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See detailA connection between the instability strips of ZZ Ceti and V777 Her white dwarfs
Van Grootel, Valérie ULg; Fontaine, Gilles; Brassard, Pierre et al

in Astronomy and Astrophysics (2015), 575

Aims. We aim to determine the theoretical instability strips of white dwarfs with diverse H and He content in their atmospheres, from a solar composition to a H-depleted atmosphere. Pulsators with mixed H ... [more ▼]

Aims. We aim to determine the theoretical instability strips of white dwarfs with diverse H and He content in their atmospheres, from a solar composition to a H-depleted atmosphere. Pulsators with mixed H-He atmospheres are indeed known to exist, and these are the white dwarfs in cataclysmic accreting systems of the GW Lib type. We thus also aim to determine the range of periods of excited pulsation modes, and to qualitatively compare these to the observed periods in GW Lib white dwarf pulsators. Methods. In the first full nonadiabatic stability analysis of pulsators of this kind, we applied a time-dependent convection treatment and an energy leakage argument to compute, for cooling models of white dwarfs with various masses and envelope compositions, the location of the blue and the red edges, as well as the properties of pulsation modes. Results. We find that our derived instability strips form a true continuum in the log g-Teff plane and that their individual location depends uniquely on the assumed atmospheric composition, from the solar composition models at low effective temperatures to the H-depleted models at much higher temperatures. Taking into account our previous results from the ZZ Ceti (pure H atmosphere) and V777 Her (pure He atmosphere) white dwarf pulsators, this implies that all of these instability domains are connected via the same fundamental driving mechanism. Applying our results to the case of white dwarf pulsators of the GW Lib type, we find that our theoretical instability strips can qualitatively account for all of the known cases. The computed range of periods of excited modes also compares qualitatively very well to the observed ones. Conclusions. The GW Lib pulsators are very similar in nature to ZZ Ceti and V777 Her white dwarfs. It is the diverse chemical compositions in their atmosphere and envelope that defines their specific pulsation properties. Beyond GW Lib pulsators, white dwarfs can sometimes exhibit mixed H-He atmospheres, such as in the recently found proto-He white dwarf pulsators. Our results open the way towards quantitative asteroseismology of these various kinds of white dwarfs. [less ▲]

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See detailComplexity markers in morphosyntactic productions in French-speaking children with specific language impairment (SLI)
Prigent, Gaïd ULg; Parisse, Christophe; Leclercq, Anne-Lise ULg et al

in Clinical Linguistics & Phonetics (2015)

The usage-based theory considers that the morphosyntactic productions of children with SLI are particularly dependent on input frequency. When producing complex syntax, the language of these children is ... [more ▼]

The usage-based theory considers that the morphosyntactic productions of children with SLI are particularly dependent on input frequency. When producing complex syntax, the language of these children is, therefore, predicted to have a lower variability and to contain fewer infrequent morphosyntactic markers than that of younger children matched on morphosyntactic abilities. Using a spontaneous language task, the current study compared the complexity of the morphological and structural productions of 20 children with SLI and 20 language-matched peers (matched on both morphosyntactic comprehension and mean length of utterance). As expected, results showed that although basic structures were produced in the same way in both groups, several complex forms (i.e. tenses such as Imperfect, Future or Conditional and Conjunctions) were less frequent in the productions of children with SLI. Finally, we attempted to highlight complex linguistic forms that could be good clinical markers for these children. [less ▲]

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See detailFamily farming in a changing landscape : how activities change when forest disappears
Feintrenie, Laurène; Gillet, Pauline ULg; Garcia, Claude et al

Conference (2015, March)

In the Congo Basin forests, local communities used to live from hunting, fishing and gathering, and from slash and burn agriculture. Nowadays, few places remain isolated from the external world, and local ... [more ▼]

In the Congo Basin forests, local communities used to live from hunting, fishing and gathering, and from slash and burn agriculture. Nowadays, few places remain isolated from the external world, and local practices often have to integrate new parameters. How do family farming and forest activities evolve in a changing landscape, when forest disappears? To answer this question we selected three social and ecological systems positioned in specific places on the forest transition curve (Mather 1992), to constitute a synchronic sample of forested social and ecological system representative of the evolution of Congo Basin Forests. We conducted in 2013 and 2014 a deep analysis of family farming in 8 villages distributed in these 3 studied sites. The method crosses a systemic approach with a systematic approach: agrarian diagnoses were conducted in the three sites (Boulaud 2014; Ferlay 2014) to evaluate technical and economic performances of family farming and forest extractive activities, in parallel, census of households were conducted (Codina Llavinia 2014; Gillet et al. 2014; Lehnebach 2014) to range family activities according to their share in the family income and as subsistence means. Results were harmonized and allowed a deep understanding of the strategy of adaptation to changes of households. [less ▲]

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See detailLes pierres aux reins
Castiglione, Vincent ULg; GADISSEUR, Romy ULg; CAVALIER, Etienne ULg

Article for general public (2015)

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See detailAIP mutations : who should we screen ?
Beckers, Albert ULg

in Abstract book - 14th International Pituitary Congress (2015, March)

