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See detailNew elicitors to protect wheat against Zymoseptoria tritici: biocontrol tools for IPM strategies
Le Mire, Géraldine ULg; SIAH, Ali; BRISSET, Marie-Noëlle et al

Conference (2016, May 17)

Elicitors are increasingly considered as promising biocontrol tools in the preventive treatment of plants against various diseases. These plant-immunity triggering compounds, also called “stimulators of ... [more ▼]

Elicitors are increasingly considered as promising biocontrol tools in the preventive treatment of plants against various diseases. These plant-immunity triggering compounds, also called “stimulators of plant natural defenses”, induce a general and systemic resistance of the plant to a large spectrum of biotic stresses. Today, focus is made on the crucial protection of wheat, as one of the most cultivated crop plants in the world. This crop is constantly challenged by a persistent and harmful fungus known as Zymoseptoria tritici, responsible of the Septoria Tritici Blotch (STB) disease. Control of this disease mainly depends on phytosanitary products, and the social and economic importance of wheat make it all the more urgent to identify and develop new elicitors as biocontrol tools in wheat IPM strategies. This study focuses on the screening of nine molecules of various origins and structures for their potential eliciting properties to protect winter wheat against Zymoseptoria tritici. Three products were selected after screening trials in greenhouse conditions: EGL1, EGL4, and EGL5. They were efficient to reduce foliar disease symptoms from 40 to 80%. The biocide activity and phytotoxicity of these 3 products were evaluated directly towards the pathogen and the plant under laboratory and greenhouse conditions, respectively. On the other hand, the triggered signaling pathways were investigated by studying the activity of the defense-related enzymes lipoxygenase (LOX), peroxidase (POX) and phenylalanine ammonia-lyase (PAL) in treated wheat leaves. In addition, the expression of five defense genes (lox, pal, pox2, chi, pr1) was studied by qRT-PCR in wheat leaves treated with these elicitors and/or inoculated with Zymoseptoria tritici. The corresponding results will be presented and discussed, with the perspective to investigate the influence of environmental parameters on the elicitation capacity and the efficacy of the elicitors in field conditions. [less ▲]

Detailed reference viewed: 34 (6 ULg)
See detailDevelopment of a semiochemical-based control method against the walnut husk fly
Sarles, Landry ULg; Heuskin, Stéphanie ULg; Verheaghe, Agnès et al

Conference (2016, May 17)

Detailed reference viewed: 8 (1 ULg)
Peer Reviewed
See detailHerbicidal activity of Tunisian plant extracts against various weeds
Ben Kaab, Sofiène ULg; Parisi, Olivier ULg; Ksouri, Riadh et al

Conference (2016, May 17)

In agricultural systems, weeds can dramatically reduce crop yields (by the constant competition for water and nutrients) and interfere with plant functions to suppress their growth causing huge economic ... [more ▼]

In agricultural systems, weeds can dramatically reduce crop yields (by the constant competition for water and nutrients) and interfere with plant functions to suppress their growth causing huge economic losses.Yield losses can reach up to 34% in crops. Plant extracts are known since a long time to have phytotoxicity potentialities and could be used as new natural compounds with bioherbicide activities. The study began with the selection of ten plant species suspected to be phytotoxic due to their wealth of phenolic, terpene and alcaloid compounds, such as flavonoids and phenolic acids coumarins. Then, three weeds were selected from Maghreb and European weeds as models (Phalaris minor, Sylibum marianum and Trifolium incanatum). Aerial plant materials were grounded and macerated with methanol for 24H. Methanol was then eliminated along rotavapor. The yield of plant extract varied between 5.29% and 29.71 % following the species. The essential oil was extracted by hydrodistillation using a Clevenger type apparatus (with a yield of 1.2%). Methanol extracts and the essential oil were then tested for their herbicidal activity in post-emergence assays against the three weeds species.The most active extracts were selected and formulated to increase their efficiency. Post-emergence bioassays consisted in spraying each extract at 3 concentrations (7500, 20000 and 340000 ppm) at 2 leaves stage . Pelargonic acid was used as commercial positive control at 34000 ppm. After 7 days on incubation in greenhouses, results showed that E6, presented poor phytotoxicity against three weeds at 7500 and 20000 ppm. However, E6 caused total wilting and several leaf blight against Phalaris minor and Trifolium incanatum and sever necrosis against Sylibum marianum. At that higher concentration of 34000 ppm. , the extracts E3 and E8 and the essential oil appeared also phytotoxic. The three extracts and the essential oil were selected for the formulation. After formulation to enhance the distribution, the coverage and the penetration of the active molecules at 34000 ppm, E3, E6, E8 and essential oil presented a high herbicidal activity compared with the extracts without formulation. E6 with the formulation has completely punctured Trifolium incanatum and suppressed growth of Phalaris minor and Sylibum marianum. The results of this study reveal that plant extracts, after formulation, are more effective in inhibiting weed growth. The strong weed suppressive ability of formulated E6 therefore offers interesting possibilities as an effective natural environment-friendly approach for weed management. [less ▲]

