Last 7 days
Bookmark and Share    
Full Text
Peer Reviewed
See detailAbility of Tuta absoluta (Lepidoptera: Gelechiidae) to develop on alternative host plant species
Bawin, Thomas ULg; Dujeu, David; De Backer, Lara ULg et al

in Canadian Entomologist (2016), 148(4), 434-442

The tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is a widespread devastating pest reported to develop on economically important solanaceous crops. The characterization of its host ... [more ▼]

The tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is a widespread devastating pest reported to develop on economically important solanaceous crops. The characterization of its host range could help to understand and prevent the dispersion behavior of the insect in the environment. In this study, the ability of T. absoluta to develop on 12 cultivated or non-cultivated plants including Solanaceae, Chenopodiaceae, Convolvulaceae, Fabaceae and Malvaceae species under laboratory conditions was assessed. For each plant species, we monitored the development times of immature stages, survival, sex ratios and adult fecundity rates. All the 6 tested non-solanaceous plants, including Chenopodium, Convolvulus and Malva species, were not able to sustain (i.e. allow growth and development) T. absoluta larvae. Among Solanaceae, Solanum species were the most suitable host plants for the pest, but others could be opportunistically colonized with fewer incidences. T. absoluta appears to be strongly related to solanaceous plants which would predominantly support self-sustaining field populations. Preventing crop infestation by removing potential host plants in the immediate field vicinity and culture rotations with non-solanaceous crops is of primary importance. [less ▲]

Detailed reference viewed: 69 (14 ULg)
Full Text
Peer Reviewed
See detailAspects fonciers de l'exil des religieux français en Belgique (1901-1914)
Murez, Jean-Baptiste ULg

Conference (2016, August 19)

Detailed reference viewed: 27 (1 ULg)
See detailLes enquêtes de terrain du Musée de la Vie wallonne : Un outil au service de la collecte de la mémoire, des savoirs et savoir-faire régionaux
Postula, Jean-Louis ULg

Conference (2016, August 19)

Débutées dans les années 1920, la réalisation de reportages sur le terrain puis la diffusion régulière des résultats de ces recherches ont été pendant longtemps l’un des traits distinctifs de la fonction ... [more ▼]

Débutées dans les années 1920, la réalisation de reportages sur le terrain puis la diffusion régulière des résultats de ces recherches ont été pendant longtemps l’un des traits distinctifs de la fonction scientifique mise en œuvre au Musée de la Vie wallonne. Jusqu’à la fin des années 1980 environ, les activités du Service des enquêtes ont permis au Musée de devenir le conservatoire d’une collection unique en son genre de documents d’archives multimédia – photographies, films et sons. La rénovation du Musée à partir de 2004, assortie de la réorientation de son projet muséal vers le modèle du « musée de société », a été l’occasion d’investir à nouveau du temps et des moyens dans la relance de cette riche tradition d’enquêtes ethnographiques. Grâce à de nombreux exemples, cette communication ambitionne de montrer l’évolution des terrains d’enquêtes du Musée, qui privilégie désormais l’exploration de nouvelles thématiques liées aux enjeux contemporains de nos sociétés urbaines, industrielles et post-industrielles. Oscillant entre continuité et renouvellement, les enquêtes du Musée de la Vie wallonne permettent à l’institution de se profiler comme un contributeur influent à la préservation du patrimoine culturel immatériel de notre région. [less ▲]

Detailed reference viewed: 19 (0 ULg)
See detailAggiornamento historiographique sur Godefroid Kurth (XIXème siècle-2016)
Genin, Vincent ULg

Conference (2016, August 19)

Detailed reference viewed: 15 (2 ULg)
Full Text
Peer Reviewed
See detailTwo-Parameter Kinematic Approach for Shear Strength of Deep Concrete Beams with Internal FRP Reinforcement
Mihaylov, Boyan ULg

in Journal of Composites for Construction (2016), DOI: 10.1061/(ASCE)CC.1943-5614 .0000747

Tests of deep concrete beams with internal fiber-reinforced polymer (FRP) reinforcement have shown that such members can exhibit lower shear strength than members with conventional steel reinforcement. To ... [more ▼]

