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See detailBioaccumulation of polybrominated diphenyl ethers (PBDEs) in Gammarus pulex: Relative importance of different exposure routes and multipathway modeling
Lebrun, Jérémie; Leroy, Delphine; Giusti, Arnaud ULg et al

in Aquatic Toxicology (2014), 154

Characterizing the exposure routes of an organism and its ability to regulate accumulated contaminants is a crucial step toward developing a biomonitor. To date, very little data are available on the ... [more ▼]

Characterizing the exposure routes of an organism and its ability to regulate accumulated contaminants is a crucial step toward developing a biomonitor. To date, very little data are available on the bioaccumulation kinetics of PBDEs in freshwater biota. This study aims at investigating the potential use of a litter-degrader widely distributed in European freshwaters, Gammarus pulex, as an indicator of exposure to PBDEs. In aquatic microcosms, gammarids were exposed to a mixture of brominated congeners (BDE-28, 47, 66, 85, 99, 100, 153, 154 and 183) to assess their ability to bioconcentrate PBDEs. Results show that all tested congeners are highly internalized by G. pulex and uptake rates of PBDEs are closely related to their partition coefficients (Kow). The determination of the elimination rate of BDE-47, the congener most readily accumulated by gammarids, indicated that metabolism and excretion of this congener are low in G. pulex, which argues in favor of its use as a quantitative biomonitor. Finally, bioaccumulation experiments were performed using contaminated leaves to determine the relative importance of dietary uptake in the contamination of gammarids. Even though water is the preeminent exposure route, a significant uptake of BDE-47 through food was observed (27%). We propose a biodynamic model that takes into account both exposure routes to describe BDE-47 bioaccumulation. This study supports the use of this ubiquitous amphipod as an early warning monitor of the bioavailable contamination of freshwaters by PBDEs. [less ▲]

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See detailThe Double-Sarcophagus of Hierapytna (Creta). A Reassessment
Veymiers, Richard ULg

Conference (2014, September)

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See detailAutonomie de la volonté et concurrence régulatoire – le cas des relations familiales internationales
Wautelet, Patrick ULg

in Fulchiron, Hugues; Bergé, Jean-Sylvestre (Eds.) Vers un statut européen de la famille ? (2014)

L'autonomie de la volonté a connu un essor considérable dans le règlement des relations familiales internationales. Au-delà de la consécration toujours plus importante de l'autonomie de la volonté comme ... [more ▼]

L'autonomie de la volonté a connu un essor considérable dans le règlement des relations familiales internationales. Au-delà de la consécration toujours plus importante de l'autonomie de la volonté comme fondement de la règle de conflit de lois en matière familiale, la liberté des parties a reçu ces dernières années un appui important par le biais d'une jurisprudence ambitieuse tant de la Cour de justice de l'Union que de la Cour européenne des droits de l'homme. Dans le même temps, force est bien de constater que le droit de la famille semble constituer un îlot de résistance tenace face au mouvement d'unification et d'harmonisation. Les ingrédients semblent dès lors réunis pour le développement d'une véritable concurrence législative qui pourrait mener au spectre de la 'race to the bottom'. A l'offre de droits aux contenus différents se conjuge en effet une certaine possibilité de choix par les parties. Cette liberté de choix constitue un avatar évident de la mobilité qui fonde le pouvoir d'arbitrage des acteurs privés. La présente contribution a pour objectif de s'interroger sur l'existence réelle d'une telle concurrence normative. [less ▲]

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See detailExperimental evidence and numerical prediction of nonlinear modal interactions in a real-life aerospace structure
Renson, Ludovic ULg; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

in Proceedings of the ISMA 2014 conference (2014, September)

During the last decade, the existence of nonlinear behaviour in spacecraft dynamic testing was frequently attested. However, current practice in industry is still to ignore nonlinearities, arguably ... [more ▼]

