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See detailImpacts of climate change on future flood damage on the river Meuse, with a distributed uncertainty analysis
Detrembleur, Sylvain; Stilmant, Frédéric ULg; Dewals, Benjamin ULg et al

in Natural Hazards (2015), 77(3), 1533-1549

Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of ... [more ▼]

Flood-risk assessments are an objective and quantitative basis for implementing harmonized flood mitigation policies at the basin scale. However, the generated results are subject to different sources of uncertainty arising from underlying assumptions, data availability and the random nature of the phenomenon. These sources of uncertainty are likely to bias conclusions because they are irregularly distributed in space. Therefore, this paper addresses the question of the influence of local features on the expected annual damage in different municipalities. Based on results generated in the frame of a transnational flood-risk-assessment project for the river Meuse (Western Europe) taking climate change into account, the paper presents an analysis of the relative contributions of different sources of uncertainty within one single administrative region (the Walloon region in Belgium, i.e. a river reach of approximately 150 km). The main sources of uncertainty are not only found to vary both from one municipality to the other and in time, but also to induce opposite effects on the computed damage. Nevertheless, practical conclusions for policy-makers can still be drawn. [less ▲]

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See detailDynamique et structure de la haute atmosphère de Mars
Stiepen, Arnaud ULg

Book published by Edition Européenne Universitaire (2015)

La haute atmosphère de Mars est une région clé pour notre compréhension de son évolution. Par analogie, l'étude de Mars permettra de mieux cerner les grands changements climatiques terrestres. Depuis 2003 ... [more ▼]

La haute atmosphère de Mars est une région clé pour notre compréhension de son évolution. Par analogie, l'étude de Mars permettra de mieux cerner les grands changements climatiques terrestres. Depuis 2003, la sonde Mars Express de l'ESA observe la thermosphère de Mars par le biais des traceurs de sa composition, structure et dynamique que sont les luminescences atmosphériques. Cette étude se concentre sur l'observation ultraviolette de la haute atmosphère de Mars et propose des résultats inédits concernant ses propriétés. Cet ouvrage lance aussi des pistes pour de futures observations grâce à la sonde MAVEN de la NASA. [less ▲]

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See detailThe Geoarchaeology of Utica, Tunisia: The Paleogeography of the Mejerda Delta and Hypotheses Concerning the Location of the Ancient Harbor
Delile, Hugo; Abichou; Gadhoum, Ahmed et al

in Geoarchaeology (2015), 30(4), 291-306

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See detailLong-term XMM-Newton investigation of two particle-accelerating colliding-wind binaries in NGC6604: HD168112 and HD167971
De Becker, Michaël ULg

in Monthly Notices of the Royal Astronomical Society (2015), 451(1), 5589-5599

The long-term (over more than one decade) X-ray emission from two massive stellar systems known to be particle accelerators is investigated using XMM-Newton. Their X-ray properties are interpreted taking ... [more ▼]

The long-term (over more than one decade) X-ray emission from two massive stellar systems known to be particle accelerators is investigated using XMM-Newton. Their X-ray properties are interpreted taking into account recent information about their multiplicity and orbital parameters. The two targets, HD168112 and HD167971 appear to be overluminous in X-rays, lending additional support to the idea that a significant contribution of the X-ray emission comes from colliding-wind regions. The variability of the X-ray flux from HD168112 is interpreted in terms of varying separation expected to follow the 1/D rule for adiabatic shocked winds. For HD167971, marginal decrease of the X-ray flux in September 2002 could tentatively be explained by a partial wind eclipse in the close pair. No long-term variability could be demonstrated despite the significant difference of separation between 2002 and 2014. This suggests the colliding-wind region in the wide orbit does not contribute a lot to the total X-ray emission, with a main contribution coming from the radiative shocked winds in the eclipsing pair. The later result provides evidence that shocks in a colliding-wind region may be efficient particle accelerators even in the absence of bright X-ray emission, suggesting particle acceleration may operate in a wide range of conditions. Finally, in hierarchical triple O-type systems, thermal X-rays do not necessarily constitute an efficient tracer to detect the wind-wind interaction in the long period orbit. [less ▲]

