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See detailAcetylene (C2H2) and hydrogen cyanide (HCN) from IASI satellite observations: global distributions, validation, and comparison with model
Duflot, V.; Wespes, C.; Clarisse, L. et al

in Atmospheric Chemistry & Physics Discussions (2015), 15(10), 14357--14401

We present global distributions of C2H2 and HCN total columns derived from the Infrared Atmospheric Sounding Interferometer (IASI). These distributions are obtained with a fast method allowing to retrieve ... [more ▼]

We present global distributions of C2H2 and HCN total columns derived from the Infrared Atmospheric Sounding Interferometer (IASI). These distributions are obtained with a fast method allowing to retrieve C2H2 abundance globally with a 5% precision and HCN abundance in the tropical (subtropical) belt with a 10% (30%) precision. IASI data are compared for validation purposes with ground-based Fourier Transform Infrared (FTIR) spectrometer measurements at four selected stations. We show that there is an overall agreement between the ground-based and space measurements. Global C2H2 and subtropical HCN abundances retrieved from IASI spectra show the expected seasonality linked to variations in the anthropogenic emissions and seasonal biomass burning activity, as well as exceptional events, and are in good agreement with previous spaceborne studies. IASI measurements are also compared to the distributions from the Model for Ozone and Related Chemical Tracers, version 4 (MOZART- 4). Seasonal cycles observed from satellite data are reasonably well reproduced by the model. However, the model seems to overestimate (underestimate) anthropogenic (biomass burning) emissions and a negative global mean bias of 1% (16 %) of the model relative to the satellite observations was found for C2H2 (HCN). [less ▲]

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See detailAnatomy of the pelvis re-designed
Bonnet, Pierre ULg

Conference (2015, May 21)

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See detailInvestigation of the consistency of the recent CH4 increase derived from NDACC-FTIR, ACE-FTS and GEOS-Chem
Bader, Whitney ULg; Conway, Stephanie; Strong, Kim et al

Conference (2015, May 21)

We present an update on the status of the recent methane increase study based on six FTIR ground-based sites, ACE-FTS satellite occultations and GEOS-Chem simulation.

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See detail"Tell me about Self." Clarté de soi et souvenirs définissant le soi: Particularités du self chez des individus souffrant d'un trouble de l'humeur
Boulanger, Marie ULg; Wagener, Aurélie ULg; Blairy, Sylvie ULg

Poster (2015, May 21)

The present study focusses on a particular kind of autobiographical memories called self-defining memories (SDMs). SDMs are highly pertinent for self-building because they help to define in the most ... [more ▼]

The present study focusses on a particular kind of autobiographical memories called self-defining memories (SDMs). SDMs are highly pertinent for self-building because they help to define in the most clearly way our perception of ourselves. If literature showed that depressed and bipolar patients suffer from autobiographical memory (AM) disturbances, SDMs have not been studied a lot since yet in these two disorders. Then, the present study pursues two main aims: (1) to assess SDM’s characteristics and (2) to assess the relationship between the ability to retrieve SDM’s and self-concept clarity. To reach our objective, 17 depressed and 16 bipolar patients are compared to 17 healthy subjects. Participants are asked to complete SDMs procedure that is recalling six important events which happened in their life. These SDMs are assessed on four variables: specificity, impact, valence, meaning making, contain. Self-concept clarity and mood are also assessed. Preliminary results do not highlight difference between our groups on specificity. Marginal effects appear for meaning making with healthy subjects recalling more meaning making events. Results show that depressed patients present a mood congruence. The final results will be presented during the convention, as data-collection is on-going and will end in April. Experimental and clinical implications of our results will be discussed. [less ▲]

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See detailOn the use of the transmission disequilibrium test to detect pseudo-autosomal variants affecting traits with sex-limited expression
Elansary, Mahmoud ULg; Stinckens, Anneleen; Ahariz, Naïma ULg et al

in Animal Genetics (2015)

We herein describe the realization of a genome-wide association study for scrotal hernia and cryptorchidism in Norwegian and Belgian commercial pig populations. We have used the transmission ... [more ▼]

We herein describe the realization of a genome-wide association study for scrotal hernia and cryptorchidism in Norwegian and Belgian commercial pig populations. We have used the transmission disequilibrium test to avoid spurious associations due to population stratification. By doing so, we obtained genome-wide significant signals for both diseases with SNPs located in the pseudo-autosomal region in the vicinity of the pseudo-autosomal boundary. By further analyzing these signals, we demonstrate that the observed transmission disequilibria are artifactual. We determine that transmission bias at pseudo-autosomal markers will occur (i) when analyzing traits with sex-limited expression and (ii) when the allelic frequencies at the marker locus differ between X and Y chromosomes. We show that the bias is due to the fact that (i) sires will preferentially transmit the allele enriched on the Y (respectively X) chromosome to affected sons (respectively daughters) and (ii) dams will appear to preferentially transmit the allele enriched on the Y (respectively X) to affected sons (respectively daughters), as offspring inheriting the other allele are more likely to be non-informative. We define the conditions to mitigate these issues, namely by (i) extracting information from maternal meiosis only and (ii) ignoring trios for which sire and dam have the same heterozygous genotype. We show that by applying these rules to scrotal hernia and cryptorchidism, the pseudo-autosomal signals disappear, confirming their spurious nature. [less ▲]

