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See detailTemporal habitat shift of a polymorphic newt species under predation risk
Winandy, Laurane ULg; Colin, Mélanie; Denoël, Mathieu ULg

in Behavioral Ecology (2016), 27(4), 1025-1032

The temporal partitioning hypothesis suggests that the evolution of different diel activity rhythms in animals might facilitate the coexistence between prey and predators. However, the temporal shift of ... [more ▼]

The temporal partitioning hypothesis suggests that the evolution of different diel activity rhythms in animals might facilitate the coexistence between prey and predators. However, the temporal shift of habitat use induced by predation has rarely been observed. The study of such a mechanism is particularly relevant for introduced species because it might explain how native species can persist or decline in response to the presence of alien species. The introduction of fish into ponds inhabited by amphibians has severe consequences for their occurrence and abundance. Fish particularly affect an alternative newt phenotype, the paedomorph, which does not undergo metamorphosis and maintains larval traits such as gills at the adult stage. In a laboratory design, we assessed the diel patterns of habitat use in the 2 distinct morphological phenotypes of palmate newt (Lissotriton helveticus) in the presence or absence of goldfish (Carassius auratus). Both newt phenotypes avoided a risky habitat more in the presence than in the absence of fish. This habitat shift was more pronounced during the daytime (i.e., when the risk could be considered higher for the newts) than during nighttime. However, in contrast to metamorphs, paedomorphs showed less adaptive changes according to temporal risk and remained in their shelter for most of the time. Temporal and habitat partitioning at the diel scale between native and alien species might promote their coexistence, but diel change can also imply a cost in the overall reduction of the time allocated to essential activities, showing that species interactions remain complex. [less ▲]

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See detailQuand Caïn scrute Abel. Reflets mutuels des neutralités belge et suisse autour de la Première Guerre mondiale
Genin, Vincent ULg

in Revue Générale (2016), 2016/4(juillet-août),

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See detailCognitive processes across anxiety disorders related to intolerance of uncertainty: Clinical Review
Vander Haegen, Marie ULg; Etienne, Anne-Marie ULg

in Cogent Psychology (2016), 3

Abstract: Objective: Being a relatively recent concept, the intolerance of uncertainty (IU) suffers from inconsistent definitions and conceptual overlap. The core objective of the study is to clarify its ... [more ▼]

Abstract: Objective: Being a relatively recent concept, the intolerance of uncertainty (IU) suffers from inconsistent definitions and conceptual overlap. The core objective of the study is to clarify its clinical manifestations and its involved cognitive processes. Method: The procedure is based on algorithms (equations of keywords) encoded simultaneously in databases (Scopus, PubMed, and PsycArticles). Results are filtered by the year (range of 10 years [2005–2015] because it is a recent concept) and the relevance of abstracts. Once the studies are appraised, results are categorized in two groups: studies which examine the IU in a clinical perspective (relations with one or several anxiety disorders) (cluster A) and those which measure the IU through a cognitive perspective (cognition, metacognition) (cluster B). Results: 66 results are retrieved: 50 results concern the cluster A and 16 examine the cluster B. The state of the IU varies between studies (e.g. predictor and mediator), which make comparisons difficult. Notwithstanding, the IU construct seems to be a broad transdiagnostic maintaining risk factor involved in a range of psychological disorders. Conclusion: This clustering supported that researchers and clinicians may benefit from incorporating IU within cognitive and computational research design and as a specific treatment target. [less ▲]

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See detailLa radicalité feutrée de la droite espagnole
Molina Marmol, Maïté ULg; Muñoz, Ángeles

in Aide Mémoire (2016), 77

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See detailBoosting shape classifiers accuracy by considering the inverse shape
Pierard, Sébastien ULg; Lejeune, Antoine ULg; Van Droogenbroeck, Marc ULg

in Journal of Pattern Recognition Research (2016), 11(1), 41-54

Many techniques exist for describing shapes. These techniques almost exclusively consider the contour or the inside of the shape; the major problem for describing the outside of a shape, or inverse shape ... [more ▼]

