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See detailStress analysis, damage tolerance assessment and shape optimisation without meshing
Hale, Jack UL; Bordas, Stéphane UL; Peng, Xuan et al

Poster (2014, June 24)

Detailed reference viewed: 103 (3 UL)
See detailROS-activated signaling network: dynamic modelling and design principles study
Kolodkin, Alexey UL; Ignatenko, Andrew UL; Sangar, Vineet et al

Poster (2014, June)

Detailed reference viewed: 159 (11 UL)
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See detailDifférence de genre en mathématiques chez les élèves de 3ème et 9ème année d’étude : Etude à grande échelle au Grand-Duché de Luxembourg
Gamo, Sylvie UL; Sonnleitner, Philipp UL; Hornung, Caroline UL et al

Poster (2014, June)

ÉpStan (Épreuves Standardisées) est une étude annuelle à grande échelle réalisée à Luxembourg depuis 2009. Les ÉpStan ont pour objectif d’évaluer le système éducatif luxembourgeois, en particulier le ... [more ▼]

ÉpStan (Épreuves Standardisées) est une étude annuelle à grande échelle réalisée à Luxembourg depuis 2009. Les ÉpStan ont pour objectif d’évaluer le système éducatif luxembourgeois, en particulier le niveau de compétences atteint en mathématiques des élèves de 3ème et de 9ème année d’étude (âgés en moyenne de 8 ans vs. 14 ans). A partir des résultats mathématiques ÉpStan 2013 du primaire et du secondaire, cette recherche vise d’une part, à examiner si l’écart de performance mathématique entre les sexes constaté par PISA 2012 chez les élèves de 15 ans luxembourgeois est confirmé chez les élèves de 14 ans et chez les élèves plus jeunes (8 ans), (Robinson, & Theule Lubienski, 2011) et d’autre part, à tester si les écarts de performance entre les sexes reflètent des différences de motivation et de confiance en soi et d’anxiété. [less ▲]

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See detailLes scores de compétences PISA sont prédictifs des résultats et carrières scolaires
Fischbach, Antoine UL; Keller, Ulrich UL; Preckel, Franzis et al

Poster (2014, June)

Detailed reference viewed: 47 (13 UL)
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See detailGenetic-algorithm based search strategy for optimal scenarios of future dual-pair gravity satellite missions
Iran Pour, Siavash; Reubelt, Tilo; Weigelt, Matthias UL et al

Poster (2014, June)

Detailed reference viewed: 107 (5 UL)
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See detailExploring Three Different Assessment Techniques of the Test for Creative Thinking-Drawing Production
Kirsch, Christiane UL; Lubart, Todd

Poster (2014, June)

L’aspect principal de la recherche présente consiste dans la comparaison de trois techniques d’évaluation du Test of Creative Thinking : Drawing Production (Test de Pensée Créative : Production Picturale ... [more ▼]

L’aspect principal de la recherche présente consiste dans la comparaison de trois techniques d’évaluation du Test of Creative Thinking : Drawing Production (Test de Pensée Créative : Production Picturale TPC-PP) (Urban & Jellen, 1995). Il s’agit de déterminer la technique d’évaluation la plus appropriée pour différents types de populations : architectes, psychologues et la population générale. L’échantillon des architectes compte 140 participants (65 femmes, 75 hommes, M = 21.96, ET = 4.37, distribution d’âge: 18-52 ans). L’échantillon des psychologues compte 121 participants (95 femmes, 24 hommes, M = 21.94, ET = 2.22, distribution d’âge: 19-32 ans). L’échantillon de la population générale compte 175 participants (109 femmes, 66 hommes, M = 24.47, ET = 3.52, distribution d’âge: 19-39 ans). Mis à part de la population des architectes, on retrouve des corrélations élevées entre les trois techniques d’évaluation. Ce résultat, quelque peu surprenant, est ramené au niveau d’expertise en dessin des architectes. Il semble bien que dans ce domaine spécifique, il est utile d’avoir recours à des juges experts en matière de dessin ou d’architecture. Des recherches futures pourraient tenter d’établir des modèles de prédiction de la créativité, adaptés aux champs plus vastes des arts, de la science et de la créativité dans la vie de tous les jours. Ils devraient être respectivement basés sur la méthode d’évaluation la plus adaptée à la population concernée. Ceci permettrait de fortifier la mesure du construit de la créativité et d’établir des modèles de prédiction de la créativité plus élaborés et plus spécifiques. [less ▲]

Detailed reference viewed: 66 (3 UL)
See detailDynamic modelling of ROS management and ROS-induced mitophagy
Kolodkin, Alexey UL; Ignatenko, Andrew UL; Sangar, Vineet et al

Poster (2014, June)

Detailed reference viewed: 141 (16 UL)
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See detailEffets d’un entraînement cognitif sur la marche chez les personnes âgées
Cornu, Véronique UL; Steinmetz, Jean-Paul; Federspiel, Carine

Poster (2014, May 16)

Plusieurs études ont pu démontrer l´association entre troubles de la marche, chutes et fonctions cognitives (attention, fonctions exécutives) chez les personnes âgées. Il semble ainsi prometteur dans le ... [more ▼]

Plusieurs études ont pu démontrer l´association entre troubles de la marche, chutes et fonctions cognitives (attention, fonctions exécutives) chez les personnes âgées. Il semble ainsi prometteur dans le cadre de la prévention de chutes, d´analyser les effets d´un entraînement cognitif sur la marche. En ce qui concerne les paramètres de la marche, une variabilité du pas élevée et un ralentissement de la vitesse de marche sous condition de double tâche, sont des indicateurs sensibles permettant d’évaluer le risque de chutes. La présente étude a analysé les effets d´un entraînement neurocognitif sur ces différents paramètres. L´échantillon est composé de 24 personnes âgées (âge moyen : 85, écart-type : 5.69). Les participants ont été affectés soit à un groupe d´intervention participant à un entraînement cognitif de six semaines (n=14), soit à un groupe contrôle (n=10). Un design quasi-expérimental avec des mesures pré- et posstest a été utilisé. L´analyse de la marche a été effectué à l´aide du système Gaitrite® qui permet de mesurer e.a. la vitesse, la variabilité de la durée du cycle de marche et la variabilité de la longueur du cycle de marche. Sous la condition double tâche, des effets d’importance clinique ont pu être observés dans le groupe d’intervention après l’entraînement cognitif. Une réduction de la vitesse de marche moins importante après l’entraînement (taille d’effet, δ = |.25|) ainsi qu’une réduction de la variabilité de la longueur du cycle de marche ont pu être observés (taille d’effet, δ = |.54|). Ces premiers résultats sont prometteurs et suggèrent qu´un entraînement cognitif peut avoir le potentiel d´améliorer les troubles de marche. Néanmoins, des recherches ultérieures avec des échantillons plus grands sont nécessaires afin de confirmer et de renforcer les résultats trouvés lors de l´étude présente. [less ▲]

Detailed reference viewed: 170 (10 UL)
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See detailCareer stages and work values: How work values influence career strategies?
Pignault, Anne UL; Meyers, Raymond UL; Bertrand, Clara et al

Poster (2014, May 01)

Detailed reference viewed: 117 (3 UL)
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See detailA model of guidance and counselling for young people with few qualifications
Houssemand, Claude UL; Meyers, Raymond UL; Tudela, Lluis et al

Poster (2014, May 01)

The aim of the European Leonardo da Vinci project Acrojump is to create a web-based E-profile for young people aged 16-25, who have few qualifications, no diploma and limited professional experience. All ... [more ▼]

The aim of the European Leonardo da Vinci project Acrojump is to create a web-based E-profile for young people aged 16-25, who have few qualifications, no diploma and limited professional experience. All relevant information about the past experience of these young people will be put online with the help of counsellors trained to elicit all pertinent facts that can be put into an electronic résumé (sports, participation in projects, field interventions, etc.). These details can represent different levels of competencies which may or may not tie to the professional domain. [less ▲]

Detailed reference viewed: 52 (1 UL)
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See detailThe role of relative motion information during observational learning in sports
Ghorbani, Saeed; Bund, Andreas UL

Poster (2014, May)

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See detailMarche et attention sélective chez les personnes âgées
Cornu, Véronique UL; Steinmetz, Jean-Paul; Federspiel, Carine

Poster (2014, May)

Un lien entre troubles de la marche, chutes et fonction cognitives (fonctions exécutives et attention), chez les personnes âgées peut être considéré comme établi. En ce qui concerne les paramètres de la ... [more ▼]

Un lien entre troubles de la marche, chutes et fonction cognitives (fonctions exécutives et attention), chez les personnes âgées peut être considéré comme établi. En ce qui concerne les paramètres de la marche, une variabilité du pas élevée et un ralentissement de la vitesse de marche sous condition de double tâche, sont des indicateurs sensibles permettant d’évaluer le risque de chute. La présente étude s´est intéressée aux différences de ces paramètres de marche en fonction de la performance dans un test d´attention sélective. L´échantillon est composé de 33 personnes âgées en long séjour (âge moyen : 83.7, écart-type : 6.2). L´analyse de la marche a été effectué à l´aide du système Gaitrite® qui permet de mesurer e.a. la vitesse, la variabilité de la durée du cycle de marche et la variabilité de la longueur du cycle de marche. L´attention sélective a été mesurée avec un test d´attention sélective adapté aux personnes âgées. Les personnes ont été regroupées sur la base de leur performance dans ce test (temps requis et erreurs commises) afin d´obtenir deux groupes : un groupe plus performant et un groupe moins performant. On a pu observer des différences de marche en fonction de l´attention sélective. Plus précisément, dans le groupe moins performant considérant les erreurs commises lors du test, la variabilité de la longueur du cycle de marche sous condition double tâche était sifnificativement supérieure à celle du groupe plus performant (U = 175.0, p < .05). Ces résultats mettent en évidence les différences dans les paramètres de marche, et le risque de chute associé, en fonction de la capacité d´attention sélective chez les personnes âgées. [less ▲]

Detailed reference viewed: 121 (11 UL)
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See detailCognitive style influences number-space associations
Georges, Carrie UL; Hoffmann, Danielle UL; Schiltz, Christine UL

Poster (2014, May)

Evidence for number-space associations comes from the spatial-numerical association of response-codes (SNARC) effect, consisting in faster reaction times to small/large digits with the left/right hand ... [more ▼]

Evidence for number-space associations comes from the spatial-numerical association of response-codes (SNARC) effect, consisting in faster reaction times to small/large digits with the left/right hand respectively. The cognitive processes underlying the SNARC effect are suggested to be task-dependent, such that number-space interactions result from verbal-spatial and visual-spatial number coding in parity and magnitude judgment tasks respectively (van Dijck et al., 2009). Moreover, the SNARC effect is characterized by high inter-individual variability (Hoffmann et al., 2014). Here we aimed to determine whether differences between the cognitive styles of individuals could influence the SNARC effect in a parity and magnitude judgment task. To distinguish between verbal and visual cognitive styles and between object- and spatial-visualizers, participants (n=74, 36 females, mean age=23.45 years) completed a modified version of Kirby et al.’s (1988) Verbalizer-Visualizer Questionnaire (VVQ, as in Mendelson & Thorson, 2004) and the Object-Spatial Imagery Questionnaire (OSIQ, Blajenkova et al., 2006, purchased from MM Virtual Design, LLC) respectively. Each item was placed on a five-point rating scale between strongly agree and strongly disagree, allowing us to compute verbal, visual, object and spatial scores for each participant. Participants that featured visual/verbal and spatial/object score ratios that were either both below or above the respective median ratio (visual/verbal ratio: M=1.09; spatial/object ratio: M=0.87) were classified as verbalizers (n=25, 16 females) and spatial-visualizers (n=25, 10 females) respectively. Participants subsequently performed the classical parity and magnitude judgment tasks. In verbalizers, the SNARC effect was significantly negative in the parity (slope=-11.2, p=0.001), but not the magnitude judgment task (slope=-1.2, p=0.53). Their verbal cognitive style might thus have induced a strong number-space association in tasks that supposedly draw on these cognitive processes, while it prevented spatial-numerical interactions in tasks that activate visuo-spatial number coding. Conversely, spatial-visualizers featured a significantly negative magnitude SNARC effect (slope=-4.8, p=0.04), indicating that a visuo-spatial style is not only necessary but sufficient to generate a number-space association in tasks that favour visuo-spatial number coding. Interestingly, they also manifested a significantly negative parity SNARC effect (slope=-9.9, p<0.001). It is likely that the spatial-visualizers switched strategy for the parity judgment task and - despite their visuo-spatial preferences - adopted the better-suited verbal strategy. Indeed, in contrast to verbalizers, their parity and magnitude SNARC effects did not correlate (spatial-visualizers: r=0.14, p=0.5; verbalizers: r=0.4, p=0.05). All in all, differences in cognitive styles might provide an additional explanation for the high inter-individual variability of the SNARC effect. Moreover, we provided further evidence for the verbal-spatial and visuo-spatial nature of the parity and magnitude SNARC effects respectively. [less ▲]