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See detailSelective top-down control of epiphytic biomass by amphipods from Posidonia oceanica meadows: implications for ecosystem functioning
Michel, Loïc ULg; Dauby, Patrick ULg; Dupont, Alessandra et al

in Belgian Journal of Zoology (2015), 145(2), 83-93

Mediterranean Posidonia oceanica meadows shelter an important biomass and biodiversity of amphipod crustaceans that graze on epiphytes. However, their actual significance for ecosystem functional ... [more ▼]

Mediterranean Posidonia oceanica meadows shelter an important biomass and biodiversity of amphipod crustaceans that graze on epiphytes. However, their actual significance for ecosystem functional processes is hard to estimate, due to the lack of adequate data. Here, a field microcosm-based inclusion experiment was used to test if three of the dominant taxa of the amphipod community (Apherusa chiereghinii, Dexamine spiniventris and Gammarus spp.) could exert top-down control on seagrass leaf epiphytes. Influence of amphipod activity on nutrient availability for the host species was also investigated. All grazer taxa significantly reduced biomasses of erect macroalgae and erect sessile animals present on leaves. None of them consumed encrusting epiflora or epifauna. This selective top-down control could have important implications for the structure of the epiphytic community of P. oceanica leaves, which is one of the most diverse and abundant of all seagrass species. Grazing activity of all taxa caused higher N content of seagrass leaves, likely through amphipod excretion and/or sloppy feeding. Since P. oceanica meadows often grow in oligotrophic zones where plant growth can be nutrient-limited, this N enrichment could enhance seagrass production. Overall, the ecological interaction between P. oceanica and amphipods could be seen as a facultative mutualistic relationship. Our results suggest that amphipod mesograzers are key-elements in some of the functional processes regulating these complex and yet endangered ecosystems, which are essential components of Mediterranean coastal zones. [less ▲]

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See detailL'éveil de la matrix-gla-protéine sonnera le glas des calcifications vasculaires
DELANAYE, Pierre ULg; Liabeuf, Sophie; BOUQUEGNEAU, Antoine ULg et al

in Néphrologie & Thérapeutique (2015), 11(4), 191-200

La matrix-gla-protéine (MGP) est principalement sécrétée par les chondrocytes et les cellules musculaires lisses des parois vasculaires. Son rôle est d’inhiber localement le développement des ... [more ▼]

La matrix-gla-protéine (MGP) est principalement sécrétée par les chondrocytes et les cellules musculaires lisses des parois vasculaires. Son rôle est d’inhiber localement le développement des calcifications vasculaires. MGP doit bénéficier de deux processus post-transcriptionnels avant d’être pleinement active : une phosphorylation de résidus sérine et une carboxylation de résidus glutamate. Cette carboxylation ne peut se faire qu’en présence de quantité suffisante de vitamine K. Plusieurs formes de MGP circulent donc dans le plasma, certaines étant totalement inactives (la MGP déphosphorylée et décarboxylée), d’autres possédant une activité biologique variable en fonction du nombre de sites carboxylés ou phosphorylés. Il existe un lien théorique étroit entre MGP, vitamine K, calcifications vasculaires et maladies cardiovasculaires et ce, particulièrement chez les patients souffrant d’insuffisance rénale chronique, a fortiori s’ils sont dialysés. Si l’existence de ce lien a été démontrée via de nombreuses et solides données fondamentales, les données cliniques restent, à ce jour, observationnelles et doivent donc être interprétées avec prudence. Mesurer une fraction de MGP dans le plasma pour estimer le degré de calcification d’un patient donné n’est pas encore d’actualité . La forme inactive pourrait être utile pour juger des réserves en vitamine K au niveau vasculaire. Dans cet article de revue, nous reviendrons sur les bases théoriques du rôle de MGP dans le processus de calcification vasculaire, sur le défi analytique que représente sa détermination dans le plasma, ainsi que sur les liens entre MGP, vitamine K et calcifications vasculaires en population géne´ rale et chez les patients insuffisants rénaux. [less ▲]