Many techniques exist for describing shapes. These techniques almost exclusively consider the contour or the inside of the shape; the major problem for describing the outside of a shape, or inverse shape, being that it has an infinite extension. In this paper, we show how to adapt two shape descriptors, one region based, the Cover By Rectangles, and one transform based, the Zernike moments, to be applicable to the inverse shape. We analyze their properties, and show how to deal with the infinite extension of the inverse shape. Then, we apply these descriptors to shape classification and compare representations that use the shape, its inverse, or both. Our experiments establish that, for shape classification, a representation integrating the inverse shape often outperforms a representation restricted to the shape. This opens the path for better techniques that could use, as a rule of thumb, both the representations of a shape and its inverse for the purpose of classification. [less ▲]

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See detailCrossroads - le magazine sonore du blues et des musiques africaines américaines
Sacré, Robert ULg

Diverse speeche and writing (2016)

Programme radio hebdomadaire consacré aux musiques africaines américaines ; en streaming: www.equinoxefm.be ; les podcasts www.mixcloud.com/robertsacre9

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See detailObservational signatures of past mass-exchange episodes in massive binaries : The cases of LSS 3074 and HD 17505
Raucq, Françoise ULg; Rauw, Grégor ULg; Gosset, Eric ULg et al

Poster (2016, July)

Mass and angular momentum exchanges through Roche Lobe Overflow interactions within close massive binaries are known to play an important role in the subsequent evolution of the components of such systems ... [more ▼]

Mass and angular momentum exchanges through Roche Lobe Overflow interactions within close massive binaries are known to play an important role in the subsequent evolution of the components of such systems, and produce several observational signatures, such as asynchronous rotation and altered chemical compositions, that remain once the stars detach again. We have started to investigate these effects in a sample of massive O-star binaries that are thought to have previously experienced a Case A Roche Lobe Overflow episode. Using phase-resolved spectroscopy, we perform the disentangling of the optical spectra of the two stars. The reconstructed primary and secondary spectra re then analysed with the CMFGEN model atmosphere code to determine stellar parameters such as the effective temperatures, surface gravities and rotational velocities, and to constrain the chemical composition of the components. In this contribution, we present the results of our analyses of LSS 3074 (O5.5I + O6.5-7I, P = 2.1852 days), together with the analyses of its photometric lightcurve and orbital solution. We also present the first results of our analyses of the triple system HD17505 ([O7.5V + O7.5V, P = 8.57 days] + O6.5III). [less ▲]

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See detailLeveraging orientation knowledge to enhance human pose estimation methods
Azrour, Samir ULg; Pierard, Sébastien ULg; Van Droogenbroeck, Marc ULg

in Articulated Motion and Deformable Objects AMDO 2016 (2016, July)

Predicting accurately and in real-time 3D body joint positions from a depth image is the cornerstone for many safety, biomedical, and entertainment applications. Despite the high quality of the depth ... [more ▼]

Predicting accurately and in real-time 3D body joint positions from a depth image is the cornerstone for many safety, biomedical, and entertainment applications. Despite the high quality of the depth images, the accuracy of existing human pose estimation methods from single depth images remains insufficient for some applications. In order to enhance the accuracy, we suggest to leverage a rough orientation estimation to dynamically select a 3D joint position prediction model specialized for this orientation. This orientation estimation can be obtained in real-time either from the image itself, or from any other clue like tracking. We demonstrate the merits of this general principle on a pose estimation method similar to the one used with Kinect cameras. Our results show that the accuracy is improved by up to 45.1 %, with respect to a method using the same model for all orientations. [less ▲]

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See detailSusceptibility of pigs to zoonotic hepatitis E virus genotype 3 isolated from a wild boar
Thiry, Damien ULg; Rose, Nicolas; Mauroy, Axel ULg et al

in Transboundary and Emerging Diseases (2016)

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See detailSPARC Report on the Mystery of Carbon Tetrachloride
Ahmadzai, H; Bock, R P; Burkholder, J B et al

in Liang, Qing; Newman, Paul A; Reimann, Stefan (Eds.) SPARC Report on the Mystery of Carbon Tetrachloride (2016)

The Montreal Protocol (MP) controls the production and consumption of carbon tetrachloride (CCl4 or CTC) and other ozone-depleting substances (ODSs) for emissive uses. CCl4 is a major ODS, accounting for ... [more ▼]

