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See detailEvaluation of sedation depth and quality of performed procedures following administration of α2-agonists combined or not with butorphanol in horses.
Barbry, Stephanie; Verwilghen, Denis ULg; Van Galen, Gaby ULg et al

Poster (2008, October)

Several molecules available in equine medicine provide profound sedation and good analgesia when performing diagnostic or surgical procedures. They differ slightly in degree of action, as well in time as ... [more ▼]

Several molecules available in equine medicine provide profound sedation and good analgesia when performing diagnostic or surgical procedures. They differ slightly in degree of action, as well in time as in depth. The aim of this study was to evaluate the depth of sedation and quality of performing a standardized procedure after injection of an 2-agonist alone or associated with butorphanol. Horses presented to the Equine Clinic of Liege University from December 2007 to June 2008 for an endoscopic, dental, radiological or ophthalmological examination of which owner and clinician agreed to include the horse in the study were retained. All horses (n=133) were sedated in a randomized double blind fashion using one of the six following protocols: detomidine (D) (0.01mg/kg IV), romifidine (R) (0.04mg/kg IV), or xylazine (X) (0.5mg/kg IV) alone or associated with butorphanol (B) (0.02mg/kg IV). Stability, head position and the reaction to a stimulus (auditive and visual) were evaluated before the start of the procedure. An overall subjective grade using a 10 cm line scale was given to evaluate sedation depth (ranging from no effect to maximal depth on line) and the quality of the performed procedure (ranging from not realised to ideal examination). For each specific procedure, the same clinician experienced in his particular field evaluated the parameters. Data were related by a variance analysis using SAS system and considered significant if P<0.01. The used protocols significantly influenced both sedation depth and examination quality. Sedation depth increased significantly when B was added in all the three 2-agonists used (mean ± SD): D: 6.46±0.33; D+B: 7.06±0.37; R: 4.93±0.46; R+B: 7.04±0.45; X: 4.94±0.43; X+B: 7.75±0.40. Detomidine provided a significantly better quality of the examination compared to romifidine and xylazine. The addiction of butorphanol significantly decreased the examination quality when added to detomidine and increased the quality when combined with romifidine and xylazine. Mean (± SD) of the quality of performed procedures: D: 8.41±0.54; D+B: 6.06±0.64; R: 6.68±0.71; R+B: 7.16±0.67; X: 4.47±0.67; X+B: 4.52±0.64. Comparison of sedation depth and quality of performed examination revealed an increase in quality of examination scores with increasing depth of sedation until a certain level. As from sedation depths with scores of 8 or more, a decrease in quality of examination was encountered. This report shows the important effect of butorphanol addition on sedation. However, increasing sedation depth was not necessarily linked to a better quality of procedure, notably due to difficulties in handling strongly sedated horses for the procedures performed in this study. [less ▲]

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See detailModélisation hydrodynamique 2D et SIG à haute résolution pour l’évaluation de mesures de protection contre les inondations en milieu urbain
Ernst, Julien ULg; Dewals, Benjamin ULg; Archambeau, Pierre ULg et al

in 3e journées doctorales en hydrologie urbaine (2008, October)

Within the global framework of climate change, the majority of the regional climatic models (RCM - Regional Climatic Model) predict an increase in the frequency and importance of the rainy events ... [more ▼]

Within the global framework of climate change, the majority of the regional climatic models (RCM - Regional Climatic Model) predict an increase in the frequency and importance of the rainy events. Therefore, the populations will have to face an increased risk of flooding. In order to draw up suitable protection strategy in this context, decision-making tool must be developed to select the adequate mitigation measure among the whole of the possible protection measures. This system has to take into account parameters such as hydraulic economic, social or environmental. This paper focuses on the integration between the economic evaluation of the undergone damage and the two-dimensional hydrodynamic modelling implemented using the model WOLF 2D. The integration is ensured by the use of pointed geographical information systems and an automated procedure, based on the methods of geomatic, guaranteeing a perfect applicability of methodology for the analysis of urban areas. The whole of methodology is then applied to the evaluation of a measurement of adaptation to Ourthe (basin of the Meuse), namely the rehabilitation of an old channel formerly used to allow the river transport to the river. [less ▲]

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See detailCharacterization of copper grain growth limitations inside narrow wires depending of overburden thickness
Dubreuil, Olivier ULg; Cordeau, Maryline; Mourier, Thierry et al

in Microelectronic Engineering (2008, October), 85(10), 1988-1991

With the downscaling of feature dimensions, copper interconnects exhibit properties differing from bulk or film material. Resistivity increases and limits electrical performances, and reliability of ... [more ▼]

With the downscaling of feature dimensions, copper interconnects exhibit properties differing from bulk or film material. Resistivity increases and limits electrical performances, and reliability of interconnects becomes a more important challenge for each new technological node. In this study, we present an approach of copper grain growth control inside narrow wires by adding a step between the copper electro-chemical deposition (ECD) and the chemical–mechanical polishing (CMP). This step corresponds to a partial CMP step (pre-CMP) and is applied after ECD and before anneal in order to modify the copper previous termoverburdennext term thickness. Depending on the targeted thickness, copper grain growth occurs during anneal with different efficiencies. Crystallization and grain growth behavior inside wires is investigated with focused ions beam (FIB). We present here our methodology for sample preparation and characterization. Results are focused on electrical variations and on morphological aspects of copper crystallization and grain growth inside lines observed with various overburden thicknesses. [less ▲]

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See detailEcology and silviculture of black alder (Alnus glutinosa (L.) Gaertn.)
Claessens, Hugues ULg; Oosterbaan, Anne; Savill, Peter

Poster (2008, October)

Black alder (Alnus glutinosa (L.) Gaertn.) is widespread across Europe, both in forest and on open land along the watercourses. It plays a major role in nature conservation, thanks to its relation with ... [more ▼]

Black alder (Alnus glutinosa (L.) Gaertn.) is widespread across Europe, both in forest and on open land along the watercourses. It plays a major role in nature conservation, thanks to its relation with the river ecosystems and its network distribution on open land. [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 detailSpatial heterogeneity at small scale in the microbenthic loop of Posidonia oceanica meadows
Pete, Dorothée ULg; Lenartz, Fabian ULg; Velimirov, Branko et al

Conference (2008, October)

In the Mediterranean coastal zone, one the most important ecosystem is the Posidonia oceanica meadow. This seagrass is endemic of the Mediterranean Sea and plays many important ecological roles like ... [more ▼]

In the Mediterranean coastal zone, one the most important ecosystem is the Posidonia oceanica meadow. This seagrass is endemic of the Mediterranean Sea and plays many important ecological roles like oxygen production, nursery for numerous commercial species of fishes and protection of coastal zones by reducing the impact of waves. However, there is a severe lack of informations on small scale variations in its sediment compartment. In an attempt to understand spatial variations in the microbenthic loop (bacteria, organic matter, microphytobenthos and meiofauna) of this ecosystem, an experiment was led in Calvi Bay (Corsica, France), in March 2008, at 10 m depth. Twelve points were sampled randomly in a 125 x 125 cm grid, divided into twenty-five 25 x 25 cm squares, to assess and describe the spatial distribution and variations of different parameters of the sediment. Those parameters are granulometry, density of the P. oceanica meadow, nutrients concentration in pore water, bacteria (biomass, abundance, morphotypes), organic matter (biomass), microphytobenthos (biomass), roots and rhizomes (biomass) and meiofauna (biomass). Distribution maps were produced using the DIVA (Data-Interpolating Variational Analysis) method. Our results prove that the sediment compartment is highly heterogeneous at small scale, especially for bacteria and in the first centimeter of sediment cores. Moreover, a correlation has been established between microphytobenhtos variations and phosphate concentration in pore water. For the first time, such small scale variations are depicted in a P. oceanica meadow, which underlines the importance to take them into account in sampling strategies. [less ▲]