Detailed reference viewed: 155 (17 UL)
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See detailThe influence of emotional instability on daily pain outcomes in chronic pain patients
Van Ryckeghem, Dimitri; Rost, Silke UL; Vögele, Claus UL et al

Poster (2014, May)

Detailed reference viewed: 53 (1 UL)
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See detailRapport au savoir et support éducatif: La valeur du vrai dans la littérature enfantine
Dujardin, Céline UL; Lahaye, Willy

Poster (2014, May)

Chaque éducation est balisée de valeurs (Reboul, 2005). La famille élève l’enfant et l’entoure de valeurs d’affection. L’école transmet des valeurs liées au raisonnement et au sens de l’effort. La vie ... [more ▼]

Chaque éducation est balisée de valeurs (Reboul, 2005). La famille élève l’enfant et l’entoure de valeurs d’affection. L’école transmet des valeurs liées au raisonnement et au sens de l’effort. La vie professionnelle apprend un métier. L’échange crée des tensions, provoque des confrontations idéologiques et forme l’identité. Le concept complexe de l’éducation des valeurs s’exprime à travers la littérature enfantine, créée par des adultes pour transmettre à l’enfant des conceptions jugées importantes (Schmitz, 1997). La littérature enfantine transmet une conception psychosociale à l’enfant, celle-ci s’inscrivant dans un environnement ayant ses valeurs et ses références (Prince, 2009). La littérature enfantine représente ainsi un support de transmission éducative (Schneider, 2005). Sous forme de poster, la communication résume une étude qualitative menée sur la transmission de la valeur du vrai dans la littérature enfantine. Le vrai est la valeur relative à la vérité qui s’exprime dans la recherche des connaissances. La quête de cette valeur est mise en œuvre par le questionnement sur nos convictions et idéologies qui forgent notre vérité (Pourtois & Desmet, 2002). En effet, dans la littérature enfantine, le « vrai » est essentiellement défini par les concepts de la vérité dans les relations interpersonnelles et le rapport de l’homme au savoir. Concernant la transmission du message, le support éducatif du livre enfantin propose le questionnement direct et explicite du message. Les livres se centrent sur le jeune lecteur et suscitent sa réflexion en proposant plusieurs manières d’aborder la valeur du vrai. De cette manière, la littérature enfantine se présente comme un outil d’appropriation active du discours. Le poster présente une partie du travail de fin d’études, sous la direction de Prof. Willy Lahaye, défendu par Céline Dujardin en vue de l’obtention du diplôme de Master en Sciences de l’éducation à l’Université de Mons. Dans l’année académique 2009-2010, le travail de fin d’études a été rédigé sous l’intitulé « L’éducation des valeurs en album pour enfants. Une voie pour transmettre le patrimoine culturel dans la société actuelle ». Le travail de master utilise la méthode qualitative d’analyse structurale pour examiner le contenu des livres pour enfants. Pour définir la valeur du vrai dans la littérature enfantine, trois mises en opposition peuvent être retenues, à savoir la vérité versus le mensonge, le savoir s’opposant à la méconnaissance et le savoir dit « scientifique » se distinguant du savoir dit « commun ». La littérature enfantine offre un rapport au savoir varié et constitue ainsi un support éducatif diversifié. L’utilisation éducative de l’album pour enfants dépend du parent, de l’enseignant ou de tout autre éducateur. En termes d’accrochage scolaire, le support éducatif du livre enfantin philosophique s’accorde avec des approches pédagogiques culturelles et multiréférentielles proposant plusieurs identifications à l’enfant et acceptant plusieurs vérités pour construire le savoir. Ce cadre d’apprentissage s’avère favorable à la reconnaissance du raisonnement de l’enfant et donc également à son accrochage scolaire. [less ▲]

Detailed reference viewed: 102 (11 UL)
See detailEffects of Autistic Traits on Emotion Regulation in Neurotypical Adults
Pinto Costa, Andreia UL; Steffgen, Georges UL

Poster (2014, May)

Background: Individuals with Autism Spectrum Disorder (ASD) seem to have lower emotion regulation competence (Samson, Huber, & Gross, 2012). It has been reported that ASD is a continuum of social ... [more ▼]

Background: Individuals with Autism Spectrum Disorder (ASD) seem to have lower emotion regulation competence (Samson, Huber, & Gross, 2012). It has been reported that ASD is a continuum of social-communication disability (Baron-Cohen, Wheelwright, Skinner, Martin, & Clubley, 2001) and that neurotypical individuals are also part of that continuum and have autistic traits. Therefore, neurotypical individuals with more autistic traits would be expected to have lower emotion regulation competence than those with less autistic traits. Additionally, low levels of resting heart rate variability (HRV) have been associated with poor social functioning and emotional rigidity (Butler, Wilhelm, & Gross, 2006), which characterize ASD. Consequently, it is hypothesized that neurotypical individuals with more autistic traits should also have lower resting HRV. Objectives: To analyse if neurotypical adults with more autistic traits use less efficient emotion regulation strategies and the relation to cardiac vagal control. Methods: 80 undergraduate students participated in the study. None of the participants had a diagnosis of ASD. Participants were requested to answer four questionnaires: the Autism-Spectrum Quotient (AQ; Baron-Cohen et al., 2001), which comprises 50 items and assesses 5 autistic traits in the general population; the Difficulties in Emotion Regulation Scale (DERS; Gratz & Roemer, 2004), which comprises 36 items and assesses 6 factors of emotional dysregulation; the Emotion Regulation Questionnaire (ERQ; Gross & John, 2003), which comprises 10 items and assesses 2 emotion regulation strategies, cognitive reappraisal and expressive suppression; and finally, the 20-item Toronto Alexithymia Scale (TAS-20; Bagby, Parker, & Taylor, 1994), which comprises 20 items and assesses 3 factors of alexithymia. In the end, participants’ HRV was measured for 5 minutes. Results: Data collection is still being carried out and therefore definite results cannot be drawn. However, preliminary results seem to indicate that participants who have more autistic traits have in general more difficulties regulating their emotions. They use more often suppression than reappraisal as emotion regulation strategy and demonstrate more difficulties in two factors of the DERS (“Lack of emotional awareness” and “Lack of emotional clarity”). Results also seem to indicate that those with more autistic traits have a higher score in alexithymia. Concerning HRV, preliminary results indicate that those with more autistic traits have higher resting HRV. Conclusions: Preliminary results indicate that, neurotypical individuals who have more autistic traits have a less adaptive emotion regulation profile compared to neurotypical individuals with less autistic traits. They use more frequently expressive suppression and less frequently cognitive reappraisal and have more difficulties understanding and being aware of their emotions. This could be explained by the fact that, similarly to individuals with ASD, neurotypical individuals with more autistic traits have more difficulties taking another person mental perspective. This is also supported by findings that those with more autistic traits have a higher score in alexithymia, showing that they have more difficulties identifying and describing emotions. The unexpected HRV result might be explained by differences in the pattern of physiological responding (Zahn, Rumsey, & Kammen, 1987). [less ▲]

Detailed reference viewed: 191 (15 UL)
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See detailCanonical finger numeral configurations are perceived holistically
Di Luca, Samuel UL; Pesenti, Mauro; Schiltz, Christine UL et al

Poster (2014, April 04)

Sooner or later human beings represent or see numerosities represented by hands. This handling of small numerosities by prototypical finger configurations has been the focus of many experiments ... [more ▼]

Sooner or later human beings represent or see numerosities represented by hands. This handling of small numerosities by prototypical finger configurations has been the focus of many experiments investigating the possibility that semantic representations of numbers are motor-rooted. Canonical finger configurations (i.e. the culturally determined way to express numerosity with fingers) are for instance recognized faster (Di Luca et al., 2006), and give direct access to number semantics (Di Luca et Pesenti, 2008). It is also known that these effects are not due to a visual facilitation of canonical configurations (Di Luca et Pesenti, 2010), but to a different inner representation (Di Luca, Lefèvre and Pesenti, 2010). However, a precise characterization of their visual processing is currently lacking. We addressed this shortcoming by using an eye-tracking method based on gaze-contingent stimulus presentation (Van Belle et al., 2010). While participants named numerosities expressed by canonical and non-canonical finger numeral configurations presented in upright or inverted orientations, we selectively impaired analytical or holistic visual perception by respectively masking (in real time) peripheral or focal vision. Our data confirm the results found in literature: canonical configurations are processed faster than non-canonical ones, upright configurations are processed faster than inverted ones and holistic perception is faster than analytical one. Most importantly, we also demonstrate that canonical configurations are impaired by the peripheral mask (i.e. holistic vision hindered) whereas non-canonical ones are impaired by the foveal mask (i.e. analytical vision hindered). These results confirm that the practice of finger numeral configurations modifies not only the way human beings process and represent numerosities but especially the way to visually perceive them. [less ▲]

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See detailSemi-empirical phonon calculations for graphene on different substrates
Pereira Coutada Miranda, Henrique UL; Molina-Sanchez, Alejandro UL; Wirtz, Ludger UL

Poster (2014, April 02)

We investigate the graphene-substrate interaction via changes in the phonon dispersion of graphene. Ab-initio calculations on these systems are of high computational cost due to the non-commensurability ... [more ▼]

We investigate the graphene-substrate interaction via changes in the phonon dispersion of graphene. Ab-initio calculations on these systems are of high computational cost due to the non-commensurability of the unit cells of graphene and the substrate. This leads to the formation of Moiré patterns with accordingly large supercell sizes. We use a semi-empirical force constant model for the calculation of phonons of graphene on different metallic and insulating substrates. The interaction of graphene with the substrate is described via suitably chosen spring constants. The phonon dispersion in the primitive unit cell of graphene is obtained via an “unfolding procedure” similar to the ones used for the discussion of ARPES (angular resolved photo-emission spectroscopy) of graphene on incommensurate substrates. [less ▲]

Detailed reference viewed: 113 (5 UL)
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See detailTask instructions determine the visuo-spatial and verbal-spatial nature of number-space associations
Georges, Carrie UL; Schiltz, Christine UL; Hoffmann, Danielle UL

Poster (2014, April)

Evidence for number-space associations comes from the spatial-numerical association of response-codes (SNARC) effect, consisting in faster reaction times (RTs) to small/large digits with the left/right ... [more ▼]