The Montreal Protocol (MP) controls the production and consumption of carbon tetrachloride (CCl4 or CTC) and other ozone-depleting substances (ODSs) for emissive uses. CCl4 is a major ODS, accounting for about 12% of the globally averaged inorganic chlorine and bromine in the stratosphere, compared to 14% for CFC-12 in 2012. In spite of the MP controls, there are large ongoing emissions of CCl4 into the atmosphere. Estimates of emissions from various techniques ought to yield similar numbers. However, the recent WMO/UNEP Scientific Assessment of Ozone Depletion [WMO, 2014] estimated a 2007-2012 CCl4 bottom-up emission of 1-4 Gg/year (1-4 kilotonnes/year), based on country-by-country reports to UNEP, and a global top-down emissions estimate of 57 Gg/ year, based on atmospheric measurements. This 54 Gg/year difference has not been explained. In order to assess the current knowledge on global CCl4 sources and sinks, stakeholders from industrial, governmental, and the scientific communities came together at the “Solving the Mystery of Carbon Tetrachloride” workshop, which was held from 4-6 October 2015 at Empa in Dübendorf, Switzerland. During this workshop, several new findings were brought forward by the participants on CCl4 emissions and related science. • Anthropogenic production and consumption for feedstock and process agent uses (e.g., as approved solvents) are reported to UNEP under the MP. Based on these numbers, global bottom-up emissions of 3 (0-8) Gg/year are estimated for 2007-2013 in this report. This number is also reasonably consistent with this report’s new industry-based bottom-up estimate for fugitive emissions of 2 Gg/year. • By-product emissions from chloromethanes and perchloroethylene plants are newly proposed in this report as significant CCl4 sources, with global emissions estimated from these plants to be 13 Gg/year in 2014. • This report updates the anthropogenic CCl4 emissions estimation as a maximum of ~25 Gg/year. This number is derived by combining the above fugitive and by-product emissions (2 Gg/year and 13 Gg/year, respectively) with 10 Gg/year from legacy emissions plus potential unreported inadvertent emissions from other sources. • Ongoing atmospheric CCl4 measurements within global networks have been exploited for assessing regional emissions. In addition to existing emissions estimates from China and Australia, the workshop prompted research on emissions in the U.S. and Europe. The sum of these four regional emissions is estimated as 21±7.5a Gg/year, but this is not a complete global accounting. These regional top-down emissions estimates also show that most of the CCl4 emissions originate from chemical industrial regions, and are not linked to major population centres. • The total CCl4 lifetime is critical for calculating top-down global emissions. CCl4 is destroyed in the stratosphere, oceans, and soils, complicating the total lifetime estimate. The atmospheric lifetime with respect to stratospheric loss was recently revised to 44 (36-58) years, and remains unchanged in this report. New findings from additional measurement campaigns and reanalysis of physical parameters lead to changes in the ocean lifetime from 94 years to 210 (157-313) years, and in the soil lifetime from 195 years to 375 (288-536) years. • These revised lifetimes lead to an increase of the total lifetime from 26 years in WMO [2014] to 33 (28-41) years. Consequently, CCl4 is lost at a slower rate from the atmosphere. With this new total lifetime, the global top-down emissions calculation decreases from 57 (40-74) Gg/year in WMO [2014] to 40 (25-55) Gg/year. This estimate is relatively consistent with the independent gradient top-down emissions of 30 (25-35) Gg/year, based upon differences between atmospheric measurements of CCl4 in the Northern and Southern Hemispheres. In addition, this new total lifetime implies an upper limit of 3-4 Gg/year of natural emissions, based upon newly reported observations of old air in firn snow. These new CCl4 emissions estimates from the workshop make considerable progress toward closing the emissions discrepancy. The new industrial bottom-up emissions estimate (15 Gg/year total) includes emissions from chloromethanes plants (13 Gg/year) and feedstock fugitive emissions (2 Gg/year). When combined with legacy emissions and unreported inadvertent emissions, this could be up to 25 Gg/year. Top-down emissions estimates are: global 40 (25-55) Gg/year, gradient 30 (25-35) Gg/year, and regional 21 (14-28) Gg/year. While the new bottom-up value is still less than the aggregated top-down values, these estimates reconcile the CCl4 budget discrepancy when considered at the edges of their uncertainties. [less ▲]