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See detailX-Linked acro-gigantism (X-LAG) syndrome : a new form of infant-onset pituitary gigantism
Stratakis, CA; Trivellin, G; Rostomyan, Liliya ULg et al

in Abstract book - 14th International Pituitary Congress (2015, March)

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See detailCongenital gigantism in a girl with anterior pituitary hyperplasia : a new genes for a new disease
Lysy, PA; Daly, Adrian ULg; Brunelle, C et al

in Abstract book - 43ème Congrès Annuel de la Société Belge de Pédiatrie (2015, March)

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See detailFires of Pianura: The Antidump Struggle in the Western Outskirt of Naples
De Biase, Marco ULg

in Capitalism, Nature, Socialism (2015), 26(1), 39-58

This ethnographic study aimed at analyzing the rebellion in Pianura, which took place between December 2007 and January 2009 when Naples' streets were covered with rubbish. It was a violent protest ... [more ▼]

This ethnographic study aimed at analyzing the rebellion in Pianura, which took place between December 2007 and January 2009 when Naples' streets were covered with rubbish. It was a violent protest involving some 40.000 people who wanted to object to the reopening of the old dump of Pianura, one of the most toxic in Europe and no longer in use. The fear for their own life, the desperation of local population, and the anger after being attacked by the police during pacific protest gave origin to a real urban guerrilla targeting the political system. This article aims to go beyond the dominant narration of the events developed by the media and the authorities, which interpreted the uprising of Pianura in terms of Nimby (Not in my back yard), and as a mere manifestation of violence that was carried out by a group of extremists. On the contrary, it will be argued that the anti-dump struggle of Pianura, in its diverse forms, was animated by a radical critique of a specific model of local and national development (Gramsci 2007; Della Porta 2006). In order to support this argument the context of Pianura and the various mobilizations set up by the local population are analysed in this article. In addition, the heterogeneous and fragmented nature of the movement is explained through Bayat’s (1997; 2000) concept of “street politics” and that of “rebel bricolage” inspired by the work of Levi-Strauss (1966). More in detail, the analysis is focused on the effects of the “waste politics” on the body of the protesters, which became an important tool of resistance and an instrument to claim fundamental rights (Fassin, Memmi 2004). Finally, this article investigates the role of some groups of ultrà (football supporters) who actively participated in the demonstrations, and their relationship with the criminalizing discourses that were constructed to discredit the struggle. [less ▲]

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See detailEfficient finite element assembly of high order Whitney forms
Marsic, Nicolas ULg; Geuzaine, Christophe ULg

in IET Science, Measurement & Technology (2015), 9(2), 204-210

This study presents an efficient method for the finite element assembly of high order Whitney elements. The authors start by reviewing the classical assembly technique and by highlighting the most time ... [more ▼]

This study presents an efficient method for the finite element assembly of high order Whitney elements. The authors start by reviewing the classical assembly technique and by highlighting the most time consuming part. Then, they show how this classical approach can be reformulated into a computationally efficient matrix-matrix product. They also address the global orientation problem of the vector valued basis functions. They conclude by presenting numerical results for a three-dimensional wave propagation problem. [less ▲]

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See detailA generalized moving-boundary algorithm to predict the heat transfer rate of counterflow heat exchangers for any phase configuration
Bell, Ian; Quoilin, Sylvain ULg; Georges, Emeline ULg et al

in Applied Thermal Engineering (2015), 79

In this work, a novel and robust solution approach is presented that can be used to predict the steady-state thermal heat transfer rate for counterflow heat exchangers with any combination of single-phase ... [more ▼]

In this work, a novel and robust solution approach is presented that can be used to predict the steady-state thermal heat transfer rate for counterflow heat exchangers with any combination of single-phase and two-phase conditions within the heat exchanger. This methodology allows for multiple internal pinching points, as well as all permutations of subcooled liquid, two-phase and superheated vapor sections for the hot and cold fluids. A residual function based on the matching of the required and available thermal conductances in each section is derived, and Brent's method is then used to drive the residual to zero. Examples are presented for the application of this methodology to a water-heated n-Propane evaporator. The computational time required to execute the model for a simple case is on the order of one millisecond when the tabular interpolation methods of CoolProp are applied. Source code for the algorithm is provided in the Python programming language as an appendix. [less ▲]

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See detailFilles et garçons : ensemble, c'est tout ?
Lafontaine, Dominique ULg

in Entrées Libres (2015), (97), 2-3

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See detailRumination time, milk yield, milking frequency of grazing dairy cows milked by a mobile automatic system during mild heat stress
Lessire, Françoise ULg; Hornick, Jean-Luc ULg; Minet, Julien ULg et al

in Advances in Animal Biosciences (2015), 6(01), 12-14

Grazing dairy cows milked by an automatic system (AS) experienced mild heat stress (HS) periods, twice during the summer. The daily temperature humidity index (THI) during these periods were higher than ... [more ▼]