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See detailCharacterization of prolatinomas resistant to dopaminergic agonists
Vroonen, Laurent ULg; Tamagno, G.; Naves, L. et al

in 18th Meeting of the Belgian Endocrine and Metabolic societies : Bruxelles, 25 octobre 2008 (2008, October)

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See detailCyclin dependant kinase inhibitor 1B (CDKN1B) gene mutations in familial isolated pituitary adenomas (FIPA) : Analysis in 84 families
Apetrii, P.; Tikhomirova, M.; Daly, Adrian ULg et al

in 18th Meeting of the Belgian Endocrine and Metabolic societies : Bruxelles, 25 octobre 2008 (2008, October)

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See detailHistopathological comparison of two mouse-adapted influenza A strains in mice.
Garigliany, Mutien-Marie ULg; Habyarimana, Adélite; Cornet, Anne et al

Conference (2008, October)

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See detailPhilosophie politique et approche pragmatique du politique en contexte islamique. Lecture d’al-Mâwardi
Nachi, Mohamed ULg

in Gandolfi et Levi, Paola et Giovani (Ed.) Entre théologie et Politique: Les origines théologiques cachées de la pensée politique contemporaine dans les pays de la Méditerranée (2008, October)

Montrer l'apport d'al-Mâwardi pour le développement d'une approche pragmatique du politique en contexte islamique

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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 detailIntrasaccular injection of aminoglycosides: a novel method for temporary damaging fish inner ear hair cells
Faucher, Karine ULg; Aas-Hansen, Øyvind; Damsgard, Borge et al

Poster (2008, October)

Fish models are increasingly being used for hearing research investigations. Aminoglycoside antibiotics that are used for damaging the inner ear hair cells can have systemic side effects leading to death ... [more ▼]

Fish models are increasingly being used for hearing research investigations. Aminoglycoside antibiotics that are used for damaging the inner ear hair cells can have systemic side effects leading to death of study animals. This study aimed to compare two methods: i) systemic (intravenous) and ii) local (intrasaccular) gentamicin administration for induction of inner ear hair cell damage in the Atlantic cod, Gadus morhua (L.). Hair cell damage was assessed using scanning electron microscopy; hair cell density, prevalence of immature hair cells and kinocilia length were measured. Gentamicin-treated fish were compared with control and sham fish. Intravenous gentamicin led to dose-dependent mortality caused by nephrotoxicity. The only visible effect after treatment was more immature hair cells and shorter kinocilia, the effect on hair cell density was equivocal. Following intrasaccular gentamicin treatment, fish mortality was negligible, and hair cells were damaged regardless of dose. Here, we observed decreased hair cell density, high prevalence of immature hair cells, and significantly shortened kinocilia. Conclusion: intrasaccular injection is preferable to intravenous injection of gentamicin for the study of ototoxicity in the Atlantic cod. [less ▲]

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See detailInterdomain Traffic Engineering in a Locator/Identifier Separation Context
Saucez, Damien; Donnet, Benoît ULg; Iannone, Luigi et al

in IEEE Internet Network Management Workshop (2008, October)

The Routing Research Group (RRG) of the Internet Research Task Force (IRTF) is currently discussing several architectural solutions to build an interdomain routing architecture that scales better than the ... [more ▼]

The Routing Research Group (RRG) of the Internet Research Task Force (IRTF) is currently discussing several architectural solutions to build an interdomain routing architecture that scales better than the existing one. The solutions family currently being discussed concerns the addresses separation into locators and identifiers, LISP being one of them. Such a separation provides opportunities in terms of traffic engineering. In this paper, we propose an open and flexible solution that allows an ISP using identifier/locator separation to engineer its interdomain traffic. Our solution relies on the utilization of a service that transparently ranks paths using cost functions. We implement a prototype server and demonstrate its benefits in a LISP testbed. [less ▲]

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See detailConduite à tenir face a un cas de myopathie atypique du cheval au pré
Van Galen, Gaby ULg; Serteyn, Didier ULg; Marcillaud Pitel, Chistel et al

(2008, October)

Owing to the systematic recording of epidemiological and clinical data of European cases of atypical myopathy via the « Atypical Myopathy Alert Group » (AMAG) risk factors for AM have been recognized ... [more ▼]

Owing to the systematic recording of epidemiological and clinical data of European cases of atypical myopathy via the « Atypical Myopathy Alert Group » (AMAG) risk factors for AM have been recognized. Preventive measures may be advised from the identified demographic, managemental and environmental risk factors for atypical myopathy. From the clinical course of affected horses and the review of the lately published scientific papers, a symptomatic treatment is proposed as well as a supportive therapy based on the recently identified pathological process involved in atypical myopathy. [less ▲]

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See detailSpatial and interannual variability of the Schyphozoan medusae, Pelagia noctiluca (Forksål), in the Bay of Calvi (Corsica)
Collignon, Amandine ULg; Goffart, Anne ULg; Lejeune, Pierre et al

Poster (2008, October)

The temporal distribution of the Schyphozoan medusae Pelagia noctiluca (Forksål) has been examined weekly in the oligotrophic coastal waters of the Bay of Calvi (Corsica) from 2003 to 2008. The ... [more ▼]

The temporal distribution of the Schyphozoan medusae Pelagia noctiluca (Forksål) has been examined weekly in the oligotrophic coastal waters of the Bay of Calvi (Corsica) from 2003 to 2008. The observations show a gradual increase of jellyfish number in 2004 to 2005, followed by a dramatic increase in the 2006 and a significant reduction in summers 2007 and 2008. The numeration of ephyra larvae in plankton and ovarian histology show a higher reproduction in June 2006. An analysis of the spatial distribution of the Pelagia noctiluca in the area of the Bay of Calvi emphasises that during the 2006 bloom, most of the organisms are present at a distance of the coastline where they are forming actives swarms of 200 m of length with 5 to 10 individual per m3. In the swarms, the individuals are healthful and swim actively in the upper layer (10 t 60 m) with tentacles extended, probably catching the food. The swarms are generally located around wind-protected area where the surface turbulence is reduced and where zooplankton is accumulating. Sometimes, the swarms migrate vertically probably in relation with changes of wind conditions. In some cases, moribund individuals partially destroyed or at the end of their biological cycle escape from active swarms and drift passively, at the surface, under the action of water movements, into coastal waters and beaches where they accumulate and reach 200 individual per m3. In these passive swarms the individuals continue to swim slowly but are actively fed by some Sparid fish. [less ▲]

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See detailEVALUATION OF EARTHQUAKE- TRIGGERED LANDSLIDES IN EL SALVADOR USING A GIS- BASED NEWMARK MODEL
Garcia-Rodriguez, MJ; Havenith, Hans-Balder ULg; Benito, B.

in The 14th World Conference on Earthquake Engineering (2008, October)

In this work, a model for evaluating earthquake-triggered landslides hazard following the Newmark methodology is developed in a Geographical Information System (GIS). It is applied to El Salvador, one of ... [more ▼]