During the last decade, the existence of nonlinear behaviour in spacecraft dynamic testing was frequently attested. However, current practice in industry is still to ignore nonlinearities, arguably because their analysis is regarded as impractical. The objective of the present contribution is to show that there now exists experimental and numerical methodologies which can deal with nonlinear phenomena in real-life structures. Specifically, this study investigates nonlinear modal interactions evidenced during the qualification campaign of the SmallSat spacecraft developed by EADS-Astrium. The ability to understand and reliably predict such interactions is of utmost importance as they may involve energy transfer between modes and, in turn, jeopardise the structural integrity. The paper proceeds in two steps, leading to great-fidelity reproductions of the experimental observations. In the first step, sine-sweep data collected during the qualification campaign are exploited to build a nonlinear computational model of the SmallSat with good predictive capabilities. To this end, the complete progression through nonlinearity detection, characterisation and parameter estimation is carried out by means of several techniques, such as the wavelet transform and the restoring force surface method. In the second step, the computational model is exploited through continuation algorithms to compute the nonlinear normal modes of the spacecraft and predict potential interactions. A very good agreement between experimental and numerical results is obtained for 2:1 interactions between modes with non-commensurate linear frequencies. [less ▲]

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See detailLes objectifs de la formation des soignants en Education Thérapeutique du Patient : une proposition
Pétré, Benoît ULg; Guillaume, Michèle ULg; LEGRAND, Catherine et al

Conference (2014, September)

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See detailApport de la pédologie au conseil de fumure personnalisé par l’intégration d’arguments morphospatiaux et physico-chimiques impliquant de nouveaux outils d’analyse : la carte numérique des sols de Wallonie et la spectroscopie proche infrarouge
Genot, Valérie ULg

Doctoral thesis (2014)

The current environmental and agronomical context requires that farmers manage their inputs with the utmost precision, which can only be achieved by developing state of the art tools leading to clear ... [more ▼]

The current environmental and agronomical context requires that farmers manage their inputs with the utmost precision, which can only be achieved by developing state of the art tools leading to clear, exhaustive and efficient decisions. In this context, soil analysis being a vital tool, we have endeavoured to refine the advice given to farmers by the Walloon soil analysis laboratories, members of the non-profit-making organization REQUASUD, by studying the opportunity of developing two complementary tools, one cartographic, the other analytical, which can be integrated in the daily running of a laboratory. First of all, to ensure that soil analysis provides reliable results, it is essential for the sample to be as representative as possible of the plot. Lacking this representativity, an analytical result, however accurate, would be devoid of meaning and give the farmer misleading advice. In the field, the main obstacle for the soil sampler is the recognition of soil criteria which are however essential in establishing fertility advice, especially in Wallonia (southern Belgium) due to a high soil variability. The Digital Soil Map of Wallonia, surveyed at a scale of 1/5000, should prove to be an invaluable tool that can be used easily and directly for routine work not only by soil samplers but also by farmers and agronomists. That’s why a mapping web portal REQUACARTO has been designed to help define homogenous morpho-pedological areas and to validate them in different situations. Furthermore, in Wallonia, certain soil properties seldom undergo routine analysis, despite their importance in fertility advice, and when they do, they result in the use of extracts which are harmful to the environment and to health. Therefore we investigated the feasibility of a routine application of near infrared reflectance spectroscopy (NIRS) to determine these soil properties. This technique offers a number of advantages compared to analyses carried out according to reference methods: speed, respect of the environment and health, recovery of the sample, ease of use and thus economy. On a selection of representative samples of the pedological context of Wallonia, for which we also had analytical results of exchange cation capacity, as well as rates of carbon, nitrogen and clay, trials were performed using NIRS instead of or in addition to laboratory reference analyses. The findings highlight the relevance of using NIRS and were substantiated by a study of repeatability and intermediate precision of the technique. The spectral library was then transferred to the different soil analysis laboratories of the network. The goal is multiple: to offer further analyses to farmers at no extra cost, reduce the number of analyses performed according to reference methods and implement the spectral library with samples not predicted by NIRS to improve predictions. [less ▲]

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See detailStand structure and species co-occurence in mixed and monodominant Central African tropical forests
Djuikouo, Marie Noël K.; Peh, Kelvin S.H.; Nguembou et al

in Journal of Tropical Ecology (2014), 30(5), 447-455

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See detailβ 5 tubulin and 15-protofilament microtubules appeared in supporting cells of the Corti’s organ during development in rodents
Renauld, Justine ULg; Thelen, Nicolas ULg; Johnen, Nicolas et al

Conference (2014, August 31)

A feature of the organ of Corti’s supporting cells is the presence of an abundant cytoskeleton which is mainly composed of microtubules. These supporting cells have also been shown to contain a minor ... [more ▼]

