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See detailA shared repository of hieroglyphic signs: The Thot sign-list
Polis, Stéphane ULg; Rosmorduc, Serge

Conference (2015, August 27)

The principles to be taken into consideration for building a hieroglyphic sign list have been discussed for quite some time (Schenkel 1977), and recently received renewed and additional attention (Meeks ... [more ▼]

The principles to be taken into consideration for building a hieroglyphic sign list have been discussed for quite some time (Schenkel 1977), and recently received renewed and additional attention (Meeks 2013, Polis & Rosmorduc 2013). The catalogs of hieroglyphic signs (e.g. Buurman et al. 1988, Grimal et al. 1993), however, did not implement these principles, since their goal was rather to allow for the encoding and rendering (either on paper or on screen) of as many hieroglyphs as possible. As a result, hieroglyphic text editors (Gozzoli 2013) will usually do the trick when one aims at displaying hieroglyphic texts, but in its current state, the Manuel de Codage makes the creation of annotated corpora that include hieroglyphs problematic (Nederhof 2013). In this paper, we do not focus on issues pertaining to the relative positioning of hieroglyphs (Nederhof 2002), but on another — more essential — problem, namely the hieroglyphic sign-list itself. Existing sign-lists suffer from the fact that they are (1) unstructured, (2) unreferenced, and (3) non-described. Based on our experience with respect to the encoding of hieroglyphic spellings in the Ramses corpus (Polis et al. 2013; Polis & Winand 2013), we present a beta version of the Thot sign-list, which has the following features (see the discussion in Polis & Rosmorduc 2013): 1. The sign-list is structured: each hieroglyph of the sign-list belongs to one of the three following categories: grapheme, class and shape (from the more abstract to the more concrete, see also Meeks 2013). 2. Signs are referenced: each sign is accompanied by at least one reference to a publication in which the hieroglyph is used in context. For this purpose, the unpublished lists of hieroglyphic signs compiled by Hornung and Schenkel have been instrumental. We are much grateful to both of them for sharing this material with us and allowing us to use it in this context. 3. Signs are described at two levels: a. The functions that each hieroglyph can fulfill (Polis & Rosmorduc in press), with illustrative examples for each function. b. The salient iconic features of each hieroglyph, based on a controlled vocabulary. Practically, the Thot sign-list is a Wiki, i.e., a web application that allows collaborative modification of its content and structure. Thanks to the Semantic Mediawiki extension, one can create links between any signs sharing a given property. The goal is obviously to allow any Egyptologist to enrich the structured sign-list Thot with new signs, references and descriptions. [less ▲]

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See detailElicitor screening to protect wheat against Zymoseptoria tritici
Le Mire, Géraldine ULg; SIAH, ALI; Deleu, Magali ULg et al

Conference (2015, August 27)

Plants face an array of biotic and abiotic stresses in their environment, making it necessary to use various chemical inputs to maintain satisfactory yield. Today, conventional agriculture is evolving ... [more ▼]

Plants face an array of biotic and abiotic stresses in their environment, making it necessary to use various chemical inputs to maintain satisfactory yield. Today, conventional agriculture is evolving towards more sustainable practices, out of respect for human health and the environment. Elicitors are considered as promising biological control tools and draw major interest in IPM strategies. These plant-immunity triggering compounds, also called “stimulators of plant natural defenses”, induce a general and systemic resistance in the plant to various diseases. Although numerous elicitors have already been identified and some of them reached the market since the late 1970s, further investigations are still required to better understand the mode of action of these molecules in the plant and ensure a consistent efficiency under various field conditions. Few elicitors have yet been successfully tested and formulated to protect monocotyledonous crop plants such as wheat, which is cultivated over large areas in Europe. This study focuses on the screening of ten potential elicitor products of various origins and structures to protect winter wheat against the fungal pathogen Zymoseptoria tritici. Greenhouse trials were carried out to measure the ability of the different products to reduce disease foliar symptoms (necrosis, chlorosis and pycnidia). Topical spraying treatments with 3 different concentrations of each product were carried out 5 days before pathogen inoculation. Disease severity (% of symptoms on the total surface of the third leaf) was then scored every 2 days up to 28 days post-inoculation. In addition, phytotoxicity and biocide activity of these products was evaluated under greenhouse and laboratory conditions, respectively. The corresponding results will be presented and discussed with the perspective to choose the best elicitor candidates and to undertake investigations on the signaling pathway and the influence of environmental parameters on the elicitation capacity. [less ▲]

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See detailRamses goes Online. An annotated corpus of Late Egyptian texts in interaction with the Egyptological community
Polis, Stéphane ULg; Rosmorduc, Serge; Winand, Jean ULg

Conference (2015, August 27)

The Ramses project was first introduced to Egyptologists in 2008, during the 10th interna-tional congress of Egyptologists held in Rhodes (Winand et al. in press). After eight years of IT developments ... [more ▼]

The Ramses project was first introduced to Egyptologists in 2008, during the 10th interna-tional congress of Egyptologists held in Rhodes (Winand et al. in press). After eight years of IT developments (under the responsibility of S. Rosmorduc) and of annotation of Late Egyptian texts (Polis et al. 2013; Polis & Winand 2013), the data can now progressively be made available online. After an introduction providing general information about the annotated corpus (510 000+ tokens; 65 000+ hieroglyphic spellings; 10 000+ lemmata; 4000+ texts), this paper will focus on three main aspects: 1. Description of the functionalities of the annotating tool (the TextEditor), with a special attention to the metadata that are used for describing the documents and texts that are integrated in the corpus. This section will include proposals regarding the creation of shared thesauri for describing (written) Egyptian material. 2. Discussion of the solution that has been designed for handling the evolution of the database (see already Rosmorduc 2013), both as regards its content — namely, any change that affects texts, lemmata, inflexions, spellings, etc. — and its structure — types and structure of the metadata, evolution of the texts representation format, etc. In a nutshell, the new database will use the technique of event sourcing, where the database is seen as a sequence of editing events, which allows both “time travel” in the database history, and easy fix of editing mistakes. 3. Presentation of the first Online version of Ramses. Several corpora of Late Egyptian texts (the so-called Tomb Robberies, the Late Egyptian Stories, the Late Ramesside letters and a selection of ostraca from Deir el-Medineh) will be made available for the first time at the occasion the 11th International Congress in Florence. The website will of course allow users to browse the annotated texts and lexemes, and to make simple or complex queries. Besides, we will also encourage Egyptologists to interact directly with the data, e.g., by flagging inaccuracies or signaling alternative analysis. [less ▲]

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See detailChallenges for the restoration of dry calcareous grasslands in quarries: does nature need help?
Pitz, Carline ULg; Piqueray, Julien; Harzé, Mélanie ULg et al

Conference (2015, August 26)

In order to maximize the biodiversity potential of dry calcareous grasslands in former quarries two options are available to managers: (i) allow species to spontaneously recolonize the site, (ii ... [more ▼]

In order to maximize the biodiversity potential of dry calcareous grasslands in former quarries two options are available to managers: (i) allow species to spontaneously recolonize the site, (ii) implement technical support for ecosystem restoration. This study aimed at characterizing the spontaneous communities established in dry area of unexploited quarries and at comparing communities encountered to the succession panel of dry grasslands. To evaluate the ecological succession in quarries, three successional stages where defined: (i) less than three years; (ii) three to 20 years; and (iii) more than 20 years after exploitation. For each successional stage, six parcels were selected and 20 1m2 plots were randomly marked in each parcel. All selected parcels presented dry grasslands abiotic conditions: filtering and stony soils and south orientation. During the 2014 vegetation period, percentage cover of higher plant species was recorded in each plot. Explaining environmental variables including coordinates, altitude, slope (degrees), soil depth, exposure, maximum vegetation height, bare ground cover, moss cover, and shrub cover (%) were measured. Our main results showed that, over decades of time, the ecological succession in dry area of unexploited quarries does not approach a typical formation of dry calcareous grassland. Most recolonizations tended to form meadows communities, except for three sites belonging to a specific landscape context. Potential implications for future quarries restoration will be discussed. [less ▲]

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See detailAnthropogenic landscape change: synthesis of the concepts and quantification methods
Andre, Marie ULg; Vranken, Isabelle ULg; Mahy, Grégory ULg et al

Conference (2015, August 26)

Anthropogenic disturbances impact the whole biosphere, at least indirectly, and are of major concern in various disciplines and policies. To tackle it, most studies, specific to their thematic, create ... [more ▼]

Anthropogenic disturbances impact the whole biosphere, at least indirectly, and are of major concern in various disciplines and policies. To tackle it, most studies, specific to their thematic, create their own reference framework without connection with related purposes in other disciplines. This results in a plethora of terms and concepts that in turn impedes addressing that issue on a comprehensive way as well as complementarity between studies. Here, we clarify and synthesize the most frequently employed terms to characterise human impact on the environment (anthropisation, naturalness, hemeroby, novel ecosystem, analogous ecosystem, climax, etc.), their synonyms, the nuances and relationships between each of them, as well as the concepts used to designate the responses given by humans to environmental disturbances (restoration, management, conservation). We go on reviewing the methods used to assess anthropogenic changes, exploring different branches of ecology and geography. The strengths and weaknesses of the existing approaches are then used as a basis to develop a new analytical framework: we propose an action-oriented type of naturalness, and we develop a general methodology to quantify landscape anthropisation. Our methodology combines object-oriented and gradient analyses. Moreover, it is based on the assessment of ecosystem disturbance, landscape configuration and dynamics as well as on easily acquired data sets. Our integrated approach of the concern could be at the basis of land planning, environmental restoration and management practices as well as policies. [less ▲]

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See detailGeophysical Investigation of the Pb-Zn deposit of Lontzen-Popplsberg, Belgium
Evrard, Maxime ULg

Conference (2015, August 26)

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See detailOutils d’aide à la réussite dans le cadre du cours de Biologie en Premier bachelier en Faculté des Sciences à l’Université de Liège : présentation et analyse
Thiry, Marc ULg; Rigo, Pierre ULg; Poffé, Corentin ULg

Conference (2015, August 26)

A l’Université de Liège, les cours du premier quadrimestre sont communs à certaines sections du premier bachelier de la Faculté des Sciences. Le programme de ce quadrimestre commun reprend un cours de ... [more ▼]

A l’Université de Liège, les cours du premier quadrimestre sont communs à certaines sections du premier bachelier de la Faculté des Sciences. Le programme de ce quadrimestre commun reprend un cours de biologie. Depuis plusieurs années, le titulaire de ce cours de biologie met en place diverses actions visant à favoriser la transition secondaire-université : séminaires, remédiations, aides à l’étude, forum, livre de référence, etc. Ces différentes actions font l’objet d’un suivi didactique, permettant un monitoring précis et une régulation au fil du temps. Dans un premier temps, la communication présentera l’état des lieux des outils mis à la disposition des étudiants en vue de favoriser leur réussite pour le cours de biologie, mais aussi pour les autres cours, par transfert des compétences acquises. Dans un second temps, le dispositif de suivi didactique des séances d'aide à l'étude et ses principaux résultats seront présentés. [less ▲]

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See detailperrénité et mutations des familles : approche sociologique
Gavray, Claire ULg

Conference (2015, August 26)

remise en cause des clichés concernant l'évolution de La Famille ; discussions autour des enjeux contemporains et futurs qui concernent les familles

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See detailThe harmonic balance method for bifurcation analysis of large-scale nonlinear mechanical systems
Detroux, Thibaut ULg; Renson, Ludovic ULg; Masset, Luc ULg et al

Conference (2015, August 26)

The harmonic balance (HB) method is widely used in the literature for analyzing the periodic solutions of nonlinear mechanical systems. The objective of this paper is to extend the method for bifurcation ... [more ▼]

The harmonic balance (HB) method is widely used in the literature for analyzing the periodic solutions of nonlinear mechanical systems. The objective of this paper is to extend the method for bifurcation analysis, i.e., for the detection and tracking of bifurcations of nonlinear systems. To this end, an algorithm that combines the computation of the Floquet exponents with bordering techniques is developed. A new procedure for the tracking of Neimark-Sacker bifurcations that exploits the properties of eigenvalue derivatives is also proposed. As an application, the frequency response of a structure spacecraft is studied, together with two nonlinear phenomena, namely quasiperiodic oscillations and detached resonance curves. This example illustrates how bifurcation tracking using the HB method can be employed as a promising design tool for detecting and eliminating such undesired behaviors. [less ▲]

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See detailPromoting quarries biodiversity through partnerships: a Belgian case study
Seleck, Maxime ULg; Harzé, Mélanie ULg; Pitz, Carline ULg et al

Conference (2015, August 25)

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected ... [more ▼]