In this work, a model for evaluating earthquake-triggered landslides hazard following the Newmark methodology is developed in a Geographical Information System (GIS). It is applied to El Salvador, one of the most seismically active regions in Central America, where the last severe destructive earthquakes occurred in January 13th and February 13th, 2001. The first of these earthquakes triggered more the 500 landslides and killed at least 844 people. This study is centred on the area (10x6km) where the most tragic landslide occurred (Las Colinas landslide). The model is based on the Newmark method, which treats a potential landslide as a rigid block sliding on an inclined plane. It requires inputs characterizing the geological conditions and the intensity of earthquake ground motions. The procedure includes factors such as earthquake magnitude, source-site distance, strength of geologic materials, ground water conditions and slope. The data set used in the application includes an earthquake-triggered landslides inventory for the 2001 earthquakes, a 1:100,000-scale geologic map of the region, digital cartography, strong-motion records, data on engineering properties of geologic units, and high-resolution (10 m) digital elevation models of the topography, all of them integrated in the GIS. Displacements of possible landslides along the slope (Newmark displacements) are computed from the Arias Intensity (Ia), and the Critical Acceleration (ac); the latter is inferred from the Factor of Safety (Fs). Newmark displacements have been applied to predict a landslide hazard map at regional scale, in areas where ground-shaking and geological conditions are well known. [less ▲]

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See detailTransect GLACIOCLIM-SAMBA : observation et modélisation du Bilan de Masse de Surface sur la zone de transition côte-plateau Antarctique
Agosta, Cécile ULg; Genthon, Christophe; Favier, Vincent et al

Conference (2008, October)

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See detailTwo novel mutations of the calcium sensing receptor gene
Livaradiu, E.; Rydlewski, C.; Hamoir, Etienne ULg et al

in 18th Meeting of the Belgian Endocrine and Metabolic societies : Bruxelles, 25 octobre 2008 (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 detailUne copie en maġribī du Kitāb al-Faraj baʿd aš-Šidda d'at-Tanūḫī
Franssen, Elise ULg

Poster (2008, September 26)

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See detailCoronography with a dynamic hologram
Ricci, Davide ULg; Le Coroller, Hervé; Piron, Pierre ULg

Poster (2008, September 26)

An innovative solution to improve the performances of coronagraphs consists in adding, in the optical scheme, a dynamic hologram removing most of the residual speckle starlight. Our simulations show that ... [more ▼]

An innovative solution to improve the performances of coronagraphs consists in adding, in the optical scheme, a dynamic hologram removing most of the residual speckle starlight. Our simulations show that the detection limit in the flux ratio between a host star and a very near planet, in the case of wavefront bumpiness imperfections at lambda/20 (resp. lambda/100), improves over a factor 1000 (resp. 10000) when equipped with a hologram, allowing to direct image an exo-Earth at a distance of 11 parsec with a 6.5m space telescope. [less ▲]

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See detailEmerging International Standards : If a dream could come true
Michel, Quentin ULg

Conference (2008, September 25)

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See detailOn mathematical concepts for the material world
Leclercq, Bruno ULg

Conference (2008, September 25)

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See detailReflection spheres of the public, social and cooperative economy
Fecher-Bourgeois, Fabienne ULg; Lévesque, Benoît

Conference (2008, September 24)

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See detailUne institution en quête de légitimité : le contrat stratégique pour l'Ecole en Communauté française de Belgique
Guillaume, Jean-François ULg

Conference (2008, September 24)

Cette intervention visait à interroger les difficultés existantes dans l'école secondaire de la Communauté française de Belgique et susceptibles d'entraver la mise en oeuvre du programme éducatif affirmé ... [more ▼]

Cette intervention visait à interroger les difficultés existantes dans l'école secondaire de la Communauté française de Belgique et susceptibles d'entraver la mise en oeuvre du programme éducatif affirmé dans le Contrat stratégique pour l'Ecole. [less ▲]

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See detailÉvaluation de 16 mutants du CD18 bovin en vue d’identifier le motif moléculaire responsable de la spécificité d’espèces de Mannheimia haemolytica envers les ruminants
Zecchinon, Laurent; Fett, Thomas ULg; Vanden bergh, Philippe et al

Conference (2008, September 23)

La mannheimiose est la maladie respiratoire prédominante parmi les ruminants alors qu’elle n’affecte pas les autres mammifères. Elle trouve son origine dans l’interaction spécifique entre la leucotoxine ... [more ▼]

La mannheimiose est la maladie respiratoire prédominante parmi les ruminants alors qu’elle n’affecte pas les autres mammifères. Elle trouve son origine dans l’interaction spécifique entre la leucotoxine (LktA) de Mannheimia hæmolytica et la sous-unité CD18 des récepteurs LFA-1 (CD11a/CD18) et Mac-1 (CD11b/CD18) des ruminants. La comparaison des séquences des CD18 de ces derniers et des non-ruminants nous a préalablement permis de mettre en évidence 16 sites qui pouvaient être tenus pour responsables de la spécificité d’espèces de M. haemolytica. Nous avons ainsi utilisé la lignée lymphoblastique humaine K-562, naturellement déficientes en bêta2-intégrines et donc insensibles à la LktA, pour la transfecter de manière transitoire avec les ADNcs codant pour le CD11a bovin et soit le CD18 bovin original, soit une version de celui-ci muté à une des positions d’intérêt, pour obtenir 17 lignées cellulaires différentes. Une analyse par cytométrie en flux a révélé l’expression en surface du LFA-1 bovin natif et de 15 des 16 mutants. Toutes les lignées (sauf celle n’exprimant pas son LFA-1 muté) ont présenté une sensibilité à la cytolyse induite par la LktA et ce, de manière dose-dépendante. Pris dans leur ensemble, ces résultats suggèrent que si certains des sites relevés précédemment jouent un rôle-clé dans la susceptibilité à la LktA de Mannheimia haemolytica, ils ne le font pas à titre individuel. [less ▲]

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See detailThe Io Footprint Morphology
Jacobsen, Sven; Saur, Joachim; Neubauer, F. M. et al

Conference (2008, September 23)

The innermost Galilean moon Io is embedded in a dense plasma torus. It disturbs the flow of the corotating torus plasma and generates MHD waves. Especially the Alfv ́ n e mode, which carries electric ... [more ▼]

The innermost Galilean moon Io is embedded in a dense plasma torus. It disturbs the flow of the corotating torus plasma and generates MHD waves. Especially the Alfv ́ n e mode, which carries electric currents along the magnetic field, is responsible for the famous Io footprint in the Jo- vian aurora. The Alfv ́ n waves are partly reflected at plasma e density gradients e.g. at the torus edges and form a compli- cated wave pattern. The footprint morphology in the Jovian aurora displays this pattern. Besides the main spot feature, a trailing wake extending over up to 100 degrees and occa- sionally occurring multiple spots indicating reflections have been identified. The intensity, the occurrence of multiple spots and the inter-spot distances have been found to vary strongly [1]. Io is moving up and down in the plasma torus confined to the centrifugal equator. It interacts with a dense plasma when located in the torus center and considerably thinner plasma at the torus flanks. The incoming plasma density controls the interaction strength and wave amplitude. This primar- ily leads to a relationship between the footprint brightness and Io’s centrifugal latitude [1]. However, it has also been shown that the reflection angle is strongly depending on the wave amplitude due to nonlinear effects [2]. This has an impact on the inter-spot distances. On the other hand this parameter is also directly affected when Io changes its posi- tion in the plasma torus. To deconvolve this system we present the results of our 3D MHD simulations showing the influence of Io’s centrifugal latitude and nonlinearities on the footprint morphology par- ticularly on the number of spots and inter-spot distances. We observe interference phenomena leading to locally en- hanced or reduced footprint brightness. We also discuss the recently observed leading spot feature [3]. [less ▲]

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See detailThree-dimensional extension of the Io UV footprint emissions
Bonfond, Bertrand ULg; Grodent, Denis ULg; Gérard, Jean-Claude ULg et al

Conference (2008, September 23)