Tests of deep concrete beams with internal fiber-reinforced polymer (FRP) reinforcement have shown that such members can exhibit lower shear strength than members with conventional steel reinforcement. To model this effect, the current paper proposes an approach based on a two-parameter kinematic theory (2PKT) for conventional deep beams. The 2PKT is built on a kinematic model with two degrees of freedom that describes the deformation patterns of cracked beams. Using this theory shows that large strains in FRP longitudinal reinforcement result in reduced shear resistance of the critical loading zones (CLZ) of deep beams. The original 2PKT is therefore modified by introducing a reduction factor for the shear carried by the CLZ. The extended 2PKT approach is then applied to a database of 39 tests of FRP-reinforced deep beams from the literature, resulting in an average shear strength experimental-to-predicted ratio of 1.06 and a coefficient of variation of 18.3%. The results show that the 2PKT adequately captures the effects of the stiffness of the reinforcement, section depth, concrete strength, and shear-span-to-depth ratio on the shear strength of FRP-reinforced deep beams. [less ▲]

Detailed reference viewed: 9 (3 ULg)
Full Text
See detailBIG NOISE - Un orchestre belge- Un nouvel hommage, en live, au JAZZ style NEW ORLEANS
Sacré, Robert ULg

E-print/Working paper (2016)

Compte Rendu du 3è opus du groupe BIG NOISE, un orchestre belge qui remet à l'honneur le jazz traditionnel style NEW ORLEANS ( album IGLOO RECORDS)

Detailed reference viewed: 4 (0 ULg)
See detailLe projet EpistolART à la lumière de certaines lettres évoquant Léonard de Vinci
Delfosse, Annick ULg; Fagnart, Laure ULg

Conference (2016, August 19)

Le projet EpistolART – dont nous sommes co-promotrices, avec Paola Moreno et Dominique Allart – explore le matériau épistolaire artistique de la première modernité. Dans ce cadre, le "Carteggio inedito ... [more ▼]

Le projet EpistolART – dont nous sommes co-promotrices, avec Paola Moreno et Dominique Allart – explore le matériau épistolaire artistique de la première modernité. Dans ce cadre, le "Carteggio inedito d’artisti dei secoli XIV, XV, XVI" que Johann Wilhelm Gaye a publié en 1839-1840 constitue l’un de nos corpus privilégiés. Méritoire, le travail de Gaye n’en demeure pas moins dépassé : aussi l’équipe EpistolART a-t-elle entrepris d'éditer à nouveaux frais ce corpus, en suivant les critères de la philologie, de la codicologie et de la paléographie moderne, et de reverser cette édition dans une base de données en ligne. Durant notre intervention, nous voudrions d’abord vous présenter la base de données EpistolART (travail éditorial, heuristique, conception de la base de données) puis nous arrêter sur quelques lettres évoquant Léonard de Vinci dont les membres du projet EpistolART proposent une nouvelle édition. Ces missives constituent des documents extrêmement précieux pour écrire l’histoire des relations entre le maître florentin et la France, spécialement avec le roi Louis XII, qui appelle l’artiste à son service en 1506. Si les historiens qui se sont penchés sur la vie et l’œuvre de Léonard de Vinci connaissent ces correspondances, rares sont ceux qui ont recouru aux documents épistolaires originaux. Or, ce n’est qu’au départ d’un texte sûr, appréhendé tant dans sa matérialité que dans ses contenus, que peuvent se déployer des analyses scientifiquement fondées. [less ▲]

Detailed reference viewed: 23 (1 ULg)
Full Text
Peer Reviewed
See detailIncorporation of iron and organic matter into young Antarctic sea ice during its initial growth stages
Janssens, Julie; Meiners, Klaus M.; Tison, Jean-Louis et al

in Elementa: Science of the Anthropocene (2016), 4(1), 000123

This study reports concentrations of iron (Fe) and organic matter in young Antarctic pack ice and during its initial growth stages in situ. Although the importance of sea ice as an Fe reservoir for ... [more ▼]