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected though they are playing a significant role as stepping-stones and regulating green infrastructure in landscapes. In highly urbanized and controlled landscapes, quarries are an exceptional opportunity to maintain rare and threatened transient habitats hosting fugitive species. Such ephemeral biodiversity is hard to manage through a site legal protection status. As exploitation progresses, more permanent, biodiverse habitats settle in abandoned areas but the biologic potential could also be maximized by optimized groundwork through the whole exploitation process. Exploitation plans taking into consideration biodiversity could allow maximizing quarry biodiversity hosting capacity during the exploitation phase and in further rehabilitation schemes. Since 2012 Gembloux Agro-Bio Tech (University of Liège) provides support to FEDIEX - the Belgian federation of extractive industries – in its implementation of a sectorial charter on “Quarries and Biodiversity” that aims at i) raising members’ awareness; ii) promoting the integration of practical recommendations for the protection and management of biodiversity in exploitation plans; iii) quarries’ personnel trainings. Our presentation will trace realizations undertaken under this collaboration, among which the “Mr/Ms Biodiversity” training organized in 2013, 2014 and 2015, the publication of folders popularising the management and enhancement of nature in active quarries and the collaboration in the redaction of a “LIFE in Quarries” project (LIFE Biodiversity) submitted for the 2014 LIFE call. [less ▲]

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See detailCouvents de femmes en réseaux sur la Dorsale catholique
Henneau, Marie-Elisabeth ULg

Conference (2015, August 25)

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See detailL’appropriation du jeu vidéo: le cas des créateurs amateurs
Hurel, Pierre-Yves ULg

Conference (2015, August 25)

"Notre communication, basée sur les résultats de ces entretiens en cours, se concentrera sur les questions liées au début de l’activité des amateurs car ces dernières révèlent les étapes successives du ... [more ▼]

"Notre communication, basée sur les résultats de ces entretiens en cours, se concentrera sur les questions liées au début de l’activité des amateurs car ces dernières révèlent les étapes successives du processus d’appropriation d’un média généralement perçu comme lointain, complexe, hors de portée. Notre intervention montrera que la découverte d’un logiciel d’aide est vécue comme un évènement majeur du parcours de l’amateur, notamment parce qu’elle s’inscrit dans un processus d’appropriation qui était déjà en cours." [less ▲]

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See detailDoes combining a wheat and pea mixture with methyl salicylate reduces aphid populations in both crops?
Chevalier Mendes Lopes, Thomas ULg; Fassotte, Bérénice ULg; Hatt, Séverin ULg et al

Conference (2015, August 25)

Aphids are important pests of wheat and pea. Among the alternative methods to control them with less reliance on insecticides, crop associations already proved to be efficient. However, if increasing the ... [more ▼]

Aphids are important pests of wheat and pea. Among the alternative methods to control them with less reliance on insecticides, crop associations already proved to be efficient. However, if increasing the chemical and structural complexity of vegetation can disrupt their host plants location, the searching efficiency of predators and parasitoids can also be reduced. Therefore, these beneficials may not always be more abundant in such systems. Combining crop associations with attractive semiochemicals for natural enemies can be interesting to solve this problem. In this research, we compared the effect of a wheat and pea pure stand, wheat and pea mixture, and wheat and pea mixture combined with methyl salicylate (MeSA) formulated in alginate gel beads, on the abundance and diversity of aphids and their natural enemies. These were weekly observed on plants during 2013 and 2014 growing seasons. Over these two years, significantly higher numbers of pea aphids (Acyrthosiphon pisum (H.)) were observed in the pure stand of pea compared with both mixtures (with and without MeSA). No significant differences were observed between treatments for wheat aphids (Sitobion avenae (F.), Metopolophium dirhodum (W.) and Rhopalosiphum padi (L.)), which were significantly less abundant than pea aphids. Aphid natural enemies were mainly observed on pea plants. Hoverfly larvae abundance was not significantly different between treatments during both years. The same phenomenon occurred with hoverfly pupae in 2013, while these were significantly more abundant in both mixtures compared with the pure stand in 2014. However, their number did not differ significantly between the mixture with and without MeSA. Few ladybirds and lacewings were observed. No significant differences were observed between treatments for parasitoid mummies in 2013. Their abundance was significantly higher in the pure stand of pea compared with both mixtures in 2014. Results from this study show that mixing wheat and pea is an efficient method to maintain aphid populations at a very low level on pea. The use of MeSA did not show significant effects on natural enemies. However, mixing these crops may be enough to reduce aphid populations under an acceptable threshold. [less ▲]

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See detailHow can an embryo become a prophet?
Swennen, Philippe ULg

Conference (2015, August 24)

Both Vedic and Avestan sacrifices show us how a sacrificer tries to make contact with his gods in the context of complex liturgical ceremonies implying the presence of priests who offer several kinds of ... [more ▼]

Both Vedic and Avestan sacrifices show us how a sacrificer tries to make contact with his gods in the context of complex liturgical ceremonies implying the presence of priests who offer several kinds of gifts, for instance poems, libations or slaughtered cattle. In both cases the religious doctrine justifying the liturgical process explains that the sacrificial ground and space correspond to the beginning of Time, but the definitions given to these beginnings are extremely divergent. This is surprising, because Indo-Iranian linguistics strongly suggests that both religious systems should be genetically very close. In Vedic India, the sacrificer represents an embryo, which should have been a god, but begets the human race. In Iran, he renews the first perfect ceremony achieved by Zarathushtra, the so-called prophet who chose to revere Ahura Mazda. How did one similar doctrine produce two so different products? [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 et al

Conference (2015, August 24)

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

Introduction: The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is a widespread invasive species damaging economically important solanaceous crop plants, including tomatoes and potatoes. Little is known about the ability of the 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. Objectives: 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. Materials and methods: For each plant species, fitness tests were performed in Petri dishes by isolating single individuals with excised leaf. Two choice behavioral assays were performed in flying tunnels. Volatile organic compounds released by solanaceous plants were trapped using a dynamic collection system, and analyzed by GC-MS. Results: 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 revealed that adult distribution and female oviposition did not differ between Solanum species, which were preferred to other tested solanaceous plants. The hypothesis that female host plant choice is influenced by plant volatile organic compounds was tested. 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. Conclusion: 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 detailSpecial seminar "Quaternary Prevention (P4) or First do not harm "
Jamoulle, Marc ULg; Widmer, Daniel; Wagner, Hamilton et al

Conference (2015, August 23)

Quaternary prevention (P4), an answer of family doctors facing overmedicalization aims to protect the patient or population against the dangers of medicine. Harmful effects can appear with preventive ... [more ▼]

Quaternary prevention (P4), an answer of family doctors facing overmedicalization aims to protect the patient or population against the dangers of medicine. Harmful effects can appear with preventive activities (example: prostate cancer screening by PSA) such as by therapeutic interventions (example: disruptive medicine). P4 promoted by the Wonca (World Organization of Family Doctors) is practiced in different ways around the world. The seminar should present examples of teaching and application of P4 in different countries. 6 short talks (total 45 min) will be followed by an open roundtable about the philosophical aspects of P4, where the audience can participate. Asking the question: « is acting always justified in medicine? », P4 opens our thinking to a philosophy of action. Questioning the best way to reduce uncertainty, P4 is rooted in a philosophy of knowledge. How to decide action or abstention? How to appreciate the danger of both? How to accompany a patient without harmful effects (primum non nocere)? More about P4 on www.ph3c.org/p4. [less ▲]

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See detail"Additive Layer Manufacturing for Space Instrumentation and subsystems"
Rochus, Pierre ULg

Conference (2015, August 22)

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See detailDissensus, Unclosure, and Agonistic Appraisal: Reconceiving of Technology Assessment and Consensus Conferences as Forms of Social Experimentation
Van Oudheusden, Michiel ULg

Conference (2015, August 20)

In this paper, I inquire into two public deliberative formats that aim to render scientific and technological practices more socially robust: the consensus conference and participatory technology ... [more ▼]

In this paper, I inquire into two public deliberative formats that aim to render scientific and technological practices more socially robust: the consensus conference and participatory technology assessment (pTA). Drawing on experiences in the US National Institute of Health Consensus Conferences and in a Flemish pTA on nanotechnologies, I make explicit how these formats enact a strong appeal to consensus; thereby delegitimizing conflict and disagreement among deliberating parties. By perceiving of these formats as social experiments that typically elicit undecided procedures and tentative, “unclosed” outputs, it is possible to: (a) pinpoint how conflict pervades deliberative engagements in science and technology, and (b) revalue conflict dynamics as a useful heuristic that encourages (rather than hampers) the expression of disagreement. I argue that deliberately seeking out conflict in deliberation is both morally responsible and epsitemically fruitful, as it obliges participants to refine their worldviews in confrontation with competing truth claims and enables them to articulate their personal or group needs. To further develop these lines of reasoning, I propose three conceptions that contrast with the consensus ideal: dissensus, unclosure, and (ant)agonistic learning. I conclude by offering suggestions on how to build critical reflection about the ethical, political, and epistemic implications of social experimentation into processes of science and technology governance. [less ▲]

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See detailPast and future distributions of Southeast Asian murine rodents: the influence of climate changes
Latinne, Alice ULg; Meynard, Christine; Morand, Serge et al

Conference (2015, August 18)

Our study, involving species distribution modelling techniques, aimed at assessing the influence of past and future climatic fluctuations on Southeast Asian small mammal distributions using two forest ... [more ▼]

Our study, involving species distribution modelling techniques, aimed at assessing the influence of past and future climatic fluctuations on Southeast Asian small mammal distributions using two forest-dwelling (Leopoldamys herberti and Leopoldamys sabanus) and one karst endemic (Leopoldamys neilli) rodent species as models. Our model predictions contradict the well-established hypothesis that Southeast Asian forest-dwelling species were confined to small refugia during the LGM. Moreover, these results suggest that the distribution of several East and Southeast Asian taxa were in their refugial state during Pleistocene interglacial periods rather than during glacial periods. This could be because of vegetation changes that may have occurred at that time as a result of the increased seasonality observed during the LIG. The two future climate change scenarios used in this study predicted that large climatically suitable areas would still be available in the future for the three species. [less ▲]

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See detailAGING MECHANISMS IN AMORPHOUS PHASE CHANGE MATERIALS
Raty, Jean-Yves ULg

Conference (2015, August 18)

Aging phenomena are common to all amorphous structures, but of special importance in phase change materials (PCM) since it impedes the realization of multi-level memories. Different interpretations have ... [more ▼]

Aging phenomena are common to all amorphous structures, but of special importance in phase change materials (PCM) since it impedes the realization of multi-level memories. Different interpretations have been proposed, but we focus here on the structural relaxation of amorphous GeTe, chosen because it is the simplest system that is representative of the wider class of GST alloys, lying along the GeTe-Sb2Te3 composition line of the GeSbTe phase diagram. The direct melt-and-quench DFT based Molecular Dynamics approach leads to models with a few hundred atoms, and, hence a small number of atomic environments. Here we sample a large number of local atomic environments, and bonding schemes, by chemically substituting different alloys to favor different local atomic structures. This enables spanning a larger fraction of the configuration space relevant to aging. GST alloys are known to display complex bonding that does not follow the chemist’s “octet-rule”. This lead to many controversies, especially concerning the local structure around Ge atoms. We overcome this problem by using state of the art non local DFT-MD, including the so-called van der Waals corrections. This leads to more clearly defined environments that are thoroughly analyzed. We can then identify their fingerprints in the available structural experimental data and assess their stability to find the driving forces leading to the structural relaxation. The calculated electronic properties nicely match the most recent photothermal deflection spectroscopy experiments. Our results support a model of the amorphous phase and its time evolution that involves an evolution of the local (chemical) order towards that of the crystal (by getting rid of homopolar bonds), and an evolution of its electronic properties that drift away from those of the crystal, driven by an increase of the Peierls-like distortion of the local environments in the amorphous [1]. [1] J.Y Raty, W. Zhang, J. Luckas, C. Chen, R. Mazzarello, C. Bichara and M. Wuttig, Nature Comm. To appear. [less ▲]

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See detailAtmospheric metal pollution over the last 250 years inferred from speleothem geochemistry
Allan, Mohammed ULg; Fagel, Nathalie ULg; Verheyden, Sophie

Conference (2015, August 17)

Lead concentrations and isotope ratios from two speleothems from the Han-sur-Lesse cave in southern Belgium were measured in order to study the ability of speleothems to act as archives of atmospheric ... [more ▼]

