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See detailGenome-Wide Association Interaction Analysis for Alzheimer’s Disease
Gusareva, Elena ULg; Carrasquillo, Minerva M.; Bellenguez, Céline et al

in Neurobiology of Aging (2014)

We propose a minimal protocol for exhaustive genome-wide association interaction analysis that involves screening for epistasis over large-scale genomic data combining strengths of different methods and ... [more ▼]

We propose a minimal protocol for exhaustive genome-wide association interaction analysis that involves screening for epistasis over large-scale genomic data combining strengths of different methods and statistical tools. The different steps of this protocol are illustrated on a real-life data application for Alzheimer's disease (AD) (2259 patients and 6017 controls from France). Particularly, in the exhaustive genome-wide epistasis screening we identified AD-associated interacting SNPs-pair from chromosome 6q11.1 (rs6455128, the KHDRBS2 gene) and 13q12.11 (rs7989332, the CRYL1 gene) (p = 0.006, corrected for multiple testing). A replication analysis in the independent AD cohort from Germany (555 patients and 824 controls) confirmed the discovered epistasis signal (p = 0.036). This signal was also supported by a meta-analysis approach in 5 independent AD cohorts that was applied in the context of epistasis for the first time. Transcriptome analysis revealed negative correlation between expression levels of KHDRBS2 and CRYL1 in both the temporal cortex (β = -0.19, p = 0.0006) and cerebellum (β = -0.23, p < 0.0001) brain regions. This is the first time a replicable epistasis associated with AD was identified using a hypothesis free screening approach. [less ▲]

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See detailThe Authority of Human Rights Case Law from the Perspective of the International Criminal Judge
Deprez, Christophe ULg

Scientific conference (2014, May 28)

This brief presentation addressed the question of the legal value of European human rights jurisprudence from the perspective of the international criminal judge.

Detailed reference viewed: 13 (1 ULg)
See detailSynthesis of hybrid nanoparticles for theranostics
Liu, Ji ULg; Detrembleur, Christophe ULg; Duguet, Etienne et al

Conference (2014, May 28)

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See detailDesign of a spherical array of microphones for room acoustics applications.
Feron, Hermine; Embrechts, Jean-Jacques ULg

Conference (2014, May 28)

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See detailRegulation in Practice: Choice among regulatory Tools
Bougnouch, Mehdi ULg; Gautier, Axel ULg

Conference (2014, May 28)

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See detailPréférences résidentielles et production du logement en banlieue périurbaine
Halleux, Jean-Marie ULg; Strée, Julie

Conference (2014, May 27)

La communication traitera des relations entre les mécanismes de la production immobilière et les préférences résidentielles. Elle visera à vérifier l’hypothèse selon laquelle nous assistons à l’émergence ... [more ▼]

