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See detailAn enhanced version of a bone remodelling model based on the continuum damage mechanics theory.
Mengoni, Marlène ULg; Ponthot, Jean-Philippe ULg

in Computer Methods in Biomechanics & Biomedical Engineering (2015), 18(12), 1367-1376

The purpose of this work is to propose an enhancement of Doblaré and García's internal bone remodelling model based on the continuum damage mechanics theory. In their paper, they stated that the evolution ... [more ▼]

The purpose of this work is to propose an enhancement of Doblaré and García's internal bone remodelling model based on the continuum damage mechanics theory. In their paper, they stated that the evolution of the internal variables of the bone microstructure, and its incidence on the modification of the elastic constitutive parameters, may be formulated following the principles of Continuum Damage Mechanics, although no actual damage was considered. The resorption and apposition criteria (similar to the damage criterion) were expressed in terms of a mechanical stimulus. However, the resorption criterion is lacking a dimensional consistency with the remodelling rate. We here propose an enhancement to this resorption criterion, insuring the dimensional consistency while retaining the physical properties of the original remodelling model. We then analyse the change in the resorption criterion hypersurface in the stress space for a 2D analysis. We finally apply the new formulation to analyse the structural evolution of a 2D femur. This analysis gives results consistent with the original model but with a faster and more stable convergence rate. [less ▲]

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See detailThe materiality of Intangible Cultural Heritage: food and social encounters.
Mescoli, Elsa ULg

Conference (2015, September)

Following the patrimonialization process of the Mediterranean diet, some gastronomies found themselves involved within a common framework of food traditions. Some regional practices, indicated as ... [more ▼]

Following the patrimonialization process of the Mediterranean diet, some gastronomies found themselves involved within a common framework of food traditions. Some regional practices, indicated as representative of national food cultures, were chosen to illustrate a shared heritage that historically took a shape around the Mediterranean sea. This heritage, still concretely performed, needed to be stated and preserved against the globalization of food practices. Institutional and political dynamics, occurring on a transnational level, triggered this process, which is nevertheless not detached from the communities involved. Common people played a fundamental role not only in promoting the patrimonialization process itself, but above all in concretely perpetuating some traditions and in spreading them in the contemporary world. In particular, some different cultural groups that found themselves living a common territory and social context thanks to migration, began dialoguing about their own food traditions, starting from some shared elements. As a consequence, some gastronomies interact through people’s practices and define in relation one to the other. This is the case, among others, of Moroccan and Italian cuisine. Throughout a doctoral research conducted within a group of Moroccan women living in the North of Italy, I collected an amount of ethnographic materials showing how social encounters developed through food. The influence of the patrimonialization process on these encounters made people try to find similarities among different traditional practices or to describe some ways of reinterpreting them in reason of the new context. My presentation will focus on these dynamics, thus proving that the Intangible Cultural Heritage is indeed grounded on materiality, that is, in this case, the concrete performance of food practices and their pragmatic effects on relations among humans. [less ▲]

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See detailRorschach et théorie de l’art : Le sublime et le formel
Englebert, Jérôme ULg; Sass, Louis

Conference (2015, August 28)

À côté de l’énorme travail de standardisation réalisé par Exner, l’un des éléments d’avenir qui devrait mobiliser la recherche sur le test de Rorschach concerne la signification psychologique des ... [more ▼]