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See detailCritical analysis and alternative treatment of Type Ia Supernovae data
Hauret, Clémentine ULg

Conference (2015, May 20)

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See detailLa coopération Sud-Sud au sein des BRICS ; un nouveau paradigme d’aide au développement? Le cas du Brésil en Mozambique
Cusson, Gabrielle ULg

Conference (2015, May 20)

L’émergence et l’affirmation de nouvelles puissances dites du « Sud », dont celles des BRICS, ont donné un nouveau souffle à la coopération Sud-Sud (CSS), et ce spécialement en Afrique. Ces émergents ... [more ▼]

L’émergence et l’affirmation de nouvelles puissances dites du « Sud », dont celles des BRICS, ont donné un nouveau souffle à la coopération Sud-Sud (CSS), et ce spécialement en Afrique. Ces émergents jouissent d’une marge de manœuvre politique et économique grandissante qui leur permet de multiplier les partenariats Sud-Sud, de contribuer financièrement à la coopération au développement et d’instaurer de nouvelles structures d’institutionnalisation de CSS. La stratégie de CSS des BRICS se veut différente du modèle traditionnel de coopération Nord-Sud (CNS) ; elle s’appuie sur des principes de solidarité, offre une aide sans condition, se base sur des relations horizontales permettant des bénéfices mutuels pour les partenaires. Cependant, la CSS engagée par les BRICS n’est pas exempte de retombées politiques, diplomatiques ou commerciales à leur égard. Dans ce contexte, il est valable de se questionner à savoir si une politique de coopération au développement déployée par une puissance émergente peut être désintéressée et s’il est possible d’établir des relations d’égal à égal alors qu’elle se développe dans un cadre de rapports entre un donateur et un récepteur ? Cette présentation tentera de déterminer si le modèle de CSS soutenu par les BRICS s’inscrit dans un nouveau paradigme pour repenser l’efficacité de l’aide au développement en Afrique ou s’il reproduit la structure d’aide traditionnelle du modèle de CNS. Pour ce faire, nous étudierons le cas de la pénétration brésilienne au Mozambique, soit son implication technique et financière au développement de l’exploitation de certaines cultures à des fins de production de biocarburants. [less ▲]

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See detailRecent results derived from regular ground-based FTIR observations at the Jungfraujoch and other NDACC stations
Mahieu, Emmanuel ULg; Bader, Whitney ULg; Franco, Bruno ULg

Scientific conference (2015, May 20)

We present an overview of the recent results derived from the observational program for the long-term monitoring of the Earth's atmosphere from the Jungfraujoch station, including comparison with data ... [more ▼]

We present an overview of the recent results derived from the observational program for the long-term monitoring of the Earth's atmosphere from the Jungfraujoch station, including comparison with data from the ACE-FTS satellite instrument and other NDACC stations. [less ▲]

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See detailLes circuits-courts en alimentation comme réponse au défi climatique
Ozer, Pierre ULg

Conference (2015, May 20)

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See detailPredicting the non-linear shear behaviour of deep beams based on a two-parameter kinematic model
Mihaylov, Boyan ULg

in Concrete - Innovation and Design, fib Symposium Proceedings, Copenhagen 18 to 20 May 2015 (2015, May 20)

Deep beams are often used as transfer girders in high rise buildings to support heavy loads from discontinuous columns or shear walls. Several buildings with such transfer girders were affected by the ... [more ▼]