Lead concentrations and isotope ratios from two speleothems from the Han-sur-Lesse cave in southern Belgium were measured in order to study the ability of speleothems to act as archives of atmospheric pollution. To address this aim we analyzed trace elemental Al and Pb compositions by LA-ICP-MS and ICP-MS as well as Pb isotopes by MC-ICP-MS. The results help to identify three Pb-enriched intervals: from 1880 to 1905 AD, from 1945 to 1965 AD, and from 1975 to 1990 AD. The speleothem record is consistent with the evolution of atmospheric pollution in Belgium. Lead isotope ratios confirm that coal and gasoline combustion, combined with regional metallurgical activities, were the predominant Pb pollution sources in the stalagmites during the last 250 years. This research underscores the importance of speleothems as a valuable tool for the discrimination between anthropogenic and natural lead contributions in the environment and consequently for quantifying the anthropogenic contribution or determining natural background values in continental settings. [less ▲]

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See detailNi-Cu/SiO2 cogelled xerogel catalysts for selective hydrodechlorination of 1,2-dichloroethane into ethylene
Lambert, Stéphanie ULg

Conference (2015, August 13)

Hydrodechlorination of chlorinated organics is a particularly attractive alternative compared with incineration of wastes from the chlorine industry from both economic and environmental points of view ... [more ▼]

Hydrodechlorination of chlorinated organics is a particularly attractive alternative compared with incineration of wastes from the chlorine industry from both economic and environmental points of view. Several authors demonstrated the ability of bimetallic catalysts, composed of metals from Groups VIII and IB, to convert chlorinated alkanes selectively into less or not chlorinated alkenes. The purpose of this study is to measure catalytic activity and selectivities of 1,2-dichloroethane hydrodechlorination over Ni-Cu/SiO2 cogelled xerogel catalysts and to study relationships between catalytic activity and surface properties of bimetallic catalysts. To understand the mechanism of hydrodechlorination of 1,2-dichloroethane on a supported alloy, the surface composition of Ni-Cu alloy is measured from H2 chemisorption, XRD and TEM. Values obtained indicate a very pronounced surface enrichment with copper. Samples containing various amounts of nickel and copper are xerogels prepared by a one-step sol-gel procedure, which consists in the cogelation of the silica precursor, tetraethoxysilane (TEOS), with organically substituted alkoxides capable of forming chelates with nickel and copper ions. The resulting alcogels were dried under vacuum at 80°C, calcined in air at 400°C, and finally reduced in hydrogen at 450°C. For each catalytic experiment, 0.11 g of catalyst pellets were tested. The temperature was successively kept at 200, 250, 300, 350 and 300°C. While 1,2-dichloroethane hydrodechlorination over pure nickel mainly produces ethane, increasing copper content in bimetallic catalysts results in an increase in ethylene selectivity. Used alone, copper deactivates rapidly due to their covering by chlorine atoms. When nickel is present, it supplies hydrogen atoms for the regeneration of the chlorinated copper surfaces into metallic copper. The specific consumption rate of 1,2-dichloroethane decreases when copper loading increases. The turnover frequency, that is, the number of catalytic cycle per active site (nickel atom and its surrounding copper atoms) and per second, seems to be independent of surface composition of alloy particles. [less ▲]

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See detailLa presse vidéoludique francophone : formats (papier et numérique) et histoire
Dozo, Björn-Olav ULg

Conference (2015, August 11)

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See detailA principle of similarity for nonlinear vibration absorbers
Habib, Giuseppe ULg; Kerschen, Gaëtan ULg

Conference (2015, August 05)

With continual interest in expanding the performance envelope of engineering systems, nonlinear components are increasingly utilized in real-world applications. This causes the failure of wellestablished ... [more ▼]

With continual interest in expanding the performance envelope of engineering systems, nonlinear components are increasingly utilized in real-world applications. This causes the failure of wellestablished techniques to mitigate resonant vibrations. In particular, this holds for the linear tuned vibration absorber (LTVA), which requires an accurate tuning of its natural frequency to the resonant vibration frequency of interest. This is why the nonlinear tuned vibration absorber (NLTVA), the nonlinear counterpart of the LTVA, has been recently developed. An unconventional aspect of this absorber is that its restoring force is tailored according to the nonlinear restoring force of the primary system. This allows the NLTVA to extend the so-called Den Hartog’s equal-peak rule to the nonlinear range. In this work, a fully analytical procedure, exploiting harmonic balance and perturbation techniques, is developed to define the optimal value of the nonlinear terms of the NLTVA. The developments are such that they can deal with any polynomial nonlinearity in the host structure. Another interesting feature of the NLTVA, discussed in the paper, is that nonlinear terms of different orders do not interact with each other in first approximation, thus they can be treated separately. Numerical results obtained through the shooting method coupled with pseudoarclength continuation validate the analytical developments. [less ▲]

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See detailA propos des fonctions continues qui ne sont dérivables en aucun point
Esser, Céline ULg

Conference (2015, August 03)

En 1872, Karl Weierstrass présenta non seulement une, mais toute une famille de fonctions continues et nulle part dérivables. Après la publication de ce résultat, beaucoup d'autres mathématiciens ... [more ▼]

En 1872, Karl Weierstrass présenta non seulement une, mais toute une famille de fonctions continues et nulle part dérivables. Après la publication de ce résultat, beaucoup d'autres mathématiciens apportèrent leur propre contribution en construisant d'autres fonctions continues et nulle part dérivables. Dans cet exposé, nous présenterons les fonctions de Weierstrass et nous montrerons que le théorème de Baire permet d'affirmer que l'ensemble des fonctions nulle part dérivables est dense dans l'ensemble des fonctions continues. Nous étudierons également la régularité ponctuelle des fonctions de Weierstrass en introduisant la notion d'exposant de Hölder. [less ▲]

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See detailPulsations in hot subdwarf stars: recent advances and prospects for testing stellar physics
Charpinet, Stéphane; Van Grootel, Valérie ULg; Fontaine, Gilles et al

Conference (2015, August 01)

The evolved, core helium burning, extreme horizontal branch stars (also known as hot sudwarfs) host several classes of pulsators showing either p- or g-modes, or both. They offer particularly favorable ... [more ▼]

The evolved, core helium burning, extreme horizontal branch stars (also known as hot sudwarfs) host several classes of pulsators showing either p- or g-modes, or both. They offer particularly favorable conditions for probing with asteroseismology their internal structure, thus constituting arguably the most interesting seismic window for this intermediate stage of stellar evolution. G-modes in particular have the power to probe deep inside these stars, down to the convective He-burning core boundary where uncertain physics (convection, overshooting, semi-convection) is at work. Space data obtained with CoRoT and Kepler are offering us the possibility to probe these regions in detail and possibly shed new light on how these processes shape the core structure. In this review, I will present the most recent advances that have taken place in this field and I will provide hints of the foreseen future achievements of hot subdwarf asteroseismology. [less ▲]

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See detailTesting stellar opacities with laser facilities
Le Pennec, Maëlle; TURCK-CHIEZE, Sylvaine; RIBEYRE, Xavier et al

Conference (2015, August 01)

Helio and asteroseismology (SoHo, KEPLER...) have produced observed acoustic oscillations of thousands of stars which characteristics are deeply linked to the transport of radiation inside the stars ... [more ▼]

Helio and asteroseismology (SoHo, KEPLER...) have produced observed acoustic oscillations of thousands of stars which characteristics are deeply linked to the transport of radiation inside the stars. However, the comparisons of seismic data with model predictions have led to significant discrepancies, which could be due to a bad knowledge of production and transport of energy.β-Cephei are pulsating stars, progenitor of supernovae and thus deeply linked to our understanding of stellar medium enrichment. Their study has shown some difficulty to predict the observed oscillation modes, which are directly linked to an opacity bump of the elements of the iron group (Cr, Fe, Ni) at log T=5.25 (κ-mechanism). We will show that several parameters of the stars (mass, age, metallicity) have a great influence on the amplitude of the bump, which impact their structure. We will then present the final results of an experiment conducted at LULI 2000 in 2011 on Cr, Fe and Ni compared to several opacity codes. We will show how to improve the opacity in the range of temperature around log T= 5.3.The Sun is a privilege place to test and validate physics. Since the recent update of the solar composition, there is a well established large discrepancy (Turck-Chièze et al. 2001) between solar models and seismic data, visible on the solar sound speed profile comparison.An explanation could be that the calculations of energy transport are not correctly taken into account.Unfortunately, there are very few experiments to validate these calculations (Bailey et al. 2014). That's why we are proposing an opacity experiment on a high-energy laser like LMJ, in the conditions of the radiative zone. We are exploiting in that purpose an approach called the Double Ablation Front to reach these high temperatures and densities at LTE and validate or not plasma effects and line widths. We will show the principle of this technique and the results of our simulations on several elements.In the mean time, we are also exploiting new opacity calculations thanks to the OPAS code (Blancard et al. 2012) at the conditions of the solar radiative zone. We will show the impact of these calculations on the solar model. [less ▲]

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See detailOpacities in the massive stellar envelopes
Le Pennec, Maëlle; TURCK-CHIEZE, Sylvaine; Salmon, Sébastien ULg et al

Conference (2015, August 01)

Helio and asteroseismology (SoHo, CoRoT, KEPLER...) have produced observed acoustic oscillations of thousands of stars. The characteristics of these oscillations are deeply linked to the transport of ... [more ▼]

Helio and asteroseismology (SoHo, CoRoT, KEPLER...) have produced observed acoustic oscillations of thousands of stars. The characteristics of these oscillations are deeply linked to the transport of radiation inside the stars. However, the comparisons of seismic data of Sun and stars with model predictions have led to significant discrepancies, which could be due to a bad knowledge of production and transport of energy.We will focus here on the case of β-Cephei.β-Cephei are pulsating stars, progenitor of supernovae and thus deeply linked to our understanding of stellar medium enrichment. Their study has shown some difficulty to predict the observed oscillation modes, which are directly linked to a bump of the opacity of the elements of the iron group (Cr, Fe, Ni) at log T=5.25 through their pulsating mechanism called the κ-mechanism. We will show that the different parameters of the stars (mass, age, metallicity) have a great influence on the amplitude of the bump, and then on the structure of the considered star.The mastery of the κ-mechanism that produces the pulsation of these stars supposes a fine determination of the peak opacity of the iron group in their envelope. We will present the final results of an experiment conducted at LULI 2000 in 2011 on Cr, Fe and Ni and compare them to OP and ATOMIC, SCO-RCG codes. We will show how to improve the opacity in the range of temperature around log T= 5.3. [less ▲]

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See detailSinging accuracy, listeners’ tolerance, and pitch analysis
Larrouy, Pauline ULg; Devaney, Johanna

Conference (2015, August)

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See detailListeners’ tolerance when listening to melodic performances
Larrouy, Pauline ULg; Gosselin, Laura; Blanckaert, Ellen ULg et al

Conference (2015, August)

A melodic performance can be slightly out of tune (i.e., enlargement or compression of an interval of ~20 cents) and still be rated as “in tune” by layman listeners. In order to elucidate the concept of ... [more ▼]

A melodic performance can be slightly out of tune (i.e., enlargement or compression of an interval of ~20 cents) and still be rated as “in tune” by layman listeners. In order to elucidate the concept of pitch accuracy in melodies, this study aims (a) to clarify the effect of music expertise when listening to familiar vs. non-familiar melodies and (b) to quantify the perceptual thresholds of music experts when listening to melodic performances. For (a), familiar and non-familiar melodic sequences were manipulated, from “in tune” (deviation of 0 cent) to “out of tune” (10 to 60 cents, in 10 cent steps). The sequences were presented to 30 non-musicians and 30 musicians, matched in age and gender, using the method-of-limits procedure, in a test/retest paradigm. For each condition, participants were asked to specify whether the presented singing performances were “in tune” or “out of tune”. For (b), the same melodies, with smaller manipulations (0 to 30 cents, in 5 cent steps), were presented to 30 musicians using the same procedure. We observed a high test – retest reliability, independent of both familiarity of melody and musical training. As expected, there was an effect of expertise (p < .001) on the perceptual thresholds (experts’ tolerance of ~10 cents). In addition, we observed a specific profile for music experts, who were particularly sensitive to interval compressions. This study yields the opportunity to refine objective tools for the evaluation of singer pitch accuracy but also to provide pertinent material to investigate the music perception process. [less ▲]

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See detailNew insight in lymnaeid snails (Mollusca, Gastropoda) as intermediate hosts of Fasciola hepatica (Trematoda, Digenea) in Ecuador
Caron, Yannick ULg; Celi-Erazo, Maritza; Hurtrez-Boussès, Sylvie et al

Conference (2015, August)

Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts are scarce in Ecuador. During 3 months, lymnaeid snails were ... [more ▼]

Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts are scarce in Ecuador. During 3 months, lymnaeid snails were sampled (n=1482) in Pichincha province in two sites located in a highly endemic area. The snails were identified (based on morphology and ITS2 sequences) and the infection status was established through microscopic dissection and a multiplex PCR-based technique. If morphologic-based techniques were not useful to accurately named the one species collected, alignment study ascribed it to L. schirazensis. Rediae were observed in 1.75 % (26/1482) and Fasciola sp. DNA was detected in 6% (89/1482) of the collected snails. The COX1 region permitted the parasite species identification: F. hepatica. The relative sensitivity and specificity of the microscope related to the PCR results was 25.84% and 99.78% respectively. The mean size of the snails recorded positive for F. hepatica through crushing and microscopy was significantly higher than the mean size of negative snails. There was not such difference in PCR positive snails. The role of G. schirazensis as an intermediate host of F. hepatica in Ecuador is discussed and a hypothesis of an adaptation of the snail to the trematoda is formulated. For the first time, an epidemiological survey, based on molecular biology-based techniques assessed the role of lymnaeid snail in the epidemiology of fasciolosis in Ecuador. [less ▲]

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See detailHow can phenology contribute to ecological restoration?
Buisson, Elise; Alvarado, Swanni; Le Stradic, Soizig ULg et al

Conference (2015, August)

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See detailSpecies-rich anthropogenic grasslands and the problem of afforestation
Buisson, Elise; Le Stradic, Soizig ULg; Alvarado, Swanni et al

Conference (2015, August)

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See detailCritical role of oxygen photoreduction downstream of PSI in Symbiodinium: photoprotection, energetic adjustement and ROS production
Roberty, Stéphane ULg; Bailleul, Benjamin; Berne, Nicolas ULg et al

Conference (2015, August)

The ecological success of symbiotic cnidarians (reef building-corals and sea anemones) relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium ... [more ▼]

The ecological success of symbiotic cnidarians (reef building-corals and sea anemones) relies on the symbiosis between cnidarians and photosynthetic dinoflagellates of the genus Symbiodinium. Photosynthetic organisms have evolved various photoprotective and regulatory mechanisms to cope with changing and high light intensities, but the nature and relative amplitude of these mechanisms is still a matter of debate in Symbiodinium. Few studies showed that molecular oxygen (O2) can be an efficient electron sink during photosynthesis in Symbiodinium, with an O2 uptake capacity that could represent up to half the maximum O2 evolution. In addition, members of clade A Symbiodinium were proposed to possess enhanced capabilities for alternative photosynthetic electron flows. In this work, the amplitude of photosynthetic alternative electron flows to oxygen (chlororespiration, Mehler reaction, mitochondrial respiration) and PSI cyclic electron flow were investigated in Symbiodinium strains belonging to different Clades (A, B and F). Joint measurements of oxygen evolution, PSI and PSII activities allowed us to demonstrate that photoreduction of oxygen downstream PSI by the so-called Mehler reaction is the main alternative electron sink at the onset and steady state of photosynthesis in all strains1. This mechanism in Symbiodinium sustains significant photosynthetic electron flux under high light, thus acting as a photoprotective mechanism and modifying the ratio of ATP/NADPH to match the requirements of carbon reduction. At higher temperature (26 to 33°C), the amplitude of Mehler reaction was still significantly increased but the capacity of enzymes responsible for superoxide detoxification largely decreased. This imbalance generated twice more ROS than during the treatment at 26°C, suggesting that under conditions known to induce coral bleaching, the photoprotective role of Mehler reaction can no longer be maintained, at least at short term. [less ▲]

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See detailMid-winter surveys for sea ice biogeochemistry in bi-polar oceans
Nomura, D.; Delille, Bruno ULg; Dieckmann, G. et al

Conference (2015, August)

Sea ice has rarely been considered in estimates of global biogeochemical cycles, especially gas exchanges, because of the assumption that, in ice-covered seas, sea-ice acts as a barrier for ... [more ▼]

Sea ice has rarely been considered in estimates of global biogeochemical cycles, especially gas exchanges, because of the assumption that, in ice-covered seas, sea-ice acts as a barrier for atmosphere–ocean exchange. However, recent work has shown that sea ice and its snow cover play an active role in the exchange of gases between the ocean and atmosphere [1] [2]. Our results provide a useful reference for future studies as the ongoing drastic changes in polar climate and sea ice extent are likely to alter the biogeochemical cycles in polar ocean–sea ice–atmosphere system. However,, the lack of information for the winter-time sea ice biogeochemistry was pointed out, due to the difficulty to acquire data under harsh weather conditions. In this presentation, we will present our recent winter-time sea ice surveys of sea ice biogeochemistry on the R/V Aurora Australis off East Antarctica (SIPEX-II) in 2012 and the midwinter sea ice cruise on the R/V Polarstern in the Weddell Sea, Antarctica (AWECS) in 2013. In addition, we will also show the ongoing project of Norwegian Young sea ICE cruise (NICE2015) on the R/V Lance drifting for half a year in Arctic sea ice north of Svalbard in 2015. [1] Nomura et al. (2013) J. Geophys. Res. Oceans 118, 6511- 6524. [2] Delille et al. (2014) J. Geophys. Res. Oceans 119, 6340-6355. [less ▲]

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See detailLate-Holocene tropical moist-forests of southeastern Cameroon: some insight from soil charcoal analysis
Morin, Julie ULg; Biwolé, Achille; Bourland, Nils et al

Conference (2015, August)

Tropical forests of Central Africa constitute the second most important block of moist forest of the world. Little is known, however, about past vegetation in this region that remains underexplored ... [more ▼]

Tropical forests of Central Africa constitute the second most important block of moist forest of the world. Little is known, however, about past vegetation in this region that remains underexplored (Vleminckx et al. 2014; Morin-Rivat et al. 2014). Determining the past specific composition of these forests could allow bringing insights into their evolution over time and providing data about their resilience capacity facing global change. We performed a pedoanthracological analysis in the semi-deciduous forests of southeastern Cameroon. We excavated 53 test pits of 53 50 × 50 × 60 cm in plots of botanical inventory along a NS 80-km long mega-transect that followed a vegetation gradient. We sorted and quantified charred macrobotanical remains by layers of 10 cm, then identified species from wood charcoals. We used the InsideWood database, implemented with 163 new anatomical descriptions of woods present in the study area by using the reference collection of African woods of the Royal Museum for Central Africa (Belgium). Finally, we obtained 25 radiocarbon dates on charcoals and oil palm endocarps. Results showed that repeated fire events occurred across the study area during the last 2500 years, soon after the well-documented “rainforest crisis” (e.g. Lézine et al. 2013). The analyzed charcoals are likely human-induced regarding evidence of associated human settlements (e.g. potsherds). Aged were distributed into two time periods: the Early Iron Age (2300-1300 BP) and the Late Iron Age (700-100 BP) with an intermediate hiatus in human occupation (see e.g. Wotzka 2006; Morin-Rivat et al. 2014). Specific composition during both periods did not strongly differ from current composition, which is now dominated by light-demanding canopy trees belonging to old-growth semi-deciduous Celtis forests (Gond et al. 2013; Fayolle et al. 2014). This argues in favor of the maintenance of light-demanding tree species by anthropogenic activities, such as slash-and-burn shifting cultivation. We conclude that moist forests have a good resilience capacity regarding moderate and scattered disturbances. These forests can nonetheless be deeply impacted by land-use intensification (e.g. degraded forests along roads and close to cities; Gond et al. 2013). [less ▲]

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See detailLes carrières des cadres : regard croisé du sexe (genre) et de l'âge (générations).
Grodent, Françoise ULg; Cornet, Annie ULg

Conference (2015, August)

Ce papier a pour objectif la construction d'une grille d'analyse destinée à comparer les trajectoires professionnelles des hommes et des femmes cadres issus de trois groupes d'âge différents, à savoir les ... [more ▼]

Ce papier a pour objectif la construction d'une grille d'analyse destinée à comparer les trajectoires professionnelles des hommes et des femmes cadres issus de trois groupes d'âge différents, à savoir les moins de 35 ans, les [35-50] ans et les plus de 50 ans. Le fait d’introduire la dimension de l'âge, en plus de celle du sexe, s’appuie sur la notion d’intersectionnalité qui vise à analyser la manière dont se combinent différentes caractéristiques de la diversité (ici le genre et l’âge) dans les trajectoires professionnelles des cadres. L’âge a été découpé en trois groupes de manière arbitraire, cela dans l’idée d’avoir trois catégories d’âge qui cohabitent actuellement et à la même période dans l’entreprise. Ces trois dernières peuvent recouper certaines générations, porteuses de diverses valeurs et représentations qui renvoient notamment aux rôles attribués aux hommes et aux femmes ainsi qu'à certaines attentes quant aux comportements de l’un et l’autre sexe. Cette comparaison intergénérationnelle nous permettra de mobiliser les théories du genre, à savoir les constructions socio-culturelles du féminin et du masculin, les rôles attribués aux femmes et aux hommes ainsi que les rapports sociaux entre les sexes, enracinés dans leur contexte historique. L’objectif est de proposer une grille de lecture qui sera utilisée pour l’analyse de données tant quantitatives que qualitatives collectées dans le cadre d'une thèse en cours de finalisation. Ce travail s’appuie sur une approche abductive, à savoir sur la volonté de faire des allers et retours entre des grilles d’analyse théoriques et des données inductives, utilisées à leur tour pour questionner et affiner les grilles d’analyse proposées. [less ▲]

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See detailHabitat use of the endangered Lepilemur mittermeieri - Northwest Madagascar
Wilmet, Leslie ULg; Vermeulen, Cédric ULg; Beudels-Jamar, Roseline C et al

Conference (2015, August)

Genus Lepilemur is exemplary of the endemic mammalian fauna of the island of Madagascar. Sportive lemurs have small distribution ranges, and fairly small total populations and are particularly negatively ... [more ▼]

Genus Lepilemur is exemplary of the endemic mammalian fauna of the island of Madagascar. Sportive lemurs have small distribution ranges, and fairly small total populations and are particularly negatively affected by deforestation and habitat fragmentation. Our research focus on a poorly-known taxon, Lepilemur mittermeieri, whose distribution range is located on the Ampasindava peninsula in the northwest Madagascar. It has been described in 2006 on the basis of genetic material only. Since then, no further research has been conducted and general information of this endangered species is urgently requested. We will present our global project as well as the results of a second field mission conducted from March to June 2015 in order to specifically 1) investigate habitat use of 8 radio-collared Lepilemur mittermeieri by the analysis of their home range, feeding ecology and sleeping sites characteristics and 2) to complete forest characterization of the home range of each radio-collared animal. This study is conducted on the Ampasindava peninsula, a priority area for Malagasy conservation. [less ▲]

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See detailHow do “scoops” influence the perception of singing accuracy?
Larrouy, Pauline ULg; Pfordresher, Peter

Conference (2015, August)

When we listen to a singer, a large amount of time-varying information is available on which evaluations of accuracy may be based. Most analyses of singing accuracy focus on relatively steady portions of ... [more ▼]

When we listen to a singer, a large amount of time-varying information is available on which evaluations of accuracy may be based. Most analyses of singing accuracy focus on relatively steady portions of sung notes, eliminating “scoops” of pitch that often occur at note beginnings and endings. However, it is likely that these scoops contribute to judgments of accuracy. We report results of three experiments designed to address the relative contribution of these scoops in contrast to a steady central portion of sung notes. Participants rated the pitch accuracy of 4-tone melodies where the 3rd tone was manipulated with respect to its center region (either correct, 50 cents sharp, or 50 cents flat) as well as the presence of a scoop at the start and/or the end of the tone, varying with respect to direction. We were particularly interested in contrasting scoops that maintained ‘continuity’ between tones (e.g., scooping up for an ascending interval) versus those that highlighted distinctions (the opposite). Further analyses evaluated whether reactions to scoops indicate a tendency to perceive the average pitch across the entire tone, or to treat scoops versus the tone’s center as separate features. Results suggest that listeners respond to scoops in a way that goes beyond role in forming the average pitch across a tone. Listeners respond differently to scoops at the beginning versus the end, showing more sensitivity to ending scoops. Furthermore, listeners do not necessarily prefer scoops that preserve continuity. Taken together, these results demonstrate that continuous time-varying pitch information is an important indicator of perceived singing accuracy, and should be considered more fully when assessing singing ability. [less ▲]

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See detailNiche-innovations between breaks and continuities with the regime? A case study into the dairy sector in Belgium
Feyereisen, Marlène ULg; Melard, François ULg; Stassart, Pierre M ULg

Conference (2015, August)

Today, the absolute dichotomy between alternative food networks (AFNs) and the conventional agrofood system tends to be obsolete. Indeed, many AFNs are far from being radical and are more likely to ... [more ▼]