La communication traitera des relations entre les mécanismes de la production immobilière et les préférences résidentielles. Elle visera à vérifier l’hypothèse selon laquelle nous assistons à l’émergence et au renforcement de préférences susceptibles de remettre en cause le modèle périurbain du pavillon périphérique. Notre propos s’inscrit donc dans la réflexion sur le futur des zones périurbaines (Grant et al., 2013). Notre recherche a consisté dans la réalisation et l’analyse d’une enquête menée au sein de la zone métropolitaine de Bruxelles, auprès de ménages habitant un logement neuf (Strée et Halleux, 2013). Les ménages ont été interrogés sur leurs préférences résidentielles ainsi que sur leurs propensions à payer pour différents types de produits immobiliers. Son échantillon est constitué de 120 ménages ayant été interrogés en face à face à leur domicile. L’échantillon a été stratifié en fonction de deux critères : la localisation au sein de la zone métropolitaine et le type de logements. Concernant la localisation, des enquêtes ont été menées à Wavre (commune située à une demi-heure voiture du centre de Bruxelles) et en plus lointaine périphérie, à Perwez et Chastre (communes situées à une heure voiture du centre de Bruxelles). Concernant les types de logement, la stratification s’est opérée de la manière suivante : 40 % des ménages résident dans une habitation quatre façades, 30 % dans une habitation mitoyenne et 30 % dans un appartement. Un premier résultat de notre enquête est de confirmer la prégnance du modèle de la maison unifamiliale isolée (quatre façades), qui représente le logement idéal pour 69 % de l’échantillon (y compris par 70 % des ménages résidant dans une habitation mitoyenne et par 57 % des ménages résidant en appartement). Pour autant, en comparaison d’enquêtes précédentes, les propensions à payer témoignent d’une bonne acceptation des produits immobiliers alternatifs. Sur base d’enquêtes précédentes réalisées dans le périurbain de Liège, nous nous attendions à une moins-value de 15 à 20 % entre le produit de la maison isolée et le produit de la maison jointive. Or, la différence observée est ici inférieure à 10 %. Cette situation est à relier à la problématique de la disponibilité en zones constructibles (Halleux et Strée, 2012). En effet, le bassin d’emploi bruxellois se caractérisant par une faible disponibilité foncière, cela conduit à banaliser la promotion commerciale de logements jointifs. Au sein de ces territoires, les ménages auraient donc bien intégré ce type de développements. Au sein d’autres territoires aux marchés fonciers moins tendus, nous aurions probablement observé des consentements à payer plus élevés pour la maison isolée, consentements qui auraient alors pu être interprétés comme un signe de stigmatisation vis-à-vis du logement jointif. Au final, nous mettons en avant un effet systémique où, par son impact sur la multiplication des projets de maisons mitoyennes, la rareté de l’offre foncière conduit à renforcer l’acceptation de la demande pour ce type de produits immobiliers. Parmi les autres résultats de notre enquête, soulignons la forte valorisation de la maison de 100 m2 qui, en comparaison d’appartements de la même superficie, est valorisée à un niveau moyen 13 % supérieur. Il existe donc un potentiel commercial important pour la petite maison. Cela représente à la fois une menace pour la consommation d’espace et une opportunité pour la densification douce. Il ressort également de nos enquêtes qu’une localisation intra-urbaine (dans un quartier « ancien ») est fortement dévalorisée. Pour autant, un signal encourageant tient ici à la relation entre l’âge du répondant et cette dévalorisation : les effectifs de moins de 40 ans dévalorisent moins les quartiers densément bâti que les populations plus âgées. Il s’agit là d’un résultat qui s’inscrit dans l’hypothèse de Grant et al. (2013) quant au renforcement de la demande pour des localisations plus urbaines et plus centrales. [less ▲]

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See detailCorrelation and integration of the Rorschach Comprehensive System and the TCI-R questionnaire
Rentmeister, Daniel; Blavier, Adelaïde ULg; Di Piazza, Laetitia ULg et al

Poster (2014, May 27)

In this study, a dual purpose is sought. First, we statistically compare the Rorschach test interpreted by the Comprehensive System from J.E. Exner and the Temperament and Character Inventory – Revised by ... [more ▼]

In this study, a dual purpose is sought. First, we statistically compare the Rorschach test interpreted by the Comprehensive System from J.E. Exner and the Temperament and Character Inventory – Revised by R. Cloninger to highlight their differences and similarities. Second, through clinical cases, we discuss the relevance of integrating the results obtained by these two tools to establish a comprehensive and consistent psychological profile of an individual. For the statistical comparison, a sample of 27 “healthy” subjects (M = 24.37 years, SD = 2.75) was first submitted to the Rorschach test. Then, immediately after, each subject completed the TCI-R. A correlation analysis (Pearson Rho) was done between various Index and a Bonferroni adjustment was made. For the case studies, 3 subjects were recruited. Anamneses were carried out and the Rorschach test and TCI-R administered. Our first results, which are to be taken with caution because of the small number of subjects in the sample, must be qualified and discussed. From 2448 statistical comparisons, we select the most relevant and discuss different correlation results. The case studies show a concordance in social relationships and impulsivity; and show that the information peculiar to each test allows us to complete the subject’s profile. Finally, it is by addressing two different epistemologies underlying these two tests that we can best explain the psychological differences highlighted in the same individuals. We conclude by suggesting that this difference in results must certainly be understood in an integrative logic and emphasizes the complementarity between these two tests. [less ▲]