Evidence for number-space associations comes from the spatial-numerical association of response-codes (SNARC) effect, consisting in faster reaction times (RTs) to small/large digits with the left/right hand respectively. Classically, they are thought to result from numerical coding along a left-to-right-oriented mental number line (visuo-spatial account; Dehaene et al., 1993). Recently, an association between the verbal concepts “small”/“left” and “large”/“right” has been suggested as an alternative explanation (verbal-spatial account; Gevers et al., 2010). Since the predominance of these accounts remains debated, we aimed to determine whether task instructions influence their extent of explaining the SNARC effect. A magnitude comparison task where the verbal labels “left”/“right” were displayed on the left/right response side alternatively allowed us to directly contrast the two accounts by comparing verbal SNARC slopes (based on differences in RTs to the labels “left” and “right”) with classical spatial SNARC slopes (based on differences in RTs to the left and right response side). In the verbal condition, participants (41 students, 20 female, mean age=21.6) responded to the assigned labels irrespective of their side of appearance, whereas the spatial condition required responding to the left or right response side irrespective of the displayed label. Under verbal instructions, only the verbal slope was significantly negative (verbal slope=-67.54, spatial slope=-4.82). Conversely, no significant difference was observed between verbal and spatial slopes under spatial instructions – both slopes being significantly negative (verbal slope=-15.12, spatial slope=-29.39). Taken together, number-space associations arise from verbal coding regardless of task instructions, while spatial coding only occurs under spatial instructions. [less ▲]

Detailed reference viewed: 94 (21 UL)
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See detailThe effect of languages on the production and recognition of numbers in German-French bilinguals
Van Rinsveld, Amandine UL; Schiltz, Christine UL; Ugen, Sonja UL

Poster (2014, April)

How do bilinguals produce and recognize two-digit number words? We investigated this question at different language proficiency levels in German-French bilinguals. German two-digit number words indeed ... [more ▼]

How do bilinguals produce and recognize two-digit number words? We investigated this question at different language proficiency levels in German-French bilinguals. German two-digit number words indeed follow the unit-decade order, whereas in French the order is decade-unit. Our study was conducted in Luxembourg where pupils learn both languages at primary school. Moreover mathematics are taught in German at primary school but in French at secondary school. Pupils from grades 5 (primary school), 8 (beginning of secondary school) and 11 (middle of secondary school) performed two numerical tasks: In the number recognition task, participants were presented a spoken number word that they had to recognize among four visually presented Arabic numbers. In the number production task, participants had to pronounce visually presented Arabic numbers. Both tasks were performed in German and in French and we compared language-related performance differences for the 3 levels of language proficiencies. Participants of all levels recognized and produced number-words more efficiently in their dominant language (i.e. German). However, this advantage for the dominant language was especially prominent at the lowest level of language proficiency when mathematics education was implemented in the dominant language (i.e. German). Furthermore, performance levels decreased with increasing number size, but over and above this general trend, participants of all proficiency levels showed specific difficulties with the complex structure of French number words over 60. Taken together, these results support the view that number and language processing are tightly associated, since language proficiency and language structure influence very simple and basic numerical tasks. [less ▲]

Detailed reference viewed: 106 (15 UL)
See detailField-induced spin helix chirality in nanocrystalline Ho
Szary, Philipp UL; Bick, Jens-Peter UL; Malyeyev, Artem et al

Poster (2014, April)

Detailed reference viewed: 48 (6 UL)
See detailDynamic change of host gastrointestinal microbiome and immune status in relation to mucosal barrier effects during chemotherapy and immune ablative intervention in humans
Kaysen, Anne UL; Heintz, Anna UL; Lebrun, Laura UL et al

Poster (2014, April)

The human gastrointestinal tract is colonized by communities of endogenous microbes, commonly referred to as the microbiome. Here, the microbiota are in close contact with the host intestinal mucosa and ... [more ▼]

The human gastrointestinal tract is colonized by communities of endogenous microbes, commonly referred to as the microbiome. Here, the microbiota are in close contact with the host intestinal mucosa and its innate and adaptive immune systems. The fact that certain stimuli induce an inflammatory response whereas others induce tolerance suggests, that the host immune system interacts with the microbiota and vice versa in different ways. However, the exact details of theses interactions remain largely unknown. It is known that cancer treatment can result in severe adverse effects like mucositis and in combination with allogeneic stem cell transplantation (Tx), in graft-versus host disease (GvHD). However, there is at present only sparse information available on the effects of chemotherapy on the intestinal microbiota and resulting changes in microbiome-immune system interactions. Almost no data exists on the effect of allogeneic stem cell Tx on the composition of the gastrointestinal microbiota. In this project, we are studying the complex interactions between the host and the intestinal microbiota after chemotherapy with or without allogeneic Tx and the occurrence of severe adverse side effects such as mucositis and GvHD. Using a systems biology approach including metagenomics and RNAseq, fecal samples and blood plasma samples from patients undergoing these treatments for malignancies will be analysed to identify the composition of the gastrointestinal microbiome and bacterial small RNAs. The main research hypothesis is that there are quantitative and qualitative changes in the gastrointestinal microbiome following chemotherapy and allogeneic Tx which are linked to the immune status of the patients and possible treatment side-effects, in particular mucositis and GvHD. We aim to provide knowledge on how the host's intestinal mucosa and immune system influence the gastrointestinal microbiome and on the role and involvement of the gastrointestinal microbiota in development in mucositis and GvHD. Importantly, this could help in the formulation of measures to prevent mucositis and GvHD development. [less ▲]

Detailed reference viewed: 267 (36 UL)
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See detailGender differences in mathematics achievement in 3rd and 9th grade students: A large-scale study in Luxembourg.
Gamo, Sylvie UL; Sonnleitner, Philipp UL; Hornung, Caroline UL et al

Poster (2014, March 30)

Since 2009, ÉpStan (Épreuves Standardisées) is an annual large-scale study in Luxembourg. It aims to evaluate Luxembourg's school system, in particular students’ achieved competency level in mathematics ... [more ▼]

Since 2009, ÉpStan (Épreuves Standardisées) is an annual large-scale study in Luxembourg. It aims to evaluate Luxembourg's school system, in particular students’ achieved competency level in mathematics implemented in 3rd and 9th grade. The present study aims to investigate whether the existing gender gap in mathematics among 15-year-olds revealed by PISA 2012 can be confirmed in ÉpStan 9th grade and if it already exists in younger students’ mathematics performance (ÉpStan 3rd grade) (Robinson, & Theule Lubienski, 2011). Further, we study wether a gender gap in students’ drive, motivation and self-beliefs concerning mathematics performance exists. [less ▲]

Detailed reference viewed: 104 (9 UL)
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See detailAssimilation of zenith total delays in the AROME France convective scale model: a recent assessment
Mahfouf, Jean-François; Ahmed, Furqan UL; Moll, Patrick et al

Poster (2014, February)

Detailed reference viewed: 125 (6 UL)
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See detailA state machine for database non-functional testing
Meira, Jorge Augusto UL; Almeida, Eduardo; Le Traon, Yves UL

Poster (2014)

Over the last decade, large amounts of concurrent transactions have been generated from different sources, such as, Internet-based systems, mobile applications, smart- homes and cars. High-throughput ... [more ▼]

Over the last decade, large amounts of concurrent transactions have been generated from different sources, such as, Internet-based systems, mobile applications, smart- homes and cars. High-throughput transaction processing is becoming commonplace, however there is no testing technique for validating non functional aspects of DBMS under transaction flooding workloads. In this paper we propose a database state machine to represent the states of DBMS when processing concurrent trans- actions. The state transitions are forced by increasing concurrency of the testing workload. Preliminary results show the effectiveness of our approach to drive the system among different performance states and to find related defects. [less ▲]

Detailed reference viewed: 113 (2 UL)
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See detailSLAPn: A Tool for slicing Algebraic Petri nets
Khan, Yasir Imtiaz UL; Guelfi, Nicolas UL

Poster (2014)

Algebraic Petri nets is a well suited formalism to represent the behavior of concurrent and distributed systems by handling complex data. For the analysis of systems modelled in Algebraic Petri nets ... [more ▼]

Algebraic Petri nets is a well suited formalism to represent the behavior of concurrent and distributed systems by handling complex data. For the analysis of systems modelled in Algebraic Petri nets, model checking and testing are used commonly. Petri nets slicing is getting an attention recently to improve the analysis of systems modelled in Petri nets or Algebraic Petri nets. This work is oriented to define Algebraic Petri nets slicing and implement it in a verification tool. [less ▲]

Detailed reference viewed: 76 (11 UL)
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See detailThe development of number symbol processing: A fast periodic visual stimulation study
Mejias, Sandrine; Rossion, Bruno; Schiltz, Christine UL

Poster (2014)

In our cultures the meaning of number symbols is acquired and reinforced through education. Accordingly, it is critical to understand how children become experts in the use of Arabic numbers (AN). Here ... [more ▼]

In our cultures the meaning of number symbols is acquired and reinforced through education. Accordingly, it is critical to understand how children become experts in the use of Arabic numbers (AN). Here, we used fast periodic visual stimulation (FPVS) combined with a repetition-suppression paradigm (Rossion & Boremanse, 2011) to measure rapidly and objectively the sensitivity to symbolic numerical stimuli of 6-to-12-y.o. children (n=20) and adults (n=11). Participants were presented four sequences: two of AN and two of AN-like sham stimuli. Half of the sequences consisted of different stimuli (“10”, “18”, “12”,...), the other half of same stimuli (“10”) presented repeatedly. Stimuli appeared at 3.5 items/second (fundamental frequency=3.5 Hz), for 60 seconds. We observed a large increase of the EEG response at 3.5 Hz (a steady-state visual-evoked potential; Regan, 1966) over parieto-occipital electrodes. This response was larger during different than same sequences, especially when participants saw real (vs. sham) AN. The amplitude of this specific response to numbers increased with children’s age. Moreover its location changed from posterior occipital electrodes in childhood to more lateral parietal electrodes in adulthood. These results indicate that FPVS of AN is a promising tool to study the sensitivity to numerical magnitude in children and adults. [less ▲]

Detailed reference viewed: 90 (3 UL)
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See detailAn Arrow-like theorem over median algebras
Couceiro, Miguel; Teheux, Bruno UL

Poster (2014)

We present an Arrow-like theorem for aggregation functions over convervative median algebras. In doing so, we give a characterization of conservative median algebras by means of forbidden substructures ... [more ▼]

We present an Arrow-like theorem for aggregation functions over convervative median algebras. In doing so, we give a characterization of conservative median algebras by means of forbidden substructures and by providing their representation as chains. [less ▲]

Detailed reference viewed: 78 (6 UL)
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See detailDie Erstellung quantitativer Sozialindikatoren im transdiziplinären Diskurs: Empirische Fallanalyse der European Expertgroup on Youth Indicators
Decieux, Jean Philippe Pierre UL

Poster (2014)

In postindustriellen Gesellschaften und insbesondere im Zeitalter der Wissensgesellschaft greift die Politik zur gesamtgesellschaftlichen Steuerung v.a. in Krisensituationen immer häufiger auf externes ... [more ▼]