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See detailFleurs d’orange et encens pour la gloire du roi dans les fêtes françaises de 1622
De Marco, Rosa ULg

Scientific conference (2016, July)

Orange Flowers and Incense to the Glory of the King in the French Festivals of 1622 The communication explores the way in which the festival apparatus establishes a sacred dimension in the ordinary space ... [more ▼]

Orange Flowers and Incense to the Glory of the King in the French Festivals of 1622 The communication explores the way in which the festival apparatus establishes a sacred dimension in the ordinary space and time of the city. We consider the immaterial devices of the spectacular apparatus: light, sound, with special attention to the smell, its iconic power and liturgical significance. The study is conducted on the iconographic and textual descriptions of two kind of celebrations which took place during the summer and autumn of 1622 in France: Louis’s triumphal entries following his victories against the Protestant rebels, and the solemnities for canonization of Jesuits Ignatius of Loyola and Francis Xavier, miles of catholic faith between Europe and Asia. In this historical perspective where sacred/secular points converge, these festivals contribute to shape the imago gloriae on the urban space through the ephemeral language of festival and its indelible poli-sensory effect on audience’s memory. [less ▲]

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See detailPlant mitochondrial complex I composition and assembly: a review
Subrahmanian, Nitya; Remacle, Claire ULg; Hamel, Patrice

in Biochimica et Biophysica Acta-Bioenergetics (2016), 1857(7), 1001-1014

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See detailPassive flutter suppression using a nonlinear tuned vibration absorber
Verstraelen, Edouard ULg; Gourc, Etienne ULg; Kerschen, Gaëtan ULg et al

Poster (2016, July)

A recent study showed that the addition of a linear tuned vibration absorber could increase the flutter speed of a rigid wing with pitch and flap degrees of freedom by about 35%. However, the absorber was ... [more ▼]

A recent study showed that the addition of a linear tuned vibration absorber could increase the flutter speed of a rigid wing with pitch and flap degrees of freedom by about 35%. However, the absorber was turning the initial super-critical bifurcation into a sub-critical one. This work shows numerically that adding a nonlinear restoring force to the absorber can restore the su- percritical behaviour of the bifurcation and further reduce the post-instability limit cycle amplitude. [less ▲]

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See detailPhilosophie et esthétique de la modernité: Approches phénoménologiques et sociologiques
Hagelstein, Maud ULg; Zincq, Aurélien ULg

in Bulletin d'Analyse Phénoménologique (2016), 12 (2016)(4),

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See detailMontage et résistance du réel chez S. Kracauer : Photographie, cinéma, texte
Hagelstein, Maud ULg; Hamers, Jérémy ULg

in Bulletin d'Analyse Phénoménologique (2016), 12 (2016)(4),

En tant que témoin et acteur des vifs débats sur le montage qui marquent l’Europe artistique et intellectuelle de l’après-guerre, Kracauer rédige dans les années 1920 une série de « feuilletons » sur la ... [more ▼]

En tant que témoin et acteur des vifs débats sur le montage qui marquent l’Europe artistique et intellectuelle de l’après-guerre, Kracauer rédige dans les années 1920 une série de « feuilletons » sur la modernité weimarienne repris dans L’Ornement de la masse (1963). Un texte en particulier retiendra ici notre attention qui permet de poser, en dehors des analyses vouées au cinéma, la question du montage. Ce texte, « Le Hall d’hôtel », est extrait d’un ouvrage sur le roman policier non publié à l’époque. Il vise à énoncer le problème du sens dans une société où la religion s’effondre progressivement. Selon Kracauer, la production artistique est toute entière prise dans cette vocation de solutionner la perte de sens consécutive à la modernité. Comme il l’évoque en des termes apparemment naïfs, plus le monde se déréalise, plus l’art doit exercer son rôle d’éducateur2. Là où le monde est devenu muet, là où son sens général s’est obscurci, la forme esthétique peut encore produire selon Kracauer une « sorte de langage ». L’art permet en effet d’exprimer à nouveaux frais les relations existant entre des éléments décousus et « reposant les uns à côté des autres en ordre dispersé ». Vecteur d’une sortie de l’état désenchanté du monde moderne, l’éducateur se définit par conséquent chez Kracauer comme celui qui relie entre eux des éléments épars. Et l’artiste devient bien un tel éducateur lorsqu’il vise, à travers un « organisme esthétique », une totalité qui permet de ressaisir les « éléments d’un monde en décomposition dispersés à l’aveuglette »3. Or, dans ce texte de jeunesse déjà, Kracauer introduit une nuance : car si le rôle de l’artiste est déterminant dans sa tentative de résoudre le désenchantement du monde, il risque aussi de s’engager sur la voie néfaste qui consisterait à ré-enchanter le monde de manière abusive. Face à ces éléments dispersés qu’il s’agit de réorganiser, l’artiste peut soit être un véritable éducateur-voyant et restituer avec justesse les liens entre les éléments (il est alors du côté du « bon » montage qui respecte la réalité), soit construire un monde totalement artificiel, potentiellement enclin à donner une idée fausse de la réalité, voire idéologiquement trompeuse, en somme une sorte de « mauvais » montage. Kracauer se méfiera jusqu’à la fin de sa vie de ce montage-là, sans cependant jamais définir précisément le « principe de réalité » auquel s’adosse la normativité établie par lui comme fondement de toute l’esthétique matérielle. [less ▲]

