References of "Poster"
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See detailConsciousness of memory functioning in Alzheimer’s disease
Jaspar, Mathieu ULg; Feyers, Dorothée ULg; Bastin, Christine ULg et al

Poster (2010, May 28)

Metamemory is a multi-faceted concept which deals with the individual’s knowledge and control of memory functioning. Previous studies that have examined the ability of Alzheimer’s disease (AD) patients to ... [more ▼]

Metamemory is a multi-faceted concept which deals with the individual’s knowledge and control of memory functioning. Previous studies that have examined the ability of Alzheimer’s disease (AD) patients to monitor efficiently their memory processes provided contradictory results. These discrepancies between studies could be the result of two factors: the kind of memory task used (episodic, semantic) and the kind of memory process on which memory monitoring is assessed (encoding, maintenance, retrieval). In the present study, different aspects of memory monitoring in 21 AD patients and 21 healthy elderly participants were explored with two tasks : a semantic memory task assessing the feeling-of-knowing (FOK) accuracy for general knowledge and an episodic memory task assessing judgment-of-learning (JOL) and FOK accuracy for information associated to a specific spatiotemporal encoding context By comparison to healthy participants, AD patients exhibit impaired performance on episodic FOK accuracy but not on semantic FOK accuracy. Moreover, no difference was observed between the two groups on the JOL post-encoding accuracy. These results confirm that not all aspects of memory monitoring are impaired in AD. Indeed, although there exists an impairment of episodic FOK performance, semantic FOK and JOL post-encoding appear preserved. The dissociation between the two FOK performance could be due to recruitment of more automatic processes for metacognitive judgment on general knowledge (semantic FOK) than for metacognitive judgment based on specific recent experience (episodic FOK). Similarly, a global prediction during maintenance (JOL) could be based on more automatic processes than an item-by-item judgment during retrieval. [less ▲]

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See detailFeeling of doing in compulsive checking
Belayachi, Sanaa ULg; Van der Linden, Martial ULg

Poster (2010, May 28)

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See detailWhat is the impact of the sequence structure on implicit learning in children?
Lejeune, Caroline ULg; Schmitz, Xavier ULg; Lempereur, Stéphanie et al

Poster (2010, May 28)

It is generally admitted that implicit learning abilities are efficient early in childhood. However, few studies have explored the impact of the structure of the sequence on children’s performance in ... [more ▼]

It is generally admitted that implicit learning abilities are efficient early in childhood. However, few studies have explored the impact of the structure of the sequence on children’s performance in implicit learning tasks. The current research was intended to examine sequence learning abilities in children by comparing sequences of different structural characteristics. [less ▲]

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See detailThe links between dyslexia and inhibition deficits: do dyslexic children with an inhibition deficit have a specific reading profile?
Verhaegen, Clémence ULg; Schelstraete, Marie-Anne; Noël, Marie-Pascale

Poster (2010, May 28)

The present study focused on the nature of the reading disability of children with both dyslexia and inhibition deficit. Van der Schoot et al. (2000; 2004); Nossent et al. (2005); Nossent and Deroux (2006 ... [more ▼]

The present study focused on the nature of the reading disability of children with both dyslexia and inhibition deficit. Van der Schoot et al. (2000; 2004); Nossent et al. (2005); Nossent and Deroux (2006) showed that these children tended more to guess the words they read because these “guessers” found difficulties in suppressing false candidate words that are activated in the lexicon. To test this account, dyslexic children with and without inhibition deficit were presented a sentence reading task. To evoke guessing, each sentence contained a word or a pseudoword which closely resembled either a valid congruent or incongruent word. Our hypothesis was that dyslexic children with inhibition deficit guessed more the word they read from the sentence context and the global word form than dyslexic children without inhibition deficit. The results showed that both dyslexics with and without inhibition deficit tended more to guess the words than control children without dyslexia and inhibition difficulties. We discussed these results with the fact that most of children with reading difficulties use the sentence context to compensate for poor reading skills. [less ▲]

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See detail18F labelling of Insulin via click chemistry
Paris, Jérôme ULg; Mercier, Frédéric ULg; Thonon, David ULg et al

Poster (2010, May 27)

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See detailImprovement of Physicians’ Patient-Centeredness: An Empirical Evidence of the Benefits of a Communication Skills Training Program
Jonius, Bénédicte ULg

Poster (2010, May 27)

Objectives. No study has yet assessed the benefits of a communication skills training program on patient-centeredness. The purpose of this study is to assess the association between ... [more ▼]

Objectives. No study has yet assessed the benefits of a communication skills training program on patient-centeredness. The purpose of this study is to assess the association between patients’characteristics and physicians’ communication skills before and after a communication skills training program. Methods. Correlations between physicians’ communication skills and patients’ characteristics were categorized as absent or present: the number of present correlations indicates the level of patientcenteredness. Communication skills were assessed during a consultation before and after a communication skills training program. Consultations were audio-recorded and transcripted. Communication skills were rated according to the Cancer Research Campaign Workshop Evaluation Manual. Patients’ characteristics (sociodemographic, physical and psychological) were measured before and after the training program. Results. Sixty-three physicians were included. Before training, physicians’ communication skills were associated with one patients’ sociodemographic characteristic and with one psychological characteristic. After training, physicians’ communication skills were associated with none of the patients’ sociodemographic characteristics and with four psychological characteristics. Conclusions. This study highlights that physicians’ patient-centeredness may be improved through a communication skills training program. After training, physicians are more centered on patients’ psychological characteristics and not on patients’ sociodemographic characteristics anymore. This study underlines the need to design communication skills training which may further improve patient-centeredness. [less ▲]

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See detailMethylmercury and selenium in vitro effects on harbor seal (Phoca vitulina) lymphocytes : a multidisciplinary approach
Dupont, Aurélie ULg; Bouquegneau, Jean-Marie ULg; Das, Krishna ULg et al

Poster (2010, May 26)

Methylmercury (MeHg) bioaccumulates along the food web, leading to the highest levels in tissues of predatory species. It constitutes the predominant form present in the blood of marine mammals. The blood ... [more ▼]

Methylmercury (MeHg) bioaccumulates along the food web, leading to the highest levels in tissues of predatory species. It constitutes the predominant form present in the blood of marine mammals. The blood cells, including the immune cells, are therefore exposed to the toxic properties of that chemical. Nevertheless, selenium (Se) is an essential element absorbed concomitantly to MeHg which seems to modulate this toxicity. The goal of this study is to evaluate the immunotoxicity of MeHg on the harbor seal (Phoca vitulina) T lymphocytes, highly important in the adaptive immune response, and to investigate the modulating effect of Se on that toxicity. In parallel, the concentrations of MeHg, total mercury (T-Hg) and Se are determined in free-ranging harbour seal blood in order to follow their contamination levels. The T lymphocytes were isolated from the whole blood, exposed to various MeHg and Se concentrations and the exposure effects were estimated by functional tests including the evaluation of viability, proliferation, metabolic activity, DNA and protein synthesis, and by morphological analysis by transmission electron microscopy. The mean T-Hg concentration was 172 ± 143 µg/l of whole blood. The T lymphocytes cultures in vitro displayed a decreasing number of viable cells with increasing concentrations of MeHg, and numerous ultrastructural defects. The cells exposed to MeHg notably displayed distortion of the plasmic membrane, nucleus fragmentations, chromatin compaction, swelling mitochondrias and cytoplasmic vacuolisations. Those results highlighted various immunotoxic effects of MeHg, both at the functional and ultrastructural levels. The antagonistic role of Se on MeHg immunotoxicity is discussed. [less ▲]

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See detailTailor-made polymers by cobalt-mediated radical polymerization
Debuigne, Antoine ULg; Hurtgen, Marie ULg; De Winter, Julien et al

Poster (2010, May 25)

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See detailStimuli-responsive triblock copolymer for biomedical applications
Sibret, Pierre ULg; Croisier, Florence ULg; Zhao, J. et al

Poster (2010, May 25)

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See detailLe rôle du vagabondage de l’esprit dans le maintien d’un état anxiété
Stawarczyk, David ULg; Blanchy, Sarah ULg; D'Argembeau, Arnaud ULg

Poster (2010, May 25)

Le vagabondage de l’esprit (c’est-à-dire, l’apparition spontanée de pensées prenant leur origine dans la mémoire à long-terme et sans lien avec la tâche en cours de réalisation) est un phénomène fréquent ... [more ▼]

Le vagabondage de l’esprit (c’est-à-dire, l’apparition spontanée de pensées prenant leur origine dans la mémoire à long-terme et sans lien avec la tâche en cours de réalisation) est un phénomène fréquent qui représente en moyenne 10 à 30% de nos pensées journalières. Les recherches dans le domaine suggèrent que ce type de pensées est lié à la gestion de nos préoccupations actuelles et que sa fréquence peut être augmentée par l’induction d’affects négatifs. Cependant, le rôle possible de ces pensées dans le maintien des affects négatifs est encore mal connu. Dans cette étude, une préoccupation anxiogène (supposément devoir réaliser un discours filmé) ou une préoccupation neutre (supposément devoir réaliser une tâche cognitive de réflexion) a été induite immédiatement avant la réalisation d’une tâche exécutive d’inhibition durant laquelle la fréquence et le contenu des pensées distractives ont été évalués. Trois mesures de l’état émotionnel des participants ont été réalisées : (1) au début de la session, (2) après l’induction de la préoccupation et (3) après la tâche exécutive. Les résultats montrent la présence d’un plus grand nombre de pensées distractives liées à la préoccupation induite, d’un plus grand nombre d’erreurs d’inhibition ainsi que d’une augmentation significative des affects négatifs entre les temps 1 et 2 dans la condition anxiogène par rapport à la condition neutre. Par ailleurs, une corrélation négative entre le nombre de pensées distractives liées au discours et la diminution de l’anxiété entre les temps 2 et 3 est observée. Ces résultats démontrent l’importance des cognitions anticipatoires spontanées dans le maintient de l’anxiété. [less ▲]