Today, the absolute dichotomy between alternative food networks (AFNs) and the conventional agrofood system tends to be obsolete. Indeed, many AFNs are far from being radical and are more likely to maintain relations with the current socio-technical regime between breaks and continuities. This contribution is a complement to the Transition Theory and the Multi-Level Perspective by underlying the fragile borders between the two levels of the niche-innovations and the socio-technical regime: some imperfect projects, full of contradictions, are participating to the transition of the system. And this is particularly true in the case of highly locked in systems. The dairy sector in Western European countries is one of those highly locked in systems. Our case study, the Belgian fair-trade milk “Fairebel”, is a project built by dairy farmers to react to the 2009 dairy crisis and to the increasingly neoliberal dairy sector; and to get a better price (or fair price) for their activity. However, the concretization of this project brought its share of contradictions regarding the common definition of fair trade milk. As a result, the “Fairebel” project maintains relations between breaks and continuities with the regime. This contribution suggests modes of governance for the stakeholders of these non-radical niches which are precious to engage change in highly locked in system without being picked up by the dominant regime and thus, keep this regime under pressure. [less ▲]

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See detailCONTRIBUTION OF ION MOBILITY FOR STRUCTURAL ANALYSIS AND ANALYTICAL CHEMISTRY: THE USE OF PROBE LIGANDS AND SELECTIVE IMS SHIFT REAGENTS
Kune, Christopher ULg; Far, Johann ULg; Delvaux, Cédric ULg et al

Conference (2015, July 28)

Ion mobility is a gas phase separation technique sensitive to the Collisional Cross Section (CCS) difference of ions (as CCS/ΔCCS). It discriminates isobaric and isomeric ions when CCS difference is ... [more ▼]

Ion mobility is a gas phase separation technique sensitive to the Collisional Cross Section (CCS) difference of ions (as CCS/ΔCCS). It discriminates isobaric and isomeric ions when CCS difference is larger than the instrumental resolution (roughly 50). To overcome the usual resolution of ion mobility (IM), it is necessary to use new strategies in addition to the optimization of the ion mobility parameters. This work proposes a new method to bypass this limitation while providing additional structural information by the use of Selective Shift Reagents (SSR). A SSR can specifically bind with a target ion depending of their physicochemical properties like chemical groups, steric hindrance, polarity, space charge effects… In this strategy, the choice of SSR is fundamental. SSR could be empirically selected or assisted and designed by computational chemistry prediction. SSR can be used as a chemical probe which can support physicochemical properties and help or confirm hypotheses for structural elucidation. They can also drastically change the CCS of a target ion present in a complex mixture (e.g. biological origin sample) as shifting reagent for e.g. quantification purpose. Models used for the proof of concept have been selected in order to lead to an expected or predictive result. Firstly crown ethers have been used as SSR in IMS to shift the protonated valine drift time from the protonated proline drift time according to their chemical groups and especially amino groups. The selectivity of SSR leads to an improved separation between valine and proline. Secondly three structural isomers of diaminonaphthalene were investigated experimentally and theoretically using computational chemistry support after the addition of different crown ethers or β-cyclodextrin as SSR to improve the separation of these isomers by IMS. Finally, the concept of SSR was successfully applied to biological origin samples to elucidate structure and allows the quantification of selenium (Se) containing compounds present in an aqueous extract of Se rich yeast. [less ▲]

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See detail« Rien dans tout cela où ne soit Zeus ». L'eau du ciel, un domaine exclusivement jovien ?
Lebreton, Sylvain ULg

Conference (2015, July 23)

Si les anciens Grecs ont donné en partage leurs paysages aquatiques – sources, fleuves et rivières, mers et océans – à un grand nombre de divinités différentes, il semble bien qu'ils faisaient de Zeus le ... [more ▼]

Si les anciens Grecs ont donné en partage leurs paysages aquatiques – sources, fleuves et rivières, mers et océans – à un grand nombre de divinités différentes, il semble bien qu'ils faisaient de Zeus le seul dieu compétent en ce qui concerne la pluie. Depuis le « Zeus pleut » homérique, la littérature grecque abonde en effet de témoignages suggérant ce rapport d'exclusivité. Sans prétendre changer fondamentalement la donne, une analyse des données cultuelles – à partir des sources épigraphiques notamment – permettra sans doute de préciser, d'ajuster cet état de fait qui semble de fait souffrir de bien peu d'exceptions. Un examen systématique des nombreuses épiclèses « pluvieuses » du polythéisme hellénique tend en effet à confirmer le caractère spécifiquement jovien de ce domaine de compétence – les autres divinités ne semblant y intervenir qu'à ses marges (Apollon et la grêle par exemple). Mais le constat de la richesse et de la diversité de ces épithètes cultuelles constitue surtout le marchepied nécessaire à une réflexion sur les fondements et les modalités des adresses des Grecs à leurs dieux – leur Zeus en l'occurrence – pour tenter de gérer au mieux l'eau du ciel. Une étude exhaustive de ces épiclèses et des données cultuelles qui leur sont associées permet en effet de souligner en outre les spécificités de ce champ de compétence divin, dans le temps – à la fois sur le plan du temps rituel, mais aussi des évolutions depuis l'époque archaïque jusqu'à la période impériale – comme dans l'espace. Sur ce dernier point en effet, force est de constater que les épiclèses pluvieuses de Zeus ont partie liée à l'emprise spatiale du dieu, sommitale en l'occurrence. Plus globalement, elles ne se limitent pas à ce strict domaine d'intervention ; inversement, d'autres épithètes non explicitement pluvieuses peuvent aussi désigner le Zeus faiseur de pluie. Ainsi, ces épiclèses se trouvent au sein d'un réseau de champs de compétences joviens qui ne sont pas isolés, mais bien articulés les uns aux autres. Et c'est dans ce réseau qu'il est possible de déceler, in fine, la cohérence de cette construction culturelle qu'est Zeus. Sans pouvoir prétendre aborder l'ensemble des conceptions grecques en matière de pluie, ce parcours à travers les épiclèses pluvieuses de Zeus permettra néanmoins d'évoquer quelques dossiers relevant tant du rite (cas de la danse de la pluie, cadres rituels, calendaires par exemple), que de la pluviométrie (précipitations et sécheresse) ou encore de l'agriculture, le tout s'inscrivant dans les récents débats conceptuels relatifs à la cohérence du polythéisme. Compte tenu de sa richesse, la documentation attique sera privilégiée, sans toutefois négliger les parallèles extra-athéniens, depuis l'époque archaïque jusqu'au Haut-Empire. [less ▲]

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See detailImpact of phenotypic heterogeneity and metabolic specialisation on metabolic engineering strategies: case of study of E.coli as a representative microbial cell factory
Brognaux, Alison ULg; Delepierre, Anissa ULg; Pecheux, Hélène ULg et al

Conference (2015, July 21)

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant ... [more ▼]

The goal of this research is to directly highlight the simultaneous occurrence of several phenotypes with distinct metabolic function among clonal population of E. coli., often used for recombinant protein and pDNA production in bioprocesses. This phenotypic heterogeneity, first due to the noise, is reinforced by environmental heterogeneities occurring at large scale during fed-batch processes. This phenotypic heterogeneity has been tracked according to GFP reporter strains (biosensors) that circulate in the bioreactor and encounter environmental heterogeneities. First, we have highlighted the simultaneous occurrence of several phenotypes with distinct metabolic functions. Indeed, a diversity of glucose uptake strategies has recently been noticed with the PtsG and MglABC transporters. Moreover, when E.coli encounters zones of glucose excess, acetate is produced through the overflow metabolism. Only the sub-population with high acs expression (acetate transporter) could consume this acetate. GFP reporter strains have thus been constructed for PtsG, MgIABC and acs genes. In addition of the stable GFP, two destabilized GFP variants for each gene have been used to obtain more instantaneous responses. The response of these biosensors have been followed by on-line flow cytometry. In the end, this experimental strategy for direct phenotyping at the single cell level will also be used to investigate the impact of metabolic engineering strategies on phenotypic heterogeneity, robustness and fitness of microbial population in industrial conditions. [less ▲]

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See detailFunctionality of microbial phenotypic heterogeneity in bioprocessing conditions: an analysis based on the use of on-line flow cytometry
Delepierre, Anissa ULg

Conference (2015, July 20)

Microbial phenotypic heterogeneity is known to be naturally present in isogenic population and can be attributed to the stochastic nature of the biochemical reactions. An important question at this level ... [more ▼]

Microbial phenotypic heterogeneity is known to be naturally present in isogenic population and can be attributed to the stochastic nature of the biochemical reactions. An important question at this level was to determine whether such stochastic behavior exhibits some functionality, i.e. how single cell heterogeneity leads to population level strategies. One of this strategies, called bet-hedging, is known to give a competitive advantage to the population, by leading for example to a persistent phenotype able to survive to antibiotics exposure. Among the single cell toolbox available for the analysis of phenotypic heterogeneity, flow cytometry present the advantage of being compatible with bioprocess cultivation tools. In this work, we present an on-line analytical workflow based on automated flow cytometry that can be used to monitor simultaneously several bioreactors, testing different bioreactor operating conditions, in combination with fluorescent transcriptional reporter strategies: promoter involved in metabolism fused to a gene expressing an unstable variant of GFP , and viability fluorescent tagging: propidium iodide uptake, correlated with membrane permeability. [less ▲]

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See detailTowards an "African Stylistics": Apprehending Cross-Cultural Creativity in the Works of Chris Abani
Tunca, Daria ULg

Conference (2015, July 18)

Anglophone African literatures have often been praised for their linguistic originality. More often than not, critics interested in the stylistic inventiveness of works from the continent have focused ... [more ▼]

Anglophone African literatures have often been praised for their linguistic originality. More often than not, critics interested in the stylistic inventiveness of works from the continent have focused their attention on these texts’ specifically “African” features, from the use of proverbs to the presence of words from indigenous languages. While these scholarly studies have done much to demonstrate the richness of African aesthetic standards, they have also tended to obscure other facets of the creativity of African writers who, just like their counterparts all over the world, make ample use of such devices as metaphor, irony, and unreliable narration. After a brief examination of the methodological and epistemological issues that have shaped the elusive field of “African stylistics”, I propose to investigate how contemporary stylistic theories may contribute to the understanding of the multiple forms of creativity found in the works of the US-based Nigerian writer Chris Abani. A self-proclaimed “global Igbo” (after the name of his father’s ethnic group), Abani boldly combines in his work African cosmology with influences from the Catholic and Buddhist traditions, also using formal devices – such as minor sentences and poetic metaphors – whose significance can only be fully appreciated through extensive stylistic analysis. Mainly focusing on Abani’s novella Becoming Abigail (2006), I will suggest that a combination of traditional culture-oriented approaches to African literatures and more typically “mainstream” stylistic techniques is needed to apprehend the Nigerian writer’s complex cross-cultural worldview. [less ▲]

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See detailVirtual plaster cast: digital 3D modelling of paws and tracks via photogrammetry
Marchal, Antoine ULg; De Bruyn, Nico; Lejeune, Philippe ULg

Conference (2015, July 17)

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See detailBranch-and-Price Based Matheuristics for a Vehicle Routing Problem with Time Windows and Variable Service Start Time
Küçükaydın, Hande; Arda, Yasemin ULg; Crama, Yves ULg et al

Conference (2015, July 15)

We investigate a vehicle routing problem with time windows (VRPTW), where the drivers are paid per time unit worked and the starting times of their shifts are to be determined by the decision maker. In ... [more ▼]

We investigate a vehicle routing problem with time windows (VRPTW), where the drivers are paid per time unit worked and the starting times of their shifts are to be determined by the decision maker. In order to solve the problem to optimality, a branch-and-price (BP) algorithm is implemented recognizing the pertinent pricing subproblem as an elementary shortest path problem with resource constraints (ESPPRC) which can handle an infinite number of labels and employs effective dominance rules. We present the past, present, and future implementations of the BP procedure based on bounded bi-directional search, decremental state space relaxation, and ng-route relaxation. We further discuss the design of BP-based matheuristics which make use of metaheuristics in pricing subproblem resolution, upper bound improvement, and column generation. [less ▲]

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See detailA general lotsizing problem with uncertain product returns
Amand, Guillaume ULg; Arda, Yasemin ULg

Conference (2015, July 15)

We consider a single-stage system that produces a range of final products. The demands of the final products are supposed deterministic over a finite planning horizon. Each unit of demand has to be ... [more ▼]

We consider a single-stage system that produces a range of final products. The demands of the final products are supposed deterministic over a finite planning horizon. Each unit of demand has to be fulfilled at the period that it appears using either the production of that period or the inventory carried over from the earlier periods. The final products can either be manufactured using purchased materials or remanufactured using remanufacturable returned products. For each final product, the manufactured and remanufactured items are perfectly substitutable. The returned products are collected at the start of each period but the quantities obtained are unknown until the collection. The return inventories accumulate as remanufacturable returned items are received. The manufacturing and remanufacturing processes of all the final products are executed on a same machine. In each time period, multiple products can be processed but the total production quantity is limited by the time availability of the machine during this period. Whenever production is switched from one final product to another, a sequence dependent setup cost is incurred and a sequence depen- dent setup time is consumed from the available time capacity. Different stochastic combinatorial optimization methods as well as dynamic programming methods are proposed, tested and compared. [less ▲]

