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See detailSpecies diversity and abundance of aphids and their natural enemies in a crop association
Chevalier Mendes Lopes, Thomas ULg; Hatt, Séverin ULg; Starý, Petr et al

Poster (2015, November)

Crop associations can be efficient to reduce aphid populations, by disrupting the visual and olfactory location of host plants. However, increasing the chemical and structural complexity of vegetation can ... [more ▼]

Crop associations can be efficient to reduce aphid populations, by disrupting the visual and olfactory location of host plants. However, increasing the chemical and structural complexity of vegetation can also decrease the searching efficiency of predators and parasitoids, which are not always more abundant in complex habitats. Using attractive semiochemicals such as methyl salicylate (MeSA) combined with a crop association seems promising to maximise aphid control. We compared the abundances of aphids and their natural enemies between a wheat-pea mixture (with and without MeSA) and pure stands, using yellow traps and observations on plants. Significantly higher numbers of pea aphids (Acyrthosiphon pisum) were observed in the pure stand of pea compared with the mixture (with and without MeSA) in 2013 and 2014. Concerning aphid natural enemies, hoverfly larvae abundance was not significantly different between treatments in both years. Parasitoid mummies were significantly more abundant in the pure stand of pea compared with the mixture (with and without MeSA) in 2014. Fifty-two aphid species were collected in yellow traps, as well as 12 Aphidiinae and four Aphelinus species. Acyrthosiphon primulae, Aphelinus daucicola, Aphelinus fusciscapus, Aphidius asteris, Aphidius eadyi, Metopolophium frisicum, Praon barbatum, and Trioxys auctus were recorded for the first time in Belgium. Besides determining the effects of a wheat-pea mixture (with or without MeSA) on aphid control, this study contributed to increase the knowledge on aphid and their parasitoid diversity in Belgium, by recording new species and establishing the first Aphidiinae and Aphelinus national checklist. [less ▲]

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See detailActivity vs. Stability: a multi-proxy approach to reconstruct fluvial morphodynamics of Wadi Selloum in the vicinity of the rock shelter Ifri n’ammar (Morocco)
Bartz, Melanie; Rhixon, Gilles; El Ouahabi, Meriam ULg et al

Conference (2015, November)

The impact of environmental changes on the emergence and dispersal of anatomically modern humans (AMH) is particularly important in North Africa, since the Straits of Gibraltar might have served as ... [more ▼]

The impact of environmental changes on the emergence and dispersal of anatomically modern humans (AMH) is particularly important in North Africa, since the Straits of Gibraltar might have served as western migration route for AMH from Africa to Europe. The prehistoric rock shelter of Ifri n’Ammar in NE Morocco reveals discontinuous Middle and Late Palaeolithic occupation phases since ~170 ka. Our study focuses on Wadi Selloum deposits to unravel palaeoenvironmental features and geomorphological aspects of the direct vicinity of Ifri n’Ammar. As a tributary of the Moulouya River, the catchment area of this ephemeral stream amounts to ~290 km², spanning elevations between ~700 and 200 m above sea level. Headwaters of the 35 km long Wadi Selloum drain Mesozoic limestone and dolomite. The application of luminescence dating techniques on Wadi Selloum deposits yielded burial ages between 1.3 ± 0.2 ka and 78 ± 7 ka, covering morphodynamically stable and active phases. Overbank fines include well-developed soil horizons as evidence of stability and of more humid periods than today around 80 ka and during the Holocene. This is supported by pedofeatures discovered in thin sections as well as the composition of clay minerals of the wadi sediments. Disordered clay minerals and partly illite/chlorite mixed-layer characterize the soil levels. Levels relatively rich in chlorite, illite, ankerite and quartz are interpreted as corresponding to relatively dry periods, while more humid periods lead to more intensive weathering and consequently to the dominance of clay minerals more advanced in the relative stability scale, such as kaolinite. Smectite is taken to indicate a climate with contrasting seasons and a pronounced dry season. In contrast, coarse-grained deposits, which are partly characterised by calcrete layers, point to drier conditions after 80 ka and 14 ka. In addition, the lack of palaeosols confirms morphodynamic activity during these periods. Acknowledgement. This research is supported by the German Research Foundation (DFG) within the framework of the CRC 806 “Our Way to Europe” (http://www.sfb806.uni-koeln.de/). [less ▲]