The Io UV footprint is an auroral feature observed close to the feet of the field lines passing through Io on both Jovian hemispheres. These light emissions are caused by the electromagnetic interaction ... [more ▼]

The Io UV footprint is an auroral feature observed close to the feet of the field lines passing through Io on both Jovian hemispheres. These light emissions are caused by the electromagnetic interaction between the satellite Io and the Jovian magnetosphere. For both the north and south poles, the Io footprint appears as a bright spot followed by a faint trailing tail and occasionally followed or preceded by secondary spots. The footprint morphology and the spots multiplicity have been found to vary with the location of Io in the plasma torus. [less ▲]

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See detailThe altitude of Saturn’s aurora: implications for the auroral electron energy and location of the polar homopause
Gérard, Jean-Claude ULg; Bonfond, Bertrand ULg; Gustin, Jacques ULg et al

Conference (2008, September 23)

The Space Telescope Imaging Spectrograph (STIS) and the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST) have been used to study the characteristics of Saturn’s FUV aurora ... [more ▼]

The Space Telescope Imaging Spectrograph (STIS) and the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST) have been used to study the characteristics of Saturn’s FUV aurora, which is dominated by the Lyman and Werner bands of H2 and the H Lyman-α line. Images have been analyzed to determine the altitude of the emission above the limb and infer the characteristic energy of the auroral electrons. Our study shows that the peak of the emission is located 1000-1300 km above the limb, indicating that the precipitated electrons are mostly in the 0.1-1 keV energy range, that is significantly less than on Jupiter. Another source of information on the electron energy are the FUV spectra obtained with Voyager UVS (Sandel et al., 1982) and the HST-STIS (Gérard et al., 2004) and Cassini-UVIS spectrographs which only occasionally show a signature of absorption by hydrocarbons. Consequently, the emission is located above but close to the methane homopause. Finally, EUV spectra collected with the FUSE satellite (Gustin et al., 2008) provide information on the H2 column overlying the aurora through analysis of self-absorption and rotational temperature of the emitting layer from the intensity distribution among the H2 lines. If Moses et al. (2000)’s low latitude model is used to convert altitudes into pressure levels, H2 and hydrocarbon columns and temperature, discrepancies appear between the observed temperature, ultraviolet colour ratio and geometric altitude of the emission. One possibility is that the temperature near the homopause sharply increases at a pressure level higher than in the equatorial regions. [less ▲]

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See detailLa cytolyse des leucocytes caprins induite par la leucotoxine de Mannheimia haemolytica est mediée par la sous-unité CD18 des bêta2-intégrines
Fett, Thomas ULg; Zecchinon, Laurent; Vanden bergh, Philippe et al

Conference (2008, September 23)

La mannheimiose est la maladie respiratoire prédominante parmi les ruminants alors qu’elle n’affecte pas les autres mammifères. Cette spécificité d’espèces trouve son origine dans l’interaction tout aussi ... [more ▼]

La mannheimiose est la maladie respiratoire prédominante parmi les ruminants alors qu’elle n’affecte pas les autres mammifères. Cette spécificité d’espèces trouve son origine dans l’interaction tout aussi spécifique entre la leucotoxine (LktA) de Mannheimia haemolytica et la sous-unité CD18 du récepteur LFA-1 des bêtes bovine et ovine. Nous avons ainsi postulé que la LktA utilisait également le CD18 comme récepteur sur les leucocytes caprins. Pour démontrer cette hypothèse, nous avons transfecté la lignée lymphoblastique K-562, naturellement déficiente en bêta2-intégrines, avec les ADNcs encodant les CD11a et CD18 caprins afin de déterminer la susceptibilité des transfectants à la cytolyse induite par la LktA. Une analyse par cytométrie en flux a révélé l’expression en surface du LFA-1 caprin et la lyse par la LktA de manière dose-dépendante alors que la lignée parentale restait insensible. Par ailleurs, les cellules K-562 exprimant le CD18 caprin et le CD11a humain ou bovin sont également sensibles à la LktA alors que les K-562 exprimant le CD11a caprin et le CD18 humain ne le sont pas. Pris dans leur ensemble, ces résultats indiquent que le CD18 des leucocytes caprins sert de récepteur à la LktA de Mannheimia haemolytica. [less ▲]

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See detailJupiter’s main auroral emission; local time and temporal variability
Grodent, Denis ULg; Radioti, Aikaterini ULg; Bonfond, Bertrand ULg et al

Conference (2008, September 23)

Jupiter's main auroral oval is associated with the ionosphere-magnetosphere coupling current system which is related to the breakdown of corotation in the middle magnetosphere. Its auroral footpath is ... [more ▼]

Jupiter's main auroral oval is associated with the ionosphere-magnetosphere coupling current system which is related to the breakdown of corotation in the middle magnetosphere. Its auroral footpath is usually represented as a smooth line closing around the pole. However, this simplistic view is misleading in many regards. We have constructed a new reference contour in the northern hemisphere (Figure 1), based on more than 1000 HST/UV images, which does not look like an oval and does not close around the pole. We use this reference contour to quantify the effects of temporal and local time variability of the magnetospheric plasma characteristics on the location of the main auroral emission. Beyond the orbit of Ganymede (15RJ), two key ingredients are expected to have a measurable influence on the instantaneous shape of the main emission contour: the azimuthal current flowing in the current sheet [1,2] and the corotation breakdown distance. The former affects the radial extent of the magnetic field lines, and the latter determines the radial location of the field aligned currents transmitting momentum from the planet to the lagging plasma. So far, models used to magnetically map the auroral main emission between the ionosphere and the equatorial plane assumed that these two parameters are constant and axisymmetric. However, in situ observations, mainly by Galileo, have revealed large local time asymmetries and temporal variations in the plasma flows and distribution. These variations have an impact on the azimuthal current and the distance at which the plasma angular velocity becomes significantly smaller than planetary rotation. We use a new magnetic field model [3], inherited from VIP4 and including a magnetic anomaly in the northern hemisphere, to simulate the effects of these asymmetries on the location of the main auroral emission, and interpret the large scattering of the corresponding HST data point. [less ▲]

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See detailDealing with nanotechnology: Do the boundaries matter?
Brunet, Sébastien ULg; Delvenne, Pierre ULg; Fallon, Catherine ULg et al

in Martorell, S.; Guedes Soares, C.; Barnett, J. (Eds.) Safety, Reliability and Risk Analysis: Theory and Applications (2008, September 23)

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See detailEstudio Comparativo de la asociación entre variantes genotípicas del Virus de la Leucemia Bovina y la forma clínica de la infección
Rodriguez, Sabrina ULg; Trono, K.; Jones, L.R.