A feature of the organ of Corti’s supporting cells is the presence of an abundant cytoskeleton which is mainly composed of microtubules. These supporting cells have also been shown to contain a minor mammalian tubulin, the β5-tubulin [1], recently related as a biomarker for cancer outcome [2] and cell proliferation [3]. It was shown that a β-tubulin isoform can specified the microtubule architecture, such as the expression of the Moth β2 in the Drosophila testes imposed the 16 protofilaments (16pf) structure on the corresponding subset of Drosophila microtubules, which normally contain 13pf [4]. Moreover, supporting cell microtubules are formed by 15pf instead of the canonical 13, a unique fact among vertebrates [5]. Such a protofilament configuration has been observed in C. elegans’ neurons which are responsible for the mechanosensory sense of touch [6]. It was also shown that these 15pf microtubules were essential to the proper functioning of these mechanosensory neurons [6]. To determine the role of this particular tubulin in the auditory organ and its possible involvement in the formation of the unusual 15pf microtubules of supporting cells, we studied the spatiotemporal localization of β5-tubulin during development in rats from embryonic day 18 until P25 (25th postnatal day). We also analyzed the localization of β5-tubulin mRNA expression in the Corti’s organ. Then we examined the fine structure of microtubules at the electron microscope level. For these experiments, we used an early postnatal stage and a late postnatal stage. Our results showed that β5-tubulin, contrary to other β-tubulins, had a unique distribution in the cochlea. This β-tubulin appeared at a postnatal stage, before the opening of the Corti’s tunnel and being restricted to supporting cells, especially in pillar and Deiters cells,. The same localization of β5-tubulin mRNA was observed by in Situ Hybridization. Electron microscopy indicated further that Pillar and Deiters cells were composed by 15-protofilament microtubules at the late postnatal stage (P25). In conclusion, all these data strongly suggest that there is a relationship between the presence of β5-tubulin and 15-protofilament microtubules in the supporting cells of the auditory organ. Further studies are now needed to elucidate their role. [less ▲]

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See detailInteractions in massive binaries: spectral modelling – CoMBiSpeC – and observational analyses
Palate, Matthieu ULg

Doctoral thesis (2014)

Massive stars are very important to the life of the galaxiesbut they are rare and many open questions on their formation, evolution and characteristics remain. One of the best ways to improve our ... [more ▼]

Massive stars are very important to the life of the galaxiesbut they are rare and many open questions on their formation, evolution and characteristics remain. One of the best ways to improve our knowledge on massive stars is to study massive binaries (that represent at least 50% of massive stars see Mahy et al. 2009, and Sana & Evans 2011) and their spectra. Spectral and atmosphere modelling of stars are very interesting tools that are now often used in spectral analyses. However, these models are designed for single spherical stars. In this context, we have developed a numerical code of spectral modelling of massive binary systems: CoMBiSpeC (code of massive binary spectral computation) that computes the spectra of massive binary systems and accounts for various effects that affect these systems. Our models, and the observational analyses of the four binary systems presented in the second part of this work, have allowed to explain several effects linked to binarity: luminosity class discrepancy, temperature distribution, Struve-Sahade effect, and some kind of line profile variations. In summary, CoMBiSpeC is a first step in the spectral modelling of massive binary systems and several improvements are still needed to be able to study all massive binaries. Nevertheless, this model can explain and reproduce various observed phenomena which was the main goal of this thesis. [less ▲]

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See detail“Latin American women in the global city of Brussels, defying their disadvantageous gendered positions through the construction of Transnational Artistic Careers.”
Vivas Romero, Maria ULg

Scientific conference (2014, August 26)

The life goal of constructing Transnational Artistic Careers might open up transnational opportunities for some migrant women who wish to participate in today’s global cities cultural domains. This paper ... [more ▼]

The life goal of constructing Transnational Artistic Careers might open up transnational opportunities for some migrant women who wish to participate in today’s global cities cultural domains. This paper is based on my first observations in the field as a PhD student through, which I encountered complex dynamics of Latin American and Gender identities constructions, both among my participants and myself. Therefore, drawing from a transnational and cosmopolitan practices perspectives, through this paper I refer to Transnational Artistic Careers that served the women invoked in my analysis, to develop cosmopolitan skills and competencies by which they develop multiple forms of identification. These competencies I will argue served these women as a tool to find recognition as well as to express, a sense of belonging that extended beyond ethnic categorizations deployed by more hegemonic perspectives. These women described themselves as the entrepreneurs of their own careers, which later helped them to engage in Cosmopolitan Sociabilities that ultimately served them to develop alternative representations of how they ultimately wanted to be known by “others”. By aiming to discover different forms of Transnational Artistic Careers and Cosmopolitan Sociabilities this paper, focuses on the agency by which these women contested, resisted and empowered themselves against racialized, and ethnicized global hierarchies of power. [less ▲]

