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See detailmstR: An R package to generate multistage testing designs
Magis, David ULg; Yan, Duanli; von Davier, Alina

Conference (2017, July 18)

Multistage testing (MST; Yan, von Davier & Lewis, 2014) has become an important framework of tailored testing. Similarly to computerized adaptive testing (CAT) it proposes an optimal routing of the ... [more ▼]

Multistage testing (MST; Yan, von Davier & Lewis, 2014) has become an important framework of tailored testing. Similarly to computerized adaptive testing (CAT) it proposes an optimal routing of the administered items according to the previous test taker’s responses. However, items are not selected and administered as single units but as modules (subsets). The main goal of MST consists in selecting the optimal path of modules across the successive stages of the test. Unfortunately, if various operational testing programs are nowadays considering MST for practical administrations, there is still very limited access to accurate software that can either treat or generate MST scenarios for research purposes. In this talk we succinctly present a new package from the R software, called mstR (Magis, Yan & von Davier, 2017). Built in the same spirit of the package catR for CAT designs, it permits to generate repeated response patterns under a predefined MST scenario by providing the set of modules and related item parameters, the number of stages and the connections between modules from successive stages. Several rules for optimal module selection and ability estimation (under IRT framework or based on test scores) are also available. This talk will mostly focus on the (non-technical) description of package mstR and its main features. An example will also be described as an illustration of this framework. [less ▲]

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See detailNegative velocity fluctuations and non-equilibrium fluctuation relation for a driven high critical current vortex state
Bag, Biplab; Shaw, Gorky ULg; Banerjee, S. S. et al

in Scientific Reports (2017), 7(1), 5531

Under the influence of a constant drive the moving vortex state in 2H-NbS2 superconductor exhibits a negative differential resistance (NDR) transition from a steady flow to an immobile state. This state ... [more ▼]

Under the influence of a constant drive the moving vortex state in 2H-NbS2 superconductor exhibits a negative differential resistance (NDR) transition from a steady flow to an immobile state. This state possesses a high depinning current threshold ( $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h ) with unconventional depinning characteristics. At currents well above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h , the moving vortex state exhibits a multimodal velocity distribution which is characteristic of vortex flow instabilities in the NDR regime. However at lower currents which are just above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h , the velocity distribution is non-Gaussian with a tail extending to significant negative velocity values. These unusual negative velocity events correspond to vortices drifting opposite to the driving force direction. We show that this distribution obeys the Gallavotti-Cohen Non-Equilibrium Fluctuation Relation (GC-NEFR). Just above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h , we also find a high vortex density fluctuating driven state not obeying the conventional GC-NEFR. The GC-NEFR analysis provides a measure of an effective energy scale (E eff ) associated with the driven vortex state. The E eff corresponds to the average energy dissipated by the fluctuating vortex state above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h . We propose the high E eff value corresponds to the onset of high energy dynamic instabilities in this driven vortex state just above $$\boldsymbolI_\boldsymbolc^\boldsymbolh$$ I c h . [less ▲]

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See detailPrevention Library and Resources in four languages (QP Library)
Comité de Bibliografía en Prevención Cuaternaria; WONCA SIG P4 & O; Pizanelli, Miguel et al

Textual, factual or bibliographical database (2017)

Since Quaternary Prevention is very extensive and complex, during the design process for database input, an indexing structure with the use of coding tools and categories was considered. This design will ... [more ▼]

Since Quaternary Prevention is very extensive and complex, during the design process for database input, an indexing structure with the use of coding tools and categories was considered. This design will allow the addition of materials and will provide easy access to them. To add documents, 13 data fields must be populated. To access the input data form, for the purpose of adding documents, use this link: http://j.tinyurl.com/P4-Library To avoid duplication of data entries, it is necessary to review and perform an audit. In the beginning, we will provide this tutorial to a few data entry collaborators. To become a data entry collaborator, please send an e-mail to the following address: quaternaryprevention@gmail.com Charts are available in eight languages to code with Q-Codes: http://3cgp.docpatient.net/tabular/ [less ▲]