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See detailEffects of androgenic and anti-androgenic substances on the freshwater gastropod Lymnaea stagnalis
Giusti, Arnaud ULg; Ducrot, Virginie; Joaquim-Justo, Célia ULg et al

Poster (2010, May 25)

Knowledge on the impacts of endocrine disrupting chemicals (EDCs) on gastropods is scarce and their mechanisms of action are still poorly understood. In this study, effects of 3 androgens (tributyltin ... [more ▼]

Knowledge on the impacts of endocrine disrupting chemicals (EDCs) on gastropods is scarce and their mechanisms of action are still poorly understood. In this study, effects of 3 androgens (tributyltin, testosterone and fenitrothion), 2 anti-androgens (cyproterone acetate and vinclozolin) and 1 estrogen (chlordecone) on growth and reproduction were investigated in the hermaphrodite gastropod Lymnaea stagnalis. [less ▲]

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See detailImpacts of androgenic and antiandrogenic substances on the freshwater pulmonate gastropod Lymnaea stagnalis
Giusti, Arnaud ULg; Lagadic, Laurent; Joaquim-Justo, Célia ULg et al

Poster (2010, May 23)

Knowledge on the impacts of endocrine disruptors on gastropods is scarce and their mechanism of action poorly understood especially the impacts of androgenic and antiandrogenic compounds. In this study ... [more ▼]

Knowledge on the impacts of endocrine disruptors on gastropods is scarce and their mechanism of action poorly understood especially the impacts of androgenic and antiandrogenic compounds. In this study effects of 5 androgenics and antiandrogenics endocrine disruptors were investigated on the reproduction and life traits of the freshwater pulmonate gastropod Lymnaea stagnalis. The chemicals tested were Tributyltin, Cyproterone acetate, Methyltestosterone, Vinclozolin and Fenitrothion. Tributyltin was used as androgenic positive control. The other compounds tested are androgenic and antiandrogenic compounds either steroids or non steroids. Adult snails were exposed to 3 concentrations of each chemical for 30 days. The size and reproductive organs development were monitored throughout exposure. The number of clutches, the number of eggs per clutch were assessed during the first 10 days. The clutches were kept individually in clear water except for the clutches of the eighth day which were divided in two. Half was kept individually in clear water and the other half was individually reared in contaminated water following the same exposure as their parents. The percentage of hatching per clutch of these clutches was measured. The development size, mortality, and development of reproductive organs of the juveniles were assessed until their first clutch was laid. [less ▲]

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See detailRelationship between BET specific surface area, DR- and t-plot pore volume
Scherdel, C.; Reichenauer, G.; Wiener, M. et al

Poster (2010, May 23)

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See detailImpact of anti-androgens on the production of spermatozoa in Brachionus calyciflorus
Joaquim-Justo, Célia ULg; Cruciani, Valentina ULg; BLASZCZYK, Marie ULg et al

Poster (2010, May 23)

Putative endocrine disruptors affect rate of fertilization of sexual females by males. Preston et al. (2000) reported a decrease in fertilization rate following exposition to, notably, flutamide at 10µg/l ... [more ▼]

Putative endocrine disruptors affect rate of fertilization of sexual females by males. Preston et al. (2000) reported a decrease in fertilization rate following exposition to, notably, flutamide at 10µg/l. We observed similar effects with fenitrothion. Cross mating experiments showed that the decrease in fertilization rate is due to an impact on males exclusively. We studied the impact of anti-androgens on spermatogenesis and observed a decrease in the spermatozoa production with concentrations down to 0,5 mg L-1.We also report a detailed description of the morphology of the male reproductive apparatus in B. calyciflorus based on optic and electronic microscopy analysis and we describe the effect of anti-androgens on males and spermatogenesis in males. [less ▲]

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See detailLes enzymes et leur utilisation en biotechnologie industrielle
Galonde, Nadine ULg

Poster (2010, May 22)

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See detailInvolvement of miR-125b in in vitro and in vivo angiogenesis
Malvaux, Ludovic; Pendeville, Hélène; Sabatel, Céline et al

Poster (2010, May 21)

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See detailComplementation of Saccharomyces cerevisiae mutants using a soil metatranscriptomic library
Kellner, Harald ULg; Luis, Patricia; Portetelle, Daniel ULg et al

Poster (2010, May 21)

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See detailmiR-146a: an anti-angiogenic miRNA regulated by NF-kB
Halkein, Julie ULg; Tabruyn, Sébastien ULg; Malvaux, Ludovic et al

Poster (2010, May 21)

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See detail16K human prolactin is an anti-lymphangiogenic factor in vitro and in vivo
Kinet, Virginie; Castermans, Karolien; Blacher, Silvia ULg et al

Poster (2010, May 21)

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See detailEtude du mode de liaison des canaux potassiques de type SK et l’apamine par modélisation moléculaire
Dilly, Sébastien ULg; Lamy, Cédric; Seutin, Vincent ULg et al

Poster (2010, May 20)

Parmi les canaux ioniques impliqués dans le contrôle de l'activité neuronale, les canaux potassiques calcium-dépendants de basse conductance, dénommés canaux SK, constituent une cible thérapeutique ... [more ▼]

Parmi les canaux ioniques impliqués dans le contrôle de l'activité neuronale, les canaux potassiques calcium-dépendants de basse conductance, dénommés canaux SK, constituent une cible thérapeutique intéressante. En effet, ils sous-tendent la posthyperpolarisation ("AfterHyperPolarization") de durée moyenne (mAHP) qui limite l'excitabilité de divers types de neurones du système nerveux central (SNC). A ce jour, 3 types de sous-unités, SK1, SK2 et SK3, ont été identifiés dans différentes régions du cerveau. Le blocage sélectif de ces canaux pourrait être bénéfique dans le traitement de divers troubles du SNC comme la maladie de Parkinson (SK3), la dépression (SK3) ou encore les désordres cognitifs (SK2) (Liégeois et al., 2003 ; Pedarzani et al., 2008). Jusqu’à présent, le site d’interaction entre les canaux SK et leurs bloqueurs n’a pas encore été précisément élucidé. Dans ce contexte, nous avons entrepris la modélisation de ces canaux par homologie comparative en se basant sur la structure cristalline du canal potassique KCSA (Doyle et al., 1998). La construction de ces canaux constitue la première étape dans la détermination des requis structuraux essentiels à l’affinité de bloqueurs et à la compréhension des modes de liaison de ces ligands. Le mode de liaison de l’apamine, bloqueur peptidique issu du venin d’abeille, a été ensuite exploré par « docking ». Afin de confirmer ce site de liaison potentiel, des expériences de mutagénèse dirigée ont été réalisées. Les premiers canaux mutants testés dans des expériences électrophysiologiques par la technique de « patch clamp » ont permis de valider certaines données théoriques. Grâce à cette stratégie, nous espérons préciser le mécanisme d'action des bloqueurs des canaux SK et, idéalement, découvrir des pistes pour concevoir des bloqueurs sélectifs. [less ▲]

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See detailDe la prévention chronologique à la prévention relationnelle; la prévention quaternaire comme tâche du médecin de famille.
Jamoulle, Marc ULg

Poster (2010, May 19)

La prévention clinique est traditionnellement exprimée comme une vue du médecin sur une tâche à réaliser avant la survenue d’un évènement. Initiée par Leavell et Clark en 1958 elle est complétée en 1988 ... [more ▼]

La prévention clinique est traditionnellement exprimée comme une vue du médecin sur une tâche à réaliser avant la survenue d’un évènement. Initiée par Leavell et Clark en 1958 elle est complétée en 1988 par J-A Bury qui dénomme prévention quaternaire les soins palliatifs.Le paradigme change, le patient devient central aux soins, la prévention clinique est perçue au travers de la relation entre le médecin et le patient. Le croisement de la science du médecin et de la conscience du patient permet de répartir la prévention en quatre champs. Elle est traversée en oblique par la ligne du temps. Cette proposition (Jamoulle, 1986) a été avalisée par la Wonca et l’UEMO et permet de cadrer quatre concepts de prévention clinique. [less ▲]

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See detailBiological control using Episyrphus balteatus (De Geer) (Diptera: Syrphidae)
Leroy, Pascal ULg; Verheggen, François ULg; Capella, Quentin et al

Poster (2010, May 18)

Augmentative biocontrol constitutes a safe way to reduce pest populations through the enhancement of natural enemies’ activity. In this context, the aphidophagous syrphid Episyrphus baltetaus (De Geer ... [more ▼]

