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See detailPsychopathy and emotions: would emotional distancing make more efficient in cognitive tasks?
Grandjean, Sylvie; Dehon, Hedwige ULg; Blavier, Adelaïde ULg et al

Poster (2015, May 28)

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See detailBorderline Personality Disorder through the Rorschach test
Rommes, Jennifer; Englebert, Jérôme ULg; Blavier, Adelaïde ULg

Poster (2015, May 28)

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See detailQuelle place accorder aux écritures de la réception dans le contexte de la formation initiale? Du comportement des futurs enseignants face à des médiations de la lecture à l'élaboration de dispositifs de formation
De Croix, Séverine ULg; Ledur, Dominique

Conference (2015, May 28)

L’exploitation des écritures de la réception en formation initiale des enseignants fait aujourd’hui l’objet d’un large consensus (Joole, 2013 ; Chabanne & Dufays, 2011; Mazauric, Fourtanier & Langlade ... [more ▼]

L’exploitation des écritures de la réception en formation initiale des enseignants fait aujourd’hui l’objet d’un large consensus (Joole, 2013 ; Chabanne & Dufays, 2011; Mazauric, Fourtanier & Langlade, 2011 ; Vanhulle & Schillings, 2004). Nous souhaitons nous interroger sur les moyens, les objectifs et les effets attendus de cette exploitation (axe 4 de l’appel à communications). Le présent projet porte, dans un premier temps, sur l’observation des réactions d’une centaine de futurs enseignants de français du secondaire, tous niveaux confondus, face à un corpus de médiations écrites de la lecture, produites par des élèves de 12 à 18 ans, lecteurs experts et en difficulté. Ces écrits relèvent de genres diversifiés (journaux de lecture, notes critiques, traces collectées à l’occasion d’un dévoilement progressif, réponses à des questions, etc.) et de statuts différents (écrits de travail ou productions finales susceptibles d’être évaluées). Les consignes d’analyse devaient conduire les étudiants à repérer les éventuelles difficultés des lecteurs (ou leurs réussites), à reconstruire les tâches, à relever différents positionnements face aux textes, etc. Nos constats mettent notamment en évidence une tendance à investir ces écrits de façon normative (prédominance des difficultés du lecteur, notamment linguistiques, au détriment d’une prise en compte des difficultés générées par les textes et/ou les tâches scolaires) et une faible conscience de la complexité de l’activité de compréhension/interprétation. L’analyse des données collectées à l’occasion de ce travail incite, dans un deuxième temps, à privilégier quatre directions pour apprendre aux futurs maitres de lecture à lire des écrits de la réception et pour les amener par ce biais à développer des compétences et gestes professionnels en didactique de la lecture littéraire : modéliser l’activité de compréhension/interprétation, identifier les éventuelles difficultés de lecture, sélectionner des textes pour la classe et les associer à des médiations adaptées, percevoir les caractéristiques et les visées des tâches (y compris anticiper les éventuels malentendus générés par celles-ci et organiser leur progression). Ces axes d’intervention seront illustrés par quelques exemples de dispositifs de formation. [less ▲]

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See detailMaternal representations, social context and substance abuse
Halin, Stéphanie ULg; Combe, Samantha; Glowacz, Fabienne ULg et al

Poster (2015, May 28)

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See detailWork incapacity and chronic pain patients: Is there an impact of work incapacity on anxiety and depression?
Beaumel, Alexia; Vanootighem, Valentine ULg; Gillet, Aline ULg et al

Poster (2015, May 28)

In 2011, a report of the Federal Public Service have shown that 8.5% of the Belgian population suffers from chronic pains, which represents 938 300 belgian people (Berquin et al., 2011). These persistent ... [more ▼]

In 2011, a report of the Federal Public Service have shown that 8.5% of the Belgian population suffers from chronic pains, which represents 938 300 belgian people (Berquin et al., 2011). These persistent pains may result in functional limitations on both domestic and professional domains which may lead to temporary or permanently work incapacity (Faymonville et al., 2014). These incapacities may in turn cause a social withdrawal and a tendency to focus on pain (Berquin et al., 2011). Additionally, patients are prone to emotional modifications due to persistent pain (Ossipov et al., 2010). All of these factors may contribute in the emergence of anxiety and depressive symptoms. The present study examines the impact of type of work incapacities (at work, temporary incapacity and permanent incapacity) on anxiety and depression scores as a function of diagnoses (fibromyalgia, chronic pain syndrome, back pain, polyalgia). 123 patients suffering from chronic pain completed a measure of anxiety and depression (HADS), and a self-reported questionnaire of psychological and physical disability at work. We did not found any significant effect of type of work incapacities on anxiety and depression scores. Results present tables of frequencies to illustrate the social and professional situations of patients as a function of chronic pain diagnoses. [less ▲]

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See detailParental and romantic attachments in teen datings : different meanings in boys' and girls' intimacy
Courtain, Audrey ULg; Lepas, Jennifer; Boulard, Aurore ULg et al

Poster (2015, May 28)

First proposing a relational understanding of the child’s very first years, attachment theory has since then been taken into consideration in friendships and romantic relationships. Indeed, the internal ... [more ▼]

First proposing a relational understanding of the child’s very first years, attachment theory has since then been taken into consideration in friendships and romantic relationships. Indeed, the internal working models (IWM) built upon early interactions are to be used on and on in many other situations as guidelines to understand what is going on for the self, this particular other and their specific relationship. Different attachment styles are thus likely to develop: secure or insecure (anxious/preoccupied, avoidant/dismissive, fearful). Considering teen dating, attachment is deeply involved, especially for two reasons: first, a certain questioning, but also re-actualization, of the attachment to parents; second, a new kind of attachment, meaning the one to the romantic partner. These elements lead us to test hypotheses linking attachment to parents and attachment to romantic partners, but also linking these attachments to some teen dating characteristics, such as the age when first dating, the number of love relationships, the longest-lasting love relationship and the fear of intimacy. Our hypothesis was tested among 283 teenagers (mean age = 17.43) with two self-administered questionnaires (the Behavioral Systems Questionnaire and the Fear of Intimacy Scale). Our statistical analyses were made of Pearson Chi², Anova and Post-Hoc Fisher (LSD). We see three types of interesting results. First, there is a significant relationship between attachment (parental and romantic attachments) and the number of love relationships and the fear of intimacy. Second, these relationships are differently established once considered the attachment modalities. Third, gender differences appear, girls looking more influenced by their attachment style than boys. [less ▲]

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See detailHeterogeneity of multitasking abilities in schizophrenia.
Laloyaux, Julien ULg; Van der Linden, Martial ULg; Laroi, Frank ULg

Conference (2015, May 28)

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to ... [more ▼]

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to activities (e.g. preparing a meal) where the person has to: (a) carry out and alternate between different tasks that vary in terms of priority, difficulty and duration; (b) define the tasks’ targets; (c) and face unexpected problems during the realization of these tasks. Moreover, schizophrenia is characterized by a great heterogeneity in regard to their everyday life difficulties and cognitive functioning. At present, patients’ multitasking capacities have not been adequately examined in the literature due to an absence of suitable assessment strategies. We thus recently developed a computerized real-life activity task designed to take into account the complex and multitasking nature of certain everyday life activities where participants are required to prepare a room for a meeting (i.e. the Computerized Meeting Preparation Task, CMPT). The aim of this study was to examine the multitasking abilities in persons diagnosed with schizophrenia and in particular the existence of subgroups of patients in regard to their performances on cognitive measures and on the CMPT. Sixty-two patients diagnosed with schizophrenia and 39 paired healthy controls completed the CMPT and a cognitive battery. The results reveal that the CMPT possesses good sensitivity and suggest three underlying constructs of multitasking (Memory, Planning and Intent), which were found to be underpinned by several cognitive functions and multitasking aspects. Moreover, cluster analyses revealed subgroups of patients differing in terms of their cognitive and CMPT performances. Taken together, these results show the need for a cognitive model of multitasking abilities in persons diagnosed with schiozphrenia. Taken together, this cognitive model and the CMPT, could be a good basis for cognitive interventions of multitasking abilities in schizophrenia. Finally, the results underline the heterogeneity of schizophrenia. [less ▲]

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See detailTool use and hafting in the Middle Palaeolithic of Northern Africa An on-going use-wear analysis on the Mousterian/Aterian assemblages of Ifri n’Ammar (Morocco)
Tomasso, Sonja ULg; Rots, Veerle ULg

Conference (2015, May 28)

The so-called “Aterian Culture” has received attention since the early days of prehistoric archaeology in Northern Africa. Several definitions were proposed, which triggered a debate around this cultural ... [more ▼]

The so-called “Aterian Culture” has received attention since the early days of prehistoric archaeology in Northern Africa. Several definitions were proposed, which triggered a debate around this cultural concept. In particular the presence of the tanged tools was a crucial element in these debates and the tangs were considered to potentially represent the earliest indications of hafting, or at least of intentional morphological adaptations in view of hafting. In contrast to numerous typological and technological studies of Aterian and Mousterian assemblages, use-wear analyses have been scarce up until today. However, for a better understanding of several aspects of these Middle Palaeolithic “cultures”, functional data needs to be taken into consideration. Given the issue of tanged pieces, the potential of such detailed studies on production, hafting and use is high. In this paper, the first results will be presented of an on-going use-wear analysis on tools from the Aterian/Mousterian assemblages of Ifri n’Ammar. This rock shelter presents an ideal case thanks to its particularly rich and well preserved stratigraphy. Around 200 artefacts have been selected up to now, based on their degree of preservation and without restrictions on the level of the tool types. Artefacts were examined macroscopically and microscopically in a search for evidence of their production, hafting and use and an experimental program was set up. Archaeological interpretations are based on new experiments, as well as on the existing large experimental reference collection available at TraceoLab at the University of Liège. The long-term goal of the study is to use a functional approach to answer questions related to lithic assemblage variability. At Ifri n’Ammar, it is clear that the tangs occur on a variety of tools. Due to the presence of tangs in the Aterian and their absence in the Mousterian, it can be hypothesized that there was a shift in hafting techniques between the two cultures/periods. In order to understand whether this change was triggered by functional, cultural, or environmental factors, more functional data is clearly needed. [less ▲]

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See detailRomantic relationship and delinquency : which desistance factor ?
Puglia, Rosa ULg; Lepas, Jennifer; Glowacz, Fabienne ULg

Poster (2015, May 28)

A large number of studies (Stouthamer-Loeber, Loeber, Wei, Farrington & Wikstrom, 2002) have shown that the quality of parent-child relationship influences delinquency behavior during adolescence. So, the ... [more ▼]