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See detailGlobal regression model for moisture content determination using near-infrared spectroscopy
Clavaud, Matthieu ULg; Roggo, Yves; Degardin, Klara et al

in European Journal of Pharmaceutics and Biopharmaceutics (2017)

Near-infrared (NIR) global quantitative models were evaluated for the moisture content (MC) determination of three different freeze-dried drug products. The quantitative models were based on 3822 spectra ... [more ▼]

Near-infrared (NIR) global quantitative models were evaluated for the moisture content (MC) determination of three different freeze-dried drug products. The quantitative models were based on 3822 spectra measured on two identical spectrometers to include variability. The MC, measured with the reference Karl Fischer (KF) method, were ranged from 0.05% to 4.96%. Linear and non-linear regression models using Partial Least Square (PLS), Decision Tree (DT), Bayesian Ridge Regression (Bayes-RR), K-Nearest Neighbors (KNN), and Support Vector Regression (SVR) algorithms were created and evaluated. Among them, the SVR model was retained for a global application. The Standard Error of Calibration (SEC) and the Standard Error of Prediction (SEP) were respectively 0.12% and 0.15%. This model was then evaluated in terms of total error and risk-based assessment, linearity, and accuracy. It was observed that MC can be fastly and simultaneously determined in freeze-dried pharmaceutical products thanks to a global NIR model created with different medicines. This innovative approach allows to speed up the validation time and the in-lab release analyses. [less ▲]

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See detailEffects of an experimental resource pulse on the macrofaunal assemblage inhabiting seagrass macrophytodetritus
Remy, François ULg; Gobert, Sylvie ULg; Lepoint, Gilles ULg

in Belgian Journal of Zoology (2017), 147(1), 1-15

Physical disturbances and resource pulses are major structuring drivers of terrestrial and aquatic ecosystems. The accumulations of exported dead leaves from the Neptune grass, Posidonia oceanica (L ... [more ▼]

Physical disturbances and resource pulses are major structuring drivers of terrestrial and aquatic ecosystems. The accumulations of exported dead leaves from the Neptune grass, Posidonia oceanica (L.) Delile are ephemeral and highly dynamic detrital habitats offering food sources and shelter for vagile macrofauna community. These habitats are frequently subject to wind and storms which can add “new” detrital material to previous accumulations; these can be defined as resource pulses and could potentially impact the associated macrofauna. This study assesses the impact of an experimental resource pulse on the macrofauna associated with exported P. oceanica litter accumulations. The experimental design consisted of two pulse treatments (the addition of dead leaves with and without the associated fauna), and two controls (one procedural, and one total control), where the added material was left underwater for 14 days. Invertebrates then present in the sampled detritus were all identified and counted. Our data suggest that the responses of these invertebrates to resource pulses present intermediate characteristics between aquatic and terrestrial ecosystems responses. Inputting a moderate amount of dead P. oceanica leaves into experimental mesocosms had a non-negligible impact and rapidly affected the macrofauna community. Specialist detritivores species were boosted while herbivore/detritivore species dramatically decreased. Predators also showed a modest but significant density increase, demonstrating the fast propagation of the pulse response throughout the entire community and through several trophic levels. Strict hypoxia-tolerant species were also only observed in the treated mesocosms, indicating the strong influence of resource pulses on physico-chemical conditions occurring inside litter accumulations. [less ▲]

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See detailCosmological Time, Entropy and Infinity
Hauret, Clémentine ULg; Magain, Pierre ULg; Biernaux, Judith ULg

in Entropy (2017), 19(7),

Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative ... [more ▼]

Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motion and on the strength of the gravitational field in which they are embedded. In standard cosmology, the time parameter is the one measured by fundamental clocks (i.e., clocks at rest with respect to the expanding space). This proper time is assumed to flow at a constant rate throughout the whole history of the universe. We make the alternative hypothesis that the rate at which the cosmological time flows depends on the dynamical state of the universe. In thermodynamics, the arrow of time is strongly related to the second law, which states that the entropy of an isolated system will always increase with time or, at best, stay constant. Hence, we assume that the time measured by fundamental clocks is proportional to the entropy of the region of the universe that is causally connected to them. Under that simple assumption, we find it possible to build toy cosmological models that present an acceleration of their expansion without any need for dark energy while being spatially closed and finite, avoiding the need to deal with infinite values. [less ▲]

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See detailA Novel Accelerometer-Based Method for Stride Length Estimation
Boutaayamou, Mohamed ULg; Schwartz, Cédric ULg; Denoël, Vincent ULg et al

Poster (2017, July 14)

We demonstrate the feasibility of accurately and precisely estimating the left/right average stride length from measured heel/toe accelerations in the gait of healthy, old adults. Our approach relies on ... [more ▼]

We demonstrate the feasibility of accurately and precisely estimating the left/right average stride length from measured heel/toe accelerations in the gait of healthy, old adults. Our approach relies on (1) a novel method that uses only accelerometer data without the need of additional data from, e.g., gyroscopes and/or magnetometers, and on (2) the validation of the results using reference 3D optoelectronic system data. [less ▲]

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See detailUndoing Art
Delville, Michel ULg

Conference (2017, July 13)

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See detailHighly efficient doped nanocristalline TiO2 for water Treatment
Mahy, Julien ULg; Léonard, Géraldine ULg; Zubiaur, Anthony ULg et al

Conference (2017, July 13)

Detailed reference viewed: 28 (5 ULg)
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See detailDu dessin au design. Seth comme auteur-rééditeur
Crucifix, Benoît ULg

Conference (2017, July 13)

Depuis ces dernières années, l’édition de bande dessinée connaît un véritable boom de rééditions patrimoniales. Dans le contexte nord-américain, ce sont justement les auteurs associés au « roman ... [more ▼]

Depuis ces dernières années, l’édition de bande dessinée connaît un véritable boom de rééditions patrimoniales. Dans le contexte nord-américain, ce sont justement les auteurs associés au « roman graphique » – ceux-là même qui ont exploré le livre en tant qu’objet en réalisant eux-mêmes le design de leurs œuvres – qui sont aussi invités à prendre en charge la conception graphique de ces rééditions d’œuvres du passé qu’ils aident à faire (re)découvrir. Cette communication a pour but d’étudier les designs réalisés par l’auteur canadien Seth pour plusieurs œuvres complètes : The Complete Peanuts, The John Stanley Library et The Collected Doug Wright. Les designs de Seth se caractérisent par leur mise-en-avant d’une esthétique idiosyncratique, comme il l’a lui-même exprimé : « when I design something it really is too much about me » (Spurgeon, 143). Elles se lient donc intimement à la production « propre » de l’auteur. Dans le cas de Stanley et Doug Wright, ces rééditions sont d’ailleurs liées à des essais écrits par Seth, relevant d’un travail autant esthétique qu’historiographique. Il s’agira d’abord de comprendre la spécificité culturelle de cette pratique de réédition dans l’édition « alternative » américaine, qui diffère du contexte éditorial européen ; plus en avant, le cas de Seth permettra de comprendre comment cette pratique ressort d’un mécanisme de canonisation particulier (Heer), mais aussi de montrer à quel point ce type d’objets met en avant une « fonction-auteur » (Foucault) inextricablement liée à une activité historiographique, éditoriale et patrimoniale. [less ▲]

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See detailPanel “Quand la bande dessinée se reproduit : imitation, reprise et rétro-réflexivité”
Crucifix, Benoît ULg; Busi-Rizzi, Giorgio

Diverse speeche and writing (2017)

Co-organisation et présidence du panel "Quand la bande dessinée se reproduit : imitation, reprise et rétro-réflexivité" – Dans une industrie culturelle basée sur les principes de série et d’imitation, les ... [more ▼]