Augmentative biocontrol constitutes a safe way to reduce pest populations through the enhancement of natural enemies’ activity. In this context, the aphidophagous syrphid Episyrphus baltetaus (De Geer) (Diptera: Syrphidae) is a promising candidate for aphid biological control: larvae of this syrphid attack and consume a wide range of aphid species and are found on many vegetable crops. Because natural populations of beneficials are not always sufficient to regulate the pest infestations, this work has focused on the conception of a biological control device containing syrphid eggs which can easily be introduced in fields or greenhouses. Using semiochemicals [E-(β)-farnesene, R-(+)-limonene and (Z)-3-hexenol], honeydews and “artificial honeydews” (10% or 30% aqueous solutions of sucrose, fructose and glucose), the syrphid oviposition was artificially induced on an inert surface. To test and validate the biological control device described above, laboratory and field experiments were performed: a plastic lamella covered with syrphid eggs was suspended on aphid infested plants in order to measure the efficiency of the device. The results obtained were promising since populations of 500 aphids were eliminated in ten days when 15 syrphid eggs were introduced. The use of such a biological control device could certainly contribute to aphid biological control strategies. [less ▲]

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See detailA Far-UV Imager for the Jupiter Ganymede Orbiter
Bunce, E. J.; Molyneux, P.; Bannister, N. et al

Poster (2010, May 17)

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See detailL'inventaire du bois mort à terre
Ligot, Gauthier ULg; Rondeux, Jacques ULg

Poster (2010, May 12)

Le bois mort à terre est devenu un indicateur reconnu de la biodiversité et de la gestion durable des forêts. Il importe donc de pouvoir apprécier les quantités de mort à l'hectare. Choisir la méthode d ... [more ▼]

Le bois mort à terre est devenu un indicateur reconnu de la biodiversité et de la gestion durable des forêts. Il importe donc de pouvoir apprécier les quantités de mort à l'hectare. Choisir la méthode d'échantillonnage à utiliser reste une tâche ardue bien qu'il existe une abondante littérature sur le sujet. Ce poster compare deux techniques généralement utilisées : les placettes de taille fixe et les transects. Nous avons évalué ces deux méthodes aussi bien à l'échelle locale que nationale et au travers de simulations statistiques nous en avons évalué la précision et l'efficacité. De plus, nous mettons en évidence l'importance d'utiliser des fonctions de conversion des estimations obtenues dans un but d'harmonisation internationale des résultats. [less ▲]

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See detailTypologie des chênaies de la Région wallonne
Perin, Jérôme ULg; Brostaux, Yves ULg; Claessens, Hugues ULg

Poster (2010, May 12)

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See detailL'inventaire forestier national permanent du Grand-Duché de Luxembourg, aide au monitoring de la biodiversité
Alderweireld, Matthieu ULg; Kugener, Georges; Wagner, Marc et al

Poster (2010, May 12)

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See detailAvifaune forestière - Etude d'habitat du Pic mar
Lehaire, François ULg; Paquet, Jean-Yves; Delahaye, Laurence et al

Poster (2010, May 12)

En tant que bio-indicateurs, les espèces spécialistes des grands massifs forestiers feuillus ont un intérêt pour l'étude et le suivi de la diversité de ces milieux.

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See detailL'inventaire forestier national permanent du Grand-Duché de Luxembourg, aperçu de la méthodologie
Alderweireld, Matthieu ULg; Kugener, Georges; Wagner, Marc et al

Poster (2010, May 12)

L'inventaire forestier national du Grand-Duché de Luxembourg assure depuis 1998 la mesure par échantillonnage des 89 000 ha de forêt que compte le pays. La collecte des données s'étale sur 3 ans et est ... [more ▼]

L'inventaire forestier national du Grand-Duché de Luxembourg assure depuis 1998 la mesure par échantillonnage des 89 000 ha de forêt que compte le pays. La collecte des données s'étale sur 3 ans et est réalisée tous les 10 ans au niveau d'unités d'échantillonnage à placettes concentriques. Ces données concernent tous les aspects de la forêt dans l'esprit de multifonctionnalité qui lui est assigné. [less ▲]

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See detailSTEM CELL IN THE TREATMENT OF TENDONITIS IN EQUINE PATIENTS
Verwilghen, Denis ULg; Briquet, Alexandra ULg; Gothot, André ULg et al

Poster (2010, May 07)

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See detailInfluence Des Conditions Extérieures Sur Le Comportement Au Séchage d'un Milieu Poreux
Kahlerras, Loubna ULg; Belhamri, Azeddine

Poster (2010, May 07)

Ce travail se propose d’analyser les phénomènes du séchage convectif d’un milieu poreux non saturé. Le modèle de calcul considère le couplage des équations de la couche limite et celles qui décrivent le ... [more ▼]

Ce travail se propose d’analyser les phénomènes du séchage convectif d’un milieu poreux non saturé. Le modèle de calcul considère le couplage des équations de la couche limite et celles qui décrivent le transfert de chaleur et de masse dans un milieu poreux, ayant les caractéristiques du béton renforcé avec des coupeaux de bois. La simulation effectuée montre l’effet de certains paramètres pertinents du matériau comme la température initiale et l’humidité initiale, sur le processus du séchage [less ▲]

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See detailRisk assessment of soil compaction in Walloon Region (Belgium)
Rosiere, Charlotte ULg; Delvoie, Simon ULg; Charlier, Robert ULg et al

Poster (2010, May 07)

The proposed Soil Framework Directive COM(2006)232 requires Member States to identify areas at risk of erosion, decline in organic matter, salinisation, compaction, sealing and landslides, as well as to ... [more ▼]

The proposed Soil Framework Directive COM(2006)232 requires Member States to identify areas at risk of erosion, decline in organic matter, salinisation, compaction, sealing and landslides, as well as to set up an inventory of contaminated sites. The present project aims to identify the susceptibility to compaction of soils of the Walloon Region (Belgium) and to recommend good farming practices avoiding soil compaction as far as possible. Within this scope, the concept of precompression stress (Pc) (Horn and Fleige, 2003) was used. Pc is defined as the maximum major principal stress that a soil horizon can withstand against any applied external vertical stress. If applied stress is higher than Pc, the soil enters in a plastic state, not easily reversible. For a given soil, the intensity of soil compaction is mainly due to the applied load which depends on vehicle characteristics (axle load, tyre dimensions, tyre inflation pressure, and vehicle velocity). To determine soil precompression stress, pedotransfert functions of Lebert and Horn (1991) defined at two water suctions (pF 1.8 and 2.5) were used. Parameters required by these functions were found within several databases (Aardewerk and Digital Map of Walloon Soils) and literature. The validation of Pc was performed by measuring stress-strain relationships using automatic oedometers. Stresses of 15.6, 31, 3, 62.5, 125, 250, 500 and 1000 kPa were applied for 10 min each. In this study, the compaction due to beet harvesters was considered because the axle load can exceed 10 tons and these machines are often used during wet conditions. The compaction at two depth levels was considered: 30 and 50 cm. Compaction of topsoil was not taken into account because, under conventional tillage, the plough depth is lower than 25 cm. Before and after the passage of the machines, following measurements were performed: granulometry, density, soil moisture, pF curve, Atterberg limits, ... The software Soilflex (Keller et al., 2007) was used to estimate the distribution of the vertical stresses sigma z in the soil. Comparison was performed between sigma z and Pc. The following data simulated the passage of a beet harvester machine (mass: 23 580 kg; load: 18 000 kg) in a silty soil located in Hesbaye and classified as Aba (Sirjacobs et al., 2000). The passage of the machine would create a Pc of around 100 kPa at 30 cm depth, while the stress induced by the machine would reach 240 kPa. In the field borders, where more vehicle traffic was usually observed and where the soil was over consolidated, Pc would reach 180 kPa, while sigma z would be 220 kPa. In both cases, the risk of compaction created by the passage of the machine would be high. [less ▲]

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See detailPaleoproductivity and carbon cycling during the Middle Miocene Monterey Excursion
Billups, Katarina; Diester-Haass, Liselotte; Emeis, Kay-Christian et al

Poster (2010, May 06)

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See detailOn the local operational geomagnetic index K calculation
Stankov, Stan; Stegen, Koen; Wautelet, Gilles ULg et al

Poster (2010, May 06)

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See detailMonitoring a shallow geothermal experiment in a sandy aquifer using electrical resistivity tomography: a feasibility study
Hermans, Thomas ULg; Vandenbohede, Alexander; Nguyen, Frédéric ULg et al

Poster (2010, May 06)

Geothermal resources, especially groundwater resources, are increasingly used around the world. It is therefore necessary to improve the characterisation of thermal parameters of the aquifers. This is ... [more ▼]

Geothermal resources, especially groundwater resources, are increasingly used around the world. It is therefore necessary to improve the characterisation of thermal parameters of the aquifers. This is done mostly with thermal response tests. In this work, we monitored with electrical resistivity tomography a geothermal test on the campus of Ghent University (Belgium). We injected warm water (45°C) into a sandy aquifer where the groundwater has a temperature of 10°C at a rate of 100 liter/hour during three days. Laboratory measurements indicated that we could expect at most a change of 2%/°C of the water electrical conductivity. The time-lapse series of electrical images show clearly the thermal plume corresponding to the injected water with a maximum change of minus 20% after 72 hours of injection. A comparison with a geothermal model shows that the anomaly is well detected but also distorded due to the inversion regularization (smoothness constraint). ERT enabled to follow the evolution of the injected heated water with more spatial coverage that traditionnal techniques. ERT is thus an interesting tool to monitor the exploitation of geothermal resources. In the future, it will be necessary to improve the inversion process to use quantitavely such results in a calibration process. [less ▲]