Grazing dairy cows milked by an automatic system (AS) experienced mild heat stress (HS) periods, twice during the summer. The daily temperature humidity index (THI) during these periods were higher than 72. Milk production, as well as milking frequency, rumination time and milk fat to protein ratio (F/P) during these periods were compared to adjacent periods with mean THI of 61. The daily milking frequency, the total number of visits to AS and the milk production were significantly higher in HS periods (2.12 vs 1.97, 2.99 vs 2.69, and 19.7 vs 18.5 kg milk per cow, respectively). There were significant interactions between times and periods for milking frequency and number of visits, while the daily rumination time was significantly lower (339 vs 419 min) and the F/P in milk tended to be decreased (1.17 vs 1.23). These results could be explained by changes in cow behaviour during HS periods. [less ▲]

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See detailL'optimisation topologique et la fabrication additive, amélioration de la chaine de conception
Louvigny, Yannick ULg; Nzisabira, Jonathan ULg; Meunier, Bertrand et al

in 14ème colloque national AIP PRIMECA : Produits, Procédés, Systèmes intelligents et durables (2015, March)

L'intérêt de combiner l'optimisation topologique avec les méthodes de fabrication additive vient du fait que d'une part, l'optimisation topologique permet de générer des géométries complexes que les ... [more ▼]

L'intérêt de combiner l'optimisation topologique avec les méthodes de fabrication additive vient du fait que d'une part, l'optimisation topologique permet de générer des géométries complexes que les procédés d'usinage conventionnels ne sont pas capables de réaliser et que, d'autre part, la fabrication additive permet de réaliser des formes complexes telles que des cavités emprisonnées dans un volume ou des canaux non rectilignes, impossibles à reproduire en fonderie ou par usinage. De plus et contrairement aux techniques traditionnelles, la réalisation des géométries complexes n'influence pas le coût pour les techniques additives. Pour ces techniques, le coût est lié principalement au volume de la pièce. La complexité de la pièce n'est plus un problème mais un atout. Toutefois cette combinaison n'est pas encore exploitable au niveau industriel. En effet, les résultats fournis par l'optimisation topologique doivent être modifiés, souvent manuellement, pour les rendre utilisables par les méthodes de fabrication additive. Et ces modifications coûtent cher. Il est donc intéressant de limiter ou au mieux d'éliminer les étapes manuelles de la chaîne de conception. Ce papier propose une chaîne de conception optimisée pour une pièce devant être fabriquée par les méthodes additives. En outre, la prise en compte des contraintes inhérentes aux procédés de fabrication par addition de matière reste problématique. Une démarche simplifiée est proposée pour identifier les types de contraintes inhérentes aux procédés de fabrication par addition de matière, les quantifier pour certaines techniques et les intégrer dans le code d'optimisation topologique. La nouvelle chaine de conception minimise les interventions du concepteur qui rendent le processus plus lourd et moins viable industriellement. Dans cette nouvelle chaîne de conception, certaines étapes sont réalisées plus rapidement et génèrent de meilleurs résultats. [less ▲]

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See detailApproche agroforestière. Synthèse des travaux menés par le projet DACEFI2 en agroforesterie. Document de capitalisation.
Boldrini, Sylvie; Meunier, Quentin; Boukouendji, Basile et al

E-print/Working paper (2015)

Le projet DACEFI-2 a eu pour mission première la promotion de la foresterie communautaire comme outil de développement des communautés rurales. L’approche au Gabon en matière de gestion des terroirs ... [more ▼]

Le projet DACEFI-2 a eu pour mission première la promotion de la foresterie communautaire comme outil de développement des communautés rurales. L’approche au Gabon en matière de gestion des terroirs villageois s’est voulue plus embrassante, promouvant en sus de l’exploitation forestière des activités comme l’agriculture, le maraîchage, la collecte des produits forestiers non ligneux ou encore l’agroforesterie. L’agroforesterie est une thématique qui converge parfaitement avec la gestion raisonnée de la forêt, et idéalement avec les modes d’interaction préexistants des villageois avec celle-ci. Concilier dans un même espace la culture de plantes vivrières et l’accès à des arbres à fort intérêt socio-économique apporte une plus-value notoire aux parcelles cultivées. L’optimisation des techniques culturales permet une meilleure productivité et une incitation à la sédentarisation des cultures, élément important à considérer compte tenu des difficultés d’entretien des parcelles éloignées du village (notamment liées aux dégâts causés par les animaux). Ce recueil compile les travaux réalisés en agroforesterie par les équipes du projet DACEFI-2. Il rappelle la stratégie d’intervention et les différentes activités menées, de la sensibilisation auprès des plus jeunes à la promotion de certains produits forestiers non ligneux à potentiel économique avéré. La promotion de l’arbre, de la récolte de la graine jusqu’à sa plantation en passant par sa mise en pépinière aura également animé toute l’équipe durant ces années d’exercice, afin de faire un peu plus valoir ses multiples intérêts et susciter les efforts de gestion, de conservation et de reboisement. [less ▲]

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See detailThe Solar Energetic Particle experiment on MAVEN: first results
Larson, Davin; Lillis; Dunn et al

Conference (2015, March)

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