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See detailIncreasing the efficiency of Organic Rankine Cycle Technology by means of Multivariable Predictive Control
Hernandez Naranjo, Jairo Andrés ULg; Desideri, Adriano ULg; Ionescu, Clara et al

Conference (2014, August 25)

The Organic Rankine Cycle (ORC) technology has become very popular, as it is extremely suitable for waste heat recovery from low-grade heat sources. As the ORC system is a strongly coupled nonlinear ... [more ▼]

The Organic Rankine Cycle (ORC) technology has become very popular, as it is extremely suitable for waste heat recovery from low-grade heat sources. As the ORC system is a strongly coupled nonlinear multiple-input multiple-output (MIMO) process, conventional control strategies (e.g. PID) may not achieve satisfactory results. In this contribution our focus is on the accurate regulation of the superheating, in order to increase the e fficiency of the cycle and to avoid the formation of liquid droplets that could damage the expander. To this end, a multivariable Model Predictive Control (MPC) strategy is proposed, its performance is compared to the one of PI controllers for the case of variable waste-heat source profi les. [less ▲]

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See detailmodelling heat and mass transfer during convective drying of a building material
Kahlerras, Loubna ULg

Conference (2014, August 24)

The purpose of this study is to characterize experimentally the behaviour of a cement mortar during its convective drying. The work presented here focuses on mortars with water-to cement ratios (w/C) of 0 ... [more ▼]

The purpose of this study is to characterize experimentally the behaviour of a cement mortar during its convective drying. The work presented here focuses on mortars with water-to cement ratios (w/C) of 0, 5. The drying tests are realized in a convective dryer designed for the drying of small samples (0 - 8g). Experiences are realized with different conditions of drying air temperature (60, 90 and 130 °C) and velocity (2, 3 and 5 m/s) the results show the influence of temperature and velocity on drying curve. Mathematical models have been used for the description of drying curves. The exponential mathematical model seems the most adequate to describe the drying curves of cement mortars, with correlation coefficients changing with the air temperature and velocity and close to unity. The convective mass and heat transfer coefficients are determined from the experimental data. The results showed that both mass and heat transfer coefficients were affected by the air temperature and velocity. The convective mass transfer coefficient changed from 0.0232m/s at V=2m/s to 0.045m/s at V=5m/s, and from 0.055 m/s at 60°c to 0.023 at 130°c. Heat transfer coefficient changed from 14.767 w/m2°c at V=2m/s to 28.64 w/m2°c at V=5m/s and from 7.71 at 60° c to 14.77 at 130°c The temperature dependency of the two coefficients was expressed using an Arrhenius-type equation and related parameters were deduced [less ▲]

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See detailExperimental study of the drying kinetic of mortar
Kahlerras, Loubna ULg

Conference (2014, August 24)

This work reports the results of an experimental study concerning on one hand the influence of water-to cement ratios (W/C), and the role of aggregates on the other hand on the drying kinetics of cement ... [more ▼]

This work reports the results of an experimental study concerning on one hand the influence of water-to cement ratios (W/C), and the role of aggregates on the other hand on the drying kinetics of cement pastes during thermal drying. Three types of cement pastes were realized and studied; cement pastes with ratios W/C 0.4, W/C 0.5 and mortar with ratio W/C 0.5. These tries present the advantage to reproduce the natural conditions met in the problems of interaction atmosphere and material. Cylindrical samples of cement of size (17 X 13) mm are dried in a convective dryer. The sample is continuously weighed during the drying test and its mass is recorded every 60 s, in the purpose to obtain the drying curves. The results show that the increase of the W/C ratio leads to an increase of the drying rate due to the increase of the initial porosity. The effect of the introduction of aggregates is observable by the comparison of the drying curve obtained for the mortar and the cement pastes. The results show a decrease of the drying kinetics with mortars. The results also show that the air drying temperature has a large impact on the drying process, increasing the temperature leading to significant drying time reduction. The Effective diffusion coefficient is calculated by comparison between the experimental results and the analytical solution of Fick’s equation written for a finite medium. [less ▲]

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See detailThe taste bud and the form. Ethnography of sensory labs
Vangeebergen, Thomas ULg

Conference (2014, August 22)