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See detailOptimisation of slow-release formulations as biological control devices
Heuskin, Stéphanie ULg; Lorge, Stéphanie; Debatty-Mestdagh, Michelle et al

Poster (2010, May 05)

E-β-Farnesene, the alarm pheromone of many aphid species and β-caryophyllene, recently identified as one of the possible component of the aggregation pheromones of the Asian ladybeetles Harmonia axyridis ... [more ▼]

E-β-Farnesene, the alarm pheromone of many aphid species and β-caryophyllene, recently identified as one of the possible component of the aggregation pheromones of the Asian ladybeetles Harmonia axyridis Pallas, are considered as two sesquiterpenes attractive for aphids’ predators and parasitoids, Epysirphus balteatus De Geer and Aphidius ervi Haliday, respectively. In the present research, alginate gel beads formulations were optimised as semiochemical slow-release devices. The formulations were evaluated in terms of volatiles release capacity, protection efficiency of sesquiterpenes against oxidation, and biological activity towards Epysirphus balteatus and Aphidius ervi. Moreover, the sesquiterpenes used in the formulations were obtained from natural matrices. Indeed, they were purified by flash chromatography fractionation of essential oils of Matricaria chamomilla L. and Nepeta cataria L., for obtaining E-β-farnesene and β-caryophyllene, respectively. The purities of the fractions were determined by means of a fast GC analytical method optimised for a good resolution of terpenes in less than five minutes. The experiments can conclude that the alginate gel beads formulations are efficient as biological control devices considering the results obtained with the various biological tests led on predators and parasitoids. Moreover, the sesquiterpenes are more protected when formulated in alginate beads than without formulation. The devices allow also a slow-release of semiochemicals during a long time (at least 40 days) depending on physico-chemical parameters (temperature, relative humidity). A mathematical modelisation of semiochemicals release is presently in study. [less ▲]

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See detailDesign of a decision tool for hydromorphological restoration of water bodies in Walloon Region
Peeters, Alexandre ULg; Hallot, Eric ULg; Verniers, Gisèle et al

Poster (2010, May 05)

The pilot project WALPHY (LIFE + Environment LIFE07 ENV/B/000038, UE-funded) develops a structured approach aiming at improving hydromorphological quality of the upstream Meuse basin in order to achieve ... [more ▼]

The pilot project WALPHY (LIFE + Environment LIFE07 ENV/B/000038, UE-funded) develops a structured approach aiming at improving hydromorphological quality of the upstream Meuse basin in order to achieve the “good ecological status” required by the Water Framework Directive (WFD 2000/60). It began in January 2009 for a period of 5 years. River’s biological recovery needs the recovery of river’s structure and physical dynamics. Returning to "good ecological status" inevitably involves physical restoration of affected rivers. Physical component of aquatic environment acts as a limiting factor for their functioning. Three types of modification are key obstacles for river good ecological status: (i) fluxes alteration (discharge, sedimentation. . . ), (ii) forms alteration (uniform facies. . . ) and (iii) biotopes access alteration (lateral connections breaks, modification of the continuity upstream/ downstream. . . ). Therefore hydromorphology is needed to implement the WFD. To respond to this legal necessity, we develop a unique, useful and suitable methodology in Walloon Region to determine and schedule river physical quality restoration works. This methodology has been applied on 3 “risk water bodies”. The works are based on two axes : longitudinal continuity and transversal continuity. The two first selected water bodies (Bocq river, eastern tributary of the Meuse) seem to be convenient for the restoration works which concern the longitudinal continuity due to the presence of dams and other obstacles usually between 1 and 3 m high. These works consist in dam management (weir removal or fish passage) taking into account hydromorphological (bedload transport) and biological (invertebrate or fish species free movement) impacts. The third water bodies (Eau Blanche river, western tributary of the Meuse) presents straightened rivers with artificial banks, witch consequently own bad connections between the stream and its floodplain. This water bodies should therefore be appropriated for the works based on the transversal continuity recovery. They consist in enhancing straightened river channels, restoring meanders or bank restoration. The first river restoration works will take place from summer 2010. A monitoring has already been undertaken to draw up the situation before the restoration works, witch will be able to compare to the situations during and after works. In addition, a natural site has been chosen to enable any comparison with the intervention sites. The geomorphological monitoring is based on physical and sedimentological parameters (substrate cartography, velocity measures, stream channel DEM, topography and sedimentological index). The ecological monitoring consists in analysing the physical and chemical parameters (turbidity, suspended sediment load). It also analyses the biological quality through 3 indicators: macrophytes, macroinvertebrates and fishes. Among other, a microhabitats method has been improved and applied on 3 intervention sites and 1 natural site. The microhabitats cartography results from both the flow velocity cartography and the substrate cartography. With this method, the physical quality of each intervention site could be compared with the natural site and above all with the future situation. Our method is also useful to inventory precisely invertebrates and to characterise fish habitats. [less ▲]

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See detailEvolution of Harmonia axyridis (Pallas) alkaloid protection during the year
Fischer, Christophe ULg; Sibret, Virginie; Laurent, Pascal ULg et al

Poster (2010, May 05)

Detailed reference viewed: 54 (13 ULg)
See detailBiological control device using the aphidophagous hoverfly Episyrphus balteatus (De Geer) (Diptera: Syrphidae)
Leroy, Pascal ULg; Verheggen, François ULg; Francis, Frédéric ULg et al

Poster (2010, May 05)

Augmentative biocontrol constitutes a safe way to reduce pest populations through the enhancement of natural enemies’ activity. In this context, the aphidophagous syrphid Episyrphus baltetaus (De Geer ... [more ▼]

Augmentative biocontrol constitutes a safe way to reduce pest populations through the enhancement of natural enemies’ activity. In this context, the aphidophagous syrphid Episyrphus baltetaus (De Geer) (Diptera: Syrphidae) is a promising candidate for aphid biological control: larvae of this syrphid attack and consume a wide range of aphid species and are found on many vegetable crops. Because natural populations of beneficials are not always sufficient to regulate the pest infestations, this work has focused on the conception of a biological control device containing syrphid eggs which can easily be introduced in fields or greenhouses. To test and validate the biological control device described above, laboratory and field experiments were performed: a plastic lamella covered with syrphid eggs was suspended on aphid infested plants in order to measure the efficiency of the device. The results obtained were promising since populations of 500 aphids were eliminated in ten days when 15 syrphid eggs were introduced. The use of such a biological control device could certainly contribute to aphid biological control strategies. [less ▲]

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See detailParticularities of Aphidius ervi embryo development and main limitations of its in vitro culture
Sabri, Ahmed ULg; Leroy, Pascal ULg; Hance, Thierry et al

Poster (2010, May 05)

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See detailLong term carbon dioxide exchange above a mixed forest in the Belgian Ardennes: evaluation of different approaches to deduce total ecosystem respiration from Eddy covariance measurements
Jerome, Elisabeth ULg; Heinesch, Bernard ULg; Aubinet, Marc ULg

Poster (2010, May 05)

The general aim of this research is to analyze inter annual variability of carbon dioxide (CO2) fluxes exchanged by a mixed forest located at the Vielsalm experimental site in Belgium. At this site, CO2 ... [more ▼]

The general aim of this research is to analyze inter annual variability of carbon dioxide (CO2) fluxes exchanged by a mixed forest located at the Vielsalm experimental site in Belgium. At this site, CO2 flux measurements started in 1996 and are still going on. Thirteen complete years of measurements are thus available. Net Ecosystem Exchange (NEE) inter annual variability may be driven by gross primary productivity (GPP) or Total Ecosystem Respiration (TER), which should thus be both quantified. Using flux partitioning methods, TER is deduced from NEE measurements. GPP is then obtained by subtracting TER from NEE. Initially, a robust estimation of TER is required. This work seeks to compare two independent approaches to assess TER in order to quantify the implications on inter-annual variability. The comparison was performed on twelve complete years. TER estimates can be deduced by extrapolating to the whole day NEE measurements taken during selected night or day periods. In both case, the extrapolation is performed by using a respiration response to temperature. The first approach, referred as the night-time approach, consisted in calculating TER using a temperature response function derived from night-time data sets (Reichstein et al., 2005). The second approach, referred as the daytime approach, consisted in assessing TER from the intercept of the NEE/Photosynthetically Photon Flux Density (PPFD) response (Wohlfahrt et al., 2005). For each approach, different modalities were compared: the use of long term (annual) or short term (15 days) data sets for the night-time approach and the use of different types of regression for the daytime approach. In addition, the impact of the temperature choice was studied for each of the approaches. For the night-time approach, main results showed that air temperature sensitivity of ecosystem respiration derived from annual data did not reflect the short-term air temperature sensitivity. Vielsalm is a summer active ecosystem (annual temperature sensitivity larger than short-term temperature sensitivity). Results suggested also that, for both approaches, regressions based on soil temperature gave more robust results than those based on air temperature. Furthermore, the comparison showed that the night-time and the daytime approaches give disagreeing pictures of TER inter annual variability which suggested that the choice of the approach is critical in order to correctly depict TER inter annual variability. Finally, at this stage, TER inter annual variability cannot be explained by variability of climatic conditions. [less ▲]

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See detailPheromone variability and evolution in the butterfly genus Bicyclus, and implication in its diversification
Bacquet, Paul; Brattström, O.; Brakefield, P. M. et al

Poster (2010, May 05)

The evolution of olfactive communication in generating reproductive isolation among species remains poorly understood (Smadja & Butlin 2009). In Lepidoptera, studies have mainly focused on long-distance ... [more ▼]