A large number of studies (Stouthamer-Loeber, Loeber, Wei, Farrington & Wikstrom, 2002) have shown that the quality of parent-child relationship influences delinquency behavior during adolescence. So, the poorer the quality of relationship between a parent and his child is, the higher the probability that the child adopts delinquent behavior. However, recent studies (Giordano et al., 2002 ; Laub et al., 1998 ; Meeus & al., 2004 ; Woordward et al., 2002) have questioned the persistence of this association when people involved in a romantic relationship. These research have shown that quality of parent-child relationship predict delinquency in adolescents and young adults who do not have an intimate partner. But in adolescents and young adults who have an intimate partner, quality of parent-child relationship becomes obsolete. To be involved in an intimate relationship leads to less delinquency. Furthermore, results are concordant with research about desistance from delinquency that have shown that marriage leads to less criminality (Forrest & Hay, 2011 ; Sampson & Laub, 1993). These studies (Meus & al., 2004 ; Sampson & Laub, 1993) specify that it is quality of relationship rather than simply being in a romantic relationship that have an impact on desistance from delinquency. From empirical research conducted with adolescents and young adults (N=283) aged from 16 to 22 years old, and from a clinical research, we have explored links between parental attachment, romantic attachment and delinquency. We wondered if romantic attachment promotes desistance from delinquency whatever parental attachment. Behavioral System Questionnaire (Wehner & Furman, 1999) and self-reported delinquency scale (Born & Gavray, 1994) have used in this context. It appears that most of the participants have been involved in a significant romantic relationship. This romantic relationship is mainly characterized by a secure attachment. So, it leads to less deviant behaviors. On the other hand, parental attachment does not lead to less deviant behaviors. It also appears that attachment style that one develops towards one’s parent is not unchangeable. Romantic relationship during adolescence and adulthood can bring emotional and relational modifications. [less ▲]

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See detailThe impact of ageing on episodic memory encoding: an fMRI study
François, Sarah ULg; Angel, Lucie; Salmon, Eric ULg et al

Poster (2015, May 28)

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear ... [more ▼]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear to recruit prefrontal areas bilaterally when their encoding is successful, while in young adults this activation is found to be left-lateralized (b). In this study, we were interested in the differences between younger and older participant regarding cerebral activity during encoding depending on whether the item elicited recollection or familiarity during the recognition phase. Twenty young volunteers (aged 19 to 29 years old) and 19 older volunteers (aged 60 to 78 years old) were presented visual stimuli depicting objects. During a first fMRI session, they were asked to make a size judgement about them. Then, in a second phase, the subjects were shown the items previously encountered during the encoding phase, as well as distractors. Participants' task was to determine which one were new and which one were seen earlier. For the latter, they also performed a Remember-Know judgement. Data were analysed using SPM8, with an event design comparing modifications in cerebral activity between the two subjects groups during encoding (1) for the items leading to recollection during the recognition phase compared to those leading to familiarity, and (2) for the items associated with familiarity during the recognition phase compared to those which were not recognized. Results show that older adults display a heightened activity in the right middle frontal gyrus, medial cingulate and paracingulate left gyri as well as in the precuneus, bilaterally when they engage recollection processes. Given that activations in these areas did not correlate with performance, they could be interepreted either as dedifferentiation or as an attempt of the ageing brain to compensate for a less elaborate encoding. However, no increase of activity was associated with familiarity processes in older adults, possibly because they are less demanding regarding attentional resources. (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Duverne, S., Motamedinia, S., & Rugg, M. D. (2009). The relationship between aging, performance, and the neural correlates of successful memory encoding. Cerebral Cortex, 19(3), 733-744. doi:10.1093/cercor/bhn122 [less ▲]

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See detailThe effect of ageing and encoding instructions on episodic memory
Hagelstein, Catherine ULg; François, Sarah ULg; Manard, Marine ULg et al

Poster (2015, May 28)

During ageing, a decline in episodic memory is observed, characterized by decreased recollection (a). In this study, we investigated the influence of encoding instructions, intentional or incidental, on ... [more ▼]

During ageing, a decline in episodic memory is observed, characterized by decreased recollection (a). In this study, we investigated the influence of encoding instructions, intentional or incidental, on the performance of younger and older adults during an episodic memory task. Twenty young volunteers (aged 18 to 30 years old) and 20 older volunteers (aged 61 to 72 years old) participated in this experiment. The stimuli consisted of 300 black-and-white drawings of common objects. The task comprised two steps. During the encoding phase, 100 items were presented once ("hard" condition) and 100 other items were presented twice ("easy" condition). During recognition, the items from the encoding phase were presented again, as well as 100 new items. In each age group, half of the participants received incidental encoding instructions (they had to make size judgements about the objects depicted) while the other half were explicitly asked to memorize the objects presented because they would be asked to recognize them later on (intentional encoding). During recognition, they performed a Remember-Know judgement for the items they believed they had seen earlier. We carried out ANOVAs in order to test for the influence of instructions, age group and number of repetitions of the items in one hand on the percentage of recollection and on the other hand on the percentage of familiarity (p<.05). Results show a significant effect of age, with more correct recollection responses in young adults, whereas more correct familiarity was found in older adults. Furthermore, it was found that the items presented twice lead to more recollection than those presented only once. Finally, these results also suggest that in the older group of participants, only for the items presented twice, intentional encoding instructions lead to more recollection and less familiarity. This finding is consistent with previous work showing that the elderly do not easily use elaborate encoding strategies, and that they need more support (here, a second exposition to the material) in order to perform a deep encoding when they are encouraged to do so with intentional learning instructions (b). (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Froger, C., Bouazzaoui, B., Isingrini, M., & Taconnat, L. (2012). Study time allocation deficit of older adults: the role of environmental support at encoding? Psychology and Aging, 27(3), 577-588. doi:10.1037/a0026358 [less ▲]

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See detailStone tool hafting and use in the European Upper Palaeolithic: the first results of the analysis of Gravettian tools from Hohle Fels
Taipale, Noora ULg; Rots, Veerle ULg

Conference (2015, May 28)

European Upper Palaeolithic lithic assemblages have been so far defined largely on a typological or technological basis, while extensive studies that would utilise the full potential of microwear analysis ... [more ▼]

European Upper Palaeolithic lithic assemblages have been so far defined largely on a typological or technological basis, while extensive studies that would utilise the full potential of microwear analysis have been few. This contribution presents the first results of an ongoing PhD project dedicated to the variability in stone tool use and hafting in the Upper Palaeolithic of Central and Western Europe. The aim of the project is to understand the development as well as regional patterns in tool hafting and use in the Gravettian and Magdalenian, and thus better explain the observed morphological and technological shifts. For this purpose, samples of tools from five European key sites with well-dated sequences (Hohle Fels, Geißenklösterle, Vogelherd, Maisières-Canal, and Abri Pataud) will be analysed giving a special emphasis on hafting traces. The study wishes to promote functional analysis as an integral part of technological studies, not as a mere side note. The German cave site Hohle Fels is used here as a case study to illustrate the potential of this kind of approach. The first results of the analysis of the site’s Gravettian material will be put into a wider context of earlier published results as well as preliminary observations made on the other assemblages included in the present study. Building on these results, the impact of tool hafting and use on the morphology of Gravettian lithic implements will be discussed. [less ▲]

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See detailThe neural bases of proactive and reactive control processes in healthy aging
Manard, Marine ULg; François, Sarah ULg; SALMON, Eric ULg et al

Poster (2015, May 28)

Background. Research on cognitive control suggests an age-related decline in proactive control abilities (an anticipatory form of control) whereas reactive control (consecutive to conflict detection ... [more ▼]

Background. Research on cognitive control suggests an age-related decline in proactive control abilities (an anticipatory form of control) whereas reactive control (consecutive to conflict detection) seems to remain intact [1]. As proactive and reactive control abilities were associated to specific brain networks [2], this study investigated age-related effects on the neural substrates associated to each kind of control. Method. A modified form of the Stroop task was administered to 16 young and 16 older adults in an event-related fMRI experiment. In this version of the Stroop task, three different contexts were created: (1) a mostly congruent context (MC, inducing reactive control) with a majority of congruent items, (2) a mostly incongruent context (MI, inducing proactive control) with mainly interfering items, (3) a neutral context (MN) with mainly neutral items. Preprocessing and statistical analyses were performed with SPM8 (p<.001 uncorrected). Results. Behavioral results (p<0.05) indicated faster processing of interferent items in the MI than MC context in young participants only. With regard to neuroimaging data, the comparison of the two groups showed that the processing of interferent items in the MI context is associated to decreased activity in (mainly right-sided) frontal and temporal areas in the older group. On the contrary, in the MC context, increased activity was observed in bilateral frontal areas for older compared to younger participants. Discussion. Behavioral results confirm that older participants have difficulties with the implementation of proactive control that is associated to decreased brain activity (compared to young participants) in areas underlying Stroop performance. However, the recruitment of supplementary frontal areas we observed in the reactive control condition suggests compensation processes. So, aging seems to differentially affect the neural networks associated to the various kinds of cognitive control. [less ▲]

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See detailLe donné phénoménal de Tim Crane
Gauvry, Charlotte ULg

Conference (2015, May 28)

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See detailThe hot Jupiter WASP-­121 b: A planet heading towards its doom
Delrez, Laetitia ULg

Conference (2015, May 28)

We present here the discovery by the WASP-South survey, in close collaboration with the Euler and TRAPPIST telescopes, of WASP-121 b, a new remarkable short-period transiting hot Jupiter. WASP-121 b is a ... [more ▼]

We present here the discovery by the WASP-South survey, in close collaboration with the Euler and TRAPPIST telescopes, of WASP-121 b, a new remarkable short-period transiting hot Jupiter. WASP-121 b is a very inflated (1.86 Rjup) Jupiter-mass (1.18 Mjup) planet that transits every 1.27 days a bright active F6V star. A notable property of WASP-121b is that its orbital semi-major axis is only 15% larger than its Roche limit, which suggests that the planet might be close to tidal disruption. Furthermore, its large size and extreme irradiation (7.1 10^9 erg s^-1 cm^-2) make it an excellent target for atmospheric studies via secondary eclipse observations. Using the TRAPPIST robotic telescope, we indeed detect its thermal emission in the z’-band at better than ~4sigma, the measured occultation depth being 603+-130 ppm. This measurement is a first for a ground-based 60cm telescope. Finally, from a measurement of the Rossiter-McLaughlin effect with the CORALIE spectrograph, we infer a sky-projected spin-orbit angle of 257.8+-6 deg. This result indicates a significant misalignment between the spin axis of the host star and the orbital plane of the planet, the planet being in a nearly polar orbit. [less ▲]