À côté de l’énorme travail de standardisation réalisé par Exner, l’un des éléments d’avenir qui devrait mobiliser la recherche sur le test de Rorschach concerne la signification psychologique des variables. En effet, le Comprehensive System fournit une solide base empirique offrant une validité et une fidélité de bonne qualité. En revanche, l’étude et la discussion des corrélats psychologiques des différentes cotations et de leurs interprétations demeure un champ de recherche où de nombreuses hypothèses et réflexions sont encore à formuler. Dans ce contexte, nous souhaitons proposer une hypothèse originale qui prendra ses racines dans l’esthétique (Schiller, Burke), la littérature (Stendhal), la philosophie de l’art (Kant) et la philosophie existentielle (Heidegger). Nous proposons d’introduire la notion de « sublime », qui est à différencier du « beau », pour discuter de l’interprétation des Vista (V) et de la Form Dimension (FD). Le sublime suggérerait une submersion des facultés cognitives, voire un état de dépassement, en contraste avec la clarté de la beauté circonscrite dans un espace et totalement sous le contrôle cognitif du sujet. Notre réflexion nous mènera à discuter des liens entre perception et angoisse et de la différence qu’il y a à faire entre cette émotion et la peur. Nous évoquerons pour conclure les dimensions adaptatives des réponses Vista et FD reflétant, selon Rorschach (1921) et Exner (2003) et sans doute à raison, des formes variées du mécanisme d’introspection. [less ▲]

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See detailExploring the schizophrenic hyperreflexivity on the Rorschach test
Englebert, Jérôme ULg; Bataille, Jennifer; Mormont, Christian ULg et al

Poster (2015, August 28)

L’hyper-réflexivité schizophrénique peut être définie comme une attitude particulière de la conscience consistant à interroger de façon explicite et réflexive des phénomènes généralement implicites et ... [more ▼]

L’hyper-réflexivité schizophrénique peut être définie comme une attitude particulière de la conscience consistant à interroger de façon explicite et réflexive des phénomènes généralement implicites et préréflexifs (Sass, 2014). Notre hypothèse est que ce mécanisme se manifeste dans les protocoles du test de Rorschach des sujets schizophrènes (Englebert, 2013). Pour l’éprouver, nous avons administré le test à douze sujets schizophrènes. L’originalité de cette recherche repose sur une seconde présentation des planches (trois jours plus tard) qui a permis d’évoquer avec les sujets la permanence de leurs perceptions et de discuter de l’acception commune de celles-ci (pensez-vous que la plupart des autres personnes pourrait voir ce que vous voyez ?). Les résultats confirment notre hypothèse, tant au niveau quantitatif (les marqueurs de l’hyper-réflexivité que nous avions identifiés se retrouvent dans la majorité des protocoles) que qualitatif (phrases suggérant une interrogation épistémologique du test, par exemple). Enfin, nous remarquerons que l’attitude schizophrénique envers le test de Rorschach est assez subtile puisqu’elle identifie le fondement épistémologique du test reposant sur la nécessité d’une fausse perception – une « violation de la réalité » selon Exner (2003). Les sujets schizophrènes mettent en évidence la règle implicite sur laquelle repose le test qui consiste à ne pas donner la seule véritable bonne réponse (systématique) au test qui est « une tache ». [less ▲]

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See detailA Rorschach study of the borderline personality
Englebert, Jérôme ULg; Rommes, Jennifer; Mormont, Christian ULg et al

Conference (2015, August 28)

Nous étudions les manifestations psychologiques au test de Rorschach de sujets présentant un diagnostic de trouble de la personnalité borderline. Dans la continuité des études de Mormont (1969) et Mihura ... [more ▼]

Nous étudions les manifestations psychologiques au test de Rorschach de sujets présentant un diagnostic de trouble de la personnalité borderline. Dans la continuité des études de Mormont (1969) et Mihura (2006), nous avons administré le test à 15 sujets selon les recommandations du Système Intégré. Nos résultats indiquent les tendances spécifiques suivantes : une affectivité qui tend à être extratensive ou ambiéquale (86,7% des sujets), une proportion élevée de réponses couleur/forme (80%), un nombre élevé d’abstractions (66,7%), un nombre important de réponses « agressives » (80%) et « morbides » (86,7%). Une altération variable du testing de la réalité apparait pour chaque protocole. Notons la présence importante (80%) de références personnelles (PER). Signalons également la présence constante de termes particuliers dans le verbatim : énonciation de la couleur rouge (sang, amour), caractère dysphorique de certaines réponses (monstrueux, diabolique), ainsi que des perceptions duales (le bien/le mal). En conclusion, notre étude suggère que le Rorschach en Système Intégré, repérant en première approche des éléments psychologiques que l'on peut raisonnablement mettre en rapport avec la sémiologie clinique et la théorie des personnalités borderlines, l'approfondissement de la recherche peut laisser espérer une meilleure compréhension de ce trouble complexe. [less ▲]