The evolution of olfactive communication in generating reproductive isolation among species remains poorly understood (Smadja & Butlin 2009). In Lepidoptera, studies have mainly focused on long-distance pheromones produced by moths. Moth sex pheromones have been shown to display inter-population variation (e.g. Tòth et al. 1992, McElfresh & Millar 2008 and ref. within, Groot et al. 2009) and to be involved in interspecific isolation (e.g. Löfstedt et al. 1991, Groot et al. 2006). In butterflies, the few existing studies on sex pheromones have mainly focused on the identification of the male specific compounds and the demonstration of their behavioural activity in courtship (e.g. Grula et al. 1980, Nieberding et al. 2008, Yildizhan et al. 2009), but have failed so far to highlight a role in reproductive isolation (Friberg et al. 2008). In the species-rich Bicyclus genus Kirby, 1871 (Nymphalidae, Satyrinae) the structures producing the pheromones, i.e. the androconia, are key characters to discriminate among species (Condamin 1973). In B. anynana (Butler, 1879), the male sex pheromone (MSP) has been shown to play a role in mate choice (Costanzo & Monteiro 2007, Nieberding et al. 2008), to be heritable, and particular ratios of the pheromone components are under strong sexual selection (Nieberding et al, unpubl. data). Therefore, we expect that pheromone evolution is responsible for reproductive isolation and diversification in this butterfly group. In this framework, our research project aims at understanding the evolution of MSP at the interspecific level across the Bicyclus genus and specifically at testing their potential role in the speciation process. Potential MSP of several species across the Bicyclus genus have been identified by gas chromatography and mass spectrometry. Observed differences in pheromone composition between species are compared in a phylogenetic framework to the molecular tree of the species (following Oliver et al. 2009). We expect the evolutionary rate of MSP to be unlinked to the molecular tree if MSP are under sexual selection across the genus (i.e. saltational evolution following Symonds & Elgar 2004, Shirangi et al. 2009). Moreover, if MSP generated reproductive isolation between species in a “reinforcement” process, we expect higher differences of MSP composition between sympatric species than between allopatric species and an increase of this pattern for younger species compared to older species (Lukhtanov et al. 2006). [less ▲]

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See detailEffect of host plants on the abundance of Aphis craccivora Koch (Homoptera : Aphididae) and it parasitism by three parasitoids (Hymenoptera: Braconidae, Pteromalidae, Encyrtidae, ) in green space of Université des Sciences et Techniques de Masuku(USTM, Franceville), Gabon
Poligui, René Noël ULg; Francis, Frédéric ULg; Haubruge, Eric ULg et al

Poster (2010, May 05)

The cow pea aphid, Aphis craccivora Koch were studied on tree wield weeds of lawn (Paspalum sp, Poaceae), Chrysopogon aciculatus (Retz.) Trin. (Poaceae), Sporobolus indicus (L.) R.Br. (Poaceae) and ... [more ▼]

The cow pea aphid, Aphis craccivora Koch were studied on tree wield weeds of lawn (Paspalum sp, Poaceae), Chrysopogon aciculatus (Retz.) Trin. (Poaceae), Sporobolus indicus (L.) R.Br. (Poaceae) and Brachiara decumbens Stapf (Poaceae). 120 infloscences of each host plant specie were examined. The hymenopteran parasitism was based on mummified aphids. In the ascending order of infestation, A.craccivora colonies were less abundant on S.indicus (192 aphids), abundant on C.aciculatus (1546) and highly abundant on B.decumbens (2986). Parasitism on aphids is very low on B.decumbens (7,57%), high on C.aciculatus(57,12%) and very high on S.indicus (82,05%). 410 hymenopteran parasitoids hatch from 500 mummufied aphids taken on S.indicus, for 153 Aphidius sp(Braconidae) individuals ,160 (39,02%) Ceroplastes sp (Pteromalidae) and 97(23, 66%) non identified encyrtid(encyrtidae). Aphidophagous larva of Cheilomenes sulfurea (Coccinelidae) and Platynaspsis capicola Crotch (Coccinellidae) were observed predatoring aphids respectively on C.aciculatus and S.indicus.This study highlight the presence of native beneficials that can be used as biological control agents. [less ▲]

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See detailNeural correlates of cognitive control at the item specific level in the Stroop task
Grandjean, Julien ULg; D'Ostilio, Kevin ULg; Fias, Wim et al

Poster (2010, May 04)

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See detailCharacterization of clay from northern of Morocco for their industrial application
El Ouahabi, Meriam ULg; Fagel, Nathalie ULg

Poster (2010, May 04)

Clays are a natural resource used for millennia. Currently applications such as industrial minerals are diversified. In this context, our goal is to estimate the potential of the many clay deposits in ... [more ▼]

Clays are a natural resource used for millennia. Currently applications such as industrial minerals are diversified. In this context, our goal is to estimate the potential of the many clay deposits in northern of Morocco. The choice of this region is justified by the particular abundance of clay deposits used to manufacture building materials (brick, ceramic and refractories) and pottery. This study focuses on the mineralogical, chemical and geotechnical characterization tests carried out on Tangier-Tetouan and Meknes clays from northern of Morocco. The suitability of raw clay material from those regions in order to produce ceramic and brick has not been tested yet. The results revealed that the studied samples are diversified, kaolinite and illite (Tetouan clay) and kaolinite and illite and smectite and vermiculite (Tangier and Meknes clay) based materials. There were no major differences in grain-size distribution, whereas Meknes clay was more plastic than Tetouan-Tangier clay. The cation exchange capacity show that Meknes and Tangier clay were more important than Tetouan clay. Specific surface area and thermal analaysis complete this caracterization. It was found that almost all technological properties of the Meknes clay deposit are led to the manufacture of ceramic floor tile, and Tetouan-Tangier clay provide opportunities to making brick and ceramic floor. The Tetouan- Tangier and Meknes clay are a potential ceramic raw material for growing Morrocan ceramic tile and brick industries [less ▲]

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See detailAlginate-microparticles coated with chitosan and loaded with synthetic ligands for specific removal of proteins
Petkova, E; Selina, O; Bovin, N et al

Poster (2010, May 03)

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See detailDissolved inorganic carbon dynamics and air-sea carbon dioxide fluxes during coccolithophorid blooms in the Northeast European continental margin (northern Bay of Biscay)
Suykens, Kim; Delille, Bruno ULg; Chou, Lei et al

Poster (2010, May 03)

Balch et al. (2007) evaluated global pelagic contemporary calcification from remote sensing data (mainly associated to coccolithophores) to 1.6 ± 0.3 Pg PIC yr-1 (1 Pg = 1015 g; PIC = particulate ... [more ▼]

Balch et al. (2007) evaluated global pelagic contemporary calcification from remote sensing data (mainly associated to coccolithophores) to 1.6 ± 0.3 Pg PIC yr-1 (1 Pg = 1015 g; PIC = particulate inorganic carbon). This would imply that coccolithophores would be the most important pelagic calcifier in the oceans, since other estimates of contemporary global pelagic calcification range between 0.7 Pg PIC yr-1 based on accumulation rates and sediment trap data (Milliman et al. 1999), and 1.4 Pg PIC yr-1, based on the seasonal cycle of total alkalinity (TA) in the euphotic zone (Lee 2001). The development of coccolithophorid blooms affects the seawater carbonate chemistry, and air-sea CO2 fluxes, through the organic carbon pump and the carbonate counter-pump. The ratio between calcification (carbonate counter-pump), and organic carbon production (organic carbon pump), the C:P ratio, depends on the life cycle (bloom development), and growth conditions of coccolithophores. At the onset of the coccolithophorid bloom, when nutrients are available for growth, organic carbon production dominates over calcification (C:P << 1, the so-called organic phase). At the end of the bloom, in nutrient depleted conditions, and high irradiances (due to stronger stratification), organic carbon production decreases and calcification increases (C:P ≤ 1, the so-called inorganic phase). Several manipulative experiments to test the effect of ocean acidification on coccolithophores have shown that while calcification would decrease, the export of organic carbon would increase mainly through increasing transparent exopolymer particles (TEP) production. For a credible implementation in mathematical models of such feed-back mechanisms to allow the projection of a future evolution of carbon biogeochemistry under global change, it is required to understand present day biogeochemistry and ecology of naturally occurring pelagic calcifying communities. In particular, the overall effect of phytoplankton communities on the C:P ratio, and the net effect on carbonate chemistry, and related air-sea CO2 fluxes. [less ▲]

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See detailMicrowave data and a regional climate model for studying the Greenland ice sheet surface mass balance over 1979-2009
Fettweis, Xavier ULg; Marco, Tedesco

Poster (2010, May 03)

Results (melt extent and winter accumulation) from an atmosphere-snow coupled regional climate model are compared with microwave brightness temperatures-derived estimates to study the surface mass balance ... [more ▼]

Results (melt extent and winter accumulation) from an atmosphere-snow coupled regional climate model are compared with microwave brightness temperatures-derived estimates to study the surface mass balance (SMB) changes over the Greenland ice sheet (GrIS) since 1979. Two simple algorithms are selected to retrieve the melt extent from the brightness temperatures. The first one is sensible to the production of surface meltwater as suggests the regional model and the second one is rather sensible to the presence of liquid water content into the snowpack. Both algorithms compare very well with model outputs and they are unanimous to show a significant increase of the surface melt over 1979-2009.We found also a good correlation between the March-April mean brightness temperatures and the simulated winter snow accumulation although no significant changes are found in both simulated and microwave-derived snow accumulation. The interannual variability of the brightness temperature-derived SMB components compare very well with the model results. This suggests that the variability of the model is reliable and that the model can be used to detect SMB changes over longer periods where no satellite data is available. Finally, both model and satellite agree to confirm the acceleration of the GrIS surface melting since 30 years. [less ▲]