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See detailEnvironmental impact assessment of rail freight intermodality
Merchan Arribas, Angel ULg; Belboom, Sandra ULg; Léonard, Angélique ULg

in Rasouli, Soora; Timmermans, Harry (Eds.) Current issues in transportation research - Proceedings of the BIVEC/GIBET transport research days 2015 (2015, May 28)

The European Commission’s White Paper on transport (European Commission, 2011) seeks to achieve an efficient and sustainable balance between the various transport modes. Environmental impact studies on ... [more ▼]

The European Commission’s White Paper on transport (European Commission, 2011) seeks to achieve an efficient and sustainable balance between the various transport modes. Environmental impact studies on intermodality transport show that rail freight transport is the land-based transport that has a higher environmental performance compared to intermodal road-rail and all-road transport (Fries and Hellweg, 2014), especially when electrified railway is used (Spielmann and Scholz, 2005). Life Cycle Assessment (LCA) methodology allows us to model as best as possible the environmental impacts of several pollutants in numerous categories. For other categories such as accident damages, noise impact and land use, new developments have to be performed. For the environmental impact assessment, all life cycle phases of rail freight transport operation, rail infrastructure, and rail equipment are taken into account (Spielmann et al., 2007). [less ▲]

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See detailThe more you know...........various approaches in the analysis of tools from Liang Bua, Flores Indonesia
Lentfer, Carol ULg; Stephenson, Birgitta; Cnuts, Dries ULg et al

Conference (2015, May 28)

Chipped stone flakes from sedimentary deposits from the Liang Bua site, Flores, Indonesia have been found in association with faunal remains and skeletal remains identified as Homo floresiensis. Use-wear ... [more ▼]

Chipped stone flakes from sedimentary deposits from the Liang Bua site, Flores, Indonesia have been found in association with faunal remains and skeletal remains identified as Homo floresiensis. Use-wear and well-preserved organic residues on these flakes provide an opportunity to understand subsistence and behaviour of Homo floresiensis by determining how they were manipulated and what they were used for. This paper describes the analytical techniques including various microscope and staining methodologies used in residue analyses. It compares the efficacy and describes the outcome of these techniques in relation to the functional analysis of the Liang Bua lithic assemblage. [less ▲]

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See detailExecutive functions in normal aging: Impact of cognitive reserve and objective physical activity
Gilsoul, Jessica ULg; Simon, Jessica ULg; Collette, Fabienne ULg

Poster (2015, May 28)

It is now acknowledged that there exists a large inter-individual variability in age-related cognitive changes. According to Stern (2009), the cognitive reserve built up throughout the life span will make ... [more ▼]

It is now acknowledged that there exists a large inter-individual variability in age-related cognitive changes. According to Stern (2009), the cognitive reserve built up throughout the life span will make seniors more or less resilient to the deleterious effects of aging on cognition, with seniors having a high level of cognitive reserve being more prone to successfully cope with cognitive and neuronal changes. Currently, few studies have focused on the specific effects of different factors of cognitive reserve on cognition. Consequently, the objective of this study is to determine the impact of four determinants of cognitive reserve on executive functions in normal aging. Sixty-eight healthy participants aged 60 to 80 were enrolled. Regarding executive functions, Inhibition (Stroop test, Hayling test, TAP Incompatibility subtest), Shifting (TAP Flexibility subtest, Plus-Minus task), and Updating (Letter-Number Sequencing subtest from MEM III, Letter memory task, 2-back task) were assessed (Miyake et al., 2000). Cognitive reserve was measured by questionnaires assessing educational level, occupation, leisure activities and physical activity. Moreover, an accelerometer allowed quantitative measure of physical activity by recording body movements during two weeks. Group comparisons (p<0.05) showed that seniors with a high level of cognitive reserve (measured by a global composite z-score) have better updating abilities (Letter memory task and updating composite score). In order to test the influence of each cognitive reserve factor on executive functions, simple linear regressions (p<0.05) were performed. The results showed that the educational level accounts for a significant part of the variance in flexibility (TAP Flexibility) and updating (Letter-Number sequencing, 2-back and composite score). The occupational level accounts significantly for the variance of the updating composite score. Regarding the quantitative physical activity, the mean number of minutes per day in moderate or intense physical activity significantly predicted the updating composite score. These results indicate that the level of cognitive reserve is related to abilities in some executive tests, particularly updating abilities. Importantly, all aspects of cognitive reserve are not associated with the three executive processes. This indicates a specificity of the protective effect of cognitive reserve on executive abilities. [less ▲]

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See detailApplication du plan d’expérience de Box-Behnken et de la méthodologie des surfaces de réponses pour optimiser une méthode de quantification de phyto-œstrogènes dans les fourrages
Daems, Frédéric ULg; Lognay, Georges ULg; Romnee, Jean-Michel et al

Conference (2015, May 27)

Dans le cadre d’un projet de valorisation des prairies, intitulé « PhytoHealth », une méthode d’analyse quantitative constituée d’une étape d’extraction à l’aide d’un bain à ultrasons, suivi d’une ... [more ▼]

Dans le cadre d’un projet de valorisation des prairies, intitulé « PhytoHealth », une méthode d’analyse quantitative constituée d’une étape d’extraction à l’aide d’un bain à ultrasons, suivi d’une hydrolyse enzymatique et d’une analyse par UPLC®-MS/MS a été développée pour assurer le dosage de phyto-œstrogènes dans les fourrages. Pour alléger l’optimisation de la préparation des échantillons, la méthodologie des surfaces de réponses a été utilisée. Un plan d’expérience de Box-Behnken a été appliqué aux étapes d’extraction et d’hydrolyse. Parmi les différents facteurs pris en compte, les impacts de la nature du solvant utilisé lors de l’extraction ainsi que la température et le pH lors de l’hydrolyse, ont clairement pu être mis en évidence. L’ensemble des données générées a également permis de définir des conditions optimales d’extraction et d’hydrolyse pour chacun des composés. Ces conditions n’étant pas identiques pour chacun d’entre eux, un compromis a été trouvé afin de pouvoir analyser l’ensemble de ces composés simultanément. L’ensemble de la méthode a ensuite été validée selon les recommandations de l’EMA/CVMP/VICH/463202/2009, pour confirmer sa fiabilité et robustesse. Cette dernière, combinée au model d’ensilage en sacs sous vide, a permis pour la première fois de suivre la cinétique d’évolution de 4 phyto-œstrogènes (daidzéine, génistéine, formononétine et biochanin A) durant une période d’ensilage. [less ▲]

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See detailTel Quel, Change et Poétique en 1970 : "l'affaire de Lausanne"
Lorent, Fanny ULg

Conference (2015, May 27)

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See detailValidation d'une méthode d'analyse quantitative de l'équol par UPLC®-MS/MS dans le lait de vache - Application aux laits commercialisés en Wallonie (Belgique)
Daems, Frédéric ULg; Lognay, Georges ULg; Romne, Jean-Michel et al

Conference (2015, May 27)

Dans le cadre d’un projet intitulé «PhytoHealth », une méthode d’analyse quantitative de l’équol dans le lait a été développée et validée selon les recommandations de l’EMA/CVMP/VICH/463202/2009. Celle-ci ... [more ▼]

Dans le cadre d’un projet intitulé «PhytoHealth », une méthode d’analyse quantitative de l’équol dans le lait a été développée et validée selon les recommandations de l’EMA/CVMP/VICH/463202/2009. Celle-ci est constituée d’une étape d’hydrolyse enzymatique, suivie d’une double extraction liquide/liquide et d’une analyse par chromatographie liquide ultra performante couplé à un spectromètre de masse en tandem (UPLC®-MS/MS). Une fois les différents paramètres tels que la fiabilité, sensibilité et/ou robustesse de la méthode confirmées, celle-ci a permis, pour la première fois, d’estimer la teneur en équol d’ échantillons de laits commercialisés en Wallonie. Une Cinquantaine de laits ont été prélevés aléatoirement dans les commerces durant une période définie. Tous les échantillons possédaient une teneur en équol ≥ 10ng.mL-1. En comparant les valeurs moyennes, on a constaté qu’il n’y avait pas de différence entre les 4 catégories de laits analysés (entier, demi-écrémé, écrémé et cru). Par contre, une différence hautement significative a pu être observée entre les laits provenant de la filière biologique et ceux de la filière conventionnelle. Dans le premier cas, les teneurs varient entre 10 et 50 ng.mL-1 par contre, dans le second, elles varient entre 70 et 130 ng.mL-1. Cet impact de la filière biologique sur la teneur en équol dans les laits a pu être confronté à d’autres études européennes et confirmé. [less ▲]

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See detailControl of nuclear sample polarization using optical pumping and radio-frequency methods
Lenaers, Florence ULg; Glover, Rohan ULg; Bastin, Thierry ULg

Conference (2015, May 27)

Laser-cooled and trapped radioactive isotopes are now being used to probe the properties of the weak interaction in nuclear beta decay. In this context, it is essential that one be able to control the ... [more ▼]

Laser-cooled and trapped radioactive isotopes are now being used to probe the properties of the weak interaction in nuclear beta decay. In this context, it is essential that one be able to control the nuclear polarization of the atomic samples. We present two polarization/depolarization schemes for argon-35, whose mirror transition to chlorine-35 is a particularly sensitive candidate for precision measurements in nuclear beta decay. [less ▲]

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See detailDense-lineability in classes of ultradifferentiable functions
Esser, Céline ULg

Conference (2015, May 27)

The Denjoy-Carleman classes are spaces of smooth functions which satisfy growth conditions on their derivatives defined through weight sequences. In this talk, given a Denjoy-Carleman class E of Beurling ... [more ▼]

The Denjoy-Carleman classes are spaces of smooth functions which satisfy growth conditions on their derivatives defined through weight sequences. In this talk, given a Denjoy-Carleman class E of Beurling type that strictly contains another non-quasianalytic class F of Roumieu type, we handle the question of knowing how large the set of functions in E that are nowhere in the class $F$ is. In particular, we prove the dense-lineability of the set of functions of $E$ which are nowhere in F. Consequences for the Gevrey classes are also given. We extend then these results to the case of classes of ultradifferentiable functions defined imposing conditions on their Fourier Laplace transform using weight functions. [less ▲]

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See detailVenus nightglow intensity and solar activity: any correlation?
Soret, Lauriane ULg; Gérard, Jean-Claude ULg

Conference (2015, May 26)

We examine if any correlation is observed between the brightness of the O2 nightside airglow and the EUV solar irradiance using the full database of VIRTIS IR images. We conclude that, as was the case for ... [more ▼]