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See detailEffect of calving interval on the economic results of dairy farms based on their typology.
Dalcq, Anne-Catherine ULg; Beckers, Yves ULg; Wyzen, Benoit et al

Conference (2015, July 15)

The calving interval (CI) can influence the milk production (MP) and the economic results of a farm. This research aimed to highlight the most economically important CI, on the basis of the accounts of ... [more ▼]

The calving interval (CI) can influence the milk production (MP) and the economic results of a farm. This research aimed to highlight the most economically important CI, on the basis of the accounts of breeders. The data set contained 1,318 accounts spread between 2007 and 2012. Technical information such as mean CI of the herd, percent of cows with a CI of less than 380 d (m380), between 380 and 419 d (e380419), between 420 and 459 d (e420459) and more than 459 d (p459), mean MP of the herd; as well as typological information such as quantity of equivalent concentrate (CC), number of ares of grass (GR) and of corn silage (CS) per livestock unit (LU); and economic information such as mean gross margin per cow were available. The relation between CI and the gross margin showed that if a single economic optimum of CI cannot be determined, this optimum could depend on the typology of the farm. Therefore, 4 groups were created by using a multiple correspondence analysis, including quantity of equivalent CC, number of ares of GR and of CS per LU as variables. The first group was the most intensive one with a feeding based mostly on CC and CS; the second group was similar but less intensive. The third group was the most extensive with high GR consumption. The fourth group was characterized by a near absence of CS but more CC. Moreover, m380, e380420, e420459, p459 were transformed from quantitative to qualitative variables by using numerical classification. A qualitative variable CI profile was created as a summary of all these variables. In each group, MP was modeled using the different CI variables. The assumption behind this modeling was that for a typological profile, the breeder must have the highest MP to maximize the gross margin. These models showed that MP is maximized when p459 is lower than 26%, lower than 37%, above 27% for the group 1, 2, 3 respectively. For the group 4, the model with the variable CI profile suggested that the economic optimum of CI is intermediate. These results underlined that the economic optimum of CI is related to the typology of the considered farm. Studying individual data is a perspective to determine more precisely CI with the best economic results. [less ▲]

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See detail«Aménager un environnement : bienveillance et non-vouloir»
Brahy, Rachel ULg; Servais, Véronique ULg

Conference (2015, July 14)

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See detailPersonnalité antisociale et psychopathologie
Englebert, Jérôme ULg

Conference (2015, July 14)

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes ... [more ▼]

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes contradictions propres au diagnostic qui nous mèneront à l’identification du critère « primaire » de cette entité qui est l’« incapacité à se conformer aux lois et normes sociales ». Nous confronterons ensuite à des situations cliniques l’hétérogénéité des profils pouvant répondre à ce diagnostic. Nos constats nous conduiront à mettre en doute la validité apparente du concept de personnalité antisociale, puisqu’il recouvre des modes de fonctionnement psychologique variés. La valeur discriminative faible, en matière de fonctionnement psychologique, suggère que c’est une dimension autre que psychopathologique qui organise ce diagnostic. Dénuée de toute attention pour les modes d’interactions, pour le vécu émotionnel et pour les états de subjectivité, la notion de personnalité antisociale ne porte pas d’intérêt à l’individu qu’elle catégorise, mais bien à l’acte délinquant commis par ce dernier. Nous conclurons sur le constat de l’absence de dimension psychopathologique de la personnalité antisociale, qui se révèle être un diagnostic principalement criminologique, à l’inverse des fondements de l’éthique psychopathologique. [less ▲]

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See detailEvolutionary drivers of species delimitation in African polyploid complex trees genus Afzelia: insights from molecular phylogeny
Donkpegan, Segbedji ULg; Duminil, Jérôme; Daïnou, Kasso ULg et al

Conference (2015, July 13)

Background:. Molecular markers can improve our knowledge of the rain forest biodiversity, especially to decipher species evolution and delimitation within genera. In this study, we investigated ... [more ▼]

Background:. Molecular markers can improve our knowledge of the rain forest biodiversity, especially to decipher species evolution and delimitation within genera. In this study, we investigated evolutionary relationships among the Afzelia genus, an important tropical timber taxon in Africa.. Method: We used nuclear and chloroplast DNA associated with partial plastome sequences data to infer phylogenetic relationships among the six broadly distributed species of the genus: A. africana and A. quanzensis (savannah species), A. bipindensis, A. bella, A. pachyloba and A. parviflora (forest species). Using microsatellite markers (SSR), we also applied a clustering analysis (STRUCTURE) to verify whether the current taxonomic species delimitation matches the biological species concept. Result and discussion: Our SSR data showed for the first time that savannah species were diploid while forest species were tetraploid. Nuclear DNA separates diploid and tetraploid species in two distinct cladesbut plastid markers show that one diploid species forms a well-supported clade with the tetraploids, suggesting historical hybridization, possibly in relation with genome duplication (polyploidization) and habitat shift from dry to rain forests. The genetic structure observed with SSR confirms the taxonomic delimitation of the two diploid species and one tetraploid species (A. pachyloba). It also suggests the existence of a single Afzelia forest species in West Africa, and the presence of two distint species within the A. bipindensis taxon, with potential hybridization with A. bella. Conclusion: The evolutionary history of the genus Afzelia is complex and the potential link between polyploidization and habitat shift needs further investigation. Our data also show that species delimitation must be revisited, at least among three of the four rain forest species. [less ▲]

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See detailFeasibility-oriented Branching Strategies for Global Optimization
Gerard, Damien ULg; Köppe, Matthias; Louveaux, Quentin ULg

Conference (2015, July 13)

We study the spatial Brand-and-Bound algorithm for the global optimization of nonlinear problems. In particular we are interested in a method to find quickly good feasible solutions. Most spatial Branch ... [more ▼]

We study the spatial Brand-and-Bound algorithm for the global optimization of nonlinear problems. In particular we are interested in a method to find quickly good feasible solutions. Most spatial Branch-and-Bound-based solvers use a non global solver at a few nodes to try to find better incumbents. We show that it is possible to improve the branching rules and the nodes priority by exploiting the solutions from the non global solver. We also propose several smart adaptive strategies to choose when to run the non global solver. We show that despite the time spent in solving many more NLP problems in the nodes, the new strategies enable the algorithm to find the first good incumbents much faster and to prove the global optimality faster. NLP instances from the COCONUT library are benchmarked. All experiments are run using the open source solver Couenne. [less ▲]

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See detailEthnopharmacology and malaria in Africa
Frederich, Michel ULg; Jansen, Olivia ULg; Muganga, raymond et al

Conference (2015, July 12)

According to the last World Malaria Report [1], there were 584 000 deaths for 198 millions malaria cases worldwide in 2013. Particularly, the disease caused an estimated 437 000 African children died ... [more ▼]

According to the last World Malaria Report [1], there were 584 000 deaths for 198 millions malaria cases worldwide in 2013. Particularly, the disease caused an estimated 437 000 African children died before their fifth birthday, still in 2013. Malaria is caused by a parasite, Plasmodium sp. and transmitted by Anopheles mosquitoes. The problem of parasite resistance towards common available medicines such as chloroquine, mefloquine, quinine, is increasing. In this context, the vegetal kingdom remains the main source of pharmacologically active compounds against this parasitic infection as attested by the famous quinine, isolated from Cinchona sp., artemisinin extracted from Artemisia annua and also atovaquone derived from lapachol found in several Bignoniaceae. All these substances are related to plants with traditional use against fever and malaria. Beside these well-known examples, various new antiplasmodial compounds are frequently discovered from Nature, particularly following an ethnopharmacological approach, as reviewed by several authors in recent years [2-6]. Then, the pharmacological and phytochemical study of plants from traditional pharmacopoeias can be of first interest not only to discover new antimalarial “lead compounds”, but also to valorize local vegetal species whose efficacy and safety would have been demonstrated in laboratory and clinical investigations [7]. As demonstrated in several works from Willcox [8], better knowledge of plants from traditional pharmacopoeias and local valorization of validated traditional remedies in Improved Traditional Medicine (ITM) could allow the access to effective, standardized, available and affordable therapeutics for management of malaria by local populations. After this introductive section, the second part of the talk will be dedicated to the presentation of some results obtained in Liège with Dicoma tomentosa from Burkina-Faso [9], Strychnos icaja from Cameroun [10] and Terminalia mollis from Rwanda [11]. 1. WHO, World Malaria Report 2014, December 2014, Geneva (http://www.who.int/malaria/publications/world_malaria_report_2014/en/). 2. Batista R, Silva Ade J Jr, de Oliveira AB: Plant-derived antimalarial agents: new leads and efficient phytomedicines. Part II. Non-alkaloidal natural products. Molecules 2009, 14:3037-72. 3. Bero J, Frédérich M, Quetin-Leclercq J : Antimalarial compounds isolated from plants used in traditional medicine. Journal of Pharmacy and Pharmacology 2009, 61:1401–1433. 4. Bero J and Quetin-Leclercq J: Natural products published in 2009 from plants traditionally used to treat malaria. Planta Medica 2011, 77:631-40. 5. Kaur K, Jain M, Kaur T, Jain R: Antimalarials from nature. Bioorganic & Medicinal Chemistry 2009, 17:3229–3256. 6. Nogueira CR and Lopes LMX: Antiplasmodial Natural Products. Molecules 2011, 16:2146-2190 7. Ginsburg H and Deharo E: A call for using natural compounds in the development of new antimalarial treatments – an introduction. Malaria Journal 2011, 10 (suppl. 1):S1 8. Willcox M, Graz B, Falquet J, Diakite C, Giani S, Diallo D: A “reverse pharmacology” approach for developing an antimalarial phytomedicine. Malaria journal 2011, 10(suppl1):S8 9. Jansen, O., Tits, M., Angenot, L., Nicolas, J.-P., De Mol, P., Nikiema, J.-B., & Frédérich, M : Anti-plasmodial activity of Dicoma tomentosa (Asteraceae) and identification of urospermal A-15-O-acetate as the main active compound. Malaria Journal 2012, 11, 289. 10. Tchinda, A. T., Jansen, O., Nyemb, J.-N., Tits, M., Dive, G., Angenot, L., & Frédérich, M. Strychnobaillonine, an unsymmetrical bisindole alkaloid with an unprecedented skeleton from Strychnos icaja roots. Journal of Natural Products 2014, 77(4), 1078–82. 11. Muganga, R., Angenot, L., Tits, M., & Frédérich, M : In vitro and in vivo antiplasmodial activity of three Rwandan medicinal plants and identification of their active compounds. Planta Medica 2013, 80(6), 482-489. [less ▲]

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See detailPRESSÃO PARCIAL (PCO2) E FLUXO DE DIÓXIDO DE CARBONO (CO2) EM AMBIENTES DE VÁRZEA AMAZÔNICOS
Amaral, JHF; Barbosa; Kasper, D et al

Conference (2015, July 12)

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See detailA probabilistic multi-scale model for polycrystalline MEMS resonators
Lucas, Vincent ULg; Wu, Ling ULg; Paquay, Stéphane et al

Conference (2015, July 09)

The size of micro-electro-mechanical systems (MEMS) is only one or two orders of magnitude higher than the size of their micro-structure, i.e. their grain size. As a result, the structural properties ... [more ▼]

The size of micro-electro-mechanical systems (MEMS) is only one or two orders of magnitude higher than the size of their micro-structure, i.e. their grain size. As a result, the structural properties exhibit a scatter. As an example we study the beam resonator illustrated in Fig. 1(a), made of poly-silicon material, in which each grain has a random orientation. Solving the problem with a full direct numerical simulation combined to a Monte-Carlo method allows the probability density function to be computed as illustrated in Fig. 1(b). However this methodology is computationally expensive due to the number of degrees of freedom required to study one sample, motivating the development of a non-deterministic 3-scale approach [3]. In a multiscale approach, at each macro-point of the macro-structure, the resolution of a microscale boundary value problem relates the macro-stress tensor to the macro-strain tensor. At the micro-level, the macro-point is viewed as the center of a Representative Volume Element (RVE). The resolution of the micro-scale boundary problem can be performed using finite-element simulations, as in the computational homogenization framework, e.g. [2]. However, to be representative, the micro-volume-element should have a size much bigger than the microstructure size. In the context of the MEMS resonator, this representativity is lost and Statistical Volume Elements (SVE) are considered. These SVEs are generated under the form of a Voronoi tessellation with a random orientation for each silicon grain. Hence, a Monte-Carlo procedure combined with a homogenization technique allows a distribution of the material tensor at the meso-scale to be estimated. The correlation between the meso-scale material tensors of two SVEs separated by a given distance can also be evaluated. A generator at the meso-scale based on the spectral method [4] is implemented. The generator [3] accounts for a lower bound [1] of the meso-scale material tensor in order to ensure the existence of the second-order moment of the Frobenius norm of the generated material tensor inverse [5]. Using the random meso-scale field obtained with the meso-scale generator, which accounts for the spatial correlation, a Monte-Carlo method can be used at the macro-scale to predict the probabilistic behavior of the MEMS resonator. [less ▲]

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See detailSimplified fatigue resistance in mechanical engineering using topology optimization
Collet, Maxime ULg; Bruggi, Matteo; Bauduin, Simon ULg et al

Conference (2015, July 09)

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See detailDeterministic Manufacturing constraints for Optimal Distribution in the Case of Additive Manufacturing
Bauduin, Simon ULg; Collet, Maxime ULg; Duysinx, Pierre ULg et al

Conference (2015, July 09)

An overview of the difficulties of coupling additive manufacturing to topology optimization with various solution founded and implemented.