In postindustriellen Gesellschaften und insbesondere im Zeitalter der Wissensgesellschaft greift die Politik zur gesamtgesellschaftlichen Steuerung v.a. in Krisensituationen immer häufiger auf externes Expertenwissen zurück, um: • Alternativen abzuwägen, • Entscheidungen zu treffen, legitimieren, bewerten und • als Frühwarnsystem zu fungieren. Auf EU-politischer Ebene wird dieses Treffen von Entscheidungen auf Basis von fundiertem Wissen als „evidence-based-policy-making“ bezeichnet. Was die Organisation und Produktion von Wissen angeht, beschreiben zahlreiche Studien einen Wandel dieser Prozesse in den heutigen modernen Gesellschaften, auch im politikberatenden Kontext. Die Art der Wissensdiffusion und die Rollenaufteilung haben sich verändert. Die traditionell lineare Vorgehensweise wird zumeist durch hybride Kooperationsmodelle, in denen unterschiedliche transdisziplinäre Akteure (wie Wissenschaft, Politik und Praxis) Wissen ko-konstruieren/-produzieren, abgelöst. Studienschwerpunkt: Während die klassischen akademischen Routinen und Methoden der Wissensgenerierung soziologisch gut erforscht sind, besteht jedoch Forschungsbedarf zu der Art und Weise, wie Wissen in diesem transdisziplinären Diskurs generiert wird. Schwerpunkt dieser Studie ist die Wissensgenerierung über quantitative Sozialindikatoren. Sie sind eine Form externen Wissens, welches hervorgebracht wird, um politische Entscheider im Entscheidungsprozess zu entlasten und ihre Entscheidung zu legitimieren. Das zentrale Ziel dieser Studie ist, die Einflüsse des Wissensdiskurses auf die traditionell wissenschaftlichen Methoden der Sozialberichterstattung zu erforschen. In einer empirischen Fallanalyse wird die Arbeit der transnationalen und -disziplinären Expertengruppe European Expert Group on Youth Indicators mittels einer Mehrfachtriangulation rekonstruiert. Sie operationalisiert die Indikatoren des European Dashboard on Youth Indcators im Diskurs zwischen Politik, Praxis und Wissenschaft (disziplinäre Interessen) sowie nationalen und internationalen Interessen, Zielen und kulturellen Identitäten. [less ▲]

Detailed reference viewed: 88 (30 UL)
See detailTrabalho Escravo and the Globalized World
Harnoncourt, Julia UL

Poster (2014)

Detailed reference viewed: 8 (0 UL)
Peer Reviewed
See detailCanonical finger numeral configurations are perceived holistically
Di Luca, Samuel UL; Pesenti, Mauro; Schiltz, Christine UL et al

Poster (2014)

Sooner or later human beings represent or see numerosities represented by hands. This handling of small numerosities by prototypical finger configurations has been the focus of many experiments ... [more ▼]

Sooner or later human beings represent or see numerosities represented by hands. This handling of small numerosities by prototypical finger configurations has been the focus of many experiments investigating the possibility that semantic representations of numbers are motor-rooted. Canonical finger configurations (i.e. the culturally determined way to express numerosity with fingers) are for instance recognized faster (Di Luca et al., 2006), and give direct access to number semantics (Di Luca et Pesenti, 2008). It is also known that these effects are not due to a visual facilitation of canonical configurations (Di Luca et Pesenti, 2010), but to a different inner representation (Di Luca, Lefèvre and Pesenti, 2010). However, a precise characterization of their visual processing is currently lacking. We addressed this shortcoming by using an eye-tracking method based on gaze-contingent stimulus presentation (Van Belle et al., 2010). While participants named numerosities expressed by canonical and non-canonical finger numeral configurations presented in upright or inverted orientations, we selectively impaired analytical or holistic visual perception by respectively masking (in real time) peripheral or focal vision. Our data confirm the results found in literature: canonical configurations are processed faster than non-canonical ones, upright configurations are processed faster than inverted ones and holistic perception is faster than analytical one. Most importantly, we also demonstrate that canonical configurations are impaired by the peripheral mask (i.e. holistic vision hindered) whereas non-canonical ones are impaired by the foveal mask (i.e. analytical vision hindered). These results confirm that the practice of finger numeral configurations modifies not only the way human beings process and represent numerosities but especially the way to visually perceive them. [less ▲]

Detailed reference viewed: 61 (5 UL)
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See detailRecycle your stress! How the interpretation of acute stress influences blood pressure, cognitive performance and rumination
Schaan, Violetta UL; Walther, Eva

Poster (2014)

Reappraising arousal boosts efficient sympathetic activation and analytic performance. We investigated if mindful awareness of bodily changes without positive re-evaluation of this perception also helps ... [more ▼]

Reappraising arousal boosts efficient sympathetic activation and analytic performance. We investigated if mindful awareness of bodily changes without positive re-evaluation of this perception also helps to buffer against negative stress responses. Taken together the results suggest that both mindfulness and reappraisal influence stress-related blood pressure, working memory performance and rumination. [less ▲]

Detailed reference viewed: 170 (2 UL)
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See detailThe influence of body motion on random number generation
Sosson, Charlotte UL; Guillaume, Mathieu UL; Van Rinsveld, Amandine UL et al

Poster (2014)

Knowledge and thinking are constrained by sensory-motor processes. This increasingly influential view has been termed the “embodiment theory” and proposes that bodily actions directly impact the quality ... [more ▼]

Knowledge and thinking are constrained by sensory-motor processes. This increasingly influential view has been termed the “embodiment theory” and proposes that bodily actions directly impact the quality of mental representations. The present study specifically aimed to investigate the influence of passive whole-body movement on numerical cognition. Two recent studies (Loetscher, et al., 2008; Hartmann, et al. 2011) indeed indicate that head or body movements can induce a shift of the attention on the mental number line. More precisely, leftward movements seemed to enhance small number generation while rightward movements led to larger number generation. The current study investigated this effect by using a non-motorized rotating chair. Concretely, while seated, participants were cyclically rotated 40 times for a movement amplitude of 90° from left to right and vice versa at an average frequency of 0.3 Hz. During each 90° movement segment they had to randomly produce numbers ranging between 1 and 30, but for methodological reasons the six extreme numbers were excluded from the analysis. The results indicate that the average number produced during leftward movement was smaller than the average number produced during rightward movement. These findings confirm the impact of passive whole-body movement on the production of numerical stimuli, indicating that rotation-movements of the body can displace attention on the mental number line. [less ▲]

Detailed reference viewed: 95 (19 UL)
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See detailAddressing Technical Replicate Variance in Omics Data Analysis
Glaab, Enrico UL; Schneider, Reinhard UL

Poster (2014)

High-throughput omics datasets often contain technical replicates, included to account for technical sources of noise in the measurement process. Although summarizing these replicate measurements by using ... [more ▼]

High-throughput omics datasets often contain technical replicates, included to account for technical sources of noise in the measurement process. Although summarizing these replicate measurements by using robust averages may help to reduce the influence of noise on downstream data analysis, the information on the variance across the replicate measurements is lost in the averaging process and therefore typically disregarded in subsequent statistical analyses. We introduce RepExplore, a web-service dedicated to exploit the information captured in the technical replicate variance to provide more reliable and informative differential expression and abundance statistics for omics datasets. The software builds on previously published statistical methods, which have been applied successfully to biomedical omics data but are difficult to use without prior experience in programming or scripting. RepExplore facilitates the analysis by providing a fully automated data processing and interactive ranking tables, whisker plot, heat map and principal component analysis visualizations to interpret omics data and derived statistics. The web-based software is freely available at http://www.repexplore.tk. [less ▲]

Detailed reference viewed: 106 (7 UL)
See detailCommunity integrated omics links the dominance of a microbial generalist to fine-tuned resource usage
Muller, Emilie UL; Pinel, Nicolás; Laczny, Cedric Christian UL et al

Poster (2014)

Microbial communities are complex and dynamic systems that are influenced by stochastic-neutral processes but are mainly structured by resource availability and usage. High-resolution “meta-omics” offer ... [more ▼]

Microbial communities are complex and dynamic systems that are influenced by stochastic-neutral processes but are mainly structured by resource availability and usage. High-resolution “meta-omics” offer exciting prospects to investigate microbial populations in their native environment. In particular, integrated meta-omics, by allowing simultaneous resolution of fundamental niches (genomics) and realised niches (transcriptomics, proteomics and metabolomics), can resolve microbial lifestyles strategies (generalist versus specialist) in situ. We have recently developed the necessary wet- and dry-lab methodologies to carry out systematic molecular measurements of microbial consortia over space and time, and to integrate and analyse the resulting data at the population-level. We applied these methods to oleaginous mixed microbial communities located on the surface of anoxic biological wastewater treatment tanks to investigate how niche breadth (generalist versus specialist strategies) relates to community-level phenotypes and ecological success (i.e. population size). Coupled metabolomics and 16S rRNA gene-based deep sequencing demonstrate that the community-wide lipid accumulation phenotype is associated with the dominance of Candidatus Microthrix parvicella. By integrating population-level genomic reconstructions with transcriptomic and proteomic data, we found that the dominance of this microbial generalist population results from finely tuned resource usage and optimal foraging behaviour. Moreover, the fluctuating environmental conditions constrain the accumulation of variations, leading to a genetically homogeneous population likely due to fitness trade-offs. By integrating metagenomic, metatranscriptomic, metaproteomic and metabolomic information, we demonstrate that natural microbial population sizes and structures are intricately linked to resource usage and that differing microbial lifestyle strategies may explain the varying degrees of within-population genetic heterogeneity observed in metagenomic datasets. Elucidating the exact mechanism driving fitness trade-offs, e.g., antagonistic pleiotropy or others, will require additional integrated omic datasets to be generated from samples taken over space and time. Based on our observations, niche breadth and lifestyle strategies (generalists versus specialists) have to be considered as important factors for understanding the evolutionary processes governing microbial population sizes and structures in situ. [less ▲]

Detailed reference viewed: 149 (12 UL)
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See detailPerformance Evaluation of an IaaS Opportunistic Cloud Computing
Diaz, Cesar UL; Pecero, Johnatan UL; Bouvry, Pascal UL et al

Poster (2014)

This poster shows the performance evaluation of UnaCloud Opportunistic Computing IaaS. We analyze from an HPC perspective, two virtualization frameworks Virtual Box and VMware ESXi and compare them over ... [more ▼]

This poster shows the performance evaluation of UnaCloud Opportunistic Computing IaaS. We analyze from an HPC perspective, two virtualization frameworks Virtual Box and VMware ESXi and compare them over this particular opportunistic cloud environment. The benchmarks consist of two set of tests, High Performance Linpack and IOzone, that examine the performance and the Input/Output response. The purpose of the experiments is to evaluate the behavior of the different virtual environments over an opportunistic cloud environment and investigate how these are affected by different percentage of end-users. The results show a better performance for Virtual Box than VMware and the other way around for I/O response. Nevertheless, the experiments shows that VBox have more robustness than VMware. [less ▲]

Detailed reference viewed: 151 (5 UL)
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See detailBUT4Reuse Feature identifier: Identifying reusable features on software variants
Martinez, Jabier UL; Ziadi, Tewfik; Klein, Jacques UL et al

Poster (2014)

Detailed reference viewed: 156 (27 UL)
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See detailSelectivity of face perception to horizontal information over lifespan (from 6 to 74 year old)
Goffaux, Valerie; Poncin, Aude; Schiltz, Christine UL

Poster (2014)

Detailed reference viewed: 73 (1 UL)
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See detailPromoting Equality: Social Work and CRPD
Limbach-Reich, Arthur UL

Poster (2014)

Detailed reference viewed: 44 (1 UL)
See detailA 16S rRNA gene Illumina–based barcoded assay design for high throughput characterisation of microbial communities from anaerobic digesters
Calusinska, Magdalena; Goux, Xavier; Muller, Emilie UL et al

Poster (2014)

High throughput sequencing of 16S/18S rRNA gene is becoming an indispensable tool to explore microbial community ecology. To date, most of the studies using next generation amplicon sequencing of ... [more ▼]