Deep beams are often used as transfer girders in high rise buildings to support heavy loads from discontinuous columns or shear walls. Several buildings with such transfer girders were affected by the February 2011 earthquake in Christchurch, New Zealand, which produced very large vertical accelerations and overloaded the transfer girders. One of the buildings had to be stabilized urgently in the hours after the earthquake while others sustained significant damage. The structures which remained standing were those capable of redistributing the forces from the damaged transfer girders to less damaged structural members. The extent of such force redistribution, and therefore the ability of the structure to survive extreme events, depends in part on the displacement capacity and post-peak behaviour of the transfer girders. For this reason, the evaluation of structures with deep transfer girders under extreme loading requires accurate models for predicting the complete non-linear response of the girders. As deep beams usually fail in a brittle manner due to shear, predicting their non-linear behaviour represents a challenging problem even when sophisticated non-linear finite element models are used. This paper will discuss a simpler alternative approach based on a kinematic model for deep beams. The kinematic model describes the deformation patterns of the beam with the help of two degrees of freedom: the average strain along the flexural reinforcement from support to support, and the transverse displacement in the critical zones in the vicinity of the applied loads (critical loading zones). The model assumes that much of the deformations concentrate along a critical diagonal crack which widens and slips as the deflections of the member increase. The equations of the kinematic model are combined with equilibrium equations and constitutive relationships for the load-resisting mechanisms across the critical crack. These mechanisms include diagonal compression in the critical loading zones, aggregate interlock, tension in the stirrups crossing the crack, and dowel action of the longitudinal reinforcement. The complete set of equations is solved iteratively in order to compute the pre- and post- peak response of deep beams. This approach is validated with the help of tests of deep beams. The model will be used to draw conclusions on the effect of the properties of deep beams on their non-linear behaviour. [less ▲]

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See detailStudy of essential oil activity on Curvularia sp. a rice leaf spot pathogen in Madagascar
Mamiharisoa Razanakoto, Léa ULg; Parisi, Olivier ULg; Massart, Sébastien ULg et al

Poster (2015, May 19)

Rice leaf spot have been observed on many fields during survey of rice diseases in three regions in Madagascar. Curvularia sp. was the most frequently isolated pathogen from the most severe diseased ... [more ▼]

Rice leaf spot have been observed on many fields during survey of rice diseases in three regions in Madagascar. Curvularia sp. was the most frequently isolated pathogen from the most severe diseased samples. This pathogen has been reported worldwide to cause important losses. Then in this work, we study the possibility to develop an alternative method to control Curvularia sp. Plants or plant extracts have been traditionally used to control human and plant diseases. Nowadays, the problem of residues of phytopharmaceutical products, reinforce the need for research on the development of natural plant extracts to control plant diseases. Madagascar has many endemic plants of interest. The antimicrobial properties of essential oils from Malagasy aromatic plants were evaluated. The main steps of this study are (i) the in-vitro screening of 39 Malagasy essential oils to control this pathogen, (ii) the evaluation of the phytotoxicity (on rice plants) of the efficient essential oils and (iii) the in vivo test of the activity of these non phytotoxic essential oils on Curvularia sp. on rice seedlings. The activity of essentials oils on Curvularia sp. has been tested in vitro during a microscale ELISA plate bioassay using optical density for a rapid evaluation of the biofungicidal activity of the extracts. Essential oils that showed interesting antifungal effect on this pathogen were tested for their phytotoxicity on rice plants. Briefly, one to two drop(s) of essential oils were applied on 3 leaves leaves of three weeks rice seedling. Six essential oils over the 39 tested showed an interesting antifungal activity with a percentage of growth inhibition greater than 70%. Three essential oils tested were phytotoxic as they induced necrotic spots on rice leaves after 48 h. Among three essential oils left, one of them showed an important effect when applied on rice seedling inoculated with a conidial suspension of Curvularia sp. These results confirmed that some essential oils present an antifungal activity. And even some of them are phytotoxic on rice plants, some essential oils show interesting potential to be an alternative method against rice diseases. [less ▲]

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See detailEfficiency of pheromone-based formulations against phytophagous pests
Fassotte, Bérénice ULg; Vandereycken, Axel ULg; Chevalier Mendes Lopes, Thomas ULg et al

Conference (2015, May 19)

Innovative integrated pest management methods are needed to overcome market withdrawal of synthetic pesticides. Therefore, the identification of environment-friendly bio-products carrying direct or ... [more ▼]

Innovative integrated pest management methods are needed to overcome market withdrawal of synthetic pesticides. Therefore, the identification of environment-friendly bio-products carrying direct or indirect biocide activity is one promising alternative option. Our researches focus on the identification of appropriate formulations releasing volatile organic compounds that are attractant for natural enemies of insect pests. However, the elaboration of slow-release devices that ensure stable and controlled release of active volatile compounds is quite challenging. Here, we developed a formulation based on E-β-farnesene and (-)-β-caryophyllene, these two semiochemicals having strong attractive potential on aphid natural enemies including lady beetles and hoverflies. Both compounds were encapsulated together in alginate gel beads. The blend efficiency was first evaluated through laboratory assays, and then in wheat and broad bean fields, by considering the abundance and diversity of aphids and their natural enemies. [less ▲]

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See detailTuta absoluta (Lepidoptera: Gelechiidae) development on wild and cultivated plant species
Bawin, Thomas ULg; Dujeu, David ULg; Fagan, Maud ULg et al

Conference (2015, May 19)

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread invasive species damaging economically important cultivated solanaceous crop plants, including tomatoes and potatoes. Little ... [more ▼]