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See detailEuropean Commission, trade agreements, and diversity of cultural expressions: between autonomy and influence
Vlassis, Antonios ULg

in European Journal of Communication (2016), 31(4)

The Convention on diversity of cultural expressions – adopted by United Nations Educational, Scientific and Cultural Organization in 2005 – is a main international instrument within the global governance ... [more ▼]

The Convention on diversity of cultural expressions – adopted by United Nations Educational, Scientific and Cultural Organization in 2005 – is a main international instrument within the global governance of cultural and audiovisual industries. For its part, the European Commission played a critical role in the negotiation, leading to the Convention on Diversity of Cultural Expressions’ adoption. In this respect, the article aims to explore why and how the Commission uses the Convention on Diversity of Cultural Expressions throughout the recent European Union trade negotiations, for which purposes and how the Convention on Diversity of Cultural Expressions influences the European Union foreign policy and its objectives. The article is more concerned with analysing the policy process through which the Commission’s strategy is formulated in light of the Convention on Diversity of Cultural Expressions and of the place of cultural and audiovisual industries within the European Union trade agreements and also concerned with understanding whether the Commission’s autonomy is transformed into influence within the policy process. [less ▲]

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See detailPerformances comparison of a laser ultrasonic system using 10.6 µm infrared or 532 nm visible generation beam for the investigation of CFRP
Vandenrijt, Jean-François ULg; Walter, Julien; Brouillette, Tomy et al

Conference (2016, July)

The investigation of complex shaped carbon fiber parts is a common need of the industry. Classical ultrasonic systems are commonly used, wide-spread and very efficient. However, these techniques are often ... [more ▼]

The investigation of complex shaped carbon fiber parts is a common need of the industry. Classical ultrasonic systems are commonly used, wide-spread and very efficient. However, these techniques are often limited to simple shape objects. Major problems arise when the shape of the element to be investigated is complex (peak, valley, small radius of curvature…). To overcome these problems laser ultrasonic systems can be used and the recent developments show promising results. Laser ultrasonic systems can use different wavelengths for ultrasound generation. Usually CO2 lasers emitting at 10.6 µm wavelength are used. When a laser ultrasonic system is mounted on a robotic arm, very complex shaped objects can be considered. However, the optical fibers for 10.6 µm wavelength are not capable to cope with laser ultrasonic system requirements. Therefore, infrared systems use jointed articulated beam delivery systems which reduce the flexibility of the robot arm and significantly limit the feasible scan paths. To circumvent this limitation, an all-fibered laser ultrasonic system can be used. In our case the ultrasound is generated with a pulsed laser operating at 532 nm. This system is placed on a robotic arm, the beam delivery is performed through an optical fiber only. Therefore, this system is capable of analyzing very complex shaped objects due to the use of optical fiber only for laser beam transport. But visible generation is known to be less efficient and produces lower quality signals. In order to balance the advantages and limitations of both of these systems a CFRP plate including artificial defects has been investigated with different ultrasonic systems. First we used classical phased-array ultrasounds as a reference to compare the performances of visible and infrared generation systems. The plate has then been investigated with a 10.6 µm laser ultrasonic system. The results are compared with an all-fibered laser ultrasonic system working at 532 mn wavelength. Data acquired by each system allow comparing the visibility of the ultrasonic echoes and the amplitude of background noise. We observe the impact of frequency filtering. We show the main differences on the A-scans and C-scan generated by each system. From these elements, we show the advantages and limitations of each system for the investigation of CFRP with a focus on complex shaped object. [less ▲]

