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See detailModel polyQ proteins based on the beta-lactamase BlaP: How non-polyQ regions influence the polyQ length-dependent aggregation process
Huynen, Céline ULg

Doctoral thesis (2015)

Neurodegenerative amyloid diseases are fatal disorders representing an important human health and economic burden. Amongst them, nine disorders are classified as polyglutamine (polyQ) diseases, for which ... [more ▼]

Neurodegenerative amyloid diseases are fatal disorders representing an important human health and economic burden. Amongst them, nine disorders are classified as polyglutamine (polyQ) diseases, for which no treatment is yet available. They are all characterized by the pathological expansion of a poly(CAG) sequence, above a specific threshold, within the coding sequence of nine unrelated genes, translated in nine polyQ proteins. The polyQ expansion, the only common point, is the critical determinant for polyQ disease development by triggering protein aggregation into amyloid fibrils. More recent studies however indicate that the protein context modulates the polyQ-induced aggregation process and the disease phenotype. The objectives of my thesis are to deeper investigate the molecular determinants of the complex interplay between the propensity of the polyQ tract to trigger protein aggregation and the modulating role of non-polyQ regions in order to allow the identification of strategies to interfere with the pathological aggregation process. For that purpose, model polyQ proteins, referred to as BlaP-polyQ chimeras, based on the β-lactamase BlaP and polyQ sequences (23 – 79Q) inserted at two positions (197, in between or not unstructured peptides, or 216), are used and their aggregation properties are characterized under several conditions. We first observe that the polyQ length is determinant for BlaP-polyQ chimera aggregation. Indeed, there is a Q-threshold for the aggregation into amyloid fibrils and for fibril elongation. Above this threshold, the aggregation in solution and the elongation rate increase with the length of the polyQ tract, with an exponential rise-to-maximum and a linear regression, respectively, independently of the conformation of the BlaP moiety, and of the position of the polyQ tract within BlaP. Longer polyQ tracts are likely to have a larger conformational flexibility allowing them to more easily adopt an amyloid-aggregation prone conformation. However, the Q-threshold for fibril elongation is much lower than for fibril formation in solution: the polyQ tract requires a larger conformational flexibility to nucleate the formation of fibrils than to elongate them. Secondly, the Q-threshold for fibril formation is lower once the BlaP moiety is unfolded, and BlaP-polyQ chimeras aggregate faster into amyloid fibrils under conditions favoring the unfolding of the BlaP moiety. The native structure of BlaP is likely to impose conformational constraints to moderate and long polyQ tracts that block and decrease, respectively, their propensity to form fibrils. The effects of constraints decrease with the polyQ length. Thirdly, BlaP chimeras with the polyQ tract in position 216 have an increased propensity to trigger the nucleation and the elongation of amyloid fibrils compared to chimeras with the polyQ in position 197. Advanced studies confirm that the propensity of the polyQ tract to aggregate into amyloid fibrils is linked to the conformational flexibility of the polyQ tract, which depends on (i) the polyQ length, (ii) the location of the polyQ tract within BlaP, i.e., a terminal location or embedded within a protein domain, and (iii) the structural properties of the polyQ flanking regions. Finally, we observe that the whole region flanking the polyQ tract in position 197 at its N-terminus has an anti-aggregating property that fully counterbalances the pro-aggregating property of that flanking at the C-terminus. The former imposes strong conformational constraints to the polyQ tract that reduce its conformational flexibility and hence its aggregation propensity. Moreover, these regions are likely to differently affect the solubility of the polyQ protein and hence the driving force for insoluble aggregation. Altogether, our data also suggest that BlaP chimeras aggregate via the commonly described nucleation-dependent polymerization mechanism during which the aggregation is first triggered by polyQ-polyQ interactions, and then a subsequent slight reorganization of the BlaP moiety is required for conversion of aggregates into amyloid fibrils. Based on these results, we should allow the development of therapeutic strategies, targeting specifically the molecular features of the complex interplay between the polyQ and non-polyQ regions during the nucleation and/or elongation of the pathological aggregation of polyQ proteins. [less ▲]

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See detailPourquoi se mobiliser pour la planète rouge?
Stiepen, Arnaud ULg

Conference given outside the academic context (2015)

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See detailWood, the material of tomorrow's retrofits
Ruellan, Guirec ULg; Attia, Shady ULg

in High-quality retrofit and redensification with timber construction systems (2015, June 18)

The construction sector has focused for many years on performance improvement of new constructions. Today's largest problem is the energetic retrofitting of existing buildings. The building retrofit is an ... [more ▼]