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See detailBiotechnological potential of novel bacterial strains isolated on the brown alga Ascophyllum nodosum
Martin, Marjolaine ULg; Martin, Renée ULg; Barbeyron, Tristan et al

Conference (2015, August 18)

Bacteria associated with algae are underexplored despite their huge biodiversity and the fact that they differ markedly from those living freely in seawater. These bacterial communities are known to ... [more ▼]

Bacteria associated with algae are underexplored despite their huge biodiversity and the fact that they differ markedly from those living freely in seawater. These bacterial communities are known to represent great potential for the production of diverse bioactive compounds, such as specific glycoside hydrolases, as they interact in multiple complex ways with their host. Furthermore, enzymes from marine bacteria have original properties, like cold-adapted, halotolerant and highly stable, which are constantly searched out by bio-industries. The aim of our study was to identify bacteria, associated with the brown alga Ascophyllum nodosum, showing diverse polysaccharolytic activities. To isolate cultivable microorganisms, algal thalli of Ascophyllum nodosum were swabbed with sterile cotton tips and marine agar plates were inoculated. Three-hundred isolated bacteria were screened for agarase, kappa- and iota-carrageenase, and sulfatase activities on specific marine media. Thirty-two bacteria with polysaccharolytic activities were isolated and a part of their 16S rDNA (8F-1492R) were amplified and sequenced. Twenty-seven were classified as Flavobacteriia and five as Gammaproteobacteria. Putative new strains and species of Zobellia, Maribacter, Cellulophaga, Shewanella, Glaciecola, Pseudoalteromonas and Colwellia were identified by phylogenetic analysis. All those genera are well-known to colonize algal surface but only some of them are famous to degrade algal polysaccharides (Zobellia, Maribacter, Cellulophaga, and Pseudoalteromonas). However, all those novel bacterial strains/species showed multiple and diverse enzymatic activities (agarase, iota-and kappa-carrageenase, cellulase, beta-glucosidase, sulfatase and/or amylase activities). Genomics libraries with their DNA were constructed in Escherichia coli and Bacillus subtilis and are screened to identify the genes coding for the observed enzymatic activities. Those novel glycoside hydrolases from unknown marine bacteria should have original and innovative properties with great biotechnological potential. [less ▲]

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See detailAtmospheric metal pollution over the last 250 years inferred from speleothem geochemistry
Allan, Mohammed ULg; Fagel, Nathalie ULg; verheyden, sophie

Conference (2015, August 17)

Lead concentrations and isotope ratios from two speleothems from the Han-sur-Lesse cave in southern Belgium were measured in order to study the ability of speleothems to act as archives of atmospheric ... [more ▼]

Lead concentrations and isotope ratios from two speleothems from the Han-sur-Lesse cave in southern Belgium were measured in order to study the ability of speleothems to act as archives of atmospheric pollution. To address this aim we analyzed trace elemental Al and Pb compositions by LA-ICP-MS and ICP-MS as well as Pb isotopes by MC-ICP-MS. The results help to identify three Pb-enriched intervals: from 1880 to 1905 AD, from 1945 to 1965 AD, and from 1975 to 1990 AD. The speleothem record is consistent with the evolution of atmospheric pollution in Belgium. Lead isotope ratios confirm that coal and gasoline combustion, combined with regional metallurgical activities, were the predominant Pb pollution sources in the stalagmites during the last 250 years. This research underscores the importance of speleothems as a valuable tool for the discrimination between anthropogenic and natural lead contributions in the environment and consequently for quantifying the anthropogenic contribution or determining natural background values in continental settings. [less ▲]