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See detailBenthic remineralization in the northeast European continental margin (northern Bay of Biscay)
Suykens, Kim; Schmidt, Sabine; Delille, Bruno ULg et al

Poster (2010, May 02)

We report a data-set of sediment characteristics and biogeochemical fluxes at the water-sediment interface at the northeast European continental margin (northern Bay of Biscay). Cores were obtained in ... [more ▼]

We report a data-set of sediment characteristics and biogeochemical fluxes at the water-sediment interface at the northeast European continental margin (northern Bay of Biscay). Cores were obtained in June 2006, May 2007 and 2008, at 8 stations on the shelf break (120 to 180 m), and at 2 stations on the continental slope (520 m and 680 m). Sediment-water fluxes of dissolved oxygen (O2), total alkalinity (TA), nitrate (NO3-), and dissolved silicate (DSi) were measured at a total of 20 stations. Sediment characteristics include: grain size, chlorophyll-a (Chl-a) and phaeopigment (Phaeo) content, particulate organic (POC) and inorganic (PIC) carbon content, and 234Th and 210Pb activities. Sediments were sandy (fine to coarse) with organic matter (OM) (1.0 - 4.0 %) and Chl-a (0.01 - 0.95 µg g-1) contents comparable to previous publications in the same region, and a relatively high PIC fraction (0.8 - 10.2 %). Sediment-water O2 fluxes (-2.4 to -8.4 mmol O2 m-2 d-1) were low compared to other coastal environments and correlated well with OM and Chl-a content. 234Th activity profiles indicated that Chl-a sediment content (apparently the main driver of total benthic organic carbon degradation) was mainly controlled by physical mixing processes related to local hydrodynamics. The correlation between sediment-water fluxes of O2 and NO3- indicated a close coupling of nitrification/denitrification and total benthic organic carbon degradation. Dissolution of biogenic silica (0.05 to 0.95 mmol m-2 d-1) was uncoupled from organic carbon degradation, characterized by sediment-water O2 fluxes. The link between sediment-water fluxes of TA and O2 indicated metabolic driven dissolution ( 0.33 +/- 0.47 mmol m-2 d-1) of calcium carbonates (CaCO3) in the sediments which represented ~1 % of the pelagic calcification rates due to coccolithophores. These rates were below those reported in sediments of continental slopes and of the deep ocean, probably due to the high over-saturation with respect to CaCO3 of the water column overlying the continental shelf sediments of the northern Bay of Biscay. Rates of total benthic organic carbon degradation and CaCO3 dissolution were low compared to water column rates of primary production, aphotic community respiration and CaCO3 production obtained during the cruises. [less ▲]

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See detailDissolved inorganic carbon dynamics and air-sea carbon dioxide fluxes during coccolithophorid blooms in the Northeast European continental margin (northern Bay of Biscay)
Suykens, Kim; Delille, Bruno ULg; Chou, Lei et al

Poster (2010, May 02)

We present a data-set of dissolved inorganic carbon (DIC) obtained during three cruises in the northern Bay of Biscay carried out in June 2006, May 2007, and May 2008. During these cruises, blooms of ... [more ▼]

We present a data-set of dissolved inorganic carbon (DIC) obtained during three cruises in the northern Bay of Biscay carried out in June 2006, May 2007, and May 2008. During these cruises, blooms of coccolithophores occurred, as indicated by patches of high reflectance on remote sensing images, phytoplankton pigment signatures, and microscopic examinations. Total alkalinity (TA) showed a non-conservative behaviour as a function of salinity due to the cumulated effect of net community calcification (NCC) during bloom development on seawater carbonate chemistry. The cumulated impact of NCC and net community production (NCP) on DIC and the partial pressure of CO2 (pCO2) were evaluated. The decrease of DIC (and increase of pCO2) due to NCC was overwhelmingly lower than the decrease of DIC (and decrease of pCO2) due to NCP (NCC:NCP « 1). During the cruises, the northern Bay of Biscay acted as a sink of atmospheric CO2 (on average -9.7 mmol C m-2 d-1 for the 3 cruises). The overall effect of NCC in decreasing the CO2 sink during the cruises was low (on average 12% of total air-sea CO2 flux). If this is a general feature in naturally occurring phytoplankton blooms in the northern North Atlantic Ocean (where coccolithophorid blooms are the most intense and recurrent), and in the global ocean, then the potential feed-back on increasing atmospheric CO2 of the projected decrease of pelagic calcification due to thermodynamic CO2 “production” from calcification is probably minor compared to feed-backs related to changes of NCP. [less ▲]

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See detailβ3 integrin sequence variation and rodent susceptibility to hantaviruses
Pagès, Marie ULg; Tatard, Caroline; Galan, Maxime et al

Poster (2010, May)

Detailed reference viewed: 15 (0 ULg)
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See detailVOC emissions from a temperate mixed forest in Belgium measured by eddy-covariance
Laffineur, Quentin ULg; Heinesch, Bernard ULg; Aubinet, Marc ULg et al

Poster (2010, May)

Forest ecosystems are known to be important emitters of Biogenic Volatile Organic Compounds (BVOC). They play an important role in the atmospheric chemistry and may contribute to the formation of ozone ... [more ▼]

Forest ecosystems are known to be important emitters of Biogenic Volatile Organic Compounds (BVOC). They play an important role in the atmospheric chemistry and may contribute to the formation of ozone and aerosols with consequences on air quality and on climate. In order to better understand the effects of environmental parameters on the emissions, micrometeorological flux measurements were carried out above a mixed forest (Fagus sylvatica, Pseudotsuga menziesii, Abies alba, Picea abies) at the Vielsalm experimental site (Belgium) from July to November 2009. The flux measurements were obtained by the eddy-covariance technique using proton transfer reaction mass spectrometry. In our first measurement campaign, among other VOC compounds, isoprene (m/z 69) and monoterpenoid compounds (m/z 137) have been measured continuously with a data coverage of 75 and 58 % respectively, allowing robust statistical analysis. In our analysis, we focused on these two main emissions. A footprint analysis showed that Fagus sylvatica seems to be the main emitter of m/z 137 and Abies alba seems to be the main emitter of m/z 69. BVOCs fluxes present an exponential response to temperature. This response is more pronounced for m/z 69 while it shows the strongest seasonal evolution for m/z 137. A light dependence of m/z 69 and m/z 137 fluxes was observed but the relationship did not exhibit the same behaviour before (hyperbolic relation) and after midday (linear relation). This behaviour difference induced a hysteresis effect on the daily evolution of averaged fluxes. A robust local minimum was also observed just before midday for m/z 69 (less obvious for m/z 137) during July-August period. This minimum is not observed in the CO2 fluxes which are also measured in Vielsalm. The light dependence of BVOC emissions suggests that m/z 69 and m/z 137 emissions are directly linked to the photosynthetic cycle but the presence of the midday local minimum suggests that other processes influence the measured BVOC fluxes. As for the relation with air temperature, a seasonal evolution of flux-light dependence was far more evident for m/z 137 than for m/z 69. This seasonal variation could be explained by a phenological effect. As Fagus sylvatica is the main m/z 137 emitter, its flux is probably influenced by leaves ageing while m/z 69, as mainly emitted by Abies alba, is less influenced by needles ageing. A wind speed dependence of BVOCs fluxes was also observed, the flux increasing linearly with wind speed. This surprising result will be discussed. [less ▲]

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See detailTestosterone increases cell turnover in song nucleus HVC and increases cell recruitment into Area X of adult female canaries.
Barker, Jennifer ULg; Yamamura, Takashi; Balthazart, Jacques ULg et al

Poster (2010, May)

In songbirds, song control nuclei such as HVC and Area X, show seasonal changes in volume that are regulated, at least in part, by the action of gonadal testosterone (T) and its metabolites. These changes ... [more ▼]

In songbirds, song control nuclei such as HVC and Area X, show seasonal changes in volume that are regulated, at least in part, by the action of gonadal testosterone (T) and its metabolites. These changes in volume are a result of changes in cell size, dendritic branching and, in HVC, the incorporation of newborn neurons. Doublecortin (DCX) is a microtubule-associated protein expressed during development and in adulthood in post-mitotic migrating and differentiating neurons in mammals. Our previous studies in male canaries demonstrated that DCX is expressed in BrdU-positive neurons consistent with DCX being a marker of neurogenesis in adult canaries. Testosterone induces marked increases in song nuclei volume in adult female canaries making these nuclei more male-like. Within the songbird brain, T can be metabolized to 5 alpha-dihydrotestosterone (DHT) and 17 beta-estradiol (E2). We found previously that both these metabolites are required to increase the volume of song nuclei in adult female canaries, but the cellular basis of this adult neuroplasticity is not well understood. Within HVC, the number of DCX-immunoreactive (ir) cells can be increased by photostimulation or treatment with T, but the effects of T and its metabolites on cell death in the songbird brain had not yet been elucidated. We therefore examined the effect of DHT and E2 on DCX expression and cell death in the song nuclei of adult female canaries. Intact female canaries were implanted with Silastic tubing containing crystalline T, DHT, E2, or a combination of DHT+E2. Control animals received empty implants. All birds were kept under early spring-like photoperiodic conditions (11L:13D) for 3 weeks. In HVC, the total number of DCX-ir cells was increased by treatment with T or DHT+E2 as compared to control birds, but was not affected by treatment with DHT or E2 alone. The number of pyknotic cells observed in the HVC was also increased by T but not by its metabolites. In Area X, the total number of DCX-ir cells was increased by treatment with T or DHT+E2, but the number of pyknotic cells was unaffected by hormone treatment. These results suggest that T enhances cellular turnover in the HVC (migration into, and cell death within, HVC), but affects only recruitment of new neurons into Area X. [less ▲]