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See detailSpectroscopic survey of Kepler stars. I. HERMES/Mercator observations of A- and F-type stars
Niemczura, E.; Murphy, S. J.; Smalley, B. et al

in Monthly Notices of the Royal Astronomical Society (2015), 450

The Kepler space mission provided near-continuous and high-precision photometry of about 207,000 stars, which can be used for asteroseismology. However, for successful seismic modelling it is equally ... [more ▼]

The Kepler space mission provided near-continuous and high-precision photometry of about 207,000 stars, which can be used for asteroseismology. However, for successful seismic modelling it is equally important to have accurate stellar physical parameters. Therefore, supplementary ground-based data are needed. We report the results of the analysis of high-resolution spectroscopic data of A- and F-type stars from the Kepler field, which were obtained with the HERMES spectrograph on the Mercator telescope. We determined spectral types, atmospheric parameters and chemical abundances for a sample of 117 stars. Hydrogen Balmer, Fe I, and Fe II lines were used to derive effective temperatures, surface gravities, and microturbulent velocities. We determined chemical abundances and projected rotational velocities using a spectrum synthesis technique. The atmospheric parameters obtained were compared with those from the Kepler Input Catalogue (KIC), confirming that the KIC effective temperatures are underestimated for A stars. Effective temperatures calculated by spectral energy distribution fitting are in good agreement with those determined from the spectral line analysis. The analysed sample comprises stars with approximately solar chemical abundances, as well as chemically peculiar stars of the Am, Ap, and Lambda Boo types. The distribution of the projected rotational velocity, Vsini, is typical for A and F stars and ranges from 8 to about 280 km/s, with a mean of 134 km/s. [less ▲]

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See detailComparison of fracture prediction models on sheet metal blanking simulations
Canales Cardenas, Cristian ULg; Boman, Romain ULg; Bussetta et al

Conference (2015, July)

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See detailReinforcement Learning of Heuristic EV Fleet Charging in a Day-Ahead Electricity Market
Vandael, Stijn; Claessens, Bert; Ernst, Damien ULg et al

in IEEE Transactions on Smart Grid (2015), 6(4), 1795-1805

This paper addresses the problem of defining a day-ahead consumption plan for charging a fleet of electric vehicles (EVs), and following this plan during operation. A challenge herein is the beforehand ... [more ▼]

This paper addresses the problem of defining a day-ahead consumption plan for charging a fleet of electric vehicles (EVs), and following this plan during operation. A challenge herein is the beforehand unknown charging flexibility of EVs, which depends on numerous details about each EV (e.g., plug-in times, power limitations, battery size, power curve, etc.). To cope with this challenge, EV charging is controlled during opertion by a heuristic scheme, and the resulting charging behavior of the EV fleet is learned by using batch mode reinforcement learning. Based on this learned behavior, a cost-effective day-ahead consumption plan can be defined. In simulation experiments, our approach is benchmarked against a multistage stochastic programming solution, which uses an exact model of each EVs charging flexibility. Results show that our approach is able to find a day-ahead consumption plan with comparable quality to the benchmark solution, without requiring an exact day-ahead model of each EVs charging flexibility. [less ▲]

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See detailLate Holocene history of the Fuji Five Lakes (Japan)
Lamair, Laura ULg; Hubert, Aurelia ULg; Boes, Evelien et al

Conference (2015, July)

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See detailWe forgot to pay attention to ordinary tourism! A call to revise the research agenda for rural tourism
Schmitz, Serge ULg; Crozat, Dominique

in Firmino, Ana (Ed.) Book of Abstracts and Programme: 23rd Annual Colloquium on Sustainable Rural Systems: Smart Answers for a smiling future (2015, July)

This paper aims to suggest a new research agenda for rural tourism, including for a smiling future for the countryside, in reversing the current trend to distinguish the destination, to aim at ... [more ▼]