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See detailPerformance, robustness and sensitivity analysis of the nonlinear tuned vibration absorber
Detroux, Thibaut ULg; Habib, Giuseppe ULg; Masset, Luc ULg et al

in Mechanical Systems & Signal Processing (2015), 60-61

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of ... [more ▼]

The nonlinear tuned vibration absorber (NLTVA) is a recently developed nonlinear absorber which generalizes Den Hartog׳s equal peak method to nonlinear systems. If the purposeful introduction of nonlinearity can enhance system performance, it can also give rise to adverse dynamical phenomena, including detached resonance curves and quasiperiodic regimes of motion. Through the combination of numerical continuation of periodic solutions, bifurcation detection and tracking, and global analysis, the present study identifies boundaries in the NLTVA parameter space delimiting safe, unsafe and unacceptable operations. The sensitivity of these boundaries to uncertainty in the NLTVA parameters is also investigated. [less ▲]

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See detailPhysical modeling of lateral dike breaching due to overtopping
Rifai, Ismail; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in River, Coastal and Estuarine Morphodynamics, RCEM 2015 (2015, August)

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures ... [more ▼]

Dikes are commonly used as defense structures for river flow channelization, protecting population and property from floods and against lateral riverbed migration. However, the aging of these structures, combined with their increased vulnerability to extreme hydrological events may cause the dikes to breach, and subsequently to break. Furthermore, statistics show that flow overtopping is the main cause of dike failure, which emphasizes the need to understand thoroughly the process of breaching. Indeed, from a risk management perspective it is particularly important to have a detailed understanding of the mechanisms (e.g. internal erosion, overtopping erosion) underlying the formation of breaches due to overtopping and reliable information on flows passing through them. Conversely, the current knowledge of breaching mechanisms remains fragmented, especially because dike failure involves complex interactions between flows, materials of the structure, soil and foundations. The existing studies have addressed partially these interactions as the considered idealized dikes were generally homogenous, the piping erosion unaccounted for and the overtopping replicated in a dam-break like configuration. Yet, river embankments are subjected to high flow velocities parallel to the direction of the dike and to flow in the floodplain, which highly influence the shape of the breach and its evolution. The objective of the present work is to fill this gap. A laboratory experimental investigation is planned in the National Laboratory for Hydraulics and Environment (LNHE) of EDF R&D (France) and in the research group Hydraulics in Environmental and Civil Engineering (HECE) of the University of Liege (Belgium), reproducing realistic configurations of river dikes, accounting for the tangential flow in both main channel and floodplain. It enables thus the assessment of, on the one hand, the effect of the increase of the water level, and on the other hand, the influence of waves. The laboratory tests also consider the effect of a surface layer and composition of the dike core by testing different material mixtures. Geometry and composition of the idealized dikes are representative of typical field dikes, based on the similarity theory. [less ▲]

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See detailA study of composite laminates failure using an anisotropic gradient-enhanced damage mean-field homogenization model
Wu, Ling ULg; Sket, Federico; Molina-Aldareguia, Jon M et al

in Composite Structures (2015), 126

The failure of carbon fiber reinforced epoxy laminates is studied using an anisotropic gradient-enhanced continuum damage model embedded in a mean-field homogenization scheme. In each ply, a homogenized ... [more ▼]

The failure of carbon fiber reinforced epoxy laminates is studied using an anisotropic gradient-enhanced continuum damage model embedded in a mean-field homogenization scheme. In each ply, a homogenized material law is used to capture the intra-laminar failure. The anisotropy of the homogenized material model results from the homogenization method and from the reformulation of the non-local continuum damage theory to account for the material anisotropy. As a result the damage propagation direction in each ply is predicted with accuracy as compared to the experimental results, while the problems of losing uniqueness and strain localization, which occur in classical finite element simulations when strain softening of materials is involved, can be avoided. To model the delamination process, the hybrid discontinuous Galerkin/extrinsic cohesive law method is introduced at the ply interfaces. This hybrid method avoids the need to propagate topological changes in the mesh with the propagation of the delamination while it preserves the consistency and stability in the un-cracked interfaces. As a demonstration, open-hole coupons with different stacking sequences are studied numerically and experimentally. Both the intra- and inter-laminar failure patterns are shown to be well captured by the computational framework. [less ▲]