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See detailAlgorithmic aspects of converting surface mesh data to volumetric images
Plougonven, Erwan ULg; Léonard, Angélique ULg

Conference (2015, July 09)

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data ... [more ▼]

In image analysis, some processes might imply a change or conversion in the structure of the data. The structure types will depend on the processing method and applications, and can consist of pixel data, point sets, finite elements, vector fields, implicit surfaces, graphs, basic shapes (spheres, cylinders, or cubes), etc. The work presented here discusses the problem of converting a triangulated surface mesh to a 3D image, a need that arises for example when using active surface-type segmentation methods of 3D images, shape-fitting, or combining data from laser surface scanning with 3D imaging. During the course of numerous projects, two main classes of mesh-to-image conversions have appeared: those identifying voxels (pixels in a 3D image) that intersect the mesh, or voxels that are contained in the mesh, supposing it defines a closed surface. [less ▲]

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See detailDe "Poétique" à "Points Essais" : (ré)invention du livre ?
Lorent, Fanny ULg

Conference (2015, July 08)

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See detailAttitudes toward Gay and Lesbian Marriage and Parenting Across Seven European Countries
D'Amore, Salvatore ULg; Green, Robert-Jay; Katzuny, Katy et al

Conference (2015, July 08)

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See detailBeyond indiscipline of Labor Market Intermediaries : The Case of Public Employment Services and Private Providers Partnerships
Remy, Céline ULg; Beuker, Laura ULg; Gérard, Julie ULg

Conference (2015, July 08)

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling ... [more ▼]

Following the economic and social changes in the countries of the European Union (liberalization requirements, crisis of the welfare State, diversification of users expectations, etc.), compelling readability needs and modernization of Public Employment Services (PES) have appeared. Meanwhile, a spectacular growth of private employment operators - market and non-market - was recognized by the International Labor Organization in all member states, in order to respond effectively to the increased requests of support and training for the beneficiaries of the PES. In this new context, PES are invited by the European Union (EU) – particularly through its multiple directives – to rethink and reposition their traditional activities of placement, training and support for jobseekers according to a "mixed" management of the labor market. Therefore, PES entrust operation and management of their activities to private providers, as part of a contractual agreement. In this way, these operators provide a "back office function for SPE via a system of delegation governed by a specific division of labor formalized in a partnership agreement between PES and the private provider". Thus, these private labor market intermediaries (LMI’s) as active members on the public orders market work both on their own behalf and on behalf of the public authority. These new collaborations, qualified public-private partnerships (PPPs), allow PES to outsource and delegate a part of their missions they could not achieve internally. So PES combine the role of "actor" and the role of "manager" / "principal" in the labor market. To facilitate the coordination of their activities with the private sector, PES made the decision to create a partnerships service. The officers of this service have the mission to oversee this new form of regulation of the labor market. While collaboration rules are initially determined by the PES, the agents are required to implement them and have the private operators following them. Our interest is to study how these actors – or stakeholder of the PPPs – implement this public action device. Despite differences in both organizational and cultural (for instance bureaucratic rigidity versus informal structure, constraint reporting, management autonomy, etc.), public and private actors work together to serve community and beneficiaries of the PES for their professional integration in the labor market. To analyze how these actors interact and live the partnership relationship, established between agreement and disagreement, we will rely on the economy of conventions and especially on the theoretical contributions of the Theory of justification. In this way, we will identify the different logics of action (present in the merchant, civic, industrial worlds, etc.) that guide the practices of stakeholders, from their discourse and in particular the underlying arguments to justify their actions. Our analysis is rooted in empirical material composed of semi-structured interviews (N=89) and various observations of interactions made within the partnership services and with providers (N=132). These observations focused on three key moments in the life of the partnership: the selection of projects, the monitoring and evaluation of projects by the agents. With this approach, our goal is twofold. On the one hand, we want to highlight the moments when the actors "interpret" the regulatory framework that structure their actions within the partnership relationship. On the other hand, we want to understand the arguments used by actors to justify and legitimize their indiscipline. [less ▲]

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See detailLa presse vidéoludique française : périodisation et enjeux
Dozo, Björn-Olav ULg

Conference (2015, July 08)

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See detailShewhart Control Charts with Guaranteed In-Control Performance
Faraz, Alireza ULg; Heuchenne, Cédric ULg; Woodall, W.H.

Conference (2015, July 08)

The in-control performance of the Shewhart X ̅ and S2 control charts with estimated in-control parameters has been evaluated by a number of authors. Results indicate an unrealistically large amount of ... [more ▼]

The in-control performance of the Shewhart X ̅ and S2 control charts with estimated in-control parameters has been evaluated by a number of authors. Results indicate an unrealistically large amount of Phase I data is needed to have the desired in-control average run length (ARL) value in Phase II. To overcome this problem, it has been recommended that the control limits be adjusted based on a bootstrap method to guarantee that the in-control ARL is at least a specified value with a certain specified probability. In our paper we present simple formulas for the required control limits so that practitioners do not have to use the bootstrap method. An assumption of normality is required. The advantage of our proposed method is in its simplicity; there is no bootstrapping and the control chart constants do not depend on the Phase I sample data. [less ▲]

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See detailCitizen Science and Democratic Citizenship
Van Oudheusden, Michiel ULg; Meyer, Morgan

Conference (2015, July 08)

Citizen science (CS) is now widely recognized as a scienti c research practice that engages "nonscientists," such as journalists, artists, hackers, and entrepreneurs. Examples of CS include amateur ... [more ▼]

Citizen science (CS) is now widely recognized as a scienti c research practice that engages "nonscientists," such as journalists, artists, hackers, and entrepreneurs. Examples of CS include amateur astronomy, biohacking, video gaming, and ornithology, among many others. As many of these practices serve public purposes (e.g. educational goals) and emanate within participatory cultures (e.g. the open science movement), CS can be inscribed in a politics of openness, transparency, and inclusion. These politics are potentially reinforced by the policy uptake of CS (e.g. EU White Paper on CS). Yet, despite its growing public significance and potential to render science more inclusive, CS embeds divergent, often conicting, assumptions about the means and ends of science and the role of the citizen/scientist in contemporary democracy. For instance, in its 'purest' form, CS emerges as a reaction against industry and institutional science, in so far as these institutes are seen to inhibit open knowledge sharing. On the other hand, CS sometimes links to commercial endeavors. CS should thus be approached as a multilayered practice that has the power to reshape existing policies, categories, and identities. Taking these reflections into consideration, this panel asks how CS (re)constructs the contemporary citizen, scientist, and citizen scientist. How are citizens transformed into active 'co-creators' of science? Which political rights do citizen scientists claim, as individuals or as groups? Which tools do citizen scientists mobilize to build communities around scientific endeavor? How local or global are the politics of CS? How do policymakers act as facilitators, patrons, or challengers of a more collective, open science? These questions demand critical attention, as CS is performative of democratic citizenship. The panel's questions resonate with the following conference themes: How are publics constructed by policies? To what extent are groups and identities shaped in the policymaking process? How do publics express themselves? [less ▲]

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See detailAttitudes toward Gay and Lesbian Marriage and Parenting in Italy
Baiocco, Roberto; D'Amore, Salvatore ULg; Green, Robert-Jay et al

Conference (2015, July 08)

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See detailTreatments for patients with disorders of consciousness
Thibaut, Aurore ULg

Conference (2015, July 07)

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See detailStress constrained topology optimization for additive manufacturing: Specific character and solution aspects
Duysinx, Pierre ULg

Conference (2015, July 07)

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress ... [more ▼]

Since the fundamental work by Bendsøe and Kikuchi (1988), topology optimization has been based on compliance type formulations (Bendsoe & Sigmund, 2003) while the number of works considering stress constraints are rather limited (Duysinx & Bendsoe, 1998). More recently the generalized shape optimization approach using level set methods (see for instance Allaire, Jouve, Troader, 2004, Belytchko, Xiao, Parimi, 2003) has followed the tracks of topology optimization and has mainly been focusing on compliance minimization problems. The ‘compliance type’ formulation has produced quite interesting results in many problems because controlling the energy and the displacements under the loads is generally favourable for deflection control and because, for one load case, the compliance minimization leads to a fully stressed design nearly everywhere in the structure. However there are theoretical results that clearly show that the strongest and the stiffest structural layout can be quite different. As demonstrated in Rozvany & Birker (1994) truss topology optimization can lead to different results when there are several load cases, different stress limits in tension and compression, or when there are several materials involved. Therefore, the first goal of the paper points out the importance of considering stress constraints as soon as the preliminary design phase, that is, to include stress constraints in the topology optimization problem. Revisiting some contributions of the authors, this paper aims at illustrating the key role of stress constraints in the framework of topology optimization of continuum structures. The recent developments are able to treat: • Integrated stress criteria (i.e. global) relaxed stress constraints that aggregate the stress constraints in each finite element in order to be able to circumvent the large scale character of the local stress constraints. • Stress criteria that are able to tackle non equal stress limits in tension and compression. The usual von Mises criterion is unable to predict real-life designs when the structure is made of materials with unequal stress limits like concrete or composite materials. These different behaviours in tension and compression result in quite specific designs. Numerical applications make possible to point out the different nature of structural lay out for maximum strength and maximum stiffness. This one is clearly demonstrated in two kinds of particular situations: once several load cases are considered and when unequal stress limits in tension and compression are involved. The second contribution of the paper deals with the solution aspects of large scale constrained optimization problems. Because of the huge number of design variables, dual methods combined with local convex approximations such as CONLIN (Fleury, 1989) or MMA (Svanberg, 1987) are well indicated to solve classical topology optimization methods. However stress constrained problems introduce also a so large number of active constraints that one comes to a rather delicate situation. We show that the optimizer effort increases mostly as the cube of the number of constraints. In order to circumvent the problem, the idea developed in the paper is to combine first or second order approximations (Bruyneel, Duysinx, Fleury, 2002) with zero order approximations of stress constraints, especially for the subset of restrictions that are likely not to be active or not to change too fast. At first the paper presents the way to derive zero-order approximations of -relaxed stress constraints (that is necessary to cope with the singularity phenomenon of stress constraints in topology optimization). Then the proposed hybrid approach mixing approximation of different orders is benchmarked on numerical applications illustrating the reduction of computation time for solving optimization problems without sacrifying to the robustness and efficiency. Numerical applications will investigate topology optimized benchmark examples combined with additive manufacturing fabrication to illustrate the developments. [less ▲]

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See detailCO2-sourced non-isocyanate polyurethanes: from the monomer synthesis to the elaboration of polymeric materials
Gennen, Sandro ULg; Grignard, Bruno ULg; Gilbert, Bernard ULg et al

Conference (2015, July 07)

Due to problems related to the rarefaction of fossil resources and the global warming that comes from CO2 emissions, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and ... [more ▼]