Poster (2008, September 22)

Estudio Comparativo de la asociación entre variantes genotípicas del Virus de la Leucemia Bovina y la forma clínica de la infección. Sabrina M. Rodríguez1*, Karina Trono1, Leandro R. Jones1,2. 1 Instituto ... [more ▼]

Estudio Comparativo de la asociación entre variantes genotípicas del Virus de la Leucemia Bovina y la forma clínica de la infección. Sabrina M. Rodríguez1*, Karina Trono1, Leandro R. Jones1,2. 1 Instituto de Virología, CICVyA, INTA-Castelar. C.C. 77. C.P. 1712. Castelar, Buenos Aires, Argentina. 2 Dirección actual: Estación de Fotobiología Playa Unión. C.C. 15. C.P. 9103. Rawson, Chubut, Argentina. *E-mail: srodriguez@cnia.inta.gov.ar Introducción. El Virus de la Leucemia Bovina (BLV) es un retrovirus oncogénico que infecta bovinos y es el agente causal de la Leucosis Bovina Enzoótica. El resultado de la infección por BLV es diverso. La mayoría de los individuos infectados (70%) resultan portadores asintomáticos o aleucémicos (AL) y cerca del 25% desarrolla una condición benigna denominada Linfocitosis Persistente (LP). La forma tumoral o linfosarcoma (LS), afecta a un 1-5% de los bovinos infectados que desarrollan una neoplasia B- linfoproliferativa. Las bases genético-moleculares del desarrollo de estas variadas presentaciones clínicas de la infección por BLV son hasta el momento desconocidas. Las secuencias provirales de Repeticiones Terminales Largas (Long Terminal Repeats, LTR) de los retrovirus han sido implicadas en la determinación del tropismo, la virulencia y la patogenicidad, jugando, además, un rol importante en la oncogénesis. Sin embargo, la influencia de la variación genética en las regiones LTR sobre aspectos clínicos de la infección por BLV no ha sido todavía estudiada. Los objetivos de este trabajo fueron caracterizar estas regiones regulatorias y analizar la posible asociación entre las variaciones genéticas del LTR de BLV y las formas clínicas de la infección (AL, PL, LS). Materiales y Métodos. Se amplificó y secuenció la región LTR de 40 provirus obtenidos a partir de bovinos naturalmente infectados por BLV que presentaron las diferentes formas clínicas de la infección. La relación entre caracteres genotípicos y fenotípicos para cada posición variable del LTR fue evaluada mediante métodos comparativos filogenéticos. Para ello se utilizó una filogenia obtenida a partir de secuencias de la región env. La reconstrucción de caracteres en árboles-espejo se llevó a cabo mediante el programa Mesquite y el posterior análisis estadístico de los datos fue realizado mediante el Test Exacto de Fisher. Asimismo, se empleó el Test de Correlación de Pagel implementado en el programa BayesTraits-Discrete para estudiar la existencia de correlación en un marco estadístico-filogenético. Resultados. El análisis de las secuencias de los LTRs reveló la presencia de 7 posiciones polimórficas que podrían variar correlacionadamente con las presentaciones clínicas de la infección (AL/LP y LS). Es decir que la presencia de ciertas bases en determinadas posiciones del LTR podría asociarse con la correspondiente manifestación patogénica asociada a la infección. Los análisis basados en árboles-espejo indicaron que en las posiciones 41 y 56 del LTR dicha asociación es estadísticamente significativa (p<0.05, test Exacto de Fisher). El análisis de Máxima Verosimilitud (modo ML del programa Bayes Traits Discrete) indicó que, para las 7 posiciones analizadas, los datos se ajustan mejor a un modelo en el cual la forma clínica se correlaciona con la genética viral. Resultados similares se observaron mediante la utilización de simulaciones de Monte Carlo (modo MCMC del programa Bayes Traits Discrete): en todas las posiciones los datos se ajustan mejor al modelo dependiente o de correlación (LR > 0). Sin embargo, los valores de LR para todas las posiciones estudiadas no son concluyentes, ya que los valores de LR fueron menores que 2. Conclusión. Los resultados reportados en este trabajo sugieren que al menos dos posiciones de la región LTR (41 y 56) podrían estar implicadas en la determinación de la evolución clínica de los animales infectados por BLV. Estos hallazgos podrían contribuir al conocimiento respecto de las bases moleculares de la patogénesis para este virus. [less ▲]

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See detailEuropean legislation on methods for antibiotics detection in milk
Scippo, Marie-Louise ULg

Conference (2008, September 22)

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See detailLa bêta2-intégrine LFA-1 est le récepteur de la toxine ApxIIIA d’Actinobacillus pleuropneumoniae sur les leucocytes porcins
Vanden bergh, Philippe; Zecchinon, Laurent; Fett, Thomas ULg et al

Conference (2008, September 22)

Actinobacillus pleuropneumoniae, l’agent étiologique de la pleuropneumonie porcine, produit des toxines dites « RTX » (ApxIA, -IIA, -IIIA et -IVA) reconnues comme facteurs de virulence majeurs. Les cibles ... [more ▼]

Actinobacillus pleuropneumoniae, l’agent étiologique de la pleuropneumonie porcine, produit des toxines dites « RTX » (ApxIA, -IIA, -IIIA et -IVA) reconnues comme facteurs de virulence majeurs. Les cibles moléculaires de la liaison de ces toxines sur les cellules porcines n’ont pas été identifiées. Toutefois, il a été démontré que la virulence d’Aggregatibacter actinomycetemcomitans, de Mannheimia haemolytica et de souches pathogènes d’Escherichia coli est associée à l’interaction de leur toxine RTX respective (LtxA, LktA et HlyA) avec le récepteur β2-intégrine CD11a(αL)/CD18(β2) (LFA-1) des leucocytes. Le résultat de cette liaison est une nécrose cellulaire libérant des cytokines et des agents chimiotactiques qui exacerbent l’inflammation et créent un afflux supplémentaire de leucocytes, ce qui génère un cercle vicieux dont on pense qu’il constitue le processus central de la pathogenèse. Comme les toxines Apx sont, moléculairement parlant, très similaires aux toxines précitées, et en raison du fait que les lésions tissulaires qu’elles induisent ressemblent aux lésions causées par les bactéries précitées, nous avons émis l’hypothèse que la pathogenèse de la pleuropneumonie à A. pleuropneumoniae pourrait également dépendre de l’interaction des toxines Apx avec le récepteur LFA-1 porcin (PoLFA-1). Dans ce contexte, nous avons transfecté la lignée lymphoïde humaine K562, réputée ne pas exprimer de β2-intégrines et totalement insensible à la toxine ApxIIIA, avec des plasmides codant les sous-unités PoCD11a et PoCD18. En procédant de la sorte, nous sommes parvenus à rendre cette lignée dûment sensible à la toxine ApxIIIA et en avons conclu que le PoLFA-1 est bien le récepteur enrôlé dans l’interaction cytopathogène. [less ▲]

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See detailDinámica de la infección perinatal con Virus de la Leucosis Bovina en el rodeo lechero
Rossich, G.; Gutiérrez, G.; Rodriguez, Sabrina ULg et al

Poster (2008, September 22)

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See detailNovel pH responsive-copolymers for smart drug carriers
Jérôme, Christine ULg

Conference (2008, September 22)

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See detailCharacteristics and efficiency of some livestock production systems in the Red River Delta: Case study in Cam Giang district, Hai Duong province
Han Quang, Hanh ULg

in Proceedings of the 13th Animal Science Congress of the Asian-Australasian Association of Animal Production Societies (2008, September 22)

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See detailDiversidad genética del Virus de la Leucemia Bovina: una aproximación filogenética
Rodriguez, Sabrina ULg; Trono, K.; Jones, L.R.