We examine if any correlation is observed between the brightness of the O2 nightside airglow and the EUV solar irradiance using the full database of VIRTIS IR images. We conclude that, as was the case for the NO airglow observed during the Pioneer Venus mission, no response to solar activity is observed. [less ▲]

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See detailProcess-based method for groundwater resource vulnerability mapping with regards to solute contamination at the surface
Popescu, Cristina; Brouyère, Serge ULg; Orban, Philippe ULg et al

Conference (2015, May 26)

Numerous groundwater vulnerability methods have been developed taking into consideration a variable number of factors. The most common techniques are based on calculation of an index expressing the ... [more ▼]

Numerous groundwater vulnerability methods have been developed taking into consideration a variable number of factors. The most common techniques are based on calculation of an index expressing the protective effect of underground formations overlying the groundwater resource. However, it has been shown that different overlay and index methods applied to the same system can yield dramatically dissimilar results (among others, Gogu et al., 2003). The limitation of most of these methods is related to their use of a qualitative definition of groundwater vulnerability, as opposed to a definition based on a quantitative description of contaminant migration. A process-based point of view is proposed and based on three factors describing a pollution event (Brouyère et al., 2001): (1) the transit time from the source to the target, (2) the duration of the contamination breakthrough at the target, (3) the ratio between the maximum concentration at the target to the released concentration at the contamination source. The assessment can then be based on the impulse response at the ‘target’ to a Dirac-type solicitation (point, unit mass, instantaneous source of pollution), considering only physical hydrodispersive processes for intrinsic vulnerability and both physical and biochemical processes for specific vulnerability. The breakthrough curve obtained after a vertical transfer through the overlying layers can be computed pixel by pixel. Automatically processing the columns with identical characteristics, 1D partially saturated flow and solute transport computations are performed. Different maps are obtained for the three above mentioned factors. On the basis of these results, different vulnerability maps can be built according to the weighting coefficients agreed by the local community or decision makers. This concept allows a clear distinction between conventional aspects and process-based results in the building of a final vulnerability indicator. This methodology has the further advantage to consider the possible impact of runoff conditions occurring at the land surface and possibly leading to lateral contamination of groundwater through downstream preferential infiltration features. To solve this problem, Popescu et al. (2004 & 2008) and Dassargues et al. (2009) proposed a method for quantifying a lateral “dangerosity” coefficient using runoff coefficients based on land use, slopes, and soil properties. A test application is illustrated on a case-study located in a limestone basin in Belgium. [less ▲]

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See detailDe la spécification à la création de nouvelles catégorisations sociales: Le cas de francophones vivant en Flandre et de néerlandophones vivant en Wallonie
Dassargues, Alix ULg

Conference (2015, May 26)

Nos recherches doctorales visent à étudier la manière dont des individus en situation d’allophonie « illégitime » se catégorisent socialement. Puisqu’aucune catégorie identitaire légitime (c.-à-d ... [more ▼]

Nos recherches doctorales visent à étudier la manière dont des individus en situation d’allophonie « illégitime » se catégorisent socialement. Puisqu’aucune catégorie identitaire légitime (c.-à-d. institutionnalisée par les dictionnaires, les médias, les politiciens ou autres instances légitimatrices (Bourdieu 1982)) ne rend compte de la situation de francophones vivant en Flandre (région belge unilingue néerlandophone) et de néerlandophones vivant en Wallonie (région belge unilingue francophone excepté une petite communauté germanophone institutionnellement reconnue et territorialisée), ces individus conceptualisent le champ social de façon originale afin qu’il corresponde à leurs propres expériences de vie (Harder 2010 : 18). En se basant sur des principes tels que la légitimité d’un lexème dans l’espace discursif ou encore le caractère idiolectal ou non d’une catégorisation, nous nous proposons d’observer les modes de conceptualisation de l’identité par des locuteurs particulièrement aptes à formuler des catégorisations originales du champ social puisque leurs expériences de vie ne font pas l’objet de catégorisations légitimes. À partir de transcriptions d’entretiens semi-directifs, nous avons examiné le discours de témoins afin d’analyser leurs conceptualisations du champ social à travers les catégorisations qu’ils emploient. Nous prenons en compte les catégories légitimes et illégitimes citées dans les témoignages selon leur institutionnalisation (présence ou non dans les dictionnaires et dans les discours médiatiques) et la manière dont elles sont considérées par les locuteurs (catégorie considérée comme légitime ou non par les locuteurs). De la sorte, une typologie de nouvelles catégorisations identitaires a pu être établie sur la base d’une analyse linguistique : spécification d’un lexème légitime par une proposition relative , spécification d’un signifié par un redoublement de certains signifiants légitimes , spécification d’un signifié par l’instauration d’une gradation dans l’adéquation avec une catégorie légitime (stéréotype institutionnalisé) , modifications de signifiés dans des catégorisations légitimes , création de nouvelles catégorisations à partir d’adjectifs et de lexèmes légitimes , création de métaphores en transposant l’expérience d’un domaine conceptuel des catégories sociales (cf. Lakoff & Johnson 1980). Cette recherche interdisciplinaire suggère que la construction de sens s’établit à partir d’autres connaissances déjà organisées entre elles (Harder 2010:113) et partagées par une communauté d’individus. En choisissant le thème ambitieux de l’identification (ou la catégorisation) de soi et des autres, cette recherche permet également de transposer les connaissances de la linguistique cognitive au domaine social. Ainsi, elle confirme notamment que le modèle sémantique basé sur un prototype (Rosch 1978; Lakoff 1987) est adéquat pour rendre compte de la construction individuelle du sens dans le champ social. [less ▲]

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See detailPropagation of uncertainties in the modelling of MEMS resonators (using a 3-scale probabilistic approach)
Lucas, Vincent ULg; Wu, Ling ULg; Golinval, Jean-Claude ULg et al

Conference (2015, May 26)

In order to ensure the accuracy of MEMS vibrometers, the first resonance frequency should be predicted at the design phase. However, this prediction is subjected to randomness: there is a scatter in the ... [more ▼]

In order to ensure the accuracy of MEMS vibrometers, the first resonance frequency should be predicted at the design phase. However, this prediction is subjected to randomness: there is a scatter in the reached value resulting from the uncertainties involved in the manufacturing process. The purpose of this work is to take into account these uncertainties of the microstructure. The objective is a non-deterministic model that can be used since the design stage. The material is the source of uncertainties: the beam resonator is made of a polycrystalline 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 of the resonance frequency to be computed. However this methodology is computationally expensive due to the number of degrees of freedom required to study one sample, motivating the development of a computationally efficient method. Towards this end a 3-scales stochastic model for predicting the resonance frequency of a micro-beam made of a polycrystalline linear anisotropic material is described. At the lower scale, we model the micro-structure with micro-volume elements. Due to the small-scale involved, the representativity of these micro-volume elements is not achieved and thus Statistical Volume Elements (SVE) are considered. These SVEs are generated under the form of a Voronoï tessellation, each grain being assigned a random orientation. Computational homogenization is applied over the SVEs, along with a Monte-Carlo procedure, to obtain a stochastic characterization of the elasticity tensor at the second scale of interest, the meso-scale. The spatial correlation between SVEs is also estimated. A generator based on spectral methods is implemented. Afterwards, using a stochastic finite element method, these meso-scale uncertainties are propagated by taking account of the spatial correlation up to the higher scale to predict the probabilistic behavior of the MEMS resonator. [less ▲]

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See detailSensitivity and vulnerability to groundwater overexploitation by a ‘pressure state impact’ and process based approach
Beaujean, Jean; Lemieux, Jean-Michel; Therrien, René et al

Conference (2015, May 26)

A methodology is developed for proposing a groundwater vulnerability assessment in a Pressure-State-Impact causal chain that is familiar to decision makers. The ‘Driver Pressure State Impact Response’ ... [more ▼]

A methodology is developed for proposing a groundwater vulnerability assessment in a Pressure-State-Impact causal chain that is familiar to decision makers. The ‘Driver Pressure State Impact Response’ (DPSIR) framework, for describing interactions between society and the environment, defines a chain of Drivers that exert Pressures on the State of a given resource, such as groundwater, which then generates an Impact that will require an appropriate Response (Kristensen, 2004). The method is here based on the calculation of sensitivity coefficients for a user-defined groundwater state for which several physically-based indicators are proposed. These sensitivity coefficients reflect the easiness with which the groundwater state transmits pressures into impacts. They are grouped into a vulnerability matrix of pressures and impacts that quantify vulnerability for every combination of causal links identified in the DPSIR chain. For that reason, the sensitivity coefficients are converted to vulnerability, using the concept of ‘transgressing a given threshold’, which is commonly used in socioeconomic sciences (Luers et al. 2003). The concept of ‘rising above a given concentration threshold’ can be used for groundwater quality issues. The concept of ‘falling below a given piezometric head threshold’ can be used for groundwater quantity issues as aquifer overexploitation problems. Outside the careful selection of the sensitivity analysis method that can significantly influence the computational effort (Beaujean et al., 2013), emphasis is given to the illustration of the general methodology on a simple groundwater quantity case (of an alluvial aquifer with concerns related to water supply) demonstrating the potential use of this general and physically based vulnerability assessment method. While the methodology is general, the choice of causal chains has to be made prior to the calculation. The vulnerability is also related to a damaged state and is related to the ‘distance’ between the current state and a given threshold. This choice is arbitrary such that the vulnerability is sensitive to the choice of the threshold. [less ▲]

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See detailA stochastic multiscale analysis for MEMS stiction failure
Hoang Truong, Vinh ULg; Wu, Ling ULg; Golinval, Jean-Claude ULg et al

Conference (2015, May 26)

Stiction is a major failure in microelectromechanical system (MEMS) devices in which two contacting surfaces can remain stuck together because of the adhesive forces, such as van der Waals forces and ... [more ▼]

Stiction is a major failure in microelectromechanical system (MEMS) devices in which two contacting surfaces can remain stuck together because of the adhesive forces, such as van der Waals forces and capillary forces. Stiction is a multiscale problem which is characterized by three different lengths: the MEMS device characteristic length, the roughness of the contacting surfaces, and the distance range of the adhesive forces. Because MEMS surfaces roughness and adhesive force distances are of comparable scales, the randomness in the contacting surfaces can result in important uncertainties on the interacting forces, and in turn lead to a scatter in the MEMS structural behavior. The purpose of this work is to quantify the uncertainties on the macro stiction behavior of a MEMS structure due to the randomness in its contacting surfaces. A full analysis, such as the combination of a Monte-Carlo simulation to generate random surfaces combined with finite element (FE) analyses to model the stiction behavior, is expensive in terms of the computational cost due to the difference in the scales between the macro characteristic length and the distance range of the adhesive forces. Thus, in this work, we develop a stochastic multiscale analysis. At the micro scale, the uncertainties in the interacting forces between two rough surfaces are investigated. The power spectral density function of the surface is characterized from experimental topology measurements, and interacting surfaces are then generated as Gaussian random surfaces. For each generated random surface, the interacting adhesive forces are calculated by using a modified Dejarguin-Muller-Toporov (DMT) model. The resulting adhesive contact forces can be integrated using the finite element method at the structural scale by associating to each discretized contacting point a sampled surface. We then use the Monte-Carlo method to quantify the uncertainties in the stiction behavior of the MEMS device. [less ▲]