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See detailLong protocols to Rorschach Comprehensive System and a posteriori reduction of number of responses: What is the impact on the clinical interpretation ?
Dufour, Cristelle; Englebert, Jérôme ULg; Blavier, Adelaïde ULg

Poster (2014, May 27)

Our study was interested in the exceptionally long protocols, superior to 55 answers, supplied by five subjects in the test of Rorschach according to the method of the Comprehensive System. In order to ... [more ▼]

Our study was interested in the exceptionally long protocols, superior to 55 answers, supplied by five subjects in the test of Rorschach according to the method of the Comprehensive System. In order to gain understanding of which attitude to adopt in front of this kind of protocol, we made a a posteriori reduction of the number of answers by basing us on the recommendations of Exner (Exner, on 2001), then a comparative study between the clinical interpretation realized with all of the answers and with only the first five answers by board. We also replicate this methodology of a posteriori decrease of the number of answers with four answers by board according to the new recommendations of the system R-PAS of Meyer and al. (Meyer and al, on 2009). The sample consists of three raw coal subjects and two psychiatric subjects. Our analysis highlighted a stability of certain variables (EB, Lambda, EA for example) but a difference in the psychological profile of the subjects after reduction. We observed a clarification of the fundamental difficulties to the psychiatric subjects and rather a neutralization of these difficulties for the raw coal subjects, with particularly defence mechanisms which seem more adapted. In our sample, the consideration of all of the answers or only of the partial protocol thus brings a difference in the clinical interpretation ; as a consequence any reduction should be made with big caution. Our study allows to discuss current practices of the test of Rorschach, by looking for a compromise between the inherent constraints to the validity of the test and the questions of the clinical complexity decrease appropriate to any initiative of standardization. [less ▲]

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See detail[18F]UCB-H AS A BRAIN SV2A RADIOTRACER: A FIRST CLINICAL TRIAL
Bahri, Mohamed Ali ULg; Bastin, Christine ULg; Aerts, Joël ULg et al

Poster (2014, May 27)

[18F]UCB-H is a fluorine-18 radiolabelled PET imaging tracer with a high affinity for the synaptic vesicle protein 2A (SV2A). This protein, involved in vesicle trafficking and widely distributed in the ... [more ▼]

[18F]UCB-H is a fluorine-18 radiolabelled PET imaging tracer with a high affinity for the synaptic vesicle protein 2A (SV2A). This protein, involved in vesicle trafficking and widely distributed in the brain, represents the binding site and the primary mechanism of the antiepileptic drug levetiracetam. Levetiracetam has recently been suggested to reduce synaptic deficits in a mouse Alzheimer’s disease model and to improve cognition in patients with amnestic mild cognitive impairment, suggesting a possible role for this protein in synaptic integrity. The objective of this study was to investigate the cerebral distribution of [18F]UCB-H in healthy human volunteers. Dynamic PET imaging of the head of four healthy volunteers was performed over 100 minutes after injection of 170.4 ± 24.9 MBq of GMP produced [18F]UCB-H. The input function was acquired by arterial blood sampling during the dynamic PET acquisition. Blood data analysis showed a consistent tracer amount in whole blood and plasma indicating a very low degree of binding of the tracer to the red blood cells. Unchanged [18F]UCB-H fraction in plasma follows a bi-exponential behavioral decrease with a starting fraction of 92% of the injected amount of the tracer, measured at 3 min post injection. This fraction decreases to about 50% at 10 min post injection. The [18F]UCB-H PET data revealed a high and rapid uptake in the grey matter structures, matching the known ubiquitous distribution of SV2A in the brain. The kinetics of the tracer in the brain was characterized by an initial high uptake phase followed by rapid washout allowing the standard compartmental modeling (1-tissue compartment, 2-tissue compartment, and Logan graphical analysis). The three models gave consistent results. The two-tissue compartment model fitted the experimental data best and provided a total distribution volume of [18F]UCB-H in the brain greater than 7 mL/cm3 and a specific distribution volume around 3 mL/cm3. Our results indicate that [18F]UCB-H is a new radiotracer for brain SV2A proteins suitable for human studies. Further studies are warranted to assess SV2A modifications in neurological pathologies such as Alzheimer’s disease. [less ▲]