This paper aims to suggest a new research agenda for rural tourism, including for a smiling future for the countryside, in reversing the current trend to distinguish the destination, to aim at supersegmentation of tourism and to target a cultural, elitist, tourism. Indeed most tourist activities can be done and are done in a relative vicinity, by ordinary tourists aiming to have a good time. Moreover, the countryside does not always offer extraordinary sights that attract people from the whole continent. We argue that there should be a place and more attention for ordinary tourism development. By ordinary tourism, we do not mean mass tourism but just the fact that some people spent a few days away from home. We do not want to reject the appealing concepts of cultural tourism, ecotourism, adventure tourism, ethnic tourism, gastronomic tourism, farm tourism and so on. We just want to be realistic and call to rethink the importance of ordinary tourism and its current challenges: facing new ways of traveling (e.g. Low cost), of buying vacation (e-commerce), of enjoying holidays (more frequently/with friends, alone or with the family/ being active or passive). [less ▲]

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See detailHybrid processing of SCADA and synchronized phasor measurements for tracking network state
Alcaide-Moreno, Boris; Fuerte-Esquivel, Claudio; Glavic, Mevludin ULg et al

in Proc. IEEE PES General Meeting (2015, July)

This paper proposes a new tracking state estimator aimed at following some of the dynamics of the network state (bus voltage phasors) by a hybrid processing of SCADA and synchronized phasor measurements ... [more ▼]

This paper proposes a new tracking state estimator aimed at following some of the dynamics of the network state (bus voltage phasors) by a hybrid processing of SCADA and synchronized phasor measurements. The latter are assumed to be available in limited number. To avoid time skew effects, only the SCADA measurements received since the last execution of the estimator are processed. To ensure observability, estimated SCADA measurements are used as pseudo-measurements. The procedure includes a prediction, an innovation analysis and a correction step. The latter consists of solving a constrained least-squares optimization. The simulation results refer to a test system undergoing large disturbances, evolving to long-term voltage instability or stabilized by emergency control. The proposed method appears to satisfactorily track the overall network evolution, even during those severe conditions. [less ▲]

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See detailBilevel optimization in the context of intermodal pricing: state of art
Tawfik, Christine Maher Fouad ULg; Limbourg, Sabine ULg

Scientific conference (2015, July)

With the rising interest to stimulate intermodal transport, determining pricing strategies can be intrinsically challenging. We provide a review on the current state of research in intermodal pricing ... [more ▼]

With the rising interest to stimulate intermodal transport, determining pricing strategies can be intrinsically challenging. We provide a review on the current state of research in intermodal pricing, through which we identify a peculiar gap in optimization approaches. A suggestion to exploit the bilevel optimization technique is presented, as well as an account of its widely successful application to price setting problems. The different approaches to express the network users’ behavior, regarded as the lower level problem, are highlighted together with the particular modeling aspects of intermodal networks. [less ▲]

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See detailMedieval Francophone Literary Culture Outside France database
Morato, Nicola ULg; Gaunt, Simon; Gilbert, Jane et al

Textual, factual or bibliographical database (2015)

The database is the major output of the project Medieval Francophone Literary Culture Outside France (an Art and Humanities Research Council project). It contains descriptions of more than 90% of the ... [more ▼]

The database is the major output of the project Medieval Francophone Literary Culture Outside France (an Art and Humanities Research Council project). It contains descriptions of more than 90% of the manuscript witnesses of Prose Lancelot, Prose Tristan, Guiron le Courtois, Roman de Troie, Roman de Alexandre, Histoire Ancienne jusqu'à César. [less ▲]

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See detailThe French language runs throughout the world
Morato, Nicola ULg; Gaunt, Simon

E-print/Working paper (2015)

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See detailDevelopping competencies of public managers: a hybrid system analysis in a critical management education perspective
Göransson, Marie; Rondeaux, Giseline ULg

Conference (2015, July)

The role and competencies of public managers are a central topic of public administration reforms implemented these last 30 years in OECD countries. In fact, as New Public Management (NPM) doctrines ... [more ▼]