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

Poster (2010, May)

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

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

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See detailOrganochlorine pollutants in sea turtles and their association with vitamin A
Dyc, Christelle ULg; Debier, Cathy; Thomé, Jean-Pierre ULg et al

Poster (2010, May)

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See detailStudy of the role of miR-21 in the regulation of angiogenesis
Sabatel, Céline; Malvaux, Ludovic; Bovy, Nicolas ULg et al

Poster (2010, May)

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See detailL’Inventaire Systémique de Qualité de Vie en oncologie pédiatrique : développement d’un module spécifique
Missotten, Pierre ULg; Hoyoux, Claire; Dupuis, Gilles et al

Poster (2010, May)

Introduction Dans la littérature pédiatrique relative à l’évaluation de la qualité de vie et de la qualité de vie liée à la santé, deux types bien distincts d’outils existent: les outils génériques et les ... [more ▼]

Introduction Dans la littérature pédiatrique relative à l’évaluation de la qualité de vie et de la qualité de vie liée à la santé, deux types bien distincts d’outils existent: les outils génériques et les outils spécifiques. Les mesures génériques s’adressent à tout enfant (Rodary, 2000). Elles permettent d’établir des comparaisons entre différents groupes d’enfants (malades et sains) mais peuvent ne pas être sensibles ni aux changements mineurs dans le fonctionnement d’un enfant ni aux aspects spécifiques de la maladie qui sont pourtant cliniquement pertinents dans sa vie (Harding, 2001; Patrick & Erikson, 1993; Raat et al., 2006). Les mesures spécifiques concernent les enfants atteints d’une maladie donnée: asthme, diabète, cancer,… (Rodary, 2000). Elles sont plus sensibles aux implications des différents traitements et sont probablement plus appropriées tant pour évaluer les interventions que pour comparer l’impact de traitements alternatifs (Eiser, 1997). Par contre, elles ne permettent pas de comparer la qualité de vie d’enfants et d’adolescents souffrant de maladies différentes (Levi & Drotar, 1998). De plus, leur spécificité s’oppose à la conception de la qualité de vie en tant que construction applicable à tous les enfants, les standards de qualité de vie étant universels (Wallander et al., 2001). Pour contrer ces inconvénients respectifs, le développement d’un troisième type d’outil -l’outil modulaire- est actuellement encouragé. Ce dernier se compose d’une partie générique à laquelle vient s’ajouter une partie spécifique à la pathologie. Objectif L’objectif de cette communication est de présenter le développement d’un module spécifique « cancer » se rattachant à la partie générique de l’Inventaire Systémique de Qualité de Vie pour Enfants (ISQV-E© ; Missotten, Etienne et Dupuis, 2007) et Adolescents (ISQV-Ados© ; Missotten, 2007). L’ISQV-E© et l’ISQV-Ados© sont des auto-questionnaires, respectivement destinés aux enfants de 8 à 12 ans et aux adolescents de 13 à 18 ans. Ils se différencient tant au niveau du contenu de certains items qu’au niveau du matériel proposé. Toutefois, tous deux évaluent dans quelle mesure chaque enfant ou adolescent parvient à atteindre les buts qu’il se fixe dans différents domaines de sa vie. Ces derniers recouvrent principalement le fonctionnement physique, le fonctionnement émotionnel, le fonctionnement social et familial et le fonctionnement cognitif. La spécificité de ces questionnaires tient à leur évaluation de la qualité de vie en termes d’écart entre la situation actuelle du jeune et son attente (but) et à leur prise en compte des capacités d’adaptation des enfants et adolescents. Méthode L’élaboration du module spécifique venant s’ajouter aux items génériques a été effectuée sur base de deux types d’informations: - discussions multidisciplinaires réunissant l’ensemble de l’équipe d’hémato-oncologie pédiatrique du CHR de la Citadelle. - recensement des outils spécifiques existant en oncologie pédiatrique et du seul outil modulaire ayant un module cancer : le Pediatric Quality of Life Inventory (Varni et al., 2002). Résultats Sur base de ces informations, 6 items spécifiques ont été générés: nausées et vomissements, fonctionnement physique, anxiété liée aux traitements, connaissance de la maladie, des traitements et de leurs effets, relations avec le personnel soignant et fonctionnement intellectuel. Ces 6 items spécifiques sont appréhendés, de manière similaire aux items génériques, et donc de manière différente chez l’enfant et l’adolescent. [less ▲]

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See detailUtilisation optimisée de GATE sur un cluster Sun Grid Engine
Taleb, Dounia ULg; Seret, Alain ULg

Poster (2010, May)

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See detailGlass production in Merovingian time
Van Wersch, Line ULg; Mathis, François ULg; Othmane, G. et al

Poster (2010, May)

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See detailEnfants en et hors traitements oncologiques : analyse comparative de leur qualité de vie et de leur vécu émotionnel
Missotten, Pierre ULg; Badot, Isabelle; Hoyoux, Claire et al

Poster (2010, May)

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See detailEfficient access pricing and endogenous market structure
Gautier, Axel ULg

Poster (2010, May)

We investigate how a regulatory mechanism can influence the nature of competition in a network industry. In the downstream market, the seller of a differentiated retail product competes with an incumbent ... [more ▼]

We investigate how a regulatory mechanism can influence the nature of competition in a network industry. In the downstream market, the seller of a differentiated retail product competes with an incumbent firm. The incumbent firm is also the owner of the essential input. The regulator may or may not observe the cost of the entrant. To maximize social welfare the regulator specifies the access charge that the entrant must pay to the incumbent, and the retail prices. The optimal access charge is a uniform price that respects the criteria of transparency and non-discrimination that are imposed by the competition and regulation directives in most countries. We derive new formulas for retail and access prices adhering to the traditional Ramsey rule. Since the competing firm takes the decision to enter following the choice of the regulatory regime, the nature of the retail market competition is endogenous [less ▲]

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See detailUpdating hydrogen fluoride (HF) FTIR time series above Jungfraujoch: comparison of two retrieval algorithms and impact of line shape models
Duchatelet, Pierre ULg; Demoulin, Philippe ULg; Hase, Frank et al

Poster (2010, May)

Fluorine enters the stratosphere mainly in the form of chlorofluorocarbons (CFCs; principally CFC-11 and CFC-12) and tetrafluoromethane (CF4), which have been widely emitted at ground level by human ... [more ▼]

Fluorine enters the stratosphere mainly in the form of chlorofluorocarbons (CFCs; principally CFC-11 and CFC-12) and tetrafluoromethane (CF4), which have been widely emitted at ground level by human activities over the past few decades. In the lower stratosphere, the photolysis of the long-lived CFC-11 (CCl3F) and CFC-12 (CCl2F2), whose emissions from the ground have been progressively phased out by the Montreal Protocol and its successive Amendments and Adjustments, leads to the formation of the two reservoirs: COClF and COF2. Subsequent photolysis of these two compounds then liberates F atoms, which could quickly react with CH4, H2O or H2 to form the extreme stable hydrogen fluoride (HF) gas. The formation of HF by these reactions is significant, as they make HF the largest fluorine reservoir in the middle and upper stratosphere. Despite the fact that fluorine does not directly participate in ozone depletion, measurements of the concentration of individual F-containing species at different altitude of the atmosphere are important as they reflect the amounts of anthropogenic gases – which also often bear ozone-threatening Cl atoms - transported into the middle atmosphere as well as their decomposition. Since the first detection of hydrogen fluoride in the Earth’s atmosphere by Zander (1975), several studies dealing with HF total column amounts derived from ground-based Fourier transform infrared (FTIR) observations at several latitudes in both hemispheres have been published. In addition, these last years have seen the emergence of more sophisticated retrieval algorithms (e.g. SFIT-2, PROFFIT) allowing to inverse total or partial columns as well as vertical distribution of the target gas from ground-based FTIR spectra. In this contribution, we propose to compare HF total columns derived from FTIR high-resolution ground-based observations performed at the Jungfraujoch (46.5°N, 8.0°E, 3580 m asl) by using two different retrieval codes: SFIT-2 v.3.91 and PROFFIT v.9.5. The impact of spectroscopic parameters (Voigt line shape model versus Galatry model line shape) on HF retrievals is also analyzed. References: Zander, R.: Présence de HF dans la stratosphère supérieure, C.R. Acad. Sci. Paris. Série B., 281, 213-214, 1975. [less ▲]

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See detailInfluence de l'ajout de co-solvant pour l'estérification du D-mannose et de l'acide D-glucuronique assistée par les lipases
Richard, Gaetan ULg; Brognaux, Alison ULg; Nott, Katherine ULg et al

Poster (2010, May)