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See detailStudy of Mezoneuron benthamianum, a plant traditionally used against malaria in Guinea
Tchinda Tiabou, Alembert ULg; Loua, Jean; Esters, Virginie ULg et al

Poster (2016, July)

Despite some improvements in malaria control, this parasitic disease remains a major public health problem in many African countries, causing about 400 000 deaths/year through the continent, mainly by ... [more ▼]

Despite some improvements in malaria control, this parasitic disease remains a major public health problem in many African countries, causing about 400 000 deaths/year through the continent, mainly by children under the age of five (WHO, 2015). In Guinea, the leaves of Mezoneuron benthamianum Baill. are traditionally used to treat malaria (Traore et al., 2013) and showed a good antiplasmodial activity in an antiprotozoal in vitro screening (Traore et al., 2014), as well as promising results in a preliminary small-scale ethnomedical study (unpublished data), encouraging us to continue the study of this plant. The aim of this work was to evaluate the activity of M. benthamianum leaves extracts against P. falciparum using an in vitro test model (p-LDH assay) and to undertake a bio-guided fractionation to identify the compounds responsible for the activity. Hydroethanolic extracts (70% v/v) of M. benthamianum leaves showed a moderate in vitro activity against P. falciparum 3D7, with IC50 = 22.5 – 32.6 µg/ml, depending on the batch; while a dark precipitate formed during ethanol evaporation showed higher activity (IC50 = 6,5µg/ml). The bioguided fractionation was performed on this most active fraction and allowed the isolation of three diterpens, two flavonoids, resveratrol, gallic acid and its ethylester, β-sitosterol glucoside and pheophorbide derivatives. The active compounds belong to several phytochemical classes, including flavonoids, pheophorbide and gallic acid derivatives, contributing together to the global antiplasmodial activity of the hydroalcoholic extract against P. falciparum parasite. This study gives some concrete evidence to support the ethnopharmacological use of Mezoneuron benthamianum leaves extract in the management of malaria. The active compounds can be further studied for their antiplasmodial potential, as well as their suitability to be used as quality markers for the standardization of this herbal drug from the Guinean traditional pharmacopeia. [less ▲]

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See detailSimulation of a two-slope pyramid made by SPIF using an adaptive remeshing method with solid-shell finite element
Velosa De Sena, José ULg; Guzmán Inostroza, Carlos Felipe ULg; Duchene, Laurent ULg et al

in International Journal of Material Forming (2016), 9(3), 259-434

Single point incremental forming (SPIF) is an emerging application in sheet metal prototyping and small batch production, which enables dieless production of sheet metal parts. This research area has ... [more ▼]

Single point incremental forming (SPIF) is an emerging application in sheet metal prototyping and small batch production, which enables dieless production of sheet metal parts. This research area has grown in the last years, both experimentally and numerically. However, numerical investigations into SPIF process need further improvement to predict the formed shape correctly and faster than current approaches. The current work aims the use of an adaptive remeshing technique, originally developed for shell and later extended to 3D “brick” elements, leading to a Reduced Enhanced Solid-Shell formulation. The CPU time reduction is a demanded request to perform the numerical simulations. A two-slope pyramid shape is used to carry out the numerical simulation and modelling. Its geometric difficulty on the numerical shape prediction and the through thickness stress behaviour are the main analysis targets in the present work. This work confirmed a significant CPU time reduction and an acceptable shape prediction accuracy using an adaptive remeshing method combined with the selected solid-shell element. The stress distribution in thickness direction revealed the occurrence of bending/unbending plus stretching and plastic deformation in regions far from the local deformation in the tool vicinity. [less ▲]

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See detailNew antimalarial compounds isolated from Poupartia borbonica, a Mascarene Islands endemic plant
Ledoux, Allison ULg; Jansen, Olivia ULg; St-Gelais, Alexis et al

Poster (2016, July)

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