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread invasive species damaging economically important cultivated solanaceous crop plants, including tomatoes and potatoes. Little is known about the ability of this microlepidoptera to encounter and develop on alternative wild and agricultural plant species. These plants could provide refuges and have to be identified for more efficient integrated management strategies. In the present study, we assessed under laboratory conditions the ability of T. absoluta to develop on such plant species referred as potential hosts in the literature, including Solanaceae, Chenopodiaceae, Convolvulaceae, Fabaceae, and Malvaceae. For each plant species, fitness tests were performed in Petri dishes by isolating single individuals with excised leaf. We found that Solanum species allowed higher larval survivability and shorter development time (from egg to adult emergency) compared to the other plants. Non-solanaceous plants were not able to sustain T. absoluta larvae. Two choice behavioral assays performed in flying tunnels revealed that adult distribution and female oviposition did not differ between Solanum species, which were preferred to other tested solanaceous plants. These results appeared to be consistent with survival rates and development times. Because larval survivability depends on the female’s oviposition choice, the hypothesis that host plant choice is influenced by plant volatile organic compounds has to be tested. Volatile organic compounds released by solanaceous plants were trapped using a dynamic collection system, and analyzed by GC-MS. Solanum volatile profiles showed similarities, and were presenting quantitative and qualitative differences with the other tested solanaceous plants, providing some explanations in the observed behavioral discrimination. Further electrophysiological and behavioral assays are required to confirm the effect of specific chemicals on the choice of the oviposition site in T. absoluta. It can be concluded that Solanum species are the more suitable hosts for T. absoluta development. Other solanaceous plant species could be opportunistically colonized with little incidence but care should be taken in these results as genetic variability in insects and plants, as well as plant physiological state, might have an impact on the pest survivability. [less ▲]

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See detailApproche contingente du design du système d’information comptable dans les PMI tunisiennes
Ghorbel, Jihene ULg

Conference (2015, May 19)

Malgré les recherches qui sont de plus en plus nombreuses sur le système d’information comptable dans les PME, les résultats trouvés sont mitigés et contradictoires. Ainsi, nous essayons à travers ce ... [more ▼]

Malgré les recherches qui sont de plus en plus nombreuses sur le système d’information comptable dans les PME, les résultats trouvés sont mitigés et contradictoires. Ainsi, nous essayons à travers ce travail de contribuer au débat relatif du design du système d’information comptable dans les PMI des pays en voie de développement comme la Tunisie. Dans une optique comptable et face aux défis auxquels se trouvent confrontées les entreprises et pour légitimer leur compétitivité et leur crédibilité, nous nous intéressons à une série de facteurs structurels et comportementaux susceptibles de mieux cerner le design du système d’information comptable. En recourant aux méthodes des équations structurelles, cette recherche révèle que le design du système d’information comptable auprès de 221 PMI est influencé par plusieurs facteurs contextuels. [less ▲]

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See detailThe influence of lithology on the mechanical strength and porosity of terra-cotta, the case study of Marrakech region (Morocco).
El Boudour El Idrissi, Hicham ULg; Daoudi, Lahcen; Collin, Frédéric ULg et al

Poster (2015, May 19)

The ceramic pastes in Marrakech region are prepared on the base of six types of raw materials of different lithologies. Various products are manufactured. The production consists of cooking utensils ... [more ▼]

The ceramic pastes in Marrakech region are prepared on the base of six types of raw materials of different lithologies. Various products are manufactured. The production consists of cooking utensils (based on schist, colluviums, quartzose sand and silt), decoration products (based on argillite, washing residues and soil), vases and gourds products (based on schist and soil), tiles (based on silt decantation) and traditional dishes (based on soil and argillite). In this study we elaborate bricks from the different raw material and we evaluate some of their physical properties after firing at 1050°C. In particular we measure the porosity to water and the mechanical strength of all the fired bricks. The aim is to compare the final product quality according to the origin (lithology) of the clayey raw material of the ceramic pastes. Based on our experiments, the bricks of the lower compressive strength (CS) and of the lower flexural strength (FS) are those based on sand (CS = 39 MPa; FS = 7 MPa), on silt decantation (CS = 25 to 39 MPa; FS = 10 to 18 MPa), and on schist and colluviums (CS = 20 to 51 MPa; FS = 6 to 17 MPa). Those of the highest values are based on argillites (CS = 33 to 102 MPa; FS = 13 to 28 MPa). The other pastes are characterized by intermediate values. The porosity ranges between 5 to 27%. The bricks based on silt decantation have the greatest values (20 to 27%), whereas those based on argillite have the lower values (5 to 10%). Those physical properties are, in most cases, in agreement with the requested values of the bricks industry. We conclude that such raw materials have high perspective to manufacture structural products of high performance in mechanical strength and thermal insulation. [less ▲]

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