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See detailPuissances émergentes : quel rôle dans la gouvernance mondiale ?
Santander, Sébastian ULg

Scientific conference (2014, May 27)

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See detailJuvenile sexual offenders: Can their language tell us how their mind works?
Courtain, Audrey; Glowacz, Fabienne ULg

Poster (2014, May 27)

A significant proportion of sexual delinquency being committed by juveniles, various fields of research have studied this topic. Still, little is known about the relation between the linguistic ability ... [more ▼]

A significant proportion of sexual delinquency being committed by juveniles, various fields of research have studied this topic. Still, little is known about the relation between the linguistic ability and the cognitive functioning of this specific youth. Rooted in scientific works which have explored indirectly the point, this poster attempt to question the quality of language as a mean to find out how their mentalization occurs, but also to question how their cognitive processes (e.g. empathy) influence their language. These hypothesis are to be tested soon with a clinical sample of 47 participants and with different measures (e.a. MACI, verbal IQ, IRI). Hence, the opportunity to evaluate, among others, empathy deficits and cognitive distortions through language can be considered a promising approach allowing new perspectives for prevention, assessment and treatment of juvenile sexual offenders. [less ▲]

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See detailTemplating calcium carbonate drug delivery carriers based on polyphosphoester copolymers
Ergül, Zeynep ULg; Debuigne, Antoine ULg; Caalvignac, Brice et al

Poster (2014, May 27)

The design of drug delivery systems (DDS) often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, CaCO3 particles are ... [more ▼]

The design of drug delivery systems (DDS) often requires biodegradable and biocompatible materials that allow safe retention and controlled release of the drug. In this respect, CaCO3 particles are appropriate drug carriers that have excellent properties such as low density, high specific surface areas and porosity for drugs and proteins encapsulation. Here, hyaluronic acid usually used for templating CaCO3 particles was substituted by a degradable synthetic copolymer based on PPE. The latter is a promising candidate due to its biocompatibility, biodegradability and the low toxicity of its degradation products such as phosphates. We also introduced acid functions on the PPE segment in order to enhance its calcium affinity and ability to tune the morphology of the CaCO3 particles. The butynyl phospholane (BYP) polymerization was initiated from poly(ethylene oxide) PEO-OH by organocatalyzed ring opening polymerization (ROP) [2] followed by UV catalyzed thiol-yne addition of 3-mercaptopropionoic acid onto the alkyne functions. CaCO3 particles were then generated in the presence of the copolymer following a procedure inspired from . Well-defined PPE copolymers bearing pendant alkynyl groups, i.e. PEO-b-PBYP (Ð <1.1), were obtained by organocatalyzed ROP of BYP initiated at 0°C from PEO-OH (Scheme 1). The copolymer was then reacted under UV with 3-mercaptopropionoic acid in order to introduce carboxylic acid functions along the PPE backbone by thiol-yne reaction. NMR analyses confirmed that full functionalization was reached after 2h. The high density of acid moieties in PEO-b-PBYP(COO-)2 is supposed to facilitate the Ca2+ complexation. The solution behavior and self-assembly of PEO-b-PBYP(COO-)2 in water was investigated by DLS with and without Ca+2 at different pH. Finally, stoichiometric amounts of CaCl2 and Na2CO3 were mixed in water containing the PEO-b-PBYP(COO-)2 which strongly influences the size of the CaCO3 particles (~1.5 µm). The acid-bearing PPE-based copolymers were successfully prepared and used as templating agents for the synthesis of CaCO3 particles. [less ▲]

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See detailProbabilistic Assessment of the Lifetime of Low-Earth-Orbit Spacecraft: Uncertainty Characterization
Dell'Elce, Lamberto ULg; Arnst, Maarten ULg; Kerschen, Gaëtan ULg

in Journal of Guidance Control & Dynamics (2014)