Poster (2008, September 22)

Diversidad genética del Virus de la Leucemia Bovina: una aproximación filogenética Sabrina M. Rodríguez1, Karina Trono1, Leandro R. Jones2 1 Instituto de Virología, CICVyA, INTA-Castelar. C.C. 77. C.P ... [more ▼]

Diversidad genética del Virus de la Leucemia Bovina: una aproximación filogenética Sabrina M. Rodríguez1, Karina Trono1, Leandro R. Jones2 1 Instituto de Virología, CICVyA, INTA-Castelar. C.C. 77. C.P. 1712. Castelar, Buenos Aires, Argentina. 2 Estación de Fotobiología Playa Unión. C.C. 15. C.P. 9103. Rawson, Chubut, Argentina. *E-mail: srodriguez@cnia.inta.gov.ar El virus de la leucemia bovina (BLV), agente etiológico de la Leucemia Bovina Enzoótica (LBE), pertenece al género Deltaretrovirus, dentro de la familia Retroviridae. En Argentina, la infección por BLV presenta niveles de seroprevalencia individual del 32,8% y del 84% a nivel predial. En trabajos anteriores, las cepas de BLV han sido clasificadas en dos grupos: uno Europeo y otro que incluye cepas de Japón y Estados Unidos (USA). En dos trabajos mas recientes se observo que la mayoría de las cepas argentinas se agrupan en un clado, mientras que una proporción minoritaria se agrupa con cepas de diverso origen. En uno de estos trabajos se propuso la existencia de cuatro genogrupos (Clusters I a IV), uno de los cuales (Cluster II) seria exclusivo de Argentina. Estas clasificaciones fueron propuestas en base a análisis realizados a partir de matrices de distancias obtenidas a partir de secuencias parciales (444/1547 pb.) del gen env. Las distancias fueron calculadas asumiendo el modelo evolutivo de Kimura con dos parámetros (K2P) y los árboles se obtuvieron mediante el algoritmo Neighbor-Joining (NJ). Actualmente, existen métodos específicos y objetivos para la selección de modelos evolutivos. Se ha demostrado que el uso de modelos arbitrarios puede conducir a resultados inesperados y erróneos. Por otro lado, el algoritmo NJ ha sido ampliamente superado por métodos más exhaustivos y modernos cómo Parsimonia y Máxima Verosimilitud. En este trabajo se caracterizaron 28 provirus argentinos mediante la secuenciación del gen env (1333/1547 pb.). Estas secuencias, junto con otras 42 secuencias seleccionadas de forma tal de abarcar toda la diversidad conocida y de incluir representantes de la mayor cantidad posible de locaciones geográficas, fueron analizadas mediante Parsimonia con el objeto de examinar las clasificaciones previas. Como outgroup (OG), se utilizaron secuencias homólogas de HTLV-1, HTLV-2, STLV-1 y STLV-2. Las secuencias fueron alineadas usando el programa Muscle 3.6. Los alineamientos fueron analizados con el programa TNT 1.1, mediante el cual se realizaron 1000 adiciones al azar (RAS) seguidas de Tree Bisection Reconection (TBR). La estimación del soporte de los grupos identificados se realizó mediante Symetric Jackniffing, utilizando el programa TNT. Nuestros resultados soportan la existencia del clado de secuencias de Japón y USA. Los árboles obtenidos en este trabajo no apoyan ni contradicen el grupo europeo, ya que el mismo podría estar presente en algunas de las posibles resoluciones del árbol sin raíz. Las secuencias de Argentina no se ubicaron en un único grupo sino que se mezclaron con cepas de diverso origen. Nuestros resultados no soportaron la hipótesis de que exista regionalización de las cepas de BLV, tal como se ha observado en HTLV. El árbol consenso de los árboles derivados del análisis incluyendo el outgroup, presentó una resolución relativamente baja con respecto al árbol consenso derivado del análisis sin raíz. Esto parece deberse a que las secuencias utilizadas como outgroup son extremadamente divergentes con respecto al ingroup, lo cual queda en evidencia luego de una simple inspección visual del correspondiente alineamiento. El resultado de esto es que muchas regiones de la matriz constituyen alineamientos al azar (es decir asignaciones de homología primaria incorrectas y aleatorias), con la consecuente pérdida de información. Esta última observación es de particular interés dado que HTLV y STLV han sido utilizados como OG en una gran cantidad de trabajos, lo cual está justificado ya que son los grupos conocidos más próximos a BLV. Nuestros análisis, sin embargo, sugieren fuertemente que es necesario identificar outgroups más adecuados para lograr una comprensión más acabada de la diversidad de estos virus. [less ▲]

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See detailDinámica de la excreción natural del Virus de la Leucosis Bovina en semen de toros infectados naturalmente
Rossich, L.; Gutiérrez, G.; Rodriguez, Sabrina ULg et al

Poster (2008, September 22)

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See detailEstandarización de un ensayo de PCR en tiempo real para la detección y cuantificación del Virus de la Leucosis Bovina en sangre y semen de toros seropositivos
Rossich, L.; González, F.; Gutiérrez, G. et al

Poster (2008, September 21)

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See detailFootball and political violence
Fincoeur, Bertrand ULg

Conference (2008, September 20)

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See detailLa pré-dialyse
Krzesinski, Jean-Marie ULg

Conference (2008, September 19)

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See detailQu’est-ce que les logiciels libres ?
Lejeune, Christophe ULg

Conference (2008, September 19)

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See detailAnalyse collaborative avec Cassandre
Lejeune, Christophe ULg

Conference (2008, September 19)

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See detailApplications de la micro - PIV dans des écoulements libre et confiné
Vetrano, Maria-Rosaria; Ruwet, Vincent; Lebeau, Frédéric ULg et al

Conference (2008, September 16)

L’objectif de cette communication est l’étude de deux micro-écoulements différents au moyen d’un système de micro-PIV non inversé. Ces écoulements diffèrent entre eux par les aspects suivants: Le premier ... [more ▼]

L’objectif de cette communication est l’étude de deux micro-écoulements différents au moyen d’un système de micro-PIV non inversé. Ces écoulements diffèrent entre eux par les aspects suivants: Le premier, un écoulement pulmonaire, est représentatif d’un flux stationnaire confiné. Le second, la formation de gouttelettes par un capillaire contrôlé par un cristal piézoélectrique, est représentatif d’un écoulement périodique à surface libre. La faisabilité de ce type de mesure est évaluée en mettant l’accent sur le fait que ces expérimentations ont été menées sur des micro-écoulements courbes tridimensionnels. [less ▲]

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See detailEquine frozen semen parameters in relation with total myeloperoxidase concentration
Ponthier, Jérôme ULg; Franck, Thierry ULg; Mottart, Evelyne et al

in Animal Reproduction Science (2008, September 15)

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See detailProbing sub-molecular motion in a bistable molecular shuttle
Lussis, Perrine ULg; Bertocco, Andrea; Fustin, Charles-André et al

Poster (2008, September 15)

In recent years it has been proved possible to design synthetic molecular systems in which positional displacements of sub-molecular components occur upon the application of external stimuli.[1-4] Through ... [more ▼]