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See detailAbout the Regularity of Cantor's Bijection
Simons, Laurent ULg; Nicolay, Samuel ULg

Conference (2015, May 25)

In 1878, Cantor proved that there exists a one-to-one correspondence between the points of the unit line segment [0,1] and the points of the unit square [0,1]². Since this application is defined via ... [more ▼]

In 1878, Cantor proved that there exists a one-to-one correspondence between the points of the unit line segment [0,1] and the points of the unit square [0,1]². Since this application is defined via continued fractions, it is very hard to have any intuition about its smoothness. In this talk, we explore the regularity and the fractal nature of Cantor's bijection, using some notions concerning the metric theory and the ergodic theory of continued fractions. This talk is based on a joint work with S. Nicolay. [less ▲]

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See detailCharles Juliet : Du portrait a-posteriori à l’écriture de soi L’adresse à la mère comme tentative de désenfouissement dans Lambeaux
Vandormael, Thomas ULg

Conference (2015, May 25)

Lambeaux propose un diptyque de portraits. Dans la première partie, celui de la mère biologique. Dans la seconde, celui de l’auteur lui-même et au sein de celui-ci, enfin, le portrait de la mère adoptive ... [more ▼]

Lambeaux propose un diptyque de portraits. Dans la première partie, celui de la mère biologique. Dans la seconde, celui de l’auteur lui-même et au sein de celui-ci, enfin, le portrait de la mère adoptive. La dimension vocative explicite de la narration en constitue à la fois l’originalité et le paradoxe. Le recours au « Tu » dans l’ensemble du texte fait advenir une poétique de l’adresse en laquelle se cristallise la spécificité du récit de filiation propre à l’autofiction de la littérature contemporaine : différent du simple devoir de mémoire ou encore de la - très en vogue - commémoration, il se situe plutôt du côté de la restitution, à laquelle il y a deux sens à donner : à la fois reconstituer ce qui fut et s’est défait, et rendre leur existence à ceux qui s’en sont trouvés dépouillés en faisant apparaître ce qui demeure enfoui et dont on n’a pu hériter. Pour répondre au silence d’une mère qu’il n’a pas connue et qui elle-même n’a pas pu s’exprimer, faute d’accès au langage ou d’une présence pour l’écouter, Juliet choisit l’instantané et l’immédiateté d’un discours d’interpellation au présent et la forme du dialogue avec les morts, forcément toujours en partie déjà voué à l’échec. Dès lors, notre propos souhaite interroger comment le choix du vocatif permet un dédoublement fécond du sujet,faisant advenir une relation de soi à soi qui déjoue les processus classiques de l'autobiographie. [less ▲]

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See detailGestion des déchets nucléaires en France et en Belgique: Quelle place pour la critique ?
Parotte, Céline ULg

Conference (2015, May 25)

Depuis les années 1970, avec la multiplication des controverses scientifiques (Callon, Lascoumes et Barthe 2001), souvent liées à des mouvements pacifistes en environnementalistes ; nous assistons à la ... [more ▼]

Depuis les années 1970, avec la multiplication des controverses scientifiques (Callon, Lascoumes et Barthe 2001), souvent liées à des mouvements pacifistes en environnementalistes ; nous assistons à la naissance d’un flux d’incertitude et de critique politico-sociale, dirigée principalement vers le monde scientifique, sa production et ses hésitations. Il est malaisé de prévoir si cela mènera à une réelle désolidarisation des notions de science, technologie et progrès, mais il reste à supposer que cette critique permettra une gestion plus réflexive des effets majeurs du développement scientifique et technologique (Schot et Rip 2009). En d’autres termes, bien que les liens entre les idéologies du progrès et de la technologie restent très souvent puissants et non remis en question, on assiste au même moment à une critique sociale des conséquences sur le processus de gestion des choix technologiques qui s’y rapportent. Cette contribution propose de s’attarder sur le cas de la gouvernance socio technique de la gestion des déchets hautement radioactifs depuis le « tournant participatif » opéré dans les années 90 en France et en Belgique. Il s’agit de poser un regard critique sur l’apparition d’un nouveau mode de gouvernance plus participatif (au travers de l’inclusion de nouveaux acteurs) et ses conséquences. Dans quelle mesure ceux-ci redéfinissent-ils les positionnements du monde scientifique au sein du processus décisionnel ? Comment le monde scientifique reçoit-il les critiques qui lui sont adressées ? Plutôt que des tendances globales, cette contestation témoigne le plus souvent d’une mosaïque d’activités critiques dynamiques, concurrentes ou complémentaires dont les effets semblent faire vaciller — ou à tout le moins mettre sous tension — l’organisation, les routines et les institutions des sociétés modernes (Delvenne 2011). Cette mosaïque reflète le dynamisme des acteurs sociaux qui propagent leurs agendas et défendent leurs intérêts à travers la négociation de concessions, l’enchevêtrement de décisions et la cristallisation de rapports de force. En d’autres termes, les avancées d’un projet comme la gestion des déchets nucléaires ne sont pas la progression inéluctable d’un processus uniformément accepté par toutes les tendances de la société. En réalité, il existe une multitude d’acteurs qui influencent sans cesse la nature de ses contours. Ces acteurs sociaux bénéficient d’espaces politiques et institutionnels divers pour exprimer leurs préférences et tenter de transformer durablement les critiques qu’ils formulent en actions politiques qui trouvent un écho plus large au sein de la société. [less ▲]

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See detailElectric current crowding in nanostructured conductors
Silhanek, Alejandro ULg

Conference (2015, May 24)

When current stream lines are forced to depart from their rectilinear trajectory due to the presence of an obstacle, they conglomerate at the sharp bends encountered on their paths. The consequent current ... [more ▼]

When current stream lines are forced to depart from their rectilinear trajectory due to the presence of an obstacle, they conglomerate at the sharp bends encountered on their paths. The consequent current crowding is present in normal metals as well as in superconductors and has been, since long ago, identified as a key player in electromigration phenomena leading to failure in integrated circuit interconnects while might also be at the origin of local ablation in planar plasmonic structures. More recently, current crowding has been recognized as an important factor limiting the performance of superconducting single-photon detectors, leading to flux quanta motion rectification, or being a source of unwanted ratchet signal and depletion of surface barriers for magnetic flux penetration. In this talk, we will also show that in nanostructured superconductors at low temperatures, current crowding can trigger abrupt flux avalanches developing well defined geometrical patterns. Our experimental findings are backed up to the finest details, by simulations based on a phenomenological thermomagnetic model which, in turn, can be used to predict such complex structures and, given its reliability, allows one to estimate physical variables of more difficult experimental access, such as the local values of temperature and electric field. [less ▲]

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See detailDo large scale restoration projects reduce within-species traits variability?
Harzé, Mélanie ULg; Monty, Arnaud ULg; Mahy, Grégory ULg

Conference (2015, May 23)

Dry calcareous grasslands represent local biodiversity hotspots of European temperate regions. They have suffered intensive fragmentations due to due to the abandonment of traditional agropastoral systems ... [more ▼]

Dry calcareous grasslands represent local biodiversity hotspots of European temperate regions. They have suffered intensive fragmentations due to due to the abandonment of traditional agropastoral systems and the resulting encroachment, reforestation, urbanization or transformation into arable lands. In order to preserve and enhance their ecological value, a series of ecological restoration projects have been implemented throughout Europe (LIFE+). As habitats restoration costs can be prohibitive, actions should demonstrate their success. In the face of environmental changes, restored populations should possess attributes necessary for adaptive evolutionary changes allowing them to persist over the long term. Intra-population functional variability expresses the range of possible trait values of a species living in a heterogeneous environment. It results notably from genetic diversity and phenotypic plasticity and enables species survival, growth and reproduction under various environmental conditions. In Belgium, three European LIFE projects have taken place between 2000 and 2009, restoring more than 400 hectares of calcareous grasslands. Restorations have mainly been evaluated in terms of plant species diversity and community composition. Though it is expected to be of crucial importance for species evolutionary potential, the restoration of the entire range of environmental heterogeneity and the resulting intra-population functional variability of restored population have so far not been assessed. We compared the intra-population variability of functional traits (specific leaf area (SLA) and maximum vegetative height) of 10 restored and 10 reference populations of Potentilla neumanniana (30 individuals per populations). We characterized abiotic and biotic conditions by measuring soil depth, sun exposure, bare ground cover and mean vegetation height around each sampled individual. Our main results showed that the range of within-species functional variability was restored in our study area. We will conclude with implications for the evolutionary potential of restored populations and for future ecological restoration projects. [less ▲]

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See detailAlain Robbe-Grillet face à l'entretien journalistique : paradoxes
Lorent, Fanny ULg

Conference (2015, May 22)

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See detailModulatory effects of Ruthenium (II)-based complexes on oxidative stress induced by activated HL60 cells and Neutrophils
Mouithys-Mickalad, Ange ULg; Collienne, Simon ULg; Franck, Thierry ULg et al

Conference (2015, May 22)

There is a growing interest on the use of metal-based chemotherapeutic agents to fight different types of cancers [1]. The most used family of the organometallic compounds is platinum derivatives whose ... [more ▼]