This study reports concentrations of iron (Fe) and organic matter in young Antarctic pack ice and during its initial growth stages in situ. Although the importance of sea ice as an Fe reservoir for oceanic waters of the Southern Ocean has been clearly established, the processes leading to the enrichment of Fe in sea ice have yet to be investigated and quantified. We conducted two in situ sea-ice growth experiments during a winter cruise in the Weddell Sea. Our aim was to improve the understanding of the processes responsible for the accumulation of dissolved Fe (DFe) and particulate Fe (PFe) in sea ice, and of particulate organic carbon and nitrogen, dissolved organic carbon, extracellular polymeric substances, inorganic macro-nutrients (silicic acid, nitrate and nitrite, phosphate and ammonium), chlorophyll a and bacteria. Enrichment indices, calculated for natural young ice and ice newly formed in situ, indicate that during Antarctic winter all of the measured forms of particulate matter were enriched in sea ice compared to underlying seawater, and that enrichment started from the initial stages of sea-ice formation. Some dissolved material (DFe and ammonium) was also enriched in the ice but at lower enrichment indices than the particulate phase, suggesting that size is a key factor for the incorporation of impurities in sea ice. Low chlorophyll a concentrations and the fit of the macro-nutrients (with the exception of ammonium) with their theoretical dilution lines indicated low biological activity in the ice. From these and additional results we conclude that physical processes are the dominant mechanisms leading to the enrichment of DFe, PFe, organic matter and bacteria in young sea ice, and that PFe and DFe are decoupled during sea-ice formation. Our study thus provides unique quantitative insight into the initial incorporation of impurities, in particular DFe and PFe, into Antarctic sea ice. [less ▲]

Detailed reference viewed: 22 (1 ULg)
Full Text
Peer Reviewed
See detailModel Sensitivity Studies of the Decrease in Atmospheric Carbon Tetrachloride
Chipperfield, M. P.; Liang, Q.; Rigby, M. et al

in Atmospheric Chemistry & Physics Discussions (2016), 2016

Carbon tetrachloride is an ozone-depleting substance, which is controlled by the Montreal Protocol and for which the atmospheric abundance is decreasing. However, the current observed rate of this ... [more ▼]

Carbon tetrachloride is an ozone-depleting substance, which is controlled by the Montreal Protocol and for which the atmospheric abundance is decreasing. However, the current observed rate of this decrease is known to be slower than expected based on reported CCl4 emissions and its estimated overall atmospheric lifetime. Here we use a three-dimensional (3-D) chemical transport model to investigate the impact on its predicted decay of uncertainties in the rates at which CCl4 is removed from the atmosphere by photolysis, by ocean uptake and by degradation in soils. The largest sink is atmospheric photolysis (76% of total) but a reported 10% uncertainty in its combined photolysis cross-section and quantum yield has only a modest impact on the modelled rate of CCl4 decay. This is partly due to the limiting effect of the rate of transport of CCl4 from the main tropospheric reservoir to the stratosphere where photolytic loss occurs. The model suggests large interannual variability in the magnitude of this stratospheric photolysis sink caused by variations in transport. The impact of uncertainty in the minor soil sink (9% of total) is also relatively small. In contrast, the model shows that uncertainty in ocean loss (15% of total) has the largest impact on modelled CCl4 decay due to its sizeable contribution to CCl4 loss and large uncertainty range (157 to 313 years). With an assumed CCl4 emission rate of 39 Gg/yr, the reference simulation with best estimate of loss processes still underestimates the observed CCl4 (overestimates the decay) over the past two decades but to a smaller extent than previous studies. Changes to the rate of CCl4 loss processes, in line with known uncertainties, could bring the model into agreement with in situ surface and remote-sensing measurements, as could an increase in emissions to around 45 Gg/yr. Further progress in constraining the CCl4 budget is partly limited by systematic biases between observational datasets. For example, surface observations from the NOAA network are larger than from the AGAGE network but have shown a steeper decreasing trend over the past two decades. These differences imply a difference in emissions which is significant relative to uncertainties in the magnitudes of the CCl4 sinks. [less ▲]

Detailed reference viewed: 17 (0 ULg)
Full Text
See detailCanine idiopathic pulmonary fibrosis : improvement of the phenotype characterization and search for biomarkers and for etiologic agents
Roels, Elodie ULg

Doctoral thesis (2016)

Canine idiopathic pulmonary fibrosis (CIPF) is a progressive parenchymal lung disease of unknown origin, mainly described in old-aged West Highland white terriers (WHWTs). It is characterized by exercise ... [more ▼]