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See detailThe genome of a tortoise herpesvirus (testudinid herpesvirus 3) has a novel structure and contains a large region that is not required for replication in vitro or virulence in vivo.
Gandar, Frederic ULg; Wilkie, Gavin S.; Gatherer, Derek et al

in Journal of Virology (2015), 89(22), 11438-11456

Testudinid herpesvirus 3 (TeHV-3) is the causative agent of a lethal disease affecting several tortoise species. The threat that this virus poses to endangered animals is focusing efforts on ... [more ▼]

Testudinid herpesvirus 3 (TeHV-3) is the causative agent of a lethal disease affecting several tortoise species. The threat that this virus poses to endangered animals is focusing efforts on characterizing its properties, in order to enable the development of prophylactic methods. We have sequenced the genomes of the two most studied TeHV-3 strains (1976 and 4295). TeHV-3 strain 1976 has a novel genome structure and is most closely related to a turtle herpesvirus, thus supporting its classification into genus Scutavirus, subfamily Alphaherpesvirinae, family Herpesviridae. The sequence of strain 1976 also revealed viral counterparts of cellular interleukin-10 and semaphorin, which have not been described previously in members of subfamily Alphaherpesvirinae. TeHV-3 strain 4295 is a mixture of three forms (m1, m2, and M), in which, in comparison to strain 1976, the genomes exhibit large, partially overlapping deletions of 12.5 to 22.4 kb. Viral subclones representing these forms were isolated by limiting dilution assays, and each replicated in cell culture comparably to strain 1976. With the goal of testing the potential of the three forms as attenuated vaccine candidates, strain 4295 was inoculated intranasally into Hermann's tortoises (Testudo hermanni). All inoculated subjects died, and PCR analyses demonstrated the ability of the m2 and M forms to spread and invade the brain. In contrast, the m1 form was detected in none of the organs tested, suggesting its potential as the basis of an attenuated vaccine candidate. Our findings represent a major step toward characterizing TeHV-3 and developing prophylactic methods against it. [less ▲]

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See detailRimbaud fétiche
Saint-Amand, Denis ULg

Conference (2015, November)

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See detailHistoires sur Able Archer
Kluge, Alexander; Leyh, Valérie ULg

in Cahiers d'Etudes Germaniques (2015), 69

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See detailFinite element modelling of composite structures under crushing load
Chiu, Louis N.S.; Falzon, Brian G.; Boman, Romain ULg et al

in Composite Structures (2015), 131

This paper details the theory and implementation of a composite damage model, addressing damage within a ply (intralaminar) and delamination (interlaminar), developed for the simulation of the crushing of ... [more ▼]

This paper details the theory and implementation of a composite damage model, addressing damage within a ply (intralaminar) and delamination (interlaminar), developed for the simulation of the crushing of laminated composite structures. It includes a more accurate determination of the characteristic length to achieve mesh objectivity in capturing intralaminar damage consisting of matrix cracking and fibre failure, a load-history dependent material response, an isotropic hardening nonlinear matrix response, as well as a more physically-based interactive matrix damage mechanism. The developed damage model requires a set of material parameters obtained from a combination of standard and non-standard material characterisation tests. The fidelity of the model mitigates the need to manipulate, or “calibrate”, the input data to achieve good agreement with experimental results. This intralaminar damage model was implemented as a VUMAT subroutine, and used in conjunction with an existing interlaminar damage model, in Abaqus/Explicit. This approach was validated through the simulation of the crushing of a cross-ply composite tube with a tulip-shaped trigger, loaded in uniaxial compression. Despite the complexity of the chosen geometry, excellent correlation was achieved with experimental results. [less ▲]

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See detailLe crime de masse en criminologie
Pierre, Alexia ULg

in Revue de Science Criminelle et de Droit Pénal Comparé (2015), 3(juillet/septembre), 627-637