Due to problems related to the rarefaction of fossil resources and the global warming that comes from CO2 emissions, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and environmentally friendly must be explored to produce chemicals. Besides the valorization of bio-based raw materials, the use of CO2 as a C1 carbon source into added-value products has gained interest in both academic and industrial fields. One promising way to valorize CO2 relies on its chemical fixation onto epoxides to produce cyclic carbonates that find applications as electrolytes in lithium ion batteries, as aprotic polar solvents or as useful intermediates for polycarbonates. Cyclic carbonates also react with primary amines to produce 2-hydroxyethylurethane. This reaction can be extrapolated to the synthesis of non-isocyanate polyurethanes (NIPU) by polyaddition of bifunctional cyclic carbonates with diamines.5 This study focusses on (i) the synthesis of cyclic carbonates using new highly efficient organocatalysts and (ii) their valorization as monomers to produce non-isocyanate polyurethanes. First, we have identified a bicomponent organocatalyst for the very fast synthesis of cyclic carbonates from CO2 and epoxides under very mild reaction conditions. Kinetics of reactions were followed by online Raman spectroscopy. NMR titrations were realized to evidence the mechanism of activation of this novel organocatalytic system that will be discussed in detail this talk. The second objective relies on the development of new efficient organocatalysts for the synthesis of high molar masses NIPUs in short reaction times. Organic compounds interacting with the cyclic carbonate by hydrogen bonding were identified and their catalytic activity was highlighted by a model reaction between ethylene carbonate and a primary amine before extrapolation to the synthesis of NIPUs that find applications as coatings or foamed materials. [less ▲]

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See detailEfficient hydrogen-bond donor activators for the synthesis of bio-based cyclic carbonates from CO2 and vegetable oils: a combined in-situ FT-IR and DFT study
Alves, Margot ULg; Méreau, Raphaël; Grignard, Bruno ULg et al

Conference (2015, July 06)

The present research aims at developing new very efficient organocatalysts for the chemical fixation of carbon dioxide onto epoxides that are precursors of non-isocyanate polyurethanes (NIPUs). Although ... [more ▼]

The present research aims at developing new very efficient organocatalysts for the chemical fixation of carbon dioxide onto epoxides that are precursors of non-isocyanate polyurethanes (NIPUs). Although this area of research is the subject of many works, the catalytic performance must be further enhanced in particular for the carbonatation of vegetable-based precursors while respecting environmental standards. In this context, we developed a new organocatalytic platform based on the combination of ammonium salts with single or double hydrogen bond donor activators that showed unexpected catalytic activity for the fast addition of CO2 onto epoxidized oils under mild conditions. First of all, in situ kinetic studies of the cycloaddition of CO2 onto model epoxidized oils were monitored by FT-IR spectroscopy in order to evaluate the influence of the hydrogen bond structure and various parameters such as the pressure, the temperature, the catalyst loading, and the nature of the epoxide on the reaction kinetics. Thanks to this catalyst screening, we found that ammonium salt/fluorinated hydrogen bond donors bicomponent organocatalysts were by far more efficient than that proposed in the literature under mild conditions (60°C, 2MPa). Then, the reaction mechanism of the organocatalyzed cycloaddition of propylene oxide onto CO2 was elucidated by performing Density Functional Theory (DFT). Our theoretical results highlighted the key role of the hydrogen bond interaction between the epoxide and the activators for the enhancement of the catalytic platform’s efficiency. [less ▲]

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See detailA Non-Local Damage-Enhanced Incremental-Secant Mean-Field-Homogenization For Composite Laminate Failure Predictions
Wu, Ling ULg; Adam, Laurent; Doghri, Issam et al

Conference (2015, July 06)

Recently, the authors have presented an incremental-secant mean-field homogenisation (MFH) process for non-linear composite materials [4]. In this formulation, a virtual elastic unloading is applied to ... [more ▼]

Recently, the authors have presented an incremental-secant mean-field homogenisation (MFH) process for non-linear composite materials [4]. In this formulation, a virtual elastic unloading is applied to evaluate the virtual residual stress and strain states reached in each elasto-plastic phase. These virtual states are then used as a starting point to apply a secant homogenization method. This incremental-secant MFH process can handle non-proportional and nonmonotonic loadings, and naturally possesses an isotropic instantaneous stiffness operator to be used in the Eshelby tensor. This incremental-secant MFH homogenization can account for the first and second statistical moment estimation of the current yield stress in the composite phases during the computation of the plastic flow. When accounting for a second statistical moment estimation, the plastic yield in the composite material phases is captured with a higher accuracy, improving the predictions, mainly in the case of short fiber composite materials [6], see Fig. 1(a). The incremental MFH can handle material softening when extended to include a damage model. Indeed, as the secant formulation is applied from an unloaded state, the inclusion phase can be elastically unloaded during the softening of the matrix phase, contrarily to the case of the incremental-tangent method [3, 5], see Fig. 1(b). Moreover, when formulating the damage model in the composite phases in a non-local way, as with the non-local implicit approach, [1, 2], the MFH scheme can be used to model strain localization in composite structures [5], without suffering from the loss of the solution uniqueness. [less ▲]

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See detailPhytoplankton abundance and diversity in the Congo river at high and low waters
Stoyneva, MP; Descy, JP; Bouillon, S et al

Conference (2015, July 05)

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See detailGerard du Frattre, oeuvre de transition entre les périodes médiévale et renaissante
Lambert, Adelaïde ULg

Conference (2015, July 04)

Gérard du Frattre est une compilation épique contenue dans le manuscrit inédit Paris, BnF, fr. 12791, copié à Paris en 1525 par Jacques Le Gros. Cette œuvre rassemble trois réfections en prose de chansons ... [more ▼]

Gérard du Frattre est une compilation épique contenue dans le manuscrit inédit Paris, BnF, fr. 12791, copié à Paris en 1525 par Jacques Le Gros. Cette œuvre rassemble trois réfections en prose de chansons de geste du XIIe siècle : Fierabras, la Chanson d’Aspremont et le Pèlerinage de Charlemagne. Bien que n’ayant jamais été imprimé, ce vaste ensemble est à l’origine de Gérard d’Euphrate de Jean Maugin, sorti des presses des éditeurs des Amadis en 1549, qui construit à rebours les enfances du héros Gérard et se présente comme le premier tome d’une série de six livres. Si les cinq volumes suivants n’ont jamais vu le jour, le contenu du manuscrit correspond à la suite de la narration de l’imprimé, ce qui pourrait suggérer un vaste projet éditorial avorté (Cooper, 2014). Dans un premier temps, cette intervention avait pour objectif de souligner l’apport de Gérard du Frattre à la question du découpage de la temporalité, ainsi que d’éprouver les premières pistes méthodologiques que ce texte hybride permet d’envisager et que nous souhaiterions aborder dans notre projet de thèse, qui consiste en l’édition et l’étude de l’œuvre. Ainsi, parallèlement à la pérennité de matières médiévales, la variation formelle — le passage à la prose puis à l’imprimé — reconfigure progressivement la structure et l’écriture du genre épique. Dans un second temps, c’est sur la question de la rupture engendrée par l’apparition de l’imprimerie que s’est centré notre exposé. La majorité des textes épiques popularisés par ce nouveau média est issue d’un corpus de mises en prose, dont le ms. Paris, BnF, fr. 12791 est l’un des derniers nés. La collation du chapitre initial de Gérard du Frattre avec celui de Gérard d’Euphrate nous a permis d’épingler quelques cas de rajeunissements stylistiques, et surtout de souligner la dépendance de l’imprimé au manuscrit et à la tradition épique antérieure, cela malgré la présentation typographique et iconographique adoptée par Gérard d’Euphrate, qui l’éloigne de la veine des « vieux romans » pour l’assimiler à celle des Amadis. Cet écart par rapport au « parcours classique » des épopées tardives suggère en outre un nouvel horizon d’attente et illustre de façon exemplaire la nature protéiforme du genre épique. [less ▲]

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See detailLa paix de Westphalie (1648) : une rupture dans l’histoire diplomatique du Saint-Siège ? Confessionnalisation et médiation pontificale en question.
Regibeau, Julien ULg

Conference (2015, July 04)

La signature des traités de Westphalie, en 1648, a longtemps été considérée comme une rupture nette dans l’histoire politico-religieuse. Elle aurait conduit à l’effondrement de la christianitas médiévale ... [more ▼]

La signature des traités de Westphalie, en 1648, a longtemps été considérée comme une rupture nette dans l’histoire politico-religieuse. Elle aurait conduit à l’effondrement de la christianitas médiévale et à la naissance de l’Europe des États modernes . Ce changement de paradigme supposerait l’échec à long terme de la politique du Saint-Siège. L’historiographie récente permet cependant de revoir cette double interprétation, montrant notamment que le rôle diplomatique joué par Rome lors des négociations en Westphalie est plus complexe. Le but de ma communication est de réévaluer la théorie qui voudrait que la paix de Westphalie soit une rupture pour l’histoire des relations internationales et, par voie de conséquence, pour la diplomatie pontificale. Premièrement, je mets en avant les critères qui poussent régulièrement les historiens à envisager cette paix comme une défaite de Rome. Cette première partie m’entraine ensuite à définir rapidement le concept de confessionnalisation des relations internationales et à montrer qu’il est aujourd’hui réinterrogé par la recherche. Ce concept fait de la lutte confessionnelle le principal facteur structurant les relations internationales entre 1550 et 1650. Or il semble aujourd’hui peu à même d’expliquer toute la diversité des discours et des pratiques qui apparaissent alors dans les correspondances diplomatiques, y compris celles des ambassadeurs du Saint-Siège. Dans un troisième temps, je me concentre plus spécifiquement sur la figure du pape comme padre comune des princes catholiques et donc médiateur de leurs conflits. Ce rôle mérite d’être appréhendé dans le détail de chaque négociation. L’étude de la médiation des nonces ordinaires à l’époque des congrès en Westphalie permettrait ainsi de proposer une nouvelle lecture du rôle joué par la papauté à l’occasion de cette paix. Cela permettrait également d’adjoindre, à la temporalité de la confessionnalisation, d’autres temporalités parallèles. [less ▲]

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See detail« Folded time » : le temps en héritage dans l’œuvre de Gail Jones
Belleflamme, Valérie-Anne ULg

Conference (2015, July 04)

« Folded time » : le temps en héritage dans l’œuvre de Gail Jones The photograph of someone one loves, as a child: folded time. The present is given adorable density; in the face of the beloved rests an ... [more ▼]

« Folded time » : le temps en héritage dans l’œuvre de Gail Jones The photograph of someone one loves, as a child: folded time. The present is given adorable density; in the face of the beloved rests an earlier face. (Gail Jones, Dreams of Speaking, p. 37) Le temps pour Gail Jones n’est ni chronologique, ni linéaire, ni cyclique : telles des couches mémorielles se superposant les unes par rapport aux autres sans pour autant s’additionner, le temps, selon Jones, est « folded » (plissé, replié) et le moment présent n’est que le résultat d’un long processus de soustractions. Romancière, nouvelliste et essayiste australienne, Gail Jones est aussi une contemporaine de la fameuse « réconciliation australienne ». Du fait de son identité « blanche » et ses origines « européennes », Jones s’inscrit ainsi dans une lignée d’écrivains confrontés aux dangers liés à la victimisation symptomatique des cultures colonisatrices à l’époque postcoloniale. Afin d’aborder la question de la légitimité de l’héritage culturel, linguistique, littéraire et historique dans les récits traumatiques, sans pour autant assimiler le rôle réparateur des témoignages des victimes au rôle rédempteur des récits traumatiques des exterminateurs, Jones joue avec la notion de temporalité. C’est en effet au travers de son œuvre romanesque que Jones montre comment l’émergence d’événements du passé met en lumière un pan de l’histoire de l’Australie qui, jusqu’ici, fut passé sous silence. De même, dans une interview, Jones a exprimé son envie d’écrire sur l’amnésie historique, sur ce que c’est que d’oublier, d’avoir une histoire lacunaire (voir Block 2). Son but, je pense, n’est pas tant de combler le vide au centre de l’Histoire de l’Australie que d’écrire sur ce phénomène typiquement (post)colonial. Mon exposé s’attachera donc à montrer par quels moyens techniques et littéraires Jones tente de faire résonner les dangers récurrents liés à l’écriture et à la transmission orale de l’indicible dans la littérature contemporaine de l’Australie colonisatrice. Jones, je soutiens, fait preuve de grande subtilité à l’égard des sujets souvent très délicats que sont l’indigénéité, la marginalité, le racisme, le trauma, la victimisation et la violence, pour n’en citer que quelques uns, en ayant recours à des techniques d’écriture originales et contre-discursives, dont l’allégorie et l’intertextualité. Par ailleurs, son approche de la temporalité, tant au niveau de la forme (fragments, flashbacks, points de vue) que du contenu (troubles de la mémoire, héritage) et sa conception soustractive de l’histoire contribuent au caractère unique de sa vision du monde et de son écriture. [less ▲]

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See detailLimites temporelles et conceptualisation de l'écrivain
Daubercies, Laurence ULg

Conference (2015, July 04)

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See detailThe choice of the cooperative legal form: Any rationality?
Dufays, Frédéric ULg; O'Shea, Noreen

Conference (2015, July 04)

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See detailSynécismes et transformations du paysage religieux en Grèce antique
Palamidis, Alaya ULg

Conference (2015, July 03)

Detailed reference viewed: 28 (5 ULg)