Canine idiopathic pulmonary fibrosis (CIPF) is a progressive parenchymal lung disease of unknown origin, mainly described in old-aged West Highland white terriers (WHWTs). It is characterized by exercise intolerance, cough and dyspnoea/tachypnea with a progressive deterioration until death from respiratory insufficiency. CIPF shares clinical features with human idiopathic pulmonary fibrosis (IPF), while tomodensitometric and histopathological findings do not appear to be exactly the same. Over the past 10 years, several studies have been performed to improve our knowledge about CIPF. However, this disease is still misunderstood and clinicians are dealing with several challenges including the absence of clinical or biological markers for estimating the presence, severity or progression of the disease and related comorbidities such as pulmonary hypertension, the absence of etiologic agent, and the absence of targeted therapy. Consequently, the aims of the present project were (1) to investigate whether high-resolution computed tomography (HRCT) of the lungs obtained under sedation can be used for the diagnosis and for the follow-up of the disease, (2) to study a new echocardiographic parameter for the diagnosis of precapillary pulmonary hypertension induced by CIPF, (3) to study the potential roles of 2 chemokines of interest, CCL2 and CXCL8, as biomarkers of fibrosis and as actors in the pathogenesis of the disease, (4) to determine breed variation of basal blood concentrations of the same chemokines, vascular endothelial growth factor (VEGF), and serotonin, and (5) to search for the presence of herpesvirus as a possible etiologic agent. [less ▲]

Detailed reference viewed: 16 (3 ULg)
See detailA Comparison between four Techniques to Measure Cardiac Output
Pironet, Antoine ULg; Dauby, Pierre ULg; Chase, J. Geoffrey et al

Poster (2016, August 17)

Detailed reference viewed: 17 (2 ULg)
Full Text
Peer Reviewed
See detailA Comparison between four Techniques to Measure Cardiac Output
Pironet, Antoine ULg; Dauby, Pierre ULg; Chase, J. Geoffrey et al

in Proceedings of the 38th International Conference of the IEEE Engineering in Medicine and Biology Society (2016, August 17)

Cardiac output is an important variable when monitoring hemodynamic status. In particular, changes in cardiac output represent the goal of several circulatory management therapies. Unfortunately, cardiac ... [more ▼]

Cardiac output is an important variable when monitoring hemodynamic status. In particular, changes in cardiac output represent the goal of several circulatory management therapies. Unfortunately, cardiac output is very difficult to estimate, either in experimental or clinical settings. The goal of this work is to compare four techniques to measure cardiac output: pressure-volume catheter, aortic flow probe, thermodilution, and the PiCCO monitor. These four techniques were simultaneously used during experiments of fluid and endotoxin administration on 7 pigs. Findings show that, first, each individual technique is precise, with a relative coefficient of repeatability lower than 7 %. Second, 1 cardiac output estimate provided by any technique relates poorly to the estimates from the other 3, even if there is only small bias between the techniques. Third, changes in cardiac output detected by one technique are only detected by the others in 62 to 100 % of cases. This study confirms the difficulty of obtaining a reliable clinical cardiac output measurement. Therefore, several measurements using different techniques should be performed, if possible, and all such should be treated with caution. [less ▲]

Detailed reference viewed: 15 (1 ULg)
Full Text
Peer Reviewed
See detailÉmotion, ipséité, liberté. Réflexions à propos des fondements de la théorie sartrienne des émotions
Recchia, Fabio ULg

in Bulletin d'Analyse Phénoménologique (2016), 12(5), 1-23

Entretenue durant la drôle de guerre, la correspondance épistolaire entre De Beauvoir et Sartre révèle une insatisfaction de ce dernier à l'égard de sa théorie des émotions. Celle-ci manquerait en effet ... [more ▼]

Entretenue durant la drôle de guerre, la correspondance épistolaire entre De Beauvoir et Sartre révèle une insatisfaction de ce dernier à l'égard de sa théorie des émotions. Celle-ci manquerait en effet de fondements solides. Répondant à ce constat, nous tenterons de dégager les fondations de cette théorie de manière à expliciter ses enjeux. Nous replacerons, pour ce faire, l'Esquisse d'une théorie des émotions dans la perspective plus générale de la théorie de l'intentionnalité du premier Sartre. De la sorte nous montrerons, d'une part, comment ce texte renouvelle significativement la catégorie de l'action en concevant l'émotion comme une activité ; et nous examinerons, d'autre part, l'interaction existant entre l¿émotion et l'ipséité de la conscience. Cette discussion dévoilera ainsi l'intentionnalité émotive comme une passion active reconduisant au fondement de la conscience qui est sa liberté personnelle. [less ▲]