High throughput sequencing of 16S/18S rRNA gene is becoming an indispensable tool to explore microbial community ecology. To date, most of the studies using next generation amplicon sequencing of microorganisms involved in the anaerobic digestion process (AD) are based on the 454 pyrosequencing. However, the cost per read obtained with the Illumina technology is currently less than 1/100 of that for the 454 pyrosequencing, thus enabling throughout sequencing and larger number of samples to be analysed per study (e.g. given the current Miseq output, around 100 000 reads per sample can be expected for a pool of 96 libraries). Moreover, the Illumina technology is less biased by the GC content of the template and currently allows for a relatively long sequence read of 600 bp (2 x 300bp). This consideration is particularly important, since longer sequences permit for more accurate assignment to a taxonomic group. Here, we designed and optimized an Illumina–based 16S rRNA amplicon approach for a high throughput characterization of microbial communities from different AD. [less ▲]

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See detail„To force or not to force. That is the question!“ – Die Auswirkungen des Einsatzes von Forced-Response-Fragen auf die Befragungsergebnisse –
Mergener, Alexandra; Sischka, Philipp UL; Decieux, Jean Philippe Pierre UL

Poster (2014)

Die Methode der Onlinebefragung hat sich innerhalb des letzten Jahrzehnts als Befragungsroutine etabliert. Sie ist zumeist mit niedrigen Kosten verbunden und ermöglicht es innerhalb kürzester Zeit hohe ... [more ▼]

Die Methode der Onlinebefragung hat sich innerhalb des letzten Jahrzehnts als Befragungsroutine etabliert. Sie ist zumeist mit niedrigen Kosten verbunden und ermöglicht es innerhalb kürzester Zeit hohe Fallzahlen zu erzielen sowie „fundierte“ Ergebnisse zu generieren. Dies führte einerseits zu einer Demokratisierung der Umfrageforschung, denn mithilfe der Onlinebefragung ist es nahezu jedem möglich ein Befragungsprojekt durchzuführen. Andererseits resultiert daraus aber auch, dass viele Befragungen von Laien durchgeführt werden, dadurch eine schlechte Qualität aufweisen und zahlreiche Operationalisierungsfehler enthalten (Jacob/Heinz/Décieux 2013; Schnell/Hill/Esser 2011). Ein Beispiel hierfür ist die Verwendung der Forced Response Option, deren Auswirkungen innerhalb dieses Forschungsprojektes untersucht werden. Theoretischer Hintergrund des Projektes Als Forced-Response wird allgemein die Möglichkeit bezeichnet den Respondenten einer Umfrage zur Beantwortung einer Frage zu verpflichten. Bei den meisten Programmpaketen zur Durchführung eines Onlinesurveys ist dies auf einfachste Art und Weise zu realisieren. Diese Praxis kommt zuweilen sehr häufig auch zur Anwendung, ohne dass sich die Fragesteller über eventuelle Folgen ihrer Wahl bewusst sind. In den Handbüchern der Programme (bspw. EFS Survey Manual 9.0) wird diese Option als eine Lösung angepriesen, die den Item Non Response verringert. In der Methodenliteratur gibt es jedoch zahlreiche Bedenken und Gegenstimmen für diese Vor-gehens¬weise (Kaczmirek 2005, Peytchev/Crawford 2005, Dillman/Smyth/Christian 2009, Schnell/ Hill/Esser 2011, Jacob/Heinz/Décieux 2013). Diese Bedenken speisen sich aus der Über¬legung, dass der Befragte plausible Gründe haben kann, um nicht zu antworten (der Befragte versteht die Frage nicht, die entsprechende Antwortkategorie fehlt, der Befragte will die Frage aus persönlichen Gründen bewusst nicht beantworten, usw.). Verpflichtet man den Befragten unter diesen Umständen eine Antwort zu geben, könnte dies möglicherweise dazu führen, dass die Befragung abgebrochen wird oder der Befragte eine willkürliche/inhaltsunabhängige Antwort gibt. Zusammenfassend lassen sich damit zwei zentrale Thesen aufstellen: 1. Forced-Response führt zu erhöhtem Unit Non Response. 2. Forced-Response führt zu weniger validen Antworten (Lügen oder Zufallsantwort). Allerdings gibt es bisher kaum empirische Untersuchungen, die diese Behauptungen belegen. Ziel des Projektes Über Split Ballot Experimente werden die genauen Folgen der Implementierung einer Forced-Response-Option empirisch abgebildet. Die Folgen sollen über die Analyse von Abbruchquoten und Antwortreaktionszeiten dargestellt werden. Die Feldphase des Online-Experiments endet Mitte Juli 2014, sodass wir dann in der Lage sind, aktuelle und bisher nicht veröffentlichte Ergebnisse auf dem Kongress zu präsentieren. [less ▲]

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See detailGradient Smoothing for Nearly Incompressible Hyperealsticity
Lee, Chang-Kye; Mihai, L. Angela; Kerfriden, Pierre et al

Poster (2014)

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See detailGradient Smoothing for Nearly Incompressible Hyperelasticity
Lee, Chang-Kye; Mihai, L. Angela; Kerfriden, Pierre et al

Poster (2014)

Detailed reference viewed: 81 (4 UL)
Peer Reviewed
See detailDiscrimination of Numerosities in children studied by means of Fast Periodic Visual Stimulation
Mejias, Sandrine; Rossion, Bruno; Schiltz, Christine UL

Poster (2014)

We are constantly dealing with quantities in our environment. This ability to process numerical magnitude is present in infants (Izard et al., 2009), a variety of animal species (Flombaum et al., 2005 ... [more ▼]

We are constantly dealing with quantities in our environment. This ability to process numerical magnitude is present in infants (Izard et al., 2009), a variety of animal species (Flombaum et al., 2005) and in tribes with small number words lexicon (Pica et al., 2004). It implies that our brain is able to extract the total number of items in a scene, regardless of perceptual interference (non-numerical properties of the stimuli). However, this ability seems to be refined through development (Halberda et al., 2012), due to visual-perception maturation and/or educational environment, e.g. when learning arithmetic. Here, we measured rapidly and objectively 6-to-12-y.o. children’s sensitivity to (non-)symbolic numerical stimuli (dots or Arabic numbers), using fast periodic visual stimulation (FVPS) as implemented in a repetition-suppression paradigm (Rossion & Boremanse, 2011). Children were presented with stimuli appearing at 3.5 items/second (fundamental frequency=3.5 Hz), for 60 seconds. Half of the sequences consisted of different stimuli at every cycle of stimulation (e.g., “10”, “18”, “12”,...), the other half of sequences were composed of same stimuli (“10”) repeated throughout the whole sequence. We observed a large increase of the EEG response at the fundamental frequency (a steady-state visual evoked potential; Regan, 1966) over the lateral parieto-occipital electrodes sites. This response was reduced when the same stimulus was repeated, especially for symbolic stimuli. These results are correlated to children’s age and visual-perception, arithmetic and non-symbolic numerical abilities (L-POST, KRT, Panamath). They indicate that FPVS of (non-)symbolic numerosities is a promising tool to study children’s sensitivity to numerical magnitude. [less ▲]

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See detailComparative Analysis of Real-Time Precise Point Positioning Zenith Total Delay Estimates
Ahmed, Furqan UL; Vaclavovic, Pavel; Teferle, Felix Norman UL et al

Poster (2013, December 13)

The use of observations from Global Navigation Satellite Systems (GNSS) in operational meteorology is increasing worldwide due to the continuous evolution of GNSS. The assimilation of near real-time (NRT ... [more ▼]

The use of observations from Global Navigation Satellite Systems (GNSS) in operational meteorology is increasing worldwide due to the continuous evolution of GNSS. The assimilation of near real-time (NRT) GNSS-derived zenith total delay (ZTD) estimates into local, regional and global scale numerical weather prediction (NWP) models is now in operation at a number of meteorological institutions. The development of NWP models with high update cycles for nowcasting and monitoring of extreme weather events in recent years, requires the estimation of ZTD with minimal latencies, i.e. from 5 to 10 minutes, while maintaining an adequate level of accuracy for these. The availability of real-time (RT) observations and products from the IGS RT service and associated analysis centers make it possible to compute precise point positioning (PPP) solutions in RT, which provide ZTD along with position estimates. This study presents a comparison of the RT ZTD estimates from three different PPP software packages (G-Nut/Tefnut, BNC2.7 and PPP-Wizard) to the state-of-the-art IGS Final Troposphere Product employing PPP in the Bernese GPS Software. Overall, the ZTD time series obtained by the software packages agree fairly well with the estimates following the variations of the other solutions, but showing various biases with the reference. After correction of these the RMS differences are at the order of 0.01 m. The application of PPP ambiguity resolution in one solution or the use of different RT product streams shows little impact on the ZTD estimates. [less ▲]

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See detailOn the capability to derive mass estimates from high-low satellite-to-satellite tracking data
Weigelt, Matthias UL; van Dam, Tonie UL; Tourian, M. J. et al

Poster (2013, December)

Recently it has been shown that it is possible to derive time-variable gravity signals from high-low satellite-to-satellite tracking (hl-SST) missions (Weigelt et al. 2013, JGR:Solid Earth, doi:10.1002 ... [more ▼]

Recently it has been shown that it is possible to derive time-variable gravity signals from high-low satellite-to-satellite tracking (hl-SST) missions (Weigelt et al. 2013, JGR:Solid Earth, doi:10.1002/jgrb.50283). Based on the GPS information only, we will present results derived from the dedicated gravity field missions CHAMP, GRACE and GOCE which allow us to determine mass estimates for various applications. Hydrologically induced mass changes on land cause the strongest mass variations in the gravity field and can be easily identified in the hl-SST data, especially in areas with strong signals such as the Amazon basin. Ice melt in Greenland can be derived from the data and mass estimates compare well to corresponding GRACE estimates. Also, loading time series based on these gravity field solutions agree well with GPS observations for various stations around the globe. We also discuss the limitations of the data, e.g. in detecting signals related to glacial isostatic adjustment or earthquake-induced gravity field changes. Overall, we will demonstrate that the quality of the GPS data is sufficient nowadays and with a proper processing strategy it is possible to derive reasonable mass estimates. As such, this type of observations may allow to bridge a possible gap between GRACE and its successor GRACE Follow-On scheduled for launch in 2017. [less ▲]

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See detailSocial Inequality and the transition to retirement in Europe and the US
Ponomarenko, Valentina UL

Poster (2013, November 28)

This study examines the transition to retirement in a comparative analysis. The intersection to retirement has been linked with diverse consequences in past research. On one side, studies find negative ... [more ▼]

This study examines the transition to retirement in a comparative analysis. The intersection to retirement has been linked with diverse consequences in past research. On one side, studies find negative effects on psychological well-being of retirement due to loss of employment, social networks and stability through work life. Others present results of a positive effect connected to pension. From a life course perspective, experiences in one’s employment history might impact the transition to and the retirement period itself. I hypothesize on the individual level that transition to retirement is influenced by working life experience and quality. The transition to retirement might be easier for people with a higher socio-economic status thus high education as well as financial resources. On the other hand, the experience of unemployment or lower job placement might cause depression or a decline of life satisfaction. The Theory of Cumulative Advantages and the mechanism of scarring propose that unemployment will have a long-life effect on the career. But is the effect even sustaining in old age? How does the transition to retirement influence life satisfaction and what impact has scarring? To answer these questions I will make use of SHARE and HRS longitudinal data on well-being of seniors and their socioeconomic situation and work history. The rich variation of countries in SHARE makes it possible to compare different welfare regimes. As SHARE lacks liberal countries, I will include the US to have a more consistent picture. [less ▲]

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See detailHydrokinetic and Solar Energy Contribution to a Reliable Energy Supply
Norta, David Peter Benjamin UL; Sachau, Jürgen UL; Allelein, Hans-Josef

Poster (2013, November 18)