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See detailInfluence of the balls kinematics and ball/race contact models on quasi-static approaches for ball bearing
Servais, Christophe ULg; Bozet, Jean-Luc ULg

Conference (2016, May 17)

The frictional power dissipated within dry lubricated ball bearings is a prime concern, especially for high speed applications. Nevertheless, the exact balls behavior is still a source of interrogations ... [more ▼]

The frictional power dissipated within dry lubricated ball bearings is a prime concern, especially for high speed applications. Nevertheless, the exact balls behavior is still a source of interrogations. Firstly, a comparison of several ball/race contact models has been performed by prescribing the kinematical variables. This has been done by using an existing quasi-static approach to reach the ball bearing equilibrium. Secondly, a parametric study has been carried out on the ball kinematics. This time the contact model remained fixed. The results demonstrate the predominance of the kinematics on the ball bearing behavior with an emphasis on the dissipated power within ball/race contacts. This shows that the kinematics must be rightly computed. On the other hand, the ball/race contact model doesn’t necessitate a high refinement in order to evaluate the ball bearing equilibrium. Conversely, this refinement is essential for a precise evaluation of the power losses. [less ▲]

Detailed reference viewed: 8 (3 ULg)
See detailMonstres et images : premiers pas vers une redéfinition de la monstruosité cinématographique
Jousten, Lison ULg

Conference (2016, May 17)

La communication propose un déplacement du monstre en tant qu’objet filmé pour l’envisager en tant que forme filmique. Cette hypothèse est avancée puis expérimentée par le biais d'une étude de cas.

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See detailEmbargo on Lion Hunting Trophies from West Africa: An Effective Measure or a Threat to Lion Conservation ?
Bouché, Philippe; Crosmary, William; Kafando, Pierre et al

in PLoS ONE (2016), 11(5), 0155763

The W-Arly-Pendjari (WAP) ecosystem, shared among Benin, Burkina Faso and Niger, represents the last lion stronghold of West Africa. To assess the impact of trophy hunting on lion populations in hunting ... [more ▼]

The W-Arly-Pendjari (WAP) ecosystem, shared among Benin, Burkina Faso and Niger, represents the last lion stronghold of West Africa. To assess the impact of trophy hunting on lion populations in hunting areas of the WAP, we analyzed trends in harvest rates from 1999 to 2014. We also investigated whether the hunting areas with higher initial hunting intensity experienced steeper declines in lion harvest between 1999 and 2014, and whether lion densities in hunting areas were lower than in national parks. Lion harvest rate remained overall constant in the WAP. At initial hunting intensities below 1.5 lions/1000km2, most hunting areas experienced an increase in lion harvest rate, although that increase was of lower magnitude for hunting areas with higher initial hunting intensity. The proportion of hunting areas that experienced a decline in lion harvest rate increased at initial hunting intensities above 1.5 lions/1000km2. In 2014, the lion population of the WAP was estimated with a spoor count at 418 (230–648) adults and sub-adult individuals, comparable to the 311 (123–498) individuals estimated in the previous 2012 spoor survey. We found no significant lion spoor density differences between national parks and hunting areas. Hunting areas with higher mean harvest rates did not have lower lion densities. The ratio of large adult males, females and sub-adults was similar between the national parks and the hunting areas. These results suggested that the lion population was not significantly affected by hunting in the WAP. We concluded that a quota of 1 lion/1000km2 would be sustainable for the WAP. Based on our results, an import embargo on lion trophies from the WAP would not be justified. It could ruin the incentive of local actors to conserve lions in hunting areas, and lead to a drastic reduction of lion range in West Africa. [less ▲]

Detailed reference viewed: 53 (7 ULg)
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See detailVortex Image Processing (VIP) package for high-contrast direct imaging
Gómez González, Carlos ULg; Absil, Olivier ULg; Wertz, Olivier ULg et al

Poster (2016, May 16)

VIP is a Python instrument-agnostic toolbox featuring a flexible framework for reproducible and robust data reduction. VIP currently supports three high-contrast imaging observational techniques: angular ... [more ▼]

VIP is a Python instrument-agnostic toolbox featuring a flexible framework for reproducible and robust data reduction. VIP currently supports three high-contrast imaging observational techniques: angular, reference-star and multi-spectral differential imaging. The code can be downloaded from our git repository on Github: http://github.com/vortex-exoplanet/VIP [less ▲]

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See detailEfficacy of the RemoweLL cardiotomy reservoir for fat and leucocyte removal from shed mediastinal blood: a randomized controlled trial.
LAGNY, Marc-Gilbert ULg; GOTHOT, André ULg; HANS, Grégory ULg et al

in Perfusion (2016)