The role and competencies of public managers are a central topic of public administration reforms implemented these last 30 years in OECD countries. In fact, as New Public Management (NPM) doctrines suggest, public administration managers have to be professionalized and free to manage (Minogue, Hulme & Polidano, 1998). This professionalization and managerial freedom imply the development of new competencies borrowed from the private sector. This leads public managers to be focused on the search for performance and to consider citizens as clients. Without losing its dominance, the NPM conception has evolved with the development of new theoretical paradigms such as Neo-Weberian State (Pollitt & Bouckaert, 2004 ; Peters, 2001 ; Drechsler, 2005) and Public Value Management (Stoker, 2006 ; Moore, 1995). In these models, the manager is still driven by performance targets to provide citizen-customers professional and quality service. However, these paradigms reassert the centrality of the State and the specificity of the public sector by comparison with the private sector. In addition, the public manager must play a role in the co-construction of public value for citizens and political actor in both the short and long term (Greve, 2010). These evolutions have led to a need for hiring public managers with new profiles, and this has been reflected in new practices for recruiting and training future top civil servants. In Belgium, at some levels of government, these practices include for instance mandatory training prior to the appointment of public managers. This training aims at developing the managerial skills of the Walloon and French-speaking public services leaders. Doing so, the purpose is to guarantee the objectification of public managers’ nomination. But so far, do these trainings develop the skills highlighted by the theoretical models above? Are they in line with the ambitions of public management reforms of the last thirty years? From these first questions, we analyse on the one hand the training system genesis and the interactions between the original actors, and on the other hand, the effects of the training, in a critical perspective. Our study of the training effects is critical for two reasons. First, it questions the role of training in the transmission of the dominant principles conveyed by the NPM and its successors. Second, it considers the role of this training in the reproduction of power games between actors. In other words, we analyse how the compulsory training actually reflects a new conception of public managers and their competencies. Moreover, we consider the impact of this training on the political-administrative system and the power relations included. To this end, we articulate two distinctive approaches: one inspired by the strategic analysis (Crozier & Friedberg, 1977) to understand the interactions between actors at the genesis of the dispositive; and the other one inspired by Critical Management Education (CME), emphasizing the role of management training in the transmission of dominant ideology (Caproni & Arias, 1997). [less ▲]

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See detailIdentification of the main parameters controlling the plasticity of ceramic pastes: The case study of the Marrakech region (Morocco)
El Idrissi, Hicham; Fontaine, François ULg

Poster (2015, July)

Numerous traditional ceramic workshops occur within a range of 10 to 80 km around the city of Marrakech. Our study aims to identify the main parameters controlling the plasticity of pastes used by the ... [more ▼]

Numerous traditional ceramic workshops occur within a range of 10 to 80 km around the city of Marrakech. Our study aims to identify the main parameters controlling the plasticity of pastes used by the artisans. To reach this goal, we characterize by X-ray diffraction, granulometry and plasticity index (PI) the local raw clayey material. The investigation of 26 whole pastes shows the dominance of quartz (20 to 50%) and clay minerals (25 to 60%) with K-feldspar (2 to 17%), plagioclase (2 to 25%), calcite (0 to 18%), dolomite (0 to 15%), goethite (0 to7%) and trace of hematite and anhydrite (< 3%). Amphibole occurs in trace (< 5%) but only in some samples. The clay minerals are diversified, including illite (10 to 40%), kaolinite (2 to 15%), mixed-layer (ML) (0 to 10%), smectite, vermiculite and chlorite (0 to 5%), and pyrophyllite-talc association (0 to 8%). Sepiolite (12%) is only present in one paste. The grain size is made by variable proportions of sand (5 to 65%), silt (12 to 53%) and clayey fraction (18 to 66%). The Plasticity index (PI) indicates the presence of two principals groups of pastes. (1) The first group is characterized by PI values ranging between 15 to 18. Their moderate plasticity behavior is related either to the low rate of clayey fraction and/or to the absence of plastic clays like smectites and mixed layer with smectitic sheets. (2) The PI of second group ranges between 20 to 32. The high plasticity values are influenced by the presence of specific clayey minerals like talc-pyrophyllite or sepiolite, or by the high content of smectite plus smectitic mixed-layers within the clayey (< 2 micron) fraction. Only one sample without any of these plastic minerals but with a high content of clayey fraction is characterized by a high PI value (24). We concluded that the workability of ceramic paste in Marrakech region is controlled by a combination of factors, dominated by the grain size distribution and the content in plastic clay minerals within the fine fraction. [less ▲]