Orbital lifetime estimation is a problem of great timeliness and importance in astrodynamics. In view of the stochastic nature of the thermosphere and of the complexity of drag modeling, any deterministic ... [more ▼]

Orbital lifetime estimation is a problem of great timeliness and importance in astrodynamics. In view of the stochastic nature of the thermosphere and of the complexity of drag modeling, any deterministic assessment of orbital lifetime is likely to be bound to failure. This is why the present paper performs uncertainty quantification of satellite orbital lifetime estimation. Specifically, this paper focuses on the probabilistic characterization of the dominant sources of uncertainty inherent to low-altitude satellites. Uncertainties in the initial state of the satellite and in the atmospheric drag force, as well as uncertainties introduced by modeling limitations associated with atmospheric density models, are considered. Mathematical statistics methods, in conjunction with mechanical modeling considerations, are used to infer the probabilistic characterization of these uncertainties from experimental data and atmospheric density models. This characterization step facilitates the application of uncertainty propagation and sensitivity analysis methods, which in turn allows gaining insight into the impact that these uncertainties have on the orbital lifetime. The proposed developments are illustrated using one CubeSat of the QB50 constellation. [less ▲]

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See detailDe l'analyse des pratiques discursives aux modalités de conception
Joachim, Guillaume ULg; Roosen, Marie ULg; Dondero, Maria Giulia ULg

Conference (2014, May 27)

Cette communication aborde l’étude des interactions entre architectes exploitant différentes ressources (parole, dessin, geste) dans leur pratique professionnelle collaborative de conception. Elle portera ... [more ▼]

Cette communication aborde l’étude des interactions entre architectes exploitant différentes ressources (parole, dessin, geste) dans leur pratique professionnelle collaborative de conception. Elle portera sur des questions méthodologiques, en s’attachant à décrire les apports possibles de travaux de linguistique appliquée à l’analyse de la communication multimodale en architecture. La communication dans les processus de conception est fréquemment abordée à partir de représentations graphiques en tant que procédés de production ou de transmission de connaissances. En effet, c’est en grande partie par le dessin qu’un concepteur donne forme à l’objet qu’il étudie, qu’il le communique à autrui et avant tout qu’il se le représente à lui-même. S’il est avéré que les professionnels de l’architecture utilisent diverses figures comme outils pour représenter et transmettre graphiquement un objet encore inexistant, le champ théorique de la discipline possède par contre peu d’outils méthodologiques permettant de témoigner ou d’analyser minutieusement in vivo la dimension heuristique des échanges entre concepteurs mobilisant plusieurs modalités de communication simultanées. Or, les travaux empiriques de Charles Goodwin (UCLA) inspirés de l’ethnométhodologie et de Lorenza Mondada (UNI Basel) issus de la linguistique appliquée, se sont attachés à l’étude de situations discursives multimodales et ont développé des méthodes découlant de l’analyse conversationnelle. Ces deux approches transdisciplinaires présentent notamment la possibilité aux chercheurs d’analyser à différents niveaux l’articulation de représentations graphiques, gestuelles et verbales et d’identifier la fonction des différentes modalités dans la construction collective du sens et dans l’élaboration d’objets de connaissance propres à une discipline. Nous questionnerons l'intérêt de ces transferts et emprunts d’outils méthodologiques sur l’étude des interactions entre architectes : comment nous aident-ils potentiellement à cerner les procédés par lesquels ces acteurs co-élaborent des objets de savoir utiles pour leur activité ? Quelles contributions inédites produisent-ils pour approcher la cognition dans les processus de conception ? Cette étude expérimentale et réflexive sera enfin l’occasion de décrire brièvement les limites d’une translation des outils de l’analyse interactionnelle située sur l’appréhension des pratiques professionnelles de conception architecturale. [less ▲]

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See detailSynthesis of a glucosamine labeled amphiphilic polymer for drug delivery application
Riva, Raphaël ULg; Boyère, Cédric; Debuigne, Antoine ULg et al

Poster (2014, May 27)

Detailed reference viewed: 20 (1 ULg)