There is a growing interest on the use of metal-based chemotherapeutic agents to fight different types of cancers [1]. The most used family of the organometallic compounds is platinum derivatives whose Cisplatin (CisPt) is the lead compound used for the treatment of various cancers including lung, testis, gastric, breast, etc. Nevertheless, beside its recognized therapeutic effects, side effects such as gastric toxicity and acute kidney failure were observed during the treatment, limiting its clinical use. Other compounds are currently studied and among them, Ruthenium (Ru) complexes have gained more importance for their less toxicity and lower aggressive effect on healthy tissues than CisPt. Ru-complexes are also more resorbed and excreted [2]. Numerous studies focused on the mechanisms of action of Ruthenium compounds to fight cancer, including antioxidant or pro-oxidant activity. During inflammation, activation and infiltration of neutrophils contribute to oxidant stress playing a crucial role in tumor development. Likewise, the degranulation of neutrophil causes the release of myeloperoxidase (MPO) which reacts with H2O2 to catalyze redox reactions. A therapeutic target to control inflammation is the modulation of oxidant enzymes and cells involved in radical species production and redox reactions. Because Ruthenium compounds can easily enter into cancer cells, a series of Ru(II)-complexes newly synthesized were used for this purpose. They were first tested for their radical scavenging activities using ABTS and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. Amongst them, compound 1 (LD0436) and compound 2 (LD04037) were then studied for their ability to modulate the reactive oxygen species (ROS) production by inflammatory cells like human promyelocytic leukemia cell line (HL 60) and neutrophils (PMN) using fluorescence, chemiluminescence (CL) and electron spin resonance ESR techniques. The toxicity of those Ru-complexes against HL-60 and neutrophils was checked using Trypan blue exclusion assay. Altogether, CL and ESR findings indicate that both complexes 1 (LD0436) and 2 (LD0437) exhibit a dose-dependent inhibitory activity compared to CisPt, gallic acid, curcumin and quercetin, which were taken as reference molecules in the different systems investigated. Similarly, the tested complexes also display an antioxidant profile on the substrate oxidation catalyzed by peroxidase such as MPO mainly involved in acute and chronic inflammatory situations. 1: (RuCl(p-Cymen)(S2C.IDip)]+(PF6)-], 2: (RuCl(p-Cymen)(S2C.Icy)]+(PF6)-] References: 1. Ceresa C, Brawin A, Cavaletti G, Trinidad A et al., (2014) Current Medicinal Chemistry 20(21), 2237-2265. 2. Liu, Y, Zhang X, Zhang R, et al., (2011) European Journal of Inorganic Chemistry. 1974-1980. [less ▲]

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See detailExploration de facteurs cognitifs et thymiques en lien avec les symptômes psychotiques : Analyses en clusters.
Laloyaux, Julien ULg; Laroi, Frank ULg; Nuyens, Filip et al

Conference (2015, May 22)

Introduction Il est maintenant reconnu qu’il existe différentes trajectoires possibles au développement et au maintien des symptômes psychotiques tels que les hallucinations et les idées délirantes. Ces ... [more ▼]

Introduction Il est maintenant reconnu qu’il existe différentes trajectoires possibles au développement et au maintien des symptômes psychotiques tels que les hallucinations et les idées délirantes. Ces phénomènes sont également en lien avec différents mécanismes cognitifs (e.g. style d’encodage, impulsivité) et facteurs thymiques (e.g. anxiété, dépression). Cependant, le poids de ces facteurs peut certainement varier en fonction des différentes trajectoires. Objectifs L’objectif de cette étude est d’explorer l’impact de différents facteurs cognitifs et thymiques sur les symptômes psychotiques dans un large échantillon issu de la population normale afin d’essayer d’en faire ressortir des profils différents avec l’aide d’analyses en clusters. Les mesures suivantes ont été incluses : Launay-Slade Hallucinations Scale, Schizotypal Personality Questionnaire-Brief, Peters et al. Delusions Inventory, UPPS Impulsive Behavior Scale, Beck Depression Inventory, State-Trait Anxiety Inventory (trait). [less ▲]

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See detailMake the ureter your friend
Bonnet, Pierre ULg

Conference (2015, May 22)

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See detailQuels profils caractérisés par l'humeur, l'activation comportementale et les stratégies de régulation émotionnelle pouvons-nous identifier dans une population adulte ?
Wagener, Aurélie ULg

Conference (2015, May 22)

The behavioural model of depression put forward that the level of activities in depressed patients decreases which maintains their low mood. Depressed patients are also known to use non-adaptive cognitive ... [more ▼]

The behavioural model of depression put forward that the level of activities in depressed patients decreases which maintains their low mood. Depressed patients are also known to use non-adaptive cognitive coping strategies (e.g. rumination, catastrophizing). Previous research underlined that cognitive coping strategies predict the level of activation (non-adaptive cognitive coping strategies predict a low level of activation). According to the dimensional approach of psychopathology, we hypothesised that sub-groups of depressed and non-depressed adults could be identified depending on their level of activation and the kind of cognitive coping strategies they use. In order to test this hypothesis, we investigated the relationships between the level of activation, the cognitive coping strategies, anxiety and depression with a cluster-analysis approach. 762 adults (530 women, 232 men; mean age= 31.54, SD= 12.08) completed an online survey assessing the above-mentioned variables with self-reports measures (BADS-SF, CERQ, BDI-II, STAI-Y B). Results identified four clusters that differed according to the level of activation, the cognitive coping strategies, the anxiety and the depression. For instance, one of the four classes highlighted that non-active depressed adults used catastrophizing and rumination contrary to another classes of active non-depressed ones. These results, providing interesting guidelines for psychological interventions, will be discussed further during the congress. [less ▲]

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See detailElectron paramagnetic resonance and fluorescence studies on potential anticancer properties of two new Ru(II) complexes : preliminary results
Collienne, Simon ULg; Terrak, Mohammed ULg; Mouithys-Mickalad, Ange ULg et al

Poster (2015, May 22)

Fight against cancer is a priority of today’s research. Since the discovery of the anticancer properties of cisplatin (CisPt) in 1965 by Rosenberg [1], the treatment of cancer by chemotherapy has known ... [more ▼]

Fight against cancer is a priority of today’s research. Since the discovery of the anticancer properties of cisplatin (CisPt) in 1965 by Rosenberg [1], the treatment of cancer by chemotherapy has known great improvements. Unfortunately, CisPt has several side effects and is not effective against all kinds of cancer. Nevertheless its use highlights the great potential of organometallic compounds in the treatment of cancer [2]. Here we investigated the potential anticancer properties of two new organometallic compounds based on ruthenium II : [RuCl(p-cymene)(S2C.IDip)]+(PF6)- and [RuCl(p-cymene)(S2C.ICy)]+(PF6)-, named as LDO436 and LDO437 respectively. [less ▲]

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See detailEffect of inulin and wheat bran in the creep feed of neonatal piglets
Li, Bing ULg; Leblois, Julie ULg; Bindelle, Jérôme ULg et al

Conference (2015, May 22)

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See detailBifurcation Analysis of Large-Scale Dynamical Systems Using the Harmonic Balance Method
Detroux, Thibaut ULg; Renson, Ludovic ULg; Masset, Luc ULg et al

Conference (2015, May 22)

The harmonic balance (HB) method has been widely used in the past few years, as a numerical tool for the study of nonlinear industrial models. However, in its classical formulation the HB method is ... [more ▼]

The harmonic balance (HB) method has been widely used in the past few years, as a numerical tool for the study of nonlinear industrial models. However, in its classical formulation the HB method is limited to the approximation of periodic solutions. The present paper proposes to extend the method to the detection and tracking of codimension-1 bifurcations in the system parameters space. As an application, the frequency response of a spacecraft and its bifurcations are studied, together with two nonlinear phenomena, namely quasiperiodic oscillations and detached resonance curves. [less ▲]

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

Conference (2015, May 21)

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

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See detailMaladaptive emotion regulation strategies and stress sensitivity mediate the relation between adverse life events and attenuated psychotic symptoms.
Laloyaux, Julien ULg; Dessart, Gregory; Van der Linden, Martial ULg et al

Poster (2015, May 21)

Introduction There is now solid evidence for a relation between Adverse Life Events (ALE) and psychotic symptoms in both patients with psychosis and in the general population. A recent study has shown ... [more ▼]

Introduction There is now solid evidence for a relation between Adverse Life Events (ALE) and psychotic symptoms in both patients with psychosis and in the general population. A recent study has shown that this relation may be partially mediated by stress sensitivity. However, other factors that may mediate this relation, such as emotion regulation strategies, have not yet been examined in the literature. Objective The aim of this study was to assess the mediation effect of both emotion regulation strategies and stress sensitivity in the relation between ALE and attenuated positive psychotic symptoms in the general population. Results Results demonstrated that the relation between ALE and attenuated positive psychotic symptoms (i.e. hallucinations and delusions) was mediated by maladaptive emotion regulations strategies. Discussion Although it is most likely that there are several possible trajectories leading to the formation of positive psychotic symptoms, the results of the present study suggest that one such trajectory may involve the maladaptive regulation of negative emotions alongside a certain vulnerability after experiencing highly distressing ALE. Hence, interventions aiming to enhance adaptive emotion regulation strategies and diminish the utilization of maladaptive strategies should be regarded as an integral part of psychological treatment schemes in the context of psychotic symptoms. Conclusion In summary, the present study demonstrated that the relation between ALE and attenuated positive psychotic symptoms is mediated by maladaptive emotion regulation strategies. [less ▲]

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See detailAssessing employees propensity to engage in OCB: incremental validity of SJT beyond personality.
Lothe, Benoit ULg; Hansez, Isabelle ULg; Scius, Anthony et al

Conference (2015, May 21)

This study presents the validation results of a SJT developed in collaboration with a Belgian french speaking mutual insurance company for the assessment of employees OCB. The purpose is to provide ... [more ▼]

This study presents the validation results of a SJT developed in collaboration with a Belgian french speaking mutual insurance company for the assessment of employees OCB. The purpose is to provide empirical evidence concerning the validity of using the SJT by examining the issues of OCB criterion validity, incremental validity beyond a personality inventory, applicant perception and SJT transparency level. The SJT was developed in-house and following relevant literature recommendations (Weekley, Ployhart & Holtz, 2006). Data were collected on 117 white-collar employees. Three other measurements were concurrently collected: OCB using Williams & Anderson (1991) self-reported scales, personality using the Gosling, Rentfrow & Swann (2003) ten item inventory (TIPI) and applicant perception using SPJS (Bauer, & al., 2001). An open-ended question was used to access the extent to which applicants are able to identify the SJT criteria. Results indicated that the SJT is a relevant predictor of OCB (r = .42; p<.001). The SJT also provides incremental explanation of the OCB criteria beyond the personality inventory (∆R² = .11; p<.001). There was in average an agreement about the acceptability of the SJT in terms of perceived procedural justice. No relationships were found between applicant ability to correctly identify the SJT criteria and SJT score or OCB self-rating. This study is to our knowledge among the first attempt to develop and validate a tool to fill the gap on how to predict employees OCB (Organ, Podsakoff & Podsakoff, 2010). Implications for the personnel selection and current limitations will be discussed. [less ▲]

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See detailAgroecology: Unity into diversity
Hatt, Séverin ULg; Artru, Sidonie ULg; Boeraeve, Fanny ULg et al

Poster (2015, May 21)