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See detailModifications acoustiques de la voix d’enseignantes au cours de la journée et de l’année scolaire
Remacle, Angélique ULg; David, Claire; Petillon, Caroline et al

Conference (2015, June 30)

Introduction Les enseignants font partie des professionnels de la voix, définis comme des travailleurs qui ne peuvent se passer de leur voix dans l’exercice de leur profession, et qui à ce titre ... [more ▼]

Introduction Les enseignants font partie des professionnels de la voix, définis comme des travailleurs qui ne peuvent se passer de leur voix dans l’exercice de leur profession, et qui à ce titre nécessitent une qualité de vocale constante (1). Cette population est particulièrement à risque et constitue le groupe de travailleurs le plus nombreux à consulter les ORL pour cause de dysphonie (2). Dans ce contexte, la recherche tente d’identifier les indices acoustiques de la fatigue vocale dans le but d’améliorer le dépistage précoce des problèmes de voix, leur traitement et leur prévention. Cette étude menée in situ a pour objectif de mettre en évidence des modifications acoustiques et prosodiques consécutives à 1) une journée de travail et 2) cinq mois de travail en milieu scolaire. Méthode La population est constituée de 22 enseignantes du primaire ayant moins de 5 années d’expérience. Pour chaque participante, cinq /a/ tenus ainsi que la lecture d’un texte ont été enregistrés 1) à deux moments de la journée de travail, soit au matin et au soir, et 2) à trois temps de l’année, soit en octobre (T0), en décembre (T1) et en février (T2). Sur les voyelles tenues, nous avons mesuré le temps maximum phonatoire (TMP), la fréquence moyenne, le jitter, le shimmer, et le rapport harmoniques/bruit (HNR). Sur les textes, nous avons mesuré la fréquence moyenne, la variation de fréquence et d’intensité (écart-type), ainsi que des paramètres relatifs au débit de parole (nombre de syllabes par seconde, nombre de pauses et durée moyenne des pauses). Pour chaque paramètre, une ANOVA en mesure répétées (2 moments * 3 temps) a été réalisée. Résultats L’effet principal du moment montre une augmentation de la fréquence moyenne mesurée sur les voyelles et sur le texte suite à une journée de travail (p<.01). Parallèlement, le TMP et le HNR augmentent (p<.01), tandis que le jitter et le shimmer diminuent en fin de journée (p<.05). Les mesures de débit montrent que les enseignantes tendent à faire moins de pauses lors de la lecture de texte en fin de journée, et que ces pauses sont de plus courte durée (p<.05). L’effet principal du temps montre une augmentation de la fréquence moyenne des voyelles et du texte au cours de l’année (p<.01), avec des valeurs plus élevées observées en décembre (T1). Les mesures relatives au débit montrent également une augmentation du nombre de syllabes par seconde (p<.01) et une tendance des locutrices à faire moins de pauses. Conclusion L’évolution des paramètres observés suggère une augmentation de la fatigue vocale et un comportement phonatoire davantage hyperfonctionnel au cours de la journée et au cours de l’année. Les résultats montrent une dégradation vocale majorée au mois de décembre, en comparaison avec les autres moments de l’année. Bibliographie 1.Titze IR, Lemke J, Montequin D. Populations in the U.S. workforce who rely on voice as a primary tool of trade: A preliminary report. Journal of Voice. 1997;11(3):254-259. 2. Remacle, A., Petitfils, C., Lejeune, L., Finck, C., & Morsomme, D. Quel est le profil professionnel des patients consultant en phoniatrie ? 70e Congrès de la Société Française de Phoniatrie, Paris, France. (13 octobre 2014). [less ▲]

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