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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 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 detailAn ALE meta-analysis on the neural correlates of personal goal processing during episodic future thoughts and mind-wandering
Stawarczyk, David ULg; D'Argembeau, Arnaud ULg

Conference (2015, May 28)

The ability to project oneself into the future is a multi-determined mental faculty that depends on various cognitive processes supported by an extended set of brain regions. The aim of the present study ... [more ▼]

The ability to project oneself into the future is a multi-determined mental faculty that depends on various cognitive processes supported by an extended set of brain regions. The aim of the present study was to examine a crucial component of future thinking—personal goal processing—and to determine its neural correlates during both experimentally directed mental time travel towards the future and mind-wandering, a form of spontaneous thoughts characterized by a prospective bias towards upcoming events. To address this question, we performed three distinct ALE meta-analyses of brain imaging studies on episodic future thinking, mind-wandering, and personal goal processing. We then examined the commonalities and differences in brain activity between these three areas of research. The results showed that the three domains activated a common set of brain regions within the default network including the posterior inferior parietal cortex, posterior cingulate cortex, lateral temporal lobe, and, most notably, the medial prefrontal cortex. Differences in activation were also observed, and the medial prefrontal cortex was more activated during personal goal processing than the other two domains. These findings suggest that the medial prefrontal cortex mediates the processing of personal goals during both episodic future thinking and mind-wandering. [less ▲]

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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 detailQuelle marge de manœuvre pour l'Amérique latine face à la concurrence stratégique entre la Chine et l’Union européenne?
Wintgens, Sophie ULg

Scientific conference (2015, May 28)

Cet article interroge la marge de manœuvre conférée à l’Amérique latine par la concurrence stratégique entre la Chine et l’Union européenne, devenues deux importants partenaires extrarégionaux d’un sous ... [more ▼]

Cet article interroge la marge de manœuvre conférée à l’Amérique latine par la concurrence stratégique entre la Chine et l’Union européenne, devenues deux importants partenaires extrarégionaux d’un sous-continent traditionnellement tourné vers les États-Unis. [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 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 detailLe donné phénoménal de Tim Crane
Gauvry, Charlotte ULg

Conference (2015, May 28)

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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 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)

Detailed reference viewed: 18 (1 ULg)
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See detailChitosan enriched three-dimensional matrix reduces inflammatory and catabolic mediators production by human chondrocytes
Oprenyeszk, Frédéric ULg; Sanchez, Christelle ULg; Dubuc, Jean-Emile et al

in PLoS ONE (2015), 10(5),

This in vitro study investigated the metabolism of human osteoarthritic (OA) chondrocytes encapsulated in a spherical matrix enriched of chitosan. Human OA chondrocytes were encapsulated and cultured for ... [more ▼]

This in vitro study investigated the metabolism of human osteoarthritic (OA) chondrocytes encapsulated in a spherical matrix enriched of chitosan. Human OA chondrocytes were encapsulated and cultured for 28 days either in chitosan-alginate beads or in alginate beads. The beads were formed by slowly passed dropwise either the chitosan 0.6%- alginate 1.2% or the alginate 1.2% solution through a syringe into a 102 mM CaCl2 solution. Beads were analyzed histologically after 28 days. Interleukin (IL)-6 and -8, prostaglandin (PG) E2, matrix metalloproteinases (MMPs), hyaluronan and aggrecan were quantified directly in the culture supernatant by specific ELISA and nitric oxide (NO) by using a colorimetric method based on the Griess reaction. Hematoxylin and eosin staining showed that chitosan was homogeneously distributed through the matrix and was in direct contact with chondrocytes. The production of IL-6, IL-8 and MMP-3 by chondrocytes significantly decreased in chitosan-alginate beads compared to alginate beads. PGE2 and NO decreased also significantly but only during the first three days of culture. Hyaluronan and aggrecan production tended to increase in chitosan-alginate beads after 28 days of culture. Chitosan-alginate beads reduced the production of inflammatory and catabolic mediators by OA chondrocytes and tended to stimulate the synthesis of cartilage matrix components. These particular effects indicate that chitosan-alginate beads are an interesting scaffold for chondrocytes encapsulation before transplantation to repair cartilage defects. [less ▲]

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See detailJA d'Alsace et WPJ, rencontre au sommet de la montagne...
Dalcq, Anne-Catherine ULg

Article for general public (2015)

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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 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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