Despite the increasing number of mass crimes and mass victimisations, these topics remain marginal in criminology when they are not linked to terrorism. While the characteristics of mass crimes seem to ... [more ▼]

Despite the increasing number of mass crimes and mass victimisations, these topics remain marginal in criminology when they are not linked to terrorism. While the characteristics of mass crimes seem to meet the characteristics of a criminological object of research, they remain mostly studied through history, sociology, psychology or policy studies. The following analysis is an exploration of three issues that can explain the weakness of interest in mass crimes by the criminologists. These aspects, encompassing psychological, epistemological or practical issues, may lead to a disciplinary approach that is far from mass crimes specificities, or may not allow to explore the complex wholeness of such topics. A criminology of mass crimes, conducive to an exploration of the current criminal realities, is needed to understand the current global phenomena. Indeed, the numerous and worldwide massive abuses against civilians must lead the criminologists to take them into concern and to develop principles of prevention. Analysis, aware of the specificities of mass crimes, and leading to an in depth understanding of mass crimes issues, must be the foundation of these principles. [less ▲]

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See detailLégitimité des recommandations sur la viscosupplémentation
Henrotin, Yves ULg

in Rhumatos (2015), 12(111), 280

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See detailParage et Chirurgie du Pied de Bovin
Sartelet, Arnaud ULg; Frisee, Vincent ULg

Conference given outside the academic context (2015)

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See detailLa collection "Poétique" : terre d'accueil
Lorent, Fanny ULg

in A l'épreuve (2015), 2

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See detailFire Design of Steel Structures Second edition : Eurocode 1: Actions on structures. Part 1-2: Actions on structures exposed to fire: Eurocode 3: Design of steel structures: Part 1-2: Structural fire design
Franssen, Jean-Marc ULg; Vila Real, Paulo

Book published by Wiley (2015)

The first edition of Fire Design of Steel Structures was published by ECCS as paperback in 2010. Since 2012, this publication is also available in electronic format as an e-book. Nevertheless, the ... [more ▼]

The first edition of Fire Design of Steel Structures was published by ECCS as paperback in 2010. Since 2012, this publication is also available in electronic format as an e-book. Nevertheless, the interest for this publication was so high that it appeared rapidly that the paper copies would be sold out within a short time and a second edition would have to be printed. The authors took the opportunity of this second edition to review their own manuscript. The standards that are described and commented in this book, namely EN 1991-1-2 and 1993-1-2, are still in application in the same versions as those that prevailed at the time of writing the first edition. It was nevertheless considered that an added value would be given by, first, rephrasing some sentences or sections that had generated questions by some readers but, above all, adding some new material for the benefit of completeness. The new material namely comprises:  A section dealing with the thermal response of steel members under several separate simultaneous localised fires, including one worked example with multiple fire scenarios in a car park (Chapter 4);  An important section on classification of cross-sections. The case of combined bending and axial force, including one worked example comparing different methodologies to obtain the position of the neutral axis, has been added (Chapter 5);  A worked example of a beam-column with Class 4 cross-section (Chapter 5);  A new section with comparisons between the simple and the advanced calculation models in Chapter 6 (shadow factor – including one example, buckling curves and adaptation factors κ1 and κ2);  New references have been included. [less ▲]

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See detailSéance de renforcement musculaire utilisant des objets du quotidien
Dubru, Gilles ULg; Cloes, Marc ULg

in Revue de l'Education Physique (2015), 55(1), 43-56

Les professeurs d’éducation physique proposent régulièrement des leçons portant sur le renforcement musculaire faisant partie des compétences à acquérir par les élèves (domaine de la condition physique ... [more ▼]

Les professeurs d’éducation physique proposent régulièrement des leçons portant sur le renforcement musculaire faisant partie des compétences à acquérir par les élèves (domaine de la condition physique). En revanche, il n'est pas nécessairement fréquent que ces séances visent à expliquer aux élèves comment ils peuvent exploiter ce qu'ils apprennent à l'école lorsqu'ils sont chez eux. Cet article illustre une approche susceptible de combler ce manque. [less ▲]

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