In recent years it has been proved possible to design synthetic molecular systems in which positional displacements of sub-molecular components occur upon the application of external stimuli.[1-4] Through the pioneering work of Stoddart, Sauvage and others[1-3] it has become clear that the remarkable ability of rotaxanes to change the relative positions of their interlocked components in response to various external stimuli (light, electrons, heat, pH, nature of the environment) should one day find practical uses. However, truly functional systems based on synthetic molecular machines are still to be produced. Some key questions remain unanswered: What are the structural features necessary for molecules to convert this controlled motion into useful function? At what level (single molecule, nanoscopic, microscopic, macroscopic) can this be done? Can we address and utilize the induced-motion in a single molecular machine? To answer those questions we are advocating the use of molecular machines coupled to a polymeric scaffold. We are convinced that this is an efficient route to translate the sub-molecular motion into a useful response that can be exploited to perform physical tasks. Molecular machines with mechanically interlocked architectures are particularly suited for these sorts of applications because, they permit the controlled, large amplitude, movement and positioning of one mechanically interlocked component with respect to another. Among these architectures, rotaxanes -i.e. molecules consisting of a macrocycle threaded on a linear molecule capped with bulky end stoppers- are a particularly promising kind of synthetic molecular 'shuttles'. Our objective is to demonstrate the feasibility of transducing the controlled translational motion of the ring in a rotaxane into mechanical work using AFM-based single molecule force spectroscopy as a mechanical device.[5] For that purpose, a bistable hydrogen-bonded rotaxane with one fumaramide and one succinic amide ester station was synthesized. The equilibrium distribution of the ring between the two stations is in favour of the fumaramide station (>95%).[6] We have attached a poly-ethylene oxide (PEO) chain to the ring by 'click chemistry' and the resulting rotaxane-polymer compound was grafted onto gold substrates. We then fished the PEO chain with an AFM tip. The applied force exerted on the ring when pulling on the polymer chain causes the H bonds linking the ring to the fumaramide station to break, but when trying to move away the ring, it shuttles back to its station in the opposite direction of the pulling force. We estimated that the work done by the ring against the pulling force was about 3 kcal mole-1. This result is in good agreement with the theoretical value predicted by Altieri et. al.[6] [1] Special Issue on Molecular Machines, Acc. Chem. Res. 2001, 34, p. 409-522. [2] V. Balzani, A. Credi, M. Venturi, Molecular Devices and Machines – A Journey into the Nano World, Wiley-VCH, Weinheim, Germany, 2003. [3] E R Kay, D A Leigh and F Zerbetto, Angew. Chem. Int. Ed. 2007, 46, 72. [4] a) V Bermudez, N Capron, T Gase, F G Gatti, F Kajzar, D A Leigh, F Zerbetto and S Zhang, Nature, 2000, 406, 608. b) A M Brouwer, C Frochot, F G Gatti, D A Leigh, L Mottier, F Paolucci, S Roffia, G W H Wurpel, Science , 2001, 291, 2124. c) D A Leigh, J K Y Wong, F Dehez and F Zerbetto, Nature, 2003, 424, 174. d) J V Hernandez, E R Kay and D A Leigh, Science, 2004, 306, 153. e) E R Kay and D A Leigh, Nature, 2006, 440, 286. f) V Serreli, C-F Lee, E R Kay and D A Leigh, Nature, 2007, 445, 523. [5] T. Hugel, N. B. Holland, A. Cattani, L. Moroder, M. Seitz, H. E. Gaub, Science 2002, 296, 1103. [6] A. Altieri, G. Bottari, F. Dehez, D A Leigh, J.K.Y Wong, F Zerbetto, Angew. Chem. Int. Ed. 2003, 42, 2296. [less ▲]

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See detailAFM and Related Techniques: From Imaging to Atomic and Molecular Manipulation
Duwez, Anne-Sophie ULg

Conference (2008, September 14)

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See detailFunctionalized plasmonic gold nanoparticles for optoacoustic cancer detection
Schol, Daureen ULg; Fleron, Maximilien ULg; Greisch, Jean-François et al

Poster (2008, September 12)

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See detailDIETRO L’IMMAGINE RIFLESSA DI UN’ADOLESCENTE.
Miscioscia, Marina ULg; Vaccaro, Maria Grazia; Zanini, Isabella

Poster (2008, September 12)

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See detailExperimental and numerical investigations on iron columns reinforced by FRP under axial compression
Ly, Dong Phuong Lam ULg; Jaspart, Jean-Pierre ULg; Demonceau, Jean-François ULg et al

in Camelbeeck, Th.; Degée, Hervé; Degrande, G. (Eds.) et al Seismic risk (2008, September 11)

This paper presents experimental and numerical investigations on iron columns under axial compression, strengthened with high modulus carbon fibre reinforced polymer (FRP) sheets. It is shown that the ... [more ▼]

This paper presents experimental and numerical investigations on iron columns under axial compression, strengthened with high modulus carbon fibre reinforced polymer (FRP) sheets. It is shown that the resistance and stiffness of iron columns can be increased significantly with the use of longitudinal FRP sheets as a result of the reduction of the column slenderness, but also that transverse FRP sheets should be used to prevent any local buckling of the longitudinal FRP sheets. [less ▲]

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See detailVariétés: orge de brasserie
Monfort, Bruno; Bodson, Bernard ULg

in Livre Blanc: Céréales - Gembloux - Informations avant les semis (2008, September 11)

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See detailDifferent concepts of animal welfare and stakeholders arguments
Bartiaux-Thill, Nicole; Stassart, Pierre M ULg; Lamine, Claire et al

Poster (2008, September 11)

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See detailThe T-cell population in lesions of polyneuritis equi
Van Galen, Gaby ULg; Amory, Hélène ULg; Cehak, Anja et al

in In Proceedings of the 45th Annual Congress of the British Equine Veterinary Association (2008, September 11)

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See detailImagination et politique chez Hobbes
Herla, Anne ULg

Conference (2008, September 11)

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See detailRecent advances in the synthesis of aliphatic polyesters by “click” chemistry
Riva, Raphaël ULg; Jérôme, Christine ULg; Jérôme, Robert ULg et al

Conference (2008, September 11)

Since the discovery of Sharpless and Meldal, the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is more and more popular in the field of macromolecular engineering owing to its robustness, its ... [more ▼]

Since the discovery of Sharpless and Meldal, the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) is more and more popular in the field of macromolecular engineering owing to its robustness, its high tolerance to a wide range of functional groups without any need of protecting groups and the absence of side-products. This reaction is known to be a very efficient “click” reaction as defined by Sharpless. The chemical modification of aliphatic polyesters remains, at the time being, a very difficult task to achieve because of the very limited number of efficient chemical reactions, which can be implemented in the absence of chain degradation. The main purpose of this contribution is to report on the most recent advances on the use of CuAAC to derivatize aliphatic polyesters (Scheme 1). Interestingly enough, it was recently shown that CuAAC carried out onto aliphatic polyesters attached with either azides or alkynes is very efficient under mild conditions, which limit undesirable degradation. Several functional groups were grafted onto aliphatic polyesters by CuAAC without using any protection/deprotection reactions. The CuAAC is also very efficient to prepare aliphatic polyesters with various architectures as highlighted by the synthesis of graft copolymers, star-shaped copolymers and networks. This “click” chemistry has been combined with other polymerization mechanism such as ATRP in order to extend further the range of available polymers. [less ▲]

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See detailMAIN EXISTING IRRIGATION SYSTEMS IN THE SUB-BASINS OF THE TONLE SAP LAKE OF CAMBODIA
Ly, Sarann ULg; Someth, Paradis

Poster (2008, September 11)

The Tonle Sap Lake and its complex tributaries are the main water body and water courses of Cambodia. The catchment area of the lake is generally divided into twelve major sub-basins. The tributaries of ... [more ▼]

The Tonle Sap Lake and its complex tributaries are the main water body and water courses of Cambodia. The catchment area of the lake is generally divided into twelve major sub-basins. The tributaries of the lake have great potential of water resources for agricultural and industrial development. The river networks and existing irrigation projects are not well surveyed. A survey trip was conducted around the lake. The aim of this trip is to understand the river networks and identify main existing irrigation systems in the sub-basins of the Tonle Sap Lake. In this poster, we are mainly focused on the existing irrigation schemes. The schemes are classified into five categories. (1) “Surface runoff collector”: it is formed by a small dike to collect surface runoff from upstream part. The water collected is used as a supplementary water source for rainy season cultivation and for irrigating a small area of dry season cultivation. (2) “Dam reservoir”: a dam is put in place on a river to store the river runoff during the rainy season and the water stored is supplied to a command area in the dry season. (3) “Indirect diversion”: it is characterized by a diversion structure and a storage reservoir. Water is diverted and stored in the reservoir during the rainy season and used for dry season cultivation. (4) “Direct diversion”: characteristic of this type is similar to that of the indirect diversion, except the river water is diverted directly to irrigated area without storing in a reservoir. (5) “Flood storage”: it is generally developed in the floodplain of the Tonle Sap Lake. A ring dike prevents floodwater from entering the reservoir and rainy season rice is grown inside the dike. After harvesting, the gates on the ring dike are opened to receive floodwater. The water is stored inside the dike for cultivating dry season rice outside the dike. This study found that there are only small-scale irrigation schemes developed around/in the Tonle Sap Lake. The water resources of this lake have not been effectively used. [less ▲]