Detailed reference viewed: 26 (5 ULg)
See detailReformulations of nonlinear binary optimization problems
Crama, Yves ULg

Scientific conference (2016, August 17)

Detailed reference viewed: 11 (0 ULg)
Full Text
See detailThe Chemistry of New Garlic-Derived Organosulfur Compounds and the Molecular Basis of Olfaction »
Dethier, Bérénice ULg

Doctoral thesis (2016)

Garlic is a very popular condiment that has been used around the world for centuries. It is also a source of a remarkably extensive range of organosulfur compounds, whose chemistry is the focus of this ... [more ▼]

Garlic is a very popular condiment that has been used around the world for centuries. It is also a source of a remarkably extensive range of organosulfur compounds, whose chemistry is the focus of this thesis. The central reaction in formation of these compounds is the enzymatic cleavage of alk(en)yl cysteine sulfoxides by alliinases, which leads to sulfenic acids. The latter can then undergo condensation and rearrangement into various organosulfur compounds. Three aspects of the chemistry of garlic have been investigated in this thesis. First, little studied, minor organosulfur compounds in extracts of freshly chopped garlic were studied. These higher molecular weight compounds (MW 150–550) can be conveniently studied using state-of-the-art Liquid Chromatography-Mass Spectrometry (LC-MS) and Direct Analysis in Real Time-Mass Spectrometry (DART-MS) techniques. Novel garlic-derived compounds were studied and the structure of one representative compound containing a five-membered thiolane ring, ajothiolane, was determined by spectroscopic methods, using synthetic analogues as spectroscopic standards. The fate of compounds in a garlic extract over time was also studied, since the new, higher mass sulfur compounds are slowly formed by rearrangement of smaller metabolites a few days after maceration of the garlic. A second part of this thesis provides hands-on methods for the analysis and preparation of key garlic metabolites. The isolation and/or synthesis of alliin, alliinase and vinyldithiins have been optimized, and are proposed as turnkey procedures for future work. Finally, in an effort to explain the unique odor of garlic-related thiols and sulfides (in garlic breath, sweat, etc.), the interactions between odorants and olfactory receptors have been studied. Work described in this thesis contributed to this larger project by designing and synthesizing model macrocyclic odorants to resolve the mechanism of olfaction at the receptor level. The conclusions, arguing against the plausibility of the so-called “vibration theory of olfaction”, have been published as a foundation for future work on olfactory detection of thiols and other sulfur-containing compounds. [less ▲]

Detailed reference viewed: 38 (4 ULg)
Full Text
Peer Reviewed
See detailUse of slow-release plant infochemicals to control aphids: a first investigation in a Belgian wheat field
Zhou, Haibo; Chen, Longsheng; Liu, Yong et al

in Scientific Reports (2016)

Using infochemicals to develop a push–pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow ... [more ▼]

Using infochemicals to develop a push–pull strategy in pest control is a potential way to promote sustainable crop production. Infochemicals from plant essential oils were mixed with paraffin oil for slow release in field experiments on wheat to control the population density of cereal aphids and to enhance their natural enemies. (Z)-3-Hexenol (Z3H) attracted Metopolophum dirhodum and Sitobion avenae, the predominant species on wheat in Belgium, and may be a useful infochemical for aphid control by attracting aphids away from field plots. Release of (E)-β-farnesene (EBF) or a garlic extract (GE) led to a significant decrease in the abundance of wheat aphids. The main natural enemies of cereal aphids found were lacewings (47.8%), hoverflies (39.4%), and ladybirds (12.8%). Ladybird abundance varied little before the end of the wheat-growing season. Our results suggest that these chemicals can form the basis of a “push–pull” strategy for aphid biological control, with GE and EBF acting as a pestand beneficial-pulling stimulus and Z3H for aphid pulling. [less ▲]

Detailed reference viewed: 22 (5 ULg)