What does agroecology suggest ? Next to the theoretical agroecological principles, we present illustrative examples from farming practices, through the food system, up to the way of carrying agricultural ... [more ▼]

What does agroecology suggest ? Next to the theoretical agroecological principles, we present illustrative examples from farming practices, through the food system, up to the way of carrying agricultural research and education. [less ▲]

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See detailCombining remote sensing and ancillary data to improve species distribution models
Delangre, Jessica ULg; Radoux, Julien; Jacquemin, Floriane ULg et al

Poster (2015, May 21)

Correlative distribution models are increasingly used in biological conservation. They often require the compilation of various environmental attributes (climate, topography, land cover,…), which can be ... [more ▼]

Correlative distribution models are increasingly used in biological conservation. They often require the compilation of various environmental attributes (climate, topography, land cover,…), which can be very time-consuming. In the Lifewatch project, a database combining segmentation in homogeneous landscape units (“ecotopes”) and environmental attributes derived from regularly updated remote sensing data (land cover, potential solar energy,…) and other data sources (climate, topography,…) has been designed. Our aim was to assess the usefulness of this database for species distribution modelling and to propose further improvements. The distribution of ten species (four butterflies, three birds, two reptiles and one mammal) was modelled across Wallonia and model performance was assessed by Area Under the ROC Curve using the subsample approach. The models derived from ecotope segmentation and quantitative land cover attributes were compared to those obtained with a corresponding grid and a qualitative land cover database. The usefulness of ancillary data (soil properties, contextual attributes) was assessed to decide which variables should be integrated in the ecotope database. The results allowed us to assess and improve the relevance and accuracy of our database, which is a promising tool for species distribution modellers at the European scale. [less ▲]

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

Conference (2015, May 21)

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

Poster (2015, May 21)

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

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

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See detailThe impact of ageing on episodic memory encoding: an fMRI study
François, Sarah ULg; Angel, Lucie; Salmon, Eric ULg et al

Poster (2015, May 21)

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear ... [more ▼]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear to recruit prefrontal areas bilaterally when their encoding is successful, while in young adults this activation is found to be left-lateralized (b). In this study, we were interested in the differences between younger and older participant regarding cerebral activity during encoding depending on whether the item elicited recollection or familiarity during the recognition phase. Twenty young volunteers (aged 19 to 29 years old) and 19 older volunteers (aged 60 to 78 years old) were presented visual stimuli depicting objects. During a first fMRI session, they were asked to make a size judgement about them. Then, in a second phase, the subjects were shown the items previously encountered during the encoding phase, as well as distractors. Participants' task was to determine which one were new and which one were seen earlier. For the latter, they also performed a Remember-Know judgement. Data were analysed using SPM8, with an event design comparing modifications in cerebral activity between the two subjects groups during encoding (1) for the items leading to recollection during the recognition phase compared to those leading to familiarity, and (2) for the items associated with familiarity during the recognition phase compared to those which were not recognized. Results show that older adults display a heightened activity in the right middle frontal gyrus, medial cingulate and paracingulate left gyri as well as in the precuneus, bilaterally when they engage recollection processes. Amongst those regions, the precuneus seems to underlie compensatory processes, allowing the elderly to perform a richer encoding, as it was previously suggested for recollection processes during recall (c). However, no increase in activity was associated with familiarity processes in older adults, possibly because they are less demanding regarding attentional resources. (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Duverne, S., Motamedinia, S., & Rugg, M. D. (2009). The relationship between aging, performance, and the neural correlates of successful memory encoding. Cerebral Cortex, 19(3), 733-744. doi:10.1093/cercor/bhn122 (c) Angel, L., Bastin, C., Genon, S., Balteau, E., Phillips, C., Luxen, A., . . . Collette, F. (2013). Differential effects of aging on the neural correlates of recollection and familiarity. Cortex, 49(6), 1585-1597. doi:10.1016/j.cortex.2012.10.002 [less ▲]

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See detailL’influence normative de la Chine en Amérique latine, un défi stratégique pour l’Union européenne ?
Wintgens, Sophie ULg; Dabène, Olivier

Conference (2015, May 20)

La Chine est aujourd’hui devenue un partenaire commercial incontournable, un important pourvoyeur d’investissements directs étrangers et un grand fournisseur de prêts financiers pour un nombre croissant ... [more ▼]

La Chine est aujourd’hui devenue un partenaire commercial incontournable, un important pourvoyeur d’investissements directs étrangers et un grand fournisseur de prêts financiers pour un nombre croissant de pays d’Amérique latine. L’accroissement de ses échanges économiques et commerciaux avec ce sous-continent va de pair avec l’imposition des normes économiques et politiques dont sa politique commerciale internationale est porteuse. Cet article pose dès lors la question du défi que représente cette influence normative chinoise pour la stratégie déployée par l’Union européenne envers l’Amérique latine. [less ▲]

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

Conference (2015, May 20)

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

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

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

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

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

Conference (2015, May 20)

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

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

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See detailChanges of macrofauna stable isotope compositions in a very inconstant seagrass detritic habitat: actual diet modification or baseline shift?
Remy, François ULg; Mascart, Thibaud ULg; Dauby, Patrick ULg et al

Conference (2015, May 20)

Decayed leaves of the Neptune grass Posidonia oceanica, detached and then exported during storms, constitute an important compartment in terms of organic matter transfer from the seagrass bed to the other ... [more ▼]

Decayed leaves of the Neptune grass Posidonia oceanica, detached and then exported during storms, constitute an important compartment in terms of organic matter transfer from the seagrass bed to the other habitats, particularly coastal habitats. These exported litter accumulations (ELA) support a diverse (more than 130 species) and abundant (up to 4900 id.m-2) vagile macrofauna (invertebrates > 500µm) assemblage which may play a key role in the degradation, enrichment and carbon transfer from P. oceanica dead material to coastal food chains. Indeed, preliminary results of vagile invertebrates gut content observations show that even if only a few of these species ingest a large proportion of P.oceanica dead leaves fragments, most of the others ingest a small but non-negligible part, suggesting a potential role of the whole community in the mechanical fragmentation of the dead leaves. ELA are very dynamic habitats with highly variable food availability, quality, and composition. Such an inconstant habitat may result in drastic modifications of the invertebrate community but also of its trophic structure and ecology. To test this hypothesis of influence of pulsed availability, quality and composition of food sources on the vagile macrofauna diet, we took seasonal samples in Calvi Bay (Corsica, 8°45’E; 42°35’N), at two sites between August 2011 and May 2012. Stable isotopes analysis (C&N) were conducted at an individual level on dominant macrofauna species and mixing and isotopic niche model packages in R were used. Bayesian inference “SIBER” package highlighted significant seasonal and spatial differences of diet at the community, specific and even intraspecific level. Data confirm the potential transfer of seagrass material to animal tissues but in various proportions depending of the species and the season. But one question remained: are these variations reflection a true diet change, or only a spatiotemporal baseline variation of the food sources isotopic composition? “SIAR” Bayesian mixing model showed that it depends on the species and that the two responses co-occur. We emphasized the need to work at the specific level but also with an adequate temporal resolution for sampling to encompass diet and baseline variability. [less ▲]

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See detailStructural properties of densified GexSe1-x glasses
Yildirim, Can ULg; Micoulaut, Matthieu; Raty, Jean-Yves ULg

Conference (2015, May 20)

The evolution in structural properties of liquid and densified glassy GexSe1-x is investigated by use of First Principles Molecular Dynamics (FPMD) combined with X-ray absorption (XAS) experiments for the ... [more ▼]

The evolution in structural properties of liquid and densified glassy GexSe1-x is investigated by use of First Principles Molecular Dynamics (FPMD) combined with X-ray absorption (XAS) experiments for the glassy state. Four different compositions (x=10%, 16%, 18% and 33%) representing the flexible and stressed rigid sides of the reversibility window are the focus of the study. The target systems were studied at pressures up to ~ 11 GPa under both annealed and cold compression conditions. We examine the structure factors, pair distribution functions, bond angle distributions, coordination numbers and neighbor distributions. The results show that the real and reciprocal space properties are in very good agreement with the experimental findings. The structural evolution during densification reveals the edge sharing tetrahedra is maintained upon compression whereas Ge-Ge homopolar bonds tend to increase in number. Ge-Se-Ge bond angular distributions show a transformation from tetrahedral octahedral geometry. We discuss the effect of thermal history on structural properties during densification. [less ▲]

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

Conference (2015, May 20)

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See detailSimulations numériques sur des solides plongés, dans un contexte X-FEM
Duboeuf, Frédéric ULg; Béchet, Eric ULg

Conference (2015, May 20)

Ce travail traite des différents enjeux pour conserver toutes les capacités des calculs par éléments finis, en s’affranchissant des maillages conformes à la géométrie. La représentation de la géométrie ... [more ▼]

Ce travail traite des différents enjeux pour conserver toutes les capacités des calculs par éléments finis, en s’affranchissant des maillages conformes à la géométrie. La représentation de la géométrie, la construction d’un espace fonctionnel adapté et l’imposition des conditions aux limites sont abordées dans le contexte de la méthode des éléments finis étendus, tout particulièrement en présence de solides plongés dans un espace de dimension supérieure. L’approche proposée permet de traiter tout type de plongement, c.-à-d. des problèmes 1, 2, et/ou 3D plongés dans des maillages 2 ou 3D. [less ▲]

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See detailQuelles stratégies africaines face aux émergents?
Mputu Ingole, Jean-Claude ULg

Conference (2015, May 20)

Le rapprochement entre l’Afrique et les pays émergents pose toute une série des questions. Dans cet article, nous voulons nous interroger sur la position africaine face à ces nouveaux acteurs. Le ... [more ▼]

Le rapprochement entre l’Afrique et les pays émergents pose toute une série des questions. Dans cet article, nous voulons nous interroger sur la position africaine face à ces nouveaux acteurs. Le continent africain est-il un acteur conscient des enjeux en cours avec ces nouveaux « partenaires », pour reprendre les termes de l’Union Africaine, ou comme le suggère certains auteurs, elle serait entrain de subir une fois de plus la volonté des acteurs extérieurs ? Car si l’on constate que l’ensemble des pays émergents ont mis en place des nouvelles stratégies africaines, le contraire ne paraît pas évident. Ce papier se propose donc de voir s’il existe une ou plusieurs stratégies africaines vis-à-vis des émergents et si oui, de les analyser dans le contexte d’un monde en pleine mutation avec des nouveaux enjeux. Comment l’Union Africaine fait face aux nouvelles sollicitations des Etats émergents ? Compte-t-elle en tirer profit pour sa propre affirmation comme une actrice qui compte ou bien est-elle marginalisée par les Etats africains qui chacun, en ce qui le concerne, recherche ses propres intérêts. A-t-elle mis en place des nouveaux instruments pour gérer, selon ses intérêts cet accroissement de coopération avec les pays émergents. Quels rôles jouent les organisations régionales et/ou le NEPAD dans le développement de ces nouvelles coopérations ? Car au moment où la croissance africaine est l’une des plus fortes au monde et que le nombre de ses partenaires ne cesse d’augmenter, il est dès lors question de savoir comment l’Afrique se prépare à saisir ces nouvelles opportunités pour renforcer sa présence sur le monde avec ou sans les émergents. [less ▲]