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See detailAccelerating short transfers in 802.11 networks
Arcia-Moret, Andres; Montavont, Nicolas; Castignani, German UL

Poster (2013, November 14)

The legacy bandwidth discovery phase of TCP spends an unnecessary number of RTTs for reaching the fair share of the network. In this article we introduce a simple modification at the receiver that splits ... [more ▼]

The legacy bandwidth discovery phase of TCP spends an unnecessary number of RTTs for reaching the fair share of the network. In this article we introduce a simple modification at the receiver that splits the TCP ACKs in a controlled manner. This mechanism allows to fast ramp-up the TCP congestion window. Our experiments performed in a real testbed show benefits not only in the increased data throughput but also in a non-congested uplink (Acknowledgement) path in an 802.11 access. [less ▲]

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See detailGerman University-based Science: From Model to Contemporary Reality?
Dusdal, Jennifer UL

Poster (2013, November)

This QNRF-funded project features a cross-national investigation of the influence of higher education development and science capacity-building on scientific knowledge production. Measuring science on the ... [more ▼]

This QNRF-funded project features a cross-national investigation of the influence of higher education development and science capacity-building on scientific knowledge production. Measuring science on the basis of published papers in selected STEM disciplines, we identify factors behind national differences and global similarities. How does variation in national models and strategies to develop higher education and research universities explain long-term cross-national trajectories in science productivity over the 20th century? Observing unprecedented growth in scientific knowledge productivity, we selected six national cases that represent three phases of higher education development and science-based societies: a major European precursor model (Germany), American broad institutionalization of the currently dominant model, and, finally, Asian (Japan, China, Taiwan) and Middle Eastern (Qatar) innovators seeking to learn from the best. The enormous potential of a knowledge economy and society depends on continued production of scientific knowledge, but also its specification and enhanced quality. Even though scientists globally add to the world’s store of scientific knowledge, there are significant cross-national differences in relative contribution. While global production grows substantially, a few nations still produce the overwhelming majority of new science. For example, the U.S. leads the world in research, producing 21% of all research papers (2004-2008). Together with China (10%), UK (7%), Japan (6%) and Germany (6%), these five countries contribute 60% of all publications globally. Our preliminary research suggests that differences in key aspects of institutional models of higher education development and science capacity-building are associated with cross-national differences in scientific knowledge production over time. We use mixed-methods to analyze the institutional model of higher education development and science capacity-building in these nations over time. Our main measure is the number of published papers in journals, relying on a unique dataset from Thomson Reuters’ Web of Science (1900-2011). Examining trends in journal publications in selected STEM disciplines, we analyze how universities, investments in higher education and science, international collaborations, and scientific networks have changed to create the conditions for the “knowledge society”. Mainly, this poster presentation explains the influential German institutional model of the research university, which enjoyed preeminent status in modern science’s early institutionalization. Placing primacy on autonomous science and valorizing the unity of teaching and research, this type of university continues to dominate German higher education. Yet massive tertiary educational expansion, the rise of extra-university research institutes, and establishment of praxis-oriented universities of applied sciences challenge the foundational principle, threaten this globally popular model, and reduce university-based research capacity in Germany. Nevertheless, Germany’s dual pillars of mass universities and prestigious independent research institutes continue to boast one of the largest national scientific outputs globally. With an annual R&D investment of 2.84% GDP (2011), Germany has among the highest levels of science investment in Europe. Measured in publications, Germany still competes at the very top. While still a model for other countries, other top science countries today rely on their universities more in producing competitive science than does Germany. [less ▲]

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See detailLa construction métallique mixte un système allégé innovant
Schäfer, Markus UL

Poster (2013, November)

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See detailThe King Edward Point Geodetic Observatory in Support of Sea Level Research
Teferle, Felix Norman UL; Hunegnaw, Addisu UL; Ahmed, Furqan UL et al

Poster (2013, October 28)

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Geor- gia, South Atlantic Ocean, through a University of Luxembourg funded research project and in ... [more ▼]

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Geor- gia, South Atlantic Ocean, through a University of Luxembourg funded research project and in collaboration with the United Kingdom’s National Oceanography Centre, British Antarctic Survey and Unavco, Inc. Due to its remote location in the South Atlantic Ocean, as well as, being one of few subaerial exposures of the Scotia plate, South Georgia Island has been a key location for a number of global monitoring networks, e.g. seismic, geomagnetic and oceanic. However, no geodetic monitoring station has been established, e.g. by the International Global Navigation Satellite System (GNSS) Service (IGS) community, despite the lack of such observations from this region. In this study we give details of the establishment of the KEP Geodetic Observatory, i.e. the installation of the continuous GNSS station KEPA on Brown Mountain and the estab- lishment of a new height datum for the tide gauge through a network of benchmarks at the KEP research station. We will present an evaluation of the GNSS positioning results for the period from February to August 2013 and of the survey/levelling work carried out for the height reference. We will discuss the installation in terms of its potential contributions to sea level observations using tide gauges and satellite altimetry, studies of tectonics, glacio-isostatic adjustment and atmospheric processes. [less ▲]

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Peer Reviewed
See detailDay-to-day variability of emotions in chronic pain
Rost, Silke UL; Van Ryckeghem, Dimitri; Koval, Peter et al

Poster (2013, October 10)

Detailed reference viewed: 53 (6 UL)
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See detailRumination, interoceptive awareness and suggestibility predict the occurrence of the thermal grill illusion
Scheuren, Raymonde UL; Sütterlin, Stefan UL; Anton, Fernand UL

Poster (2013, October 10)

ruminationInterposed non-noxious cold and warm cutaneous stimuli applied via a thermal grill have repeatedly been shown to generate a paradoxical pain sensation, also described as ‘thermal grill illusion ... [more ▼]

ruminationInterposed non-noxious cold and warm cutaneous stimuli applied via a thermal grill have repeatedly been shown to generate a paradoxical pain sensation, also described as ‘thermal grill illusion of pain’. According to the ‘central disinhibition theory’ proposed by Craig and Bushnell [1], the pain phenomenon commonly qualified as burning can be explained by “an unmasking of cold-evoked activity of polymodal nociceptive lamina I spinothalamic neurons (activation by polymodal Cnociceptors) resulting from the reduction of normal coldevoked activity of thermoreceptive lamina I spinothalamic neurons (activation by Aδ cooling thermoreceptors) by spatial summation of the simultaneous warm stimuli in the thermoreceptive but not the nociceptive neurons.” Since a significant part of the tested subjects do however not display the thermal grill percept, it may be hypothesized that not only physiological-, but also psychological determinants play a crucial role in the generation of the paradoxical pain. Sad mood [2] and anxiety [3] have already been proposed as relevant psychological factors. The aim of the present research consisted in validating our custom made, water-driven and fMRI compatible thermal grill device [4], in identifying thermal grill ‘responders’ and ‘non-responders’ and in investigating whether different personality traits or states constitute predictors for the elicitation of the thermal grill illusion. [less ▲]

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See detailModular Hydrokinetic Micro Generation
Norta, David Peter Benjamin UL; Sachau, Jürgen UL; Allelein, Hans-Josef

Poster (2013, October 07)

Detailed reference viewed: 126 (14 UL)
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See detailEstimation abilities of large numerosities in preschool children
Mejias, Sandrine; Schiltz, Christine UL

Poster (2013, October)

The approximate number system (ANS) is thought to be a building block for the elaboration of formal mathematics. However, little is known about how this core system develops and if it can be influenced by ... [more ▼]

The approximate number system (ANS) is thought to be a building block for the elaboration of formal mathematics. However, little is known about how this core system develops and if it can be influenced by external factors at a young age (before the child enters formal numeracy education). The purpose of this study was to examine numerical magnitude representations of 5-6 year old children at 2 different moments of Kindergarten considering children's early number competence as well as schools' socio-economic index (SEI). This study investigated estimation abilities of large numerosities using symbolic and non-symbolic output formats (8-64). In addition, we assessed symbolic and non-symbolic early number competence (1-12) at the end of the 2nd (N = 42) and the 3rd (N = 32) Kindergarten grade. By letting children freely produce estimates we observed surprising estimation abilities at a very young age (from 5 year on) extending far beyond children's symbolic explicit knowledge. Moreover, the time of testing has an impact on the ANS accuracy since 3rd Kindergarteners were more precise in both estimation tasks. Additionally, children who presented better exact symbolic knowledge were also those with the most refined ANS. However, this was true only for 3rd Kindergarteners who were a few months from receiving math instructions. In a similar vein, higher SEI positively impacted only the oldest children's estimation abilities whereas it played a role for exact early number competences already in 2nd and 3rd graders. Our results support the view that approximate numerical representations are linked to exact number competence in young children before the start of formal math education and might thus serve as building blocks for mathematical knowledge. Since this core number system was also sensitive to external components such as the SEI this implies that it can most probably be targeted and refined through specific educational strategies from preschool on. [less ▲]

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See detailEmotion regulation in Autism Spectrum Disorder: A review
Pinto Costa, Andreia UL; Steffgen, Georges UL

Poster (2013, October)

Introduction: Emotion regulation is an important aspect of children emotional and social development. Especially, children with autism spectrum disorder (ASD) seem to be at a disadvantage regarding ... [more ▼]

Introduction: Emotion regulation is an important aspect of children emotional and social development. Especially, children with autism spectrum disorder (ASD) seem to be at a disadvantage regarding emotion regulation due to social interaction difficulties. In the present study we review the research findings on the specific emotion regulation strategies in children with ASD. Participants and Methods: We carried out literature searches using Primo Central ExLibris for all articles published on emotion regulation in children with ASD since 2003. Articles were included if they met the following criteria: a) comprised participants with ASD under the age of 18 years; b) contained empirical research findings on emotion regulation; and c) used a prospective group comparison design. At the end, the review includes 12 independent studies. Results: In general, findings indicate that children with ASD use less emotion regulation strategies than typically developing peers. However, some studies prove less efficient strategies in children with ASD, while others did not find differences. In studies analysing the impact of interventions, children show diminished expression of negativity and more appropriate emotion regulation during post-treatment. Conclusion: Emotion regulation difficulties are a serious concern for children with ASD, yet empirical studies on this topic are still scarce. More studies with larger samples are needed. Especially, other characteristics, such as social interaction and caregiver’s intervention, that might influence emotion regulation have to be further analysed. [less ▲]

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See detailDesign principles study of ROS management and ROS-induced mitophagy with a kinetic model
Kolodkin, Alexey UL; Ignatenko, Andrew UL; Sangar, Vineet et al

Poster (2013, September 27)

In vivo evidence demonstrates three fundamental interconnected adaptive survival mechanisms , which protect against excessive ROS that is generated during mitochondrial dysfunction: (i) autophagy ... [more ▼]

In vivo evidence demonstrates three fundamental interconnected adaptive survival mechanisms , which protect against excessive ROS that is generated during mitochondrial dysfunction: (i) autophagy/mitophagy, (ii) adaptive antioxidant response and (iii) NFkB signaling in cancer and neurodegeneration. We have been expanding a kinetic model which recapitulates the consensus understanding of the mechanisms responsible for cellular ROS – management system and performed modular analysis to analyze emergent behavior. We started with the simplest model and added stepwise new modules. We identify the qualitative role (certain emergent behavior) attributed to each module and thus understand the design principles of the system. We propose a detailed, mechanistic, kinetic model for studying how mutations relevant for diseases such as PD and cancer affect the emergent behavior of ROS management network. [less ▲]

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See detailA Bayesian Monte Carlo Markov Chain Method for the Statistical Analysis of Geodetic Time Series
Olivares Pulido, German UL; Teferle, Felix Norman UL

Poster (2013, September 06)

Geodetic time series provide information which help to constrain theoretical models of geophysical processes. It is well established that such time series, for example from GPS or gravity measurements ... [more ▼]