Sensory analyses present an opportunity to challenge classical dualism, especially when it is about taste. During long-term fieldworks, I accompanied several types of sensory expert panels, which had the ... [more ▼]

Sensory analyses present an opportunity to challenge classical dualism, especially when it is about taste. During long-term fieldworks, I accompanied several types of sensory expert panels, which had the mission to discriminate different sorts of products and define their respective sensory profile. I was interested to observe the period of training to understand how those people had acquired their expertise, and how their attention toward their own sensations were entangled to scientific infrastructures. Using sensory ethnographic methods, I assisted to the emergence of a particular world, in which the classical categories for science practices and taste perception were completely blurred. To establish a common truth, through sturdy and stable categories, appears to be compatible with personal moods and dispositions, singular and hedonic judgments, sociocultural grounded sensorium, contingent elements, and indeterminate parameters. Resorting to standard tests, educated and coached judges, statistical treatments, specific vocabulary, comparisons to physic-chemical analysis and various other apparatuses, these labs tempt to define and assess some food products. The goal of those examinations could be multiple: to outline consumers¿ feelings and choices, to check the quality of production, to search new applications, or to improve a current array. What interested me is the quest to an object practically exploitable in an industrial and commercial context, avoiding all kind of idiosyncratic experiences. In this presentation, I would tempt an analysis of those particular tests, focusing on the double bind of testing products and testing consumers, and searching to assess the causes of organoleptic variability. [less ▲]

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See detailMetropolitan governance rescaling in Belgium, France and United Kingdom. Studying boundaries of urban governments through the application of an analytical framework for institutional changes.
Breuer, Christophe ULg

Conference (2014, August 20)

Second tier European cities (small metropolis or regional cities) are subject to permanent reconfigurations of their governance. These changes are the response to both external and internal ... [more ▼]

Second tier European cities (small metropolis or regional cities) are subject to permanent reconfigurations of their governance. These changes are the response to both external and internal transformations. On the one side, they are facing external pressures as increased competition between cities, European integration, legislative evolution or paradigm switch. On the other side, cities are dealing with internal problems: urban sprawl, socio-spatial segregation, actors’ fragmentation, financial issues, etc. These tensions renew themselves and take various shapes. They are wondering cities governance and ways to manage them. To cope with new challenges in a new context, cities are trying to reconfigure their collective action in a new spatiality and with new coordination modes. In this context, inherited institutional boundaries – that could be seen as obsolete or inadequate in a changing World – are particularly under pressure. Cities governments and their spatial limits are a central issue for researchers, politicians and urban actors, and a major component of the urban or metropolitan governance. Although second-tier cities are an essential part of the “polycentric system of European cities”, attention has essentially been focused on large metropolis and capital cities, where the problem occurred earlier. Furthermore, there is an extended literature on institutional change and the “rescaling”, but research mainly focused on the response of cities to economic changes; few analysis offer a good comprehension of particular trajectories and evolution of cities limits which are highly embedded in local context. These shortcomings make the reading of contemporary mutations particularly complex for local actors. Our paper presents our research on the development and the validation of an analytical framework to interpret changes in cities’ governments boundaries. We improved and used a framework based on institutional change and social change, which combined both institutional design theories and self-organization theories. The analytical framework had been tested on the last decades government limits changes of regional cities and small metropolis in France (Saint-Étienne, Metz), United Kingdom (Sheffield) and Belgium (Liège, Brussels). The research was carried on with historical and geographical data collected during research stays in each of these cities: historical evolution of cities limits, legislation’ development, urbanization trajectory, etc. The research leads to some conclusions. Firstly, it is possible to develop a generic analytical framework to identify and interpret mutations of city government limits. This framework helps to make a systematic identification of actors’ dynamics, internal or external pressure and spatial changes, and go ahead apparent dichotomy between quick adjustment and high stability of some governance configuration. Secondly, the analytical model shows there is a common scheme of city limits evolution, which is driven among others things by European common dynamics (specifically economic and political dynamic). Thirdly, despite similarities in cities government boundaries changes, the analytical model demonstrates the importance of local contexts to understand individual evolutions and the specific trajectory of a city’ limits. [less ▲]

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See detailRetrouvailles à vélo avec Dick Annegarn
Demoulin, Laurent ULg

E-print/Working paper (2014)

Le nouveau CD de Dick Annegarn, Vélo va (2014), offre à son auditeur, à travers un bel échantillon de dix chansons, un aperçu des différentes facettes de l’art de l’auteur-compositeur-interprète.

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