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See detailCharacterizing activity sequences using Profile Hidden Markov Models
Liu, Feng; Janssens, Davy; Cui, JianXun et al

in Expert Systems with Applications (2015), 42(13), 57055722

In literature, activity sequences, generated from activity-travel diaries, have been analyzed and classified into clusters based on the composition and ordering of the activities using Sequence Alignment ... [more ▼]

In literature, activity sequences, generated from activity-travel diaries, have been analyzed and classified into clusters based on the composition and ordering of the activities using Sequence Alignment Methods (SAM). However, using these methods, only the frequent activities in each cluster are extracted and qualitatively described; the infrequent activities and their related travel episodes are disregarded. Thus, to quantify the occurrence probabilities of all the daily activities as well as their sequential orders, we develop a novel process to build multiple alignments of the sequences and subsequently derive profile Hidden Markov Models (pHMMs). This process consists of 4 major steps. First, activity sequences are clustered based on a pre-defined scheme. The frequent activities along with their sequential orders are then identified in each cluster, and they are subsequently used as a template to guide the construction of a multiple alignment of the cluster of sequences. Finally, a pHMM is employed to convert the multiple alignment into a position-specific scoring system, representing the probability of each frequent activity at each important position of the alignment as well as the probabilities of both insertion and deletion of infrequent activities. By applying the derived pHMMs to a set of activity-travel diaries collected in Belgium as well as a group of mobile phone call location data recorded in Switzerland, the potential and effectiveness of the models in capturing the sequential features of each cluster and distinguishing them from those of other clusters, are demonstrated. The proposed method can also be utilized to improve activity-based transportation model validation and travel survey designs. Furthermore, it offers a wide application in characterizing a group of any related sequences, particularly sequences varying in length and with a high frequency of short sequences that are typically present in human behavior. [less ▲]

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See detailSedimentological and geochemical evidence to detect arid periods recorded in wadi deposits: a case study from northern Morocco
El Ouahabi, Meriam ULg; Bartz, Melanie; Rixhon, Gilles et al

Poster (2015, July 27)

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See detailIdentification of VZV ORF9p potential cellular partners that could be important for the viral egress.
Lebrun, Marielle ULg; riva, laura; Rambout, Xavier ULg et al

Poster (2015, July 26)

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate ... [more ▼]

ORF9p (homologous to HSV-1 VP22) is a VZV tegument protein essential for the viral replication. During the lytic cycle it is the mostly expressed gene. We have recently demonstrated that it is a substrate of the viral kinase ORF47p and that its ORF47p-dependent phosphorylation is important for the secondary envelopment process. We also have identified an acidic cluster (AC) within the protein that is important for its correct localization in the infected cells and for the interaction with ORF47p. The recombinant VZV expressing ORF9p-ΔAC presents an accumulation of capsids in the perinuclear space. ORF9p seems then to play an important role in several steps of the egress process. In this context, we sought to identify cellular partners of ORF9p that might be important for these functions. We performed a yeast two hybrid screen against the human ORFeome 5.1. and picked out 44 candidates among which 5 proteins playing roles in membrane organization and targeting. We currently are trying to confirm these interactions in infected cells and to assess the role of these interactions for the viral lytic cycle. [less ▲]

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See detailPersonnalité antisociale et psychopathologie
Englebert, Jérôme ULg

Conference (2015, July 14)

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes ... [more ▼]