En parallèle à la production de biocarburant, le second objectif du bioraffinage est la transformation des sucres issus de l’hydrolyse de la lignocellulose en produits d’intérêt, qui se substitueront aux ... [more ▼]

En parallèle à la production de biocarburant, le second objectif du bioraffinage est la transformation des sucres issus de l’hydrolyse de la lignocellulose en produits d’intérêt, qui se substitueront aux produits de la vie courante issus du pétrole. L’une des voies de valorisation envisageable est la synthèse de molécules amphiphiles par greffage de chaînes grasses sur le sucre. Ces composés trouveraient alors des applications dans de très nombreux domaines utilisant les tensioactifs (alimentaire, détergence, peinture,…) . Dans le cadre du programme d’excellence TECHNOSE et du projet d’Action de Recherche Concertées SUPERZYM, deux sucres ont été testés : un polyol, le D-mannose, et un sucre acide, l’acide D-glucuronique. Afin de conférer un caractère amphiphile à la molécule, les lipases ont été utilisées en tant qu’outils d’estérification. Ces triglycérides hydrolases sont en effet capables de catalyser ce type de réaction, et de nombreux exemples dans la littérature démontrent le fort potentiel industriel de ces enzymes , . L’estérification du D-mannose et de l’acide D-glucuronique a donc été mise en œuvre en présence de la lipase de Candida antarctica B (Novozyme 435). La réaction est effective, mais l’ajout de co-solvants tels que la pyridine ou le DMSO améliore les vitesses initiales et les rendements de la réaction. Ces améliorations seront discutées et comparées sur ce poster. [less ▲]

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See detailEvaluation du potentiel de récupération d’énergie à l’échappement d’un moteur TDI à l’aide d’un cycle de Rankine organique (ORC)
Declaye, Sébastien ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

Poster (2010, May)

Une étude expérimentale a été menée sur un cycle de Rankine organique de faible puissance (2,5kW). Les résultats expérimentaux ont permis de calibrer un modèle du cycle qui a ensuite été utilisé afin ... [more ▼]

Une étude expérimentale a été menée sur un cycle de Rankine organique de faible puissance (2,5kW). Les résultats expérimentaux ont permis de calibrer un modèle du cycle qui a ensuite été utilisé afin d’évaluer le potentiel de récupération d’énergie à l’échappement d’un moteur TDI pour 13 points de fonctionnement représentatifs. Les résultats montrent la possibilité de produire jusqu’à 2,4kW de puissance mécanique additionnelle. La fraction d’énergie récupérée (ERR) pouvant atteindre 6,8% de la puissance à l’arbre moteur. [less ▲]

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See detailResponse of the European ecosystems to climate change: a modelling approach for the 21st century
Dury, Marie ULg; Warnant, Pierre; François, Louis ULg et al

Poster (2010, May)

According to projections, over the 21st century, significant climatic changes appear and will be strengthened all over the world with the continuing increase of the atmospheric CO2 level. Climate will be ... [more ▼]

According to projections, over the 21st century, significant climatic changes appear and will be strengthened all over the world with the continuing increase of the atmospheric CO2 level. Climate will be generally warmer with notably changes in the seasonality and in the precipitation regime. These changes will have major impacts on the environment and on the biodiversity of natural ecosystems. Geographic distribution of ecosystems may be modified since species will be driven to migrate towards more suitable areas (e. g., shifting of the arctic trees lines). The CARAIB dynamic vegetation model (Carbon Assimilation in the Biosphere) forced with 21st century climate scenarios of the IPCC (ARPEGE-Climat model) is used to illustrate and analyse the potential impacts of climate change on tree species distribution and productivity over Europe. Changes in hydrological budget (e. g., runoff) and fire effects on forests will also be shown. Transient runs (1975-2100) with a new dynamic module introduced in CARAIB are performed to follow the future evolutions. In the new module, the processes of species establishment, competition and mortality due to stresses and disturbances have been improved. Among others, increased atmospheric CO2 and warmer climate increase tree productivity while drier conditions decrease it. Regions with more severe droughts will also be affected by an increase of wildfire frequency, which may have large impacts on vegetation density and distribution. [less ▲]

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See detailOntogeny of sex differences in steroid-sensitive regions in the quail brain (Coturnix Japonica)
Mouriec, Karen ULg; Bardet, Sylvia; Balthazart, Jacques ULg

Poster (2010, May)

Sex differences affecting the expression of sexual behavior are observed in many species. In quail, expression of the male-typical copulatory pattern is androgen-dependent. This behavior disappears within ... [more ▼]

Sex differences affecting the expression of sexual behavior are observed in many species. In quail, expression of the male-typical copulatory pattern is androgen-dependent. This behavior disappears within a week after castration and is restored after a few days of treatment with exogenous testosterone. In contrast, ovariectomized females treated with testosterone never show the sequence of male-typical copulatory behavior. This sex difference in responsiveness to testosterone results from organizational effects of embryonic estrogens secreted by the female ovary. The behavioral phenotype can be completely reversed by treatment, before embryonic day 12, of male embryos with estrogens or of female embryos with an aromatase inhibitor. In the quail brain, the medial preoptic nucleus (POM) is a necessary and sufficient site for the activation by testosterone of sexual behavior. Aromatase, the enzyme converting testosterone into estradiol, is densely expressed in POM and its activity is sexually differentiated (males>females) even when birds are treated with a same dose of testosterone. Aromatase and other neuroendocrine systems are thus, like sexual behavior, differentially activated by testosterone in adult quail but the cellular basis of these sexually differentiated features presumably organized in early life by steroid action have not been identified. To analyze the ontogeny of steroid sensitive regions that control behavioral sex differences in the quail brain, we injected 5-bromo-2-deoxyuridine (BrdU) in eggs at different stages of the embryonic (E) development (E8, E10, E12, E14 and E16) and sacrificed the animals at postnatal (PN) day 56. Large numbers of BrdU-positive cells were observed throughout the POM of males and females injected on E8-E10 but most cells were post-mitotic in both sexes on E14-E16. E12 injections resulted in a larger number of BrdU cells in females than in males. This differential number of BrdU-positive cells seen at PN56 in birds injected on E12 could result from a) a difference in the age at which cells become post-mitotic (males before females or alternatively females before males, so that male cells labeled by BrdU on E12 dilute their label in subsequent divisions) or b) a differential apoptosis between E13 and PN56. However, no sex differences in the number of BrdU positive cells was observed in embryos injected with BrdU on E12 and killed on E13. Furthermore, BrdU injections on E14 labeled very few cells at PN 56 suggesting that the POM is essentially post-mitotic at that age. The sex difference observed in birds injected at E12 should result from a differential apoptosis after E13. Double-label immunohistochemistry for BrdU and the neuronal marker Hu (C/D) indicated that all BrdU-positive cells born between E8 and E16 are not neurons (no double label) suggesting that these are glial cells. This sex difference in (glial?) proliferation around the end of the critical period of sexual differentiation may play a key role in the differentiation of brain and behavior. The specific phenotype of these cells and the mechanisms mediating their differential development are currently under investigation. [less ▲]

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See detailFalse memories and hemispheric processing in aging
Gajewski, Celine; Dehon, Hedwige ULg; Peigneux, Philippe ULg et al

Poster (2010, May)

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See detailLes inventaires forestiers par échantillonnage comme outil d’aide à la gestion : exemple d’application au Domaine royal de Ciergnon
Gheysen, Thibaut ULg; Arnould, Dominique; Nachtergaele, Quentin et al

Poster (2010, May)

Ce poster présente un exemple concret de mise en oeuvre d’inventaire forestier de gestion sur un massif d’environ 5000 ha de forêt situé en Wallonie. L’objectif est de fournir au gestionnaire un tableau ... [more ▼]

Ce poster présente un exemple concret de mise en oeuvre d’inventaire forestier de gestion sur un massif d’environ 5000 ha de forêt situé en Wallonie. L’objectif est de fournir au gestionnaire un tableau de bord rassemblant les principaux indicateurs décrivant l’état de son patrimoine forestier. Le plan d’échantillonnage est constitué d’une grille systématique comportant 1 point de sondage par 4 ha. Les points sont permanents et visités tous les 4 ans. Les informations, délivrées dans un rapport d’inventaire standardisé, concernent notamment : la surface terrière et le volume par ha, la structure, la composition, l’état de la régénération, le potentiel biomasse, la diversité spécifique et les accroissements. [less ▲]

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See detailInventaire sur l’affectation des terres de la Belgique dans le cadre du Protocole de Kyoto et de la CCNUCC
Bauwens, Sébastien ULg; Hebert, Jacques ULg; Lejeune, Philippe ULg

Poster (2010, May)

La Belgique réalise annuellement un inventaire de ses émissions de gaz à effet de serre (GES) dans le cadre du Protocole de Kyoto et de la Convention Cadre des Nations Unies sur les Changements ... [more ▼]

La Belgique réalise annuellement un inventaire de ses émissions de gaz à effet de serre (GES) dans le cadre du Protocole de Kyoto et de la Convention Cadre des Nations Unies sur les Changements Climatiques (CCNUCC/UNFCCC). L’affectation des terres et le changement d’affectation des terres (LULUCF) forment l’un des cinq principaux secteurs qui doivent être rapportés dans cet inventaire national. Ce poster présente la méthode mise en œuvre au niveau de la Belgique pour réaliser le rapportage de ce secteur, ainsi que les résultats pour 1990 et 2008. [less ▲]

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