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See detail4. 2008: Une récolte longue et difficile!
Sinnaeve, Georges; Gofflot, Sébastien; Chandelier, Anne et al

in Livre Blanc: Céréales - Gembloux - Informations avant les semis (2008, September 11)

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See detailAnalyse des curriculums officiels et implantés dans les pays de la Confemen
Lejong, Michèle ULg

Conference (2008, September 10)

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See detailMacromolecular engineering of aliphatic polyesters by ring-opening polymerization
Lecomte, Philippe ULg; Jérôme, Christine ULg; Jérôme, Robert ULg

Conference (2008, September 09)

During the past few years, a steadily increasing attention was paid to the synthesis of biodegradable and biocompatible aliphatic polyesters because of potential applications as biomaterials or as ... [more ▼]

During the past few years, a steadily increasing attention was paid to the synthesis of biodegradable and biocompatible aliphatic polyesters because of potential applications as biomaterials or as environmentally friendly thermoplastics. The first purpose of this work is to show that the modification of these aliphatic polyesters by pendant functional groups is an efficient tool to tailor the main properties, including biodegradation rate, bioadhesion, hydrophilicity, degree of crystallinity. The strategies implemented for the synthesis of aliphatic polyesters bearing pendant functional groups rely on the synthesis of g-substituted e-caprolactones followed by their ring-opening polymerization and on the chemical modification of duly functionalized aliphatic polyesters.The second part of the lecture will be dedicated to some recent examples dealing with the use of functional caprolactones to prepare various architectures such as star-shaped copolymers, graft copolymers, macrocycles and networks. [less ▲]

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See detailAbout the use of PCL/clay nanohybrid masterbatches
Benali, Samira; Brocorens, P.; Olivier, A. et al

Conference (2008, September 09)

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See detailAbout pointwise smoothness of some nondifferentiable functions
Nicolay, Samuel ULg

Conference (2008, September 09)

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See detailFoams of polycaprolactone/MWNT nanocomposites for efficient EMI shielding
Thomassin, Jean-Michel ULg; Pagnoulle, Christophe; Bednarz, Lukasz et al

Conference (2008, September 09)

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See detailAbout the use of PCL/clay nanohybrid masterbatches
Benali, Samira; Brocorens, Patrick; Olivier, Aurore et al

Poster (2008, September 09)

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See detailLa subjectivation des normes comme expérience de l’écart, de Foucault à Canguilhem
Bolmain, Thomas ULg

Conference (2008, September 09)

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See detailFunctional nanoobjects by means of polymers
Van Butsele, Kathy; Aqil, Abdelhafid ULg; Jérôme, Christine ULg

Conference (2008, September 08)

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See detailMesoporous TiO2 thin films for photovoltaic applications
Dewalque, Jennifer ULg; Cloots, Rudi ULg; Mathis, François ULg et al

Poster (2008, September 08)

Thin films of nanocrystalline, mesostructured titanium dioxide are very promising materials to build low cost and efficient photovoltaic devices. TiO2 present a high chemical stability and electronic ... [more ▼]

Thin films of nanocrystalline, mesostructured titanium dioxide are very promising materials to build low cost and efficient photovoltaic devices. TiO2 present a high chemical stability and electronic properties such as photoinduced electronic transfer properties associated with the anatase phase. For many applications, highly porous nanostructured thin films with accessible pores are preferable to dense ones. Indeed, high accessible porosity leads to high surface area increasing the electron transfer area. [less ▲]

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See detailLa prééclampsie - éclampsie
Brichant, Jean-François ULg

Conference (2008, September 08)

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Peer Reviewed
See detailElectrochemical characterization of Pt/carbon xerogel and Pt/carbon aerogel catalysts
Job, Nathalie ULg; Maillard, F.; Marie, J. et al

Poster (2008, September 08)

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See detailL'analgésie péridurale en obstétrique et ses échecs
Brichant, Jean-François ULg

Conference (2008, September 08)

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See detailStudying the chemical activation in carbon xerogels
Zubizarreta, Leire; Arenillas, A.; Pis, J. J. et al

Poster (2008, September 08)

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See detailBiomarqueurs en toxicologie: ADN oxydé et adduits à l'ADN
Pirson, Laurence ULg

Conference (2008, September 05)

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See detailHarmonisation of European Construction Law : Consumers First
Kohl, Benoît ULg

Conference (2008, September 04)

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See detailInfluence des processus attentionnels sur le fonctionnement exécutif lors du vieillissement normal
Collette, Fabienne ULg; Hogge, Michaël

Conference (2008, September 04)

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See detailExploration du réseau cérébral impliqué dans des jugements sur soi chez les personnes jeunes et âgées
Feyers, Dorothée ULg; Collette, Fabienne ULg; D'Argembeau, Arnaud ULg et al

Poster (2008, September 04)

Nous avons récemment observé que le cortex préfrontal ventro-médial (CPFVM) est activé à la fois chez des sujets jeunes et âgés dans une tâche de jugement d’adjectifs nécessitant d’évaluer sa propre ... [more ▼]

Nous avons récemment observé que le cortex préfrontal ventro-médial (CPFVM) est activé à la fois chez des sujets jeunes et âgés dans une tâche de jugement d’adjectifs nécessitant d’évaluer sa propre personnalité par rapport à celle d’un autre dans le contexte d’un prise de perspective à la première (1PP) et à la troisième (3PP) personne (Ruby et al., submitted). Nous avons poursuivi l’analyse de ces données par des analyses de connectivité fonctionnelle afin de déterminer le réseau des régions cérébrales associées à la performance des sujets jeunes et âgés. Les résultats montrent qu’en 1PP, l’activité du CPFVM est associée à celle du gyrus frontal inférieur et du gyrus parahippocampique chez les sujet âgés, mais uniquement à celle du cortex occipital chez les sujets jeunes. En 3PP, une connectivité fonctionnelle existe entre le CPFVM et le gyrus frontal médial, le gyrus frontal inférieur et les régions temporales supérieures chez les sujets âgées ; mais uniquement avec les régions occipitale et pariétale chez les sujets jeunes. Les régions cérébrales associées à l’activité du CPFVM chez les sujets jeunes ont été décrites comme impliquées dans la récupération en mémoire autobiographique ainsi que dans les processus de « mentalizing ». En ce qui concerne les personne âgées, le réseau cérébral découvert est relié à la récupération de souvenirs sémantique et épisodique (gyrus parahippocampique et temporal supérieur) mais aussi à l’attribution d’une valence émotionnelle à l’adjectif (gyrus frontal inférieur) et à la prise de perspective (gyrus frontal médial). Ces résultats indiquent (1) que le CPFVM est connecté à un réseau cérébral plus important chez les personnes âgées que chez les jeunes lors de jugement sur soi ; (2) que les sujets jeunes réalisent la tâche sur base d’informations autobiographiques seulement alors que les personnes âgées recrutent en plus des processus cognitifs de nature plus réflexive. [less ▲]

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See detailCellular composition of bronchial brushings obtained from dogs with experimental chronic bronchitis
Bolognin, M.; Tual, Charlotte ULg; Day, M. J. et al

in 18th ECVIM Meeting - Gent - Belgique - 2-5 septembre 2008 (2008, September 02)

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