Efficacy of the RemoweLL cardiotomy reservoir for Fat and Leucocyte removal from shed mediastinal blood: a randomized controlled trial. ABSTRACT (176 words) Introduction Re-transfusion of lipid particles ... [more ▼]

Efficacy of the RemoweLL cardiotomy reservoir for Fat and Leucocyte removal from shed mediastinal blood: a randomized controlled trial. ABSTRACT (176 words) Introduction Re-transfusion of lipid particles and activated leucocytes with shed mediastinal blood (SMB) can aggravate cardiopulmonary bypass-associated inflammation and increase the embolic load. This study evaluated the fat and leucocyte removal capacity of the RemoweLL cardiotomy reservoir. Methods Forty-five patients undergoing elective on-pump cardiac surgery were randomly allocated to filtration of SMB using the RemoweLL or the Admiral cardiotomy reservoir. The primary outcome was the drop in leucocytes and lipid particles obtained with the two filters. The effect of the filters on other blood cells and inflammatory mediators such as myeloperoxidase (MPO) was also assessed. Results The RemoweLL cardiotomy filter removed 16.5 % of the leucocytes (P < 0.001) while no significant removal of leucocytes was observed with the Admiral (P = 0.48). The percentage reductions in lipid particles were similar in the two groups (26% vs 23 %, P = 0.2). Both filters similarly affected the level of MPO (P = 0.71). Discussion The RemoweLL filter more effectively removed leucocytes from SMB than the Admiral. It offered no advantage in term of lipid particle clearance. [less ▲]

Detailed reference viewed: 13 (3 ULg)
See detailMonstruosité cinématographique : déployer l’écart
Jousten, Lison ULg

Scientific conference (2016, May 13)

La communication revient sur la possibilité d’étudier autrement la monstruosité cinématographique, en effectuant un pas de côté par rapport aux approches qui ont abordé le monstre comme motif. Elle ... [more ▼]

La communication revient sur la possibilité d’étudier autrement la monstruosité cinématographique, en effectuant un pas de côté par rapport aux approches qui ont abordé le monstre comme motif. Elle propose de penser l’écart dans l’écart, en déployant cette notion matricielle à au moins trois niveaux : dans la figure même du monstre, dans la nature des films envisagés, ainsi que dans la constitution du corpus. [less ▲]

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See detailVivre et faire vivre la transdisciplinarité. Retour d'expérience du cours "Approche intégrée d'une question d'environnement"
Denayer, Dorothée ULg; Melard, François ULg; Semal, Nathalie ULg

Conference (2016, May 13)

Cette communication présente la démarche pédagogique qui a mené un collectif d'enseignants, à la recherche d'une approche intégrée des questions d'environnement au développement d’une approche ... [more ▼]

Cette communication présente la démarche pédagogique qui a mené un collectif d'enseignants, à la recherche d'une approche intégrée des questions d'environnement au développement d’une approche d’apprentissage où l'entrée des publics concernés dans le dispositif d'apprentissage (Public-based-learning) permettent de faire vivre plutôt que d'enseigner aux étudiants la transdisciplinarité. Cette communication, centrée sur le collectif enseignant, developpe la dimension fondamentalement expérientielle et pratique de l’interdisciplinarité et son ancrage dans un certain type d’engagement du collectif.] [less ▲]

Detailed reference viewed: 15 (0 ULg)
See detailApproches intégrées en Sciences Pharmaceutiques
Servais, Anne-Catherine ULg; Ziemons, Eric ULg

Conference (2016, May 13)

Detailed reference viewed: 13 (1 ULg)
See detailBildwissenschaft, l’image entre signe et perception (K. Sachs-Hombach)
Hagelstein, Maud ULg; Letawe, Céline ULg

Conference (2016, May 13)

« Une science générale de l’image n’a pas (encore) réussi à s’établir » (I, §1) . Face à ce constat, Sachs-Hombach suppose qu’il serait possible – et nécessaire – de définir un « cadre théorique commun » ... [more ▼]