Notre communication a pour objectif de confronter les critères de la personnalité antisociale du DSM-IV et du DSM-5 à une réflexion psychopathologique. Nous commencerons par une analyse des différentes contradictions propres au diagnostic qui nous mèneront à l’identification du critère « primaire » de cette entité qui est l’« incapacité à se conformer aux lois et normes sociales ». Nous confronterons ensuite à des situations cliniques l’hétérogénéité des profils pouvant répondre à ce diagnostic. Nos constats nous conduiront à mettre en doute la validité apparente du concept de personnalité antisociale, puisqu’il recouvre des modes de fonctionnement psychologique variés. La valeur discriminative faible, en matière de fonctionnement psychologique, suggère que c’est une dimension autre que psychopathologique qui organise ce diagnostic. Dénuée de toute attention pour les modes d’interactions, pour le vécu émotionnel et pour les états de subjectivité, la notion de personnalité antisociale ne porte pas d’intérêt à l’individu qu’elle catégorise, mais bien à l’acte délinquant commis par ce dernier. Nous conclurons sur le constat de l’absence de dimension psychopathologique de la personnalité antisociale, qui se révèle être un diagnostic principalement criminologique, à l’inverse des fondements de l’éthique psychopathologique. [less ▲]

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See detailDevelopment, validation and comparison of NIR and Raman methods for the identification and assay of poor-quality oral quinine drops.
Mbinze Kidenge, Jérémie; Sacre, Pierre-Yves ULg; Yemoa, Achille et al

in Journal of Pharmaceutical & Biomedical Analysis (2015), 111

Poor quality antimalarial drugs are one of the public’s major health problems in Africa. The depth of this problem may be explained in part by the lack of effective enforcement and the lack of efficient ... [more ▼]

Poor quality antimalarial drugs are one of the public’s major health problems in Africa. The depth of this problem may be explained in part by the lack of effective enforcement and the lack of efficient local drug analysis laboratories. To tackle part of this issue, two spectroscopic methods with the ability to detect and to quantify quinine dihydrochloride in children’s oral drops formulations were developed and validated. Raman and Near Infrared (NIR) spectroscopy were selected for the drug analysis due to their low cost, non-destructive and rapid characteristics. Both of the methods developed were successfully validated using the total error approach in the range of 50-150% of the target concentration (20% W/V) within the 10% acceptance limits. Samples collected on the Congolese pharmaceutical market were analyzed by both techniques to detect potentially substandard drugs. After a comparison of the analytical performance of both methods, it has been decided to implement the method based on NIR spectroscopy to perform the routine analysis of quinine oral drop samples in the Quality Control Laboratory of Drugs at the University of Kinshasa (DRC). [less ▲]

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See detailDrug loading of polymer implants by supercritical CO2 assisted impregnation: a review
Champeau, Mathilde; Thomassin, Jean-Michel ULg; Tassaing, Thierry et al

in Journal of Controlled Release (2015), 209

Drug loaded implants also called drug-eluting implants have proven their benefits over simple implants. Among the developed manufacturing processes, the supercritical CO2 (scCO2) assisted impregnation has ... [more ▼]

Drug loaded implants also called drug-eluting implants have proven their benefits over simple implants. Among the developed manufacturing processes, the supercritical CO2 (scCO2) assisted impregnation has attracted growing attention to load Active Pharmaceutical Ingredients into polymer implants since it enables to recover a final implant free of any solvent residue and to operate under mild temperature which is suitable for processing with thermosensitive drugs. This paper is a review of the state-of-the-art and the application of the scCO2 assisted impregnation process to prepare drug-eluting implants. It introduces the process and presents its advantages for biomedical applications. The influences of the characteristics of the implied binary systems and of the experimental conditions on the drug loading are described. Then, the various current applications of this process for manufacturing drug-eluting implants are reviewed. Finally, the new emerging variations of this process are described. [less ▲]

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See detailMalentendu visuel et folie : Test de Rorschach et hyper-conscience
Englebert, Jérôme ULg

Conference (2015, July 02)

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