are identical. During vCJD, the infectious agent crosses the digestive barrier and multiplies in lymphoid organs, before progressively reaching the brain. Indeed, in vCJD, it accumulates in the ileum, tonsils, spleen and appendix of infected individuals. In contrast, in cattle, the BSE agent has a low affinity for lymphoid tissues and mainly accumulates in the nervous system. During preclinical stages, infectivity, other than that in the peripheral nervous system or central nervous system, is confined in the distal ileum of orally infected cattle. So, it appears that, at least in the case of BSE and vCJD, host properties can influence the accumulation of the infectious agent in lymphoid organs. Objectives and methods: In this study, we analysed by confocale microscopy the mucosal innervation and the interface between nerve fibres and FDC in bovine and human tonsils using a panel of antibodies. Since differences in the innervation of lymphoid organs depending on species and on age have been reported, we analysed two categories of bovines (calves less than 12 months old and bovines older than 24 months) and two categories of humans (patients less than 5 years old and patients older than 25 years). Results: In both species, ways of innervation by-passing germinal centres could be postulated: nerve fibres are widely distributed in antigen/cell traffic area: the lamina propria, the interfollicular zone and the lymphoepithelial area. We pointed out that, only in tonsils of bovines older than 24 months, nerve fibres are observed to be in contact with FDC. In contrast, in human tonsils, no nerve fibres established contacts with FDC, whatever the age. Discussion: Innervation of germinal centres can be said to be an age-dependent dynamic process in bovines. The weak innervation of the secondary lymphoid organs could thus be a rate-limiting step to neuroinvasion in humans. This species difference could influence the way of neuroinvasion and thus, the susceptibility of bovines and humans to the BSE agent. [less ▲]

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See detailIn vitro modelisation of prions neuroinvasion mediated by dendritic cells
Dorban, G.; Defaweux, Valérie ULg; Heinen, Ernst ULg et al

Poster (2008, October)

Detailed reference viewed: 15 (10 ULg)