Geodetic time series provide information which help to constrain theoretical models of geophysical processes. It is well established that such time series, for example from GPS or gravity measurements, contain time-correlated noise which is usually assumed to be a combination of a long-term stochastic process (characterized by a power-law spectrum) and random noise. Therefore, when fitting a model to geodetic time series it is essential to also estimate the stochastic parameters beside the deterministic ones. In many cases the stochastic parameters have included the power amplitudes of both time-correlated and random noise as well as the spectral index of the power-law process. To date the most widely used method for obtaining these model parameter estimates is based on maximum likelihood estimation (MLE). We present a new Bayesian Monte Carlo Markov Chain (MCMC) method to estimate the deterministic and stochastic model parameters of geodetic time series. This method provides a sample of the likelihood function and thereby, using Monte Carlo integration, all parameters and their uncertainties are estimated simultaneously. One advantage of this method over MLE is that the computation time required increases linearly with the number of parameters, hence being very suitable for dealing with a large number of parameters. Another advantage is that the properties of the estimator used by the MCMC method do not depend on the stationarity of the time series. We assess the MCMC method through comparison with MLE, using a data set of 300 synthetic GPS-like time series and the JPL daily position time series for 90 GPS stations (the IGS core network). [less ▲]

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See detailPotential Contributions to Geoscience from GNSS Observations of the King Edward Point Geodetic Observatory, South Georgia, South Atlantic Ocean
Teferle, Felix Norman UL; Hunegnaw, Addisu UL; Ahmed, Furqan UL et al

Poster (2013, September 01)

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia, South Atlantic Ocean, through a University of Luxembourg funded research project and in ... [more ▼]

During February 2013 the King Edward Point (KEP) Geodetic Observatory was established in South Georgia, South Atlantic Ocean, through a University of Luxembourg funded research project and in collaboration with the United Kingdom’s National Oceanography Centre, British Antarctic Survey and Unavco, Inc. Due to its remote location in the South Atlantic Ocean, as well as, being one of few subaerial exposures of the Scotia plate, South Georgia Island has been a key location for a number of global monitoring networks, e.g. seismic, geomagnetic and oceanic. However, no geodetic monitoring station has been established, e.g. by the International Global Navigation Satellite System (GNSS) Service (IGS) community, despite the lack of such observations from this region. In this study we will present an evaluation of the GNSS observations from the KEP Geodetic Observatory for the period from February to August 2013. We calculate multipath and positioning statistics and compare these to those from IGS stations. The on-site meteorological data is compared to those from the nearby KEP meteorological station and global numerical weather models, and the impact of these data sets on delay and integrated water vapour estimates will be evaluated. We will discuss the installation in terms of its potential contributions to sea level observations using tide gauges and satellite altimetry, studies of tectonics, glacio-isostatic adjustment and atmospheric processes. [less ▲]

Detailed reference viewed: 93 (14 UL)
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See detailAntenna phase centre calibration effects on position time-series: preliminary results
Sidorov, Dmitry UL; Teferle, Felix Norman UL

Poster (2013, September 01)

Advances in GPS error modelling and the continued effort of re-processing have considerably decreased the scatter in position estimates over the last two decades. The associated reduction of noise in ... [more ▼]

Advances in GPS error modelling and the continued effort of re-processing have considerably decreased the scatter in position estimates over the last two decades. The associated reduction of noise in derived position time-series has revealed the presence of previously undetected periodic signals. It has been shown that these signals have frequencies related to the orbits of GPS satellites. A number of potential sources for these periodicities at the draconitic frequency and its harmonics have already been suggested in the literature and include, e.g. errors in the sub-daily tidal models, multipath and unresolved integer ambiguities. Due to the geometrical relationship between an observation point and an orbiting satellite, deficiencies in the modelling of electromagnetic phase centres of receiving antennas have the potential to also contribute to the discovered periodic signals. The change from relative to absolute type mean antenna/radome calibrations within the international GNSS service (IGS) lead to a significant improvement and the use of individual calibrations could add further refinements to computed solutions. However, at this stage providing individual calibrations for all IGS stations is not feasible. Furthermore, antenna near-field electromagnetic effects might out-weight the benefits of individual calibrations once an antenna is permanently installed. In this study we investigate the differences between position estimates obtained using individual and type mean antenna/radome calibrations as used by the IGS community. We employ position time-series derived from precise point positioning (PPP) as implemented in two scientific GNSS software packages. Our results suggest that the differences in the employed calibrations propagate directly into the position estimates, affecting both sub-daily and daily results and yielding periodic variations. The sub-daily variations have periods close to half a sidereal day and one sidereal day with amplitudes of up to 10 mm in all position components. The stacked power spectra of the daily difference time-series reveal peaks at the GPS draconitic frequency and its harmonics, having the associated amplitudes of up to 1 mm. Although these results are still preliminary, they confirm that small differences between individual and type mean antenna/radome calibrations propagate into position time series and may be partly responsible for the spurious signals with draconitic frequency and its harmonics. [less ▲]

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See detailBoundary elements for modelling gravitational signals observed by inter-satellite ranging
Antoni, M.; Weigelt, Matthias UL; Keller, W. et al

Poster (2013, September)

Detailed reference viewed: 58 (7 UL)
See detailEffizienz gleich Leistung? Analyse des Antwortverhaltens bei einem distraktorfreien Matrizentest.
Krieger, Florian UL; Kirmße, Alexander; Spinath, Frank M. et al

Poster (2013, September)

Anwendung effizienter Bearbeitungsstrategien abhängt. Bisherige Studien zeigen, dass strukturiertes und sequentielles Bearbeiten der Gestaltungsregeln nach aufsteigender Schwierigkeit zu einer besseren ... [more ▼]

Anwendung effizienter Bearbeitungsstrategien abhängt. Bisherige Studien zeigen, dass strukturiertes und sequentielles Bearbeiten der Gestaltungsregeln nach aufsteigender Schwierigkeit zu einer besseren Leistung führt. Während Bearbeitungsstrategien bislang durch Blickbewegungsstudien, Computersimulationen und die Methode des lauten Denkens ermittelt wurden, wurde in dieser Studie die Matrizenkonstruktionsaufgabe verwendet, bei der die Lösung in einer computerisierten Testumgebung generiert wird. Dies ermöglicht eine zeitgenaue und objektive Aufzeichnung des Prozesses der Antwortgenerierung. In Antwortprotokollen von 480 Probanden konnte mittels verschiedener Prozessindikatoren (Regelsprünge, Abweichung von erwarteter Bearbeitungsreihenfolge, Zurücksetzen generierter Lösungen, Ausmaß der Verwendung relevanter Gestaltungselemente) in einer multiplen Regression bis zu 28.8 % der Varianz der Testleistung aufgeklärt werden. Insbesondere strukturiertes und sequentielles Bearbeiten von Gestaltungsregeln sowie der Ausschluss irrelevanter Gestaltungselemente sind entscheidend für eine bessere Leistung. Entgegen bisheriger Befunde zeigt sich jedoch, dass die Bearbeitungsreihenfolge der Gestaltungsregeln nicht auf einer allgemeingültigen Schwierigkeit der Gestaltungsregeln beruht. [less ▲]

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See detailAutistic traits and emotion regulation
Pinto Costa, Andreia UL; Steffgen, Georges UL

Poster (2013, September)

Introduction: Individuals with Autism Spectrum Disorder (ASD) seem to have lower emotion regulation competence than typically developing individuals; they use more frequently suppression than reappraisal ... [more ▼]

Introduction: Individuals with Autism Spectrum Disorder (ASD) seem to have lower emotion regulation competence than typically developing individuals; they use more frequently suppression than reappraisal (Samson, Huber, & Gross, 2012). Additionally, low levels of resting heart rate variability (HRV) have been associated with poor social functioning and emotional rigidity (Butler, Wilhelm, & Gross, 2006), which characterize individuals with ASD. Therefore, it is hypothesized that typically developing individuals with more autistic traits use more frequently suppression instead of reappraisal and have lower resting HRV. Methodology: 66 students (age: M=21.73, SD=2.49) participated in the study. Firstly, participants resting HRV was measured for 5 minutes. Afterwards, participants watched 5 videos of one minute long each (Gross & Levenson, 1995). Two videos were used to elicit disgust and three were neutral. After each video, participants completed a questionnaire about the emotions felt during the video (Ekman, Friesen, & Ancoli, 1980; adapted by Gross & Levenson, 1993). Finally, participants completed the Autism-Spectrum Quotient (AQ; Baron-Cohen et al., 2001), and the Emotion Regulation Questionnaire (ERQ; Gross & John, 2003). Results: Participants who used more frequently suppression had more autistic traits (M=20.13, SD=4.73) than those who used more frequently reappraisal (M=15.06, SD=4.50; t(64)=3.80, p<.001). Furthermore, the more autistic traits participants had, the more they rated their emotions during the disgust-eliciting videos as pleasant (r(57)=.295, p<.05), and the more they reported feeling positive emotions (r(63)=.262, p<.05). However, no correlation was found regarding negative emotions. Concerning resting HRV participants with more autistic traits had higher HRV (r(47)=.29, p<.05). Conclusions: Similarly to individuals with ASD, typically developing individuals with more autistic traits used more frequently suppression, demonstrating less emotion regulation competence. The reported higher rates of pleasantness during the disgust-eliciting videos and the overall experience of more positive emotions can be interpreted as a lack of cognitive empathy (Baron-Cohen & Wheelwright, 2004). The unexpected resting HRV result might be explained by differences in the pattern of physiological responding (Zahn, Rumsey, & Kammen, 1987). [less ▲]

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See detailAssessing the Status of GNSS Data Processing Systems to Estimate Integrated Water Vapour for Use in Numerical Weather Prediction models
Ahmed, Furqan UL; Teferle, Felix Norman UL; Bingley, Richard et al

Poster (2013, September)

Modern Numerical Weather Prediction (NWP) models make use of the GNSS derived Zenith Total Delay (ZTD) or Integrated Water Vapour (IWV) estimates to enhance the quality of their forecasts. Usually, the ... [more ▼]

Modern Numerical Weather Prediction (NWP) models make use of the GNSS derived Zenith Total Delay (ZTD) or Integrated Water Vapour (IWV) estimates to enhance the quality of their forecasts. Usually, the ZTD is assimilated into the NWP models on hourly intervals but with the advancement of NWP models towards higher update rates, it has become necessary to estimate the ZTD on sub-hourly intervals. In turn, this imposes requirements related to the timeliness and accuracy of the ZTD estimates and has lead to a development of various strategies to process GNSS observations to obtain ZTD with different latencies and accuracies. Using present GNSS products and tools, ZTD can be estimated in real-time (RT), near real-time (NRT) and post-processing (PP) modes. The aim of this study is to provide an overview and accuracy assessment of various RT, NRT, and PP IWV estimation systems and comparing their achieved accuracy with the user requirements for GNSS meteorology. The NRT and PP systems are based on the Bernese GNSS Software v5.2 using a double-difference network and Precise Point Positioning (PPP) strategy, and the RT systems are based on BKG Ntrip Client 2.7 and PPP-Wizard both using PPP. One of the RT systems allows integer ambiguity resolution with PPP and therefore the effect of fixing integer ambiguities on ZTD estimates will also be presented. [less ▲]

Detailed reference viewed: 158 (11 UL)
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See detailFluctuation Relations and Crystallization in Colloidal Suspensions
Dorosz, Sven UL

Poster (2013, September)

Hard Spheres undergo a fluid to solid phase transition if the packing fraction is above $0.5$. The nucleation process itself and developing structures in this transient process are still matter of current ... [more ▼]