Co-organisation et présidence du panel "Quand la bande dessinée se reproduit : imitation, reprise et rétro-réflexivité" – Dans une industrie culturelle basée sur les principes de série et d’imitation, les questions de reproduction occupent une place toute particulière, illustrée par ce terme spécifique de swipe utilisé dans l’industrie du comic book. L’imitation s’est instituée comme principe éditorial autant dans la bande dessinée nord-américaine que dans la bande dessinée franco-belge : le style graphique se constitue ainsi souvent par imitation et reproduction, comme le montre l’exemple de l’émulation des styles ‘singuliers’ d’artistes tels que Jack Kirby ou André Franquin. Les rééditions des œuvres du passé tout comme les reprises de série classique s’épanouissent aujourd’hui et, simultanément, la bande dessinée s’empare de plus en plus de son propre passé, invoquant les connaissances encyclopédiques de ses lecteurs et s’engageant dans une forme de « rétro-réflexivité » (Brett Camper). Ces pratiques de reproduction par imitation indiquent différentes manières de penser la mise-à-disposition du passé dans le présent. Elles négocient ainsi de façon spécifique et historique le rapport à la reproductibilité en bande dessinée, par le biais de diverses techniques (recopiage, décalquage, collage, dessin, détournement, réinterprétation graphique, photocopie, clins d’œil, copier/coller, etc.) : à chaque fois, elles semblent alors interroger le rapport entre dessin et reproduction, que celle-ci soit manuelle, mécanique ou numérique. Cette session portera sur la prégnance de la reproduction par imitation dans la bande dessinée afin d’en examiner les enjeux culturels et esthétiques qui la lient à son passé et à son histoire. Comment la bande dessinée se reproduit-elle elle-même ? Quelles sont les pratiques de citation qui lui sont propres ? Comment ce rapport au passé a-t-il changé ? [less ▲]

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See detailNon-pathological aging of the executive functions: influence of the Val108/158Met nucleotide polymorphism of the COMT gene
Gilsoul, Jessica ULg; Manard, Marine ULg; Collette, Fabienne ULg

Poster (2017, July 13)

Objectives. The aim of the study is to investigate the influence of the COMT Val108/158Met nucleotide polymorphism, associated with dopaminergic regulation, on executive functions in normal aging. Indeed ... [more ▼]

Objectives. The aim of the study is to investigate the influence of the COMT Val108/158Met nucleotide polymorphism, associated with dopaminergic regulation, on executive functions in normal aging. Indeed, according to the Dual-State Theory, Val/Val polymorphism of the COMT gene would favor better flexibility abilities, whereas Met/Met carriers would favor better stability abilities. These genotypic effects should be magnified in older people, as a decrease in cognitive resources increases the influence of individual genetic differences on cognitive performance. Method. We assessed the executive processes of inhibition, shifting, and updating – thanks to many different tasks in groups of young (n = 55) and aged participants (n = 45) carrying one of the three polymorphism of the COMT gene (Val/Val, Val/Met, Met/Met). T-tests between our two groups (Young versus Aged) but also a 6 (Group: Young-Met/Met, Young-Val/Met, Young- Val/Val, Old-Met/Met, Old-Val/Met, and Old-Val/Val) X 3 (Executive functioning: Inhibition, Shifting, and Updating) repeated measure ANOVA with Executive functioning as within-subject factor (p < .05) were carried out. Results. Young and old participants significantly differed on the three executive functions. The comparison of genotypic groups showed no significant differences in young or older participants respectively. Interestingly, the Old-Val/Val group showed a lower performance than the young one on inhibition tasks. Conclusion. As expected, we found an age effect on all the executive functions. The significant difference between the Young-Val/Val and the Old-Val/Val groups on inhibition suggests an age-related decrease in abilities requiring a stability component in individuals possessing a less favoring genotype for this component. [less ▲]

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