« Une science générale de l’image n’a pas (encore) réussi à s’établir » (I, §1) . Face à ce constat, Sachs-Hombach suppose qu’il serait possible – et nécessaire – de définir un « cadre théorique commun » et un « programme de recherche intégratif » pour les différentes disciplines concernées par la science générale de l’image. « Par cadre théorique, je comprends un ensemble de formules qui résume les hypothèses communes de différentes théories » (I, §3) . Autrement dit, le travail de définition du cadre théorique implique que l’on dégage du commun, non pas au sens d’une métathéorie surplombante qui identifierait les « conditions constitutives » des théories spécifiques/particulières, mais au sens d’une description cartographique des lieux de croisement de ces théories – envisagées du point de vue de leur contenu (c’est-à-dire essentiellement : du point de vue des moyens conceptuels mobilisés). Les outils conceptuels de base doivent être décrits et expliqués, mais aussi légitimés (telle serait la tâche proprement philosophique d’une étude critique de la Bildwissenschaft). Bien entendu, la difficulté tient au fait qu’il existe une grande variété de concepts d’image (il faut pouvoir en tenir compte), ainsi qu’une multitude de modes d’accès disciplinaires à l’expérience iconique. Le cadre théorique doit pouvoir inclure tous les phénomènes liés à l’image – et se résout par conséquent aux seules caractéristiques générales. Etablir la cartographie des « concepts fondamentaux » constitue la tache philosophique par excellence et permet de s’orienter adéquatement dans un domaine : voir quels sont les instruments conceptuels à disposition et à quels problèmes potentiels ils s’attachent. Attention par « philosophie », il faut entendre non pas une discipline instituée mais une tâche systématique que toute science porte en elle (et que plusieurs agents peuvent bien entendu endosser, indépendamment de leur formation disciplinaire). Et la question qu’il s’agit de poser en priorité (c’est-à-dire : de poser encore, de maintenir, de relancer) : Qu’est-ce qu’une image / représentation iconique (représentation par l’image) ? (I, §6), quels types d’objets rencontrent les conditions définitoires minimales de l’image ? Quels types d’expérience définissent les limites de ce qu’on peut appeler l’expérience iconique ? Une fois les contours dessinés, la carte continue à nous offrir une infinité de positions possibles entre lesquelles nous pouvons nous déplacer. [less ▲]

Detailed reference viewed: 16 (0 ULg)
See detailCharacterization of FRD3, a zinc and iron homeostasis actor, in Arabidopsis
Scheepers, Maxime ULg; Charlier, Jean-Benoit; Spielmann, Julien ULg et al

Poster (2016, May 13)

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See detailLe concours d’habitations ouvrières du Tribouillet (1930) et la réception des théories de l’habitation minimum à Liège
Charlier, Sébastien ULg

Conference (2016, May 13)

En 1930, Liège et Anvers accueillent chacune une vaste exposition célébrant le centenaire de l’indépendance de la Belgique. À Liège, probablement sous l’impulsion de Victor Bourgeois, un concours ... [more ▼]

En 1930, Liège et Anvers accueillent chacune une vaste exposition célébrant le centenaire de l’indépendance de la Belgique. À Liège, probablement sous l’impulsion de Victor Bourgeois, un concours d’habitations ouvrières est organisé sur les hauteurs de la ville, dans le quartier du Tribouillet. L’événement est un moment fort de l’histoire de l’architecture à Liège, ville industrielle belge de seconde importance. Si l’essentiel du site, urbanisé selon le modèle de la cité-jardin, est occupé par des petites habitations unifamiliales sans innovations particulières, un secteur est réservé aux maisons dites « minimum ». Il y a, dans le chef des organisateurs, une volonté manifeste de s’inscrire dans la continuité des réflexions du CIAM 2 de Francfort et de faire écho aux « Journées de l’habitation minimum » présentées à Bruxelles en 1930. Des personnalités reconnues pour leur expertise en matière de logement public comme Victor Bourgeois, Louis Herman de Koninck, Fernand Bodson ou encore Joseph Moutschen sont invitées à présenter leurs conceptions du logement « moderne ». Notre contribution se propose, d’abord, de situer ces interventions dans la généalogie de la production de ces architectes en soulignant leurs particularités spatiales, constructives et esthétiques. Il s’agit également de montrer comment ces « phénomènes » ont influé sur la pratique locale, en particulier sur les jeunes architectes fascinés par les modèles internationaux, et comment ils furent reçus tant dans la maîtrise d’ouvrage privée que publique. Notre intervention montrera également en quoi l’expérience de 1930 fut un moment charnière dans les politiques locales de logement public. Car si l’historiographie reconnaît la portée du concours du Tribouillet, en tant que phénomène de spectacularisation locale et nationale des concepts du Mouvement moderne, elle oublie que l’événement marqua provisoirement la fin du recours au modèle de la cité-jardin à Liège. Écrasées par des charges de plus en plus lourdes, les sociétés de logement réinvestissent les centres urbains abandonnant le modèle de la petite maison unifamiliale au profit de l’immeuble à appartements. Une attention particulière sera également apportée au contexte culturel et au vif débat que connaît l’architecture à Liège dans l’entre-deux-guerres à travers l’analyse des revues locales et des expositions qu’elles organisèrent pour diffuser leurs modèles. [less ▲]

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See detailAnalyse multifractale de la vitesse de divergence de séries d'ondelettes
Esser, Céline ULg

Scientific conference (2016, May 13)

Detailed reference viewed: 8 (0 ULg)