Hard Spheres undergo a fluid to solid phase transition if the packing fraction is above $0.5$. The nucleation process itself and developing structures in this transient process are still matter of current research. \\ Here a new approach is proposed to correlate forming structure and dissipation directly. The system driven externally by a time varying pressure is compressed in a finite time. Thermodynamic work measured and directly correlated to structural information recorded during the process. Fluctuation theorems set the framework of this analysis that still hold at the first order phase transition that are initialized by a macroscopic fluctuation. [less ▲]

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See detailEffect of grafted alumina nanoparticles on thermal and dynamic mechanical properties of the styrene-butadiene rubber
Sushko, Rymma UL; Baller, Jörg UL; Filimon, Marlena UL et al

Poster (2013, September)

Elastomers filled with hard nanoparticles are of great technical importance for the rubber industry. In general, fillers improve mechanical properties of polymer materials, e.g. elastic moduli, tensile ... [more ▼]

Elastomers filled with hard nanoparticles are of great technical importance for the rubber industry. In general, fillers improve mechanical properties of polymer materials, e.g. elastic moduli, tensile strength etc. The smaller the size of the particles the larger is the interface where interactions between polymer molecules and fillers can generate new properties. The aim of this contribution is to study the influence of the fillers’ surface treatment on the thermal and mechanical behavior of nanocomposites made of styrene-butadiene rubber (SBR). Three types of nanocomposites are investigated : (i) SBR-unmodified alumina, (ii) SBR – silanized alumina and (iii) SBR – alumina grafted to polymer chains. The surface-modified alumina nanoparticles were prepared using the method described in [1]. The grafting of the SBR chains to the alumina nanoparticles was realized by means of the procedures described in [2] and [3]. Temperature Modulated Differential Scanning Calorimetry (TMDSC) and Dynamic Mechanical Analysis (DMA) are well appropriated tools to investigate the thermal and dynamic glass transition behavior of the different nanocomposites, which is expected to be very sensitive to interfacial interactions between the nanoparticles and matrix molecules. TMDSC experiments reveal that all of the nanocomposites undergo a single glass transition. Thus, interphases induced by interfacial interactions do not manifest themselves by an additional glass transition unless it is hidden by the one of the matrix. Moreover, TMDSC measurements reveal that in general the glass transition temperature Tg depends in a complex manner on the concentration and surface treatment of the nanoparticles. The most important change of Tg is observed for the grafted nanocomposites: increasing the nanoparticle weight concentration beyond 4% yields an increase of Tg by 4 K. The corresponding slowing down of the molecular dynamics goes along with a significant decrease of the relaxator strength. More generally the presented results prove that, at the same filler concentration, the number of degrees of freedom freezing at the glass transition in case of un-grafted systems is practically independent on the chemical nature of the particles surface whereas it changes when there exist covalent bonds between the polymer molecules and the nanoparticles. DMA was used to probe the rheological behaviour of the nanocomposites under oscillatory shear. Isothermal frequency sweeps performed at different temperatures yield the real (G’) and imaginary (G”) parts of the complex shear modulus. Linear response regime conditions were strictly respected. The temperature-frequency equivalence principle was exploited to construct mastercurves for G’ and G” at the reference temperature T=273 K. As usual in polymers, three different behaviors were observed: the dynamic glass transition at high frequencies, the entanglement plateau at intermediary frequencies and viscoelastic “flowing” at very low frequencies. It generally appears that the filling of the SBR matrix with nanoparticles leads to an increase of the storage modulus that is more prominent in the rubbery region than in the glassy segment. While, in the low frequency regime, untreated and silanized alumina yield a mechanical behaviour that is rather near to the one of the neat SBR matrix, the grafting of elastomer molecules to the silanized fillers obviously induces a quasi-solid like response of the system. References: 1. Y.-Ch. Yang, S.-B. Jeong, B.-G. Kim, P.-R. Yoon, Powder Technology, 191, 117–121, 2009. 2. E. Passaglia, F. Donati, Polymer, 48, 35-42, 2007. 3. A. Bhattacharya, B. Misra, Prog. Polym. Sci. 29, 767–814, 2004. [less ▲]

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See detailFluctuation Relations and Crystallization
Dorosz, Sven UL

Poster (2013, August)

Hard Spheres undergo a fluid to solid phase transition if the packing fraction is approx. $>0.5$. The nucleation process itself and structure formation in this transient process are still under ... [more ▼]

Hard Spheres undergo a fluid to solid phase transition if the packing fraction is approx. $>0.5$. The nucleation process itself and structure formation in this transient process are still under investigation. Here a new approach is proposed to correlate forming structure and dissipation directly. Fluctuation relations are the method of choice. Increasing the pressure with time results in thermodynamic work, linked by the first law of thermodynamics to dissipation.\\ Studying fluctuation relations of structural phase transition and even slow dynamics is important. A new kind of fluctuation enters the dynamics that is macroscopic instead of microscopic based on thermal fluctuations. [less ▲]

Detailed reference viewed: 57 (1 UL)
Peer Reviewed
See detailModeling cellular ROS defense in mitochondrial-related diseases
Simeonidis, Vangelis UL; Kolodkin, Alexey UL; Ignatenko, Andrew UL et al

Poster (2013, July 22)

Reactive Oxygen Species (ROS) generation is an unavoidable background process during normal cellular function. The main contributor to ROS production is the electron transport chain, which reduces oxygen ... [more ▼]

Reactive Oxygen Species (ROS) generation is an unavoidable background process during normal cellular function. The main contributor to ROS production is the electron transport chain, which reduces oxygen to water. Some incompletely-reduced oxygen species escape and oxidize a variety of organic molecules, leading to molecular dysfunction and initiating a positive feedback loop of ever increasing active radical production. The increased concentration of ROS damages the mitochondria, therefore further elevating the rate of ROS generation. Healthy cells manage ROS enzymatically and by mitophagy of damaged mitochondria. The precise tuning of the latter mechanism is crucial for cell survival and is controlled by a ROS-induced regulatory network. We have built a set of kinetic models of varying complexity, based on the current understanding of the mechanism of cellular ROS defense. Our models allow simulation of various patho-physiological scenarios related to mitochondrial dysfunction and the failure of the system of ROS regulation in human cells. We employ the models we have constructed to simulate the effects of diseases related to mitochondrial dysfunction and excessive ROS generation, such as Parkinson’s disease, Huntington’s disease and cancer. Experimental evidence is used for model fitting, and we propose model improvements based on incorporation of single-cell experimental measurements. Finally, we discuss the perspective of integrating our kinetic models with genome-scale, constraint-based, tissue-specific models of metabolism, in order to study the effect of ROS misregulation on metabolic phenotype. [less ▲]

Detailed reference viewed: 154 (5 UL)
Peer Reviewed
See detailBilingualism Enriches the Poor: Enhanced Cognitive Control in Low-Income Minority Children
Engel de Abreu, Pascale UL; Cruz-Santos, A; Tourinho De Abreu Neto, Carlos José UL et al

Poster (2013, June 24)

This study explores whether the cognitive advantage associated with bilingualism in executive functioning extends to young children challenged by poverty and if so, which specific processes are most ... [more ▼]

This study explores whether the cognitive advantage associated with bilingualism in executive functioning extends to young children challenged by poverty and if so, which specific processes are most affected. Forty Portuguese-Luxembourgish bilingual children from low-income immigrant families in Luxembourg and 40 matched monolingual children from Portugal completed visuo-spatial tests of working memory, abstract reasoning, selective attention, and interference suppression. Two broad cognitive factors of executive functioning labeled representation (abstract reasoning and working memory) and control (selective attention and interference suppression) emerged from principal components analysis. Whereas there were no group differences in representation, the bilinguals performed significantly better than the monolinguals in control. These results demonstrate first, that the bilingual advantage is neither confounded with nor limited by socioeconomic and cultural factors and second, that separable aspects of executive functioning are differentially affected by bilingualism. The bilingual advantage lies in control but not in visuo-spatial representational processes. [less ▲]

Detailed reference viewed: 110 (14 UL)
See detailAnomalous behaviour of SBR/Al2O3 nanocomposites at small filler concentrations
Sushko, Rymma UL; Baller, Jörg UL; Filimon, Marlena UL et al

Poster (2013, June)

Elastomers filled with hard nanoparticles are of great importance for the rubber industry. In general, the incorporation of the small particles improves the mechanical properties of polymeric materials, e ... [more ▼]

Elastomers filled with hard nanoparticles are of great importance for the rubber industry. In general, the incorporation of the small particles improves the mechanical properties of polymeric materials, e.g. elastic modulus, tensile strength etc. Nanocomposites made of poly(styrene-co-butadiene) and alumina nanoparticles (unmodified and modified with different silane coupling agents) were investigated by temperature modulated differential scanning calorimetry (TMDSC) and dynamic mechanical analysis (DMA). It has been shown that the glass transition behaviour of SBR/alumina nanocomposites differs when the concentration and surface properties of the Al2O3 nanoparticles are changed. The influence of the fillers on the shear stiffness of the rubber material was also investigated. TMDSC investigations shed light on a surprising behaviour of the glass transition temperature when the nanoparticle concentration is changed: at low filler contents the quasi-static glass transition temperature Tg passes through a minimum. While further increasing the nanoparticle content Tg increases to finally saturate at high concentrations. DMA results showed a quasi-solid-like frequency-independent response of the nanocomposites in the low frequency regime with increasing of the filler concentration. [less ▲]

Detailed reference viewed: 65 (2 UL)
Full Text
See detailModifications of the Simpson moduli spaces of 1-dimensional sheaves on a projective plane by vector bundles
Iena, Oleksandr UL

Poster (2013, June)

We study how to modify the Simpson moduli spaces of 1-dimensional coherent sheaves on a projective plane in order to obtain a space of vector bundles on curves.

Detailed reference viewed: 29 (1 UL)
Peer Reviewed
See detailHow the human brain discriminates numerosities: A steady-state visual-evoked potentials study
Mejias, Sandrine; Rossion, Bruno; Schiltz, Christine UL

Poster (2013, May 28)

This study aimed at measuring rapidly and objectively human adults' sensitivity to (non)symbolic numerical stimuli, using the steady-state visual-evoked potentials (1) response in the context of ... [more ▼]

This study aimed at measuring rapidly and objectively human adults' sensitivity to (non)symbolic numerical stimuli, using the steady-state visual-evoked potentials (1) response in the context of repetition suppression (2). It aimed to demonstrate the feasibility of the method and evaluate its potential to tap into the basic numerical representation systems that can be assumed to underlie symbolic and non-symbolic magnitude comparisons. Following a short duration experiment, we observed a large reduction of signal specifically at the 3.5 Hz response, over the occipito-temporo-parietal cortex. This reduction was greater for symbolic than non-symbolic control stimuli. This first observation of repetition suppression to fast periodic stimulation of symbolic and non-symbolic numerosities in the human brain offers a promising tool to study the sensitivity to numerosities in the human brain in adults, but also especially in children. [less ▲]

Detailed reference viewed: 29 (1 UL)
Peer Reviewed
See detailMental disorders and personality characteristics in parents of patients with eating disorders
Rost, Silke UL; Kappel, Viola; Schneider, Nora et al

Poster (2013, May 25)

Detailed reference viewed: 32 (2 UL)
See detailRelaxation times and electron-phonon interaction in graphene quantum dots
Reichardt, Sven UL; Volk, Christian; Neumann, Christoph et al

Poster (2013, May 23)

Detailed reference viewed: 78 (1 UL)
Peer Reviewed
See detailSpezifität der Körperbildstörung für Anorexia nervosa
Rost, Silke UL; Jaite, Charlotte; Sarrar, Lea et al

Poster (2013, May 10)

Detailed reference viewed: 85 (6 UL)