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

Conference (2015, May 19)

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

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

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

Poster (2015, May 19)

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

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

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See detailFrom the Hubble Space Telescope to Juno, unraveling the secrets of Jupiter's UV aurorae
Bonfond, Bertrand ULg

Conference (2015, May 19)

The successive generations of instruments on board the Hubble Space Telescope (HST) have revealed an increasing amount of details concerning the aurorae of Jupiter. Among the most striking results is the ... [more ▼]

The successive generations of instruments on board the Hubble Space Telescope (HST) have revealed an increasing amount of details concerning the aurorae of Jupiter. Among the most striking results is the finding that these aurorae are actually made of a multitude of components arising from a variety of processes, ranging from the local interaction of the Jovian moons with the magnetospheric plasma to solar-wind induced compression of the whole magnetosphere. In this presentation, I will review a few recent results obtained from Hubble Space Telescope observations. First, I will show how the morphology and the dynamics of the Ganymede footprint, i.e. the aurora on Jupiter created by the electromagnetic interaction between Ganymede and Jupiter, allowed us to infer the processes at play. Then, I will present results on the vertical profile of the auroral emissions and what they tell us about the acceleration of the electrons causing the auroral emissions. Furthermore, I will describe some of the short-timescale dynamics of the polar-most emissions, including their quasi-periodic nature. Finally, I will conclude with a short description of the expected outcome of the Juno mission, which will provide its first scientific results in fall 2016. [less ▲]

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Peer Reviewed
See detailDrift potential of tilted shielded rotary atomisers based on wind tunnel measurements
Ouled Taleb Salah, Sofiene ULg; Massinon, Mathieu ULg; De Cock, Nicolas ULg et al

in 67th International Symposium on Crop Protection (2015, May 19)

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

Poster (2015, May 19)

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

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

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

Conference (2015, May 19)

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

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

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

Conference (2015, May 19)

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

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

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See detailScreening for interesting elicitors to protect wheat against Zymoseptoria tritici
Le Mire, Géraldine ULg; Siah, Ali; Fauconnier, Marie-Laure ULg et al

Conference (2015, May 19)

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 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). In addition, the phytotoxicity and biocide activities of these products were 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 detailComputer simulations of spray retention by a 3D barley plant: effect of formulation surface tension
Massinon, Mathieu ULg; De Cock, Nicolas ULg; Ouled Taleb Salah, Sofiene ULg et al

in 67th International Symposium on Crop Protection (2015, May 19)

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See detailDrop size distribution measurement of ISO nozzles by shadowgraphy method
De Cock, Nicolas ULg; Massinon, Mathieu ULg; Ouled Taleb Salah, Sofiene ULg et al

in Drop size distribution measurement of ISO nozzles by shadowgraphy method (2015, May 19)

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See detailAssessment of the species richness of highly eusocial bees according with habitat in Gabon
Fabre Anguilet, Edgard ULg; Bengone Ndong, Toussaint; Nguyen, Bach Kim ULg et al

Poster (2015, May 18)

Bees are among the most e ective pollinators. These insects include honeybee and stin- gless bee. In Africa, habitat loss is the main threat to these insects. This loss of habitat is largely due to ... [more ▼]

Bees are among the most e ective pollinators. These insects include honeybee and stin- gless bee. In Africa, habitat loss is the main threat to these insects. This loss of habitat is largely due to various human activities. An evaluation of the richness of social bees in three locaties in Gabon (Central Africa) was conducted from October 2013 to March 2014: Kougouleu who underwent deforestation and implantation of food crops, forest area Mas- sengalini in bu er zone of protected area of Lope and Lekokodiba in logging concession of Preccious Woods Gabon. For this, a collection was conducted using yellow traps lled with a mixture of water and honey and using a hand vacuum in 20 sites in each area. The number of species was compared to that estimated there are about thirty years. Eleven species of social bees (Apis mellifera adansonii and ten stingless bee species) were collected, of which 5 to Kougouleu, 8 to Massengalini and 11 to L ekokodiba. Honeybee has been collected in all localities. Forest localities are distinguished from Kougouleu by higher species diversity. This di erence is highly signi cant (Kruskal-Wallis 2 = 45.362, df = 2 and p-value<0.001). A decrease of approximately 50% of the number of stingless bee species in 30 years was found to Kougouleu, while the number of social bee species varies little in forest localities. Our study shows that the loss of forest habitat causes a decline in the species richness of social bees and stingless bees are more sensitive to this loss as the honeybee. [less ▲]

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See detailQuestion Intégrative - Médecine - Module Système Nerveux
Pasquet, Coralie ULg; Van de Poël, Jean-François ULg; Schaffer, Patrick ULg et al

Poster (2015, May 18)

Au cours du premier quadrimestre de l’année académique 2014 - 2015, une nouvelle activité a été proposée aux 270 étudiants inscrits en 3ième année du grade de Bachelier en Médecine à l’Université de Liège ... [more ▼]

Au cours du premier quadrimestre de l’année académique 2014 - 2015, une nouvelle activité a été proposée aux 270 étudiants inscrits en 3ième année du grade de Bachelier en Médecine à l’Université de Liège. Cette activité a été réalisée dans le cadre du « Module Système Nerveux ». [less ▲]

Detailed reference viewed: 27 (6 ULg)
See detailAliphatic polyphosphates: a promising family of polymers for drug delivery
Vanslambrouck, Stéphanie ULg; Clément, Benoit; Riva, Raphaël ULg et al

Poster (2015, May 18)

Thanks to their biocompatibility and biodegradability, polyphosphates are appealing polymers for biomedical applications. In contrast to polyesters, polyphosphate properties and functionality are easily ... [more ▼]

Thanks to their biocompatibility and biodegradability, polyphosphates are appealing polymers for biomedical applications. In contrast to polyesters, polyphosphate properties and functionality are easily tuned via the chemical nature of the lateral chains. In this work, a series of amphiphilic PEO-block-polyphosphate copolymers were synthesized by organo-catalyzed ring-opening polymerization of cyclic phosphates. These polymers are directly dissolved in water in the absence of any organic solvent and they self-assemble to form nanoparticles Our work aims at changing the lateral chain of polyphosphates to investigate the influence of this structural modification on (i) the size of the nanoparticles, (ii) the critical aggregation concentration, (iii) the encapsulation of an hydrophobic drug in the core of the nanoparticles and, finally, (iv) the release of the drug. [less ▲]

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See detailDémocratie et populisme: quelle réalité pour quelle légitimité?
Biard, Benjamin; Debras, François ULg

Conference (2015, May 18)

Detailed reference viewed: 22 (12 ULg)
See detailNon-isocyanate polyurethane: from the monomer synthesis to foamed materials
Gennen, Sandro ULg; Alves, Margot ULg; Tassaing, Thierry et al

Poster (2015, May 18)

Polyurethane (PU) is one of the most important polymers in our everyday life with numerous applications such as thermosets, thermoplastics, elastomers, adhesives, sealants, coatings, rigid and flexible ... [more ▼]

Polyurethane (PU) is one of the most important polymers in our everyday life with numerous applications such as thermosets, thermoplastics, elastomers, adhesives, sealants, coatings, rigid and flexible foams... Classically, PUs are produced by a step-growth polymerization between diols and diisocyanates. However, isocyanates are harmful upon prolonged exposure to vapours which can lead to health issues such as asthma and skin irritation. In addition, isocyanates are produced from even more toxic and explosive phosgene. Due to these problems in combination with increasing regulatory scrutiny, there is today a need to develop isocyanate- and phosgene free- PU synthesis, also called non-isocyanate polyurethane or NIPUs. One of the most promising alternatives to the conventional synthesis of PU relies on the step-growth polymerization between bicyclic carbonate monomers and diamines, but until now, obtaining high molar mass NIPUs in a short time still remains a challenge. This study will be focused on three objectives: 1) The synthesis of CO2-sourced biscyclic carbonates by CO2/epoxide coupling using new highly efficient bicomponent organocatalysts allowing the fast conversion of epoxides into the corresponding cyclic carbonates under mild and solvent-free conditions. 2) The synthesis of high molar mass NIPUs from CO2-sourced monomers and diamines thanks to the use of efficient organocatalysts. A series of organic compounds interacting with cyclic carbonates by hydrogen bonding were first identified and their catalytic activity was highlighted by a model reaction between ethylene carbonate and a primary amine before extrapolation to NIPU synthesis. 3) The scCO2-assisted foaming of CO2-sourced NIPUs with production of potential carbon zero-emission materials with low thermal conductivity [less ▲]

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See detailA tool for the precision synthesis of poly(ionic liquid)s in water
Cordella, Daniela ULg; Kermagoret, Anthony; Debuigne, Antoine ULg et al

Conference (2015, May 18)

In recent years, poly(ionic liquid)s (PIL)s were found to take an enabling role in important fields of polymer chemistry and material science. PILs combine the unique properties of ionic liquids with the ... [more ▼]

In recent years, poly(ionic liquid)s (PIL)s were found to take an enabling role in important fields of polymer chemistry and material science. PILs combine the unique properties of ionic liquids with the flexibility and properties of macromolecular architectures giving rise to a new family of functional polymers that opens new area of applications such as polymer electrolytes in electrochemical devices, powerful dispersants and stabilizers, absorbing membranes, precursors for carbon materials, porous polymers, etc. In this communication, we will report on the implementation of organometallic-mediated radical polymerization (OMRP) technique for the precision synthesis of unprecedented PILs (co)polymers. We will discuss how an organocobalt complex can efficiently control the growth of vinyl imidazolium chains and lead to PILs with predicted molar masses and low polydispersities under mild experimental conditions, which provide low temperatures (compared to the conventional radical polymerization techniques) and also the use of water as green polymerization medium. The huge potential of this system will be also highlighted by describing the one-pot synthesis of vinyl imidazolium-based block copolymers in heterogeneous conditions. This OMRP is unique for providing well-defined vinyl imidazolium based-copolymers opening for advanced PILs applications. [less ▲]

Detailed reference viewed: 28 (1 ULg)