The construction sector has focused for many years on performance improvement of new constructions. Today's largest problem is the energetic retrofitting of existing buildings. The building retrofit is an important strategy for energy savings. Building retrofit is addressed towards the real estate in Europe and allows for substantial gains, especially for heating houses and urban densification. However retrofit requires the use of special construction techniques. The problem is quite different from that of the new buildings: adaptation to existing building, heritage conservation, elimination of thermal bridges, etc. In this context, wood is experiencing strong growth in its use in new constructions, due to its qualities. And we think that some of those allow more appropriate responses to retrofit than other traditional materials. In this study, we will first present succinctly the problems related to the renovation, then we will dedicate ourselves to define the characteristics of the wood. The focus will be on some problems that commonly arise in wood constructions. We will then discuss a case, highlighting different characteristics of wood that are particularly important in this particular renovation. This allows us to observe on the ground the coherence of the choice of wood in the renovation. A discussion will close the study by summarizing the advantages and limitations of the use of wood in the renovation This is not to show that wood is one of the most environmentally friendly building materials, or demonstrate the sustainable character of retrofit. This is to see that the timber construction systems can provide an adequate response to many retrofit issues. [less ▲]

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See detailLa limitation du cumul de mandats par les députés wallons
Grandjean, Geoffrey ULg

in Courrier Hebdomadaire du CRISP (2015), 2255-2256

En moyenne, les représentants politiques belges cumulent entre cinq et huit mandats (dont la moitié sont rémunérés). Cette pratique contribue au développement des sentiments de méfiance que nourrit une ... [more ▼]

En moyenne, les représentants politiques belges cumulent entre cinq et huit mandats (dont la moitié sont rémunérés). Cette pratique contribue au développement des sentiments de méfiance que nourrit une partie de la population à l’égard des élus et des institutions. Dans un souci de bonne gouvernance, de nombreux citoyens et acteurs politiques appellent dès lors à une limitation des possibilités légales de cumul de mandats. La traduction récente la plus emblématique de cette préoccupation éthique est le décret décumul adopté en Région wallonne en 2010. Désormais, un député wallon n’a plus le droit de cumuler son mandat avec une fonction de bourgmestre, d’échevin ou de président d’un conseil de l’action sociale. Un quart des membres de chaque groupe politique représenté au Parlement wallon est cependant autorisé à cumuler. Les députés qui bénéficient de cette exception sont désignés sur la base de leur taux de pénétration électorale. Ce mécanisme est le fruit d’un accord politique conclu entre les partenaires du gouvernement régional (PS, Écolo, CDH). Son adoption a fait l’objet de débats nombreux et souvent tendus entre les partis politiques, en ce compris au sein de la majorité. Ce Courrier hebdomadaire retrace l’ensemble du processus législatif à la base du décret décumul. Il replace l’initiative dans son contexte et analyse le jeu des différents acteurs, en réservant une attention particulière aux divers arguments politiques, techniques et surtout juridiques qui ont été mobilisés. G. Grandjean se penche également sur les effets que le décret a eus pour les députés élus lors du scrutin régional wallon du 25 mai 2014. Enfin, il s’interroge sur l’avenir du décret décumul, que certains voudraient réformer, voire supprimer. [less ▲]

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See detailLe saut d'index, on vire à droite ?
Grandjean, Geoffrey ULg

Conference given outside the academic context (2015)

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See detailScreening and analyzing retrofit systems for zero energy renovation and their potential application in Liège, Belgium
Attia, Shady ULg

in AEE INTEC (Ed.) High-quality retrofit and redensification with timber construction systems (2015, June 18)

Retrofit systems for Zero Energy Renovation comes energy as the most topical subject in the Belgian construction sector. Concepts and solutions for zero energy renovation are a new topic. Since 2006 ... [more ▼]

Retrofit systems for Zero Energy Renovation comes energy as the most topical subject in the Belgian construction sector. Concepts and solutions for zero energy renovation are a new topic. Since 2006, Belgium has been striving to achieve the European ambitions of fulfilling the Kyoto Protocol by insulating more effectively and reducing CO2 emissions associated with the use of fossil fuel for operational and embodied energy in buildings. In 2011, a Belgian decree mandated the construction of nearly zero and nets zero energy buildings by 2020. Following the German PassivHaus Standard performance requirements the Belgian residential sector is aiming to achieve an energy consumption to less than 15 kWh/m2/year and an onsite renewable energy production up to 60% for every newly construct household. In this, context the study will build on grounded knowledge developed and implemented by the IEA ECBCS Annex 50: Prefabricated Systems for Low Energy Renovation of Residential Buildings. The goal of this research is to screen and select a series of envelope retrofitting solutions. The focused aim is to demonstrate validated envelope prototypes and products of different zero energy, timber frame construction systems and composite components. This will include the comparison of timber retrofit systems with conventional systems. Thus inform and support the decision making of policy makers, municipalities, developers, and architects and building engineers in Belgium. [less ▲]

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See detailUncertainty of climate change impact on groundwater reserves – Application to a chalk aquifer
Goderniaux, Pascal; Brouyère, Serge ULg; Wildemeersch, Samuel et al

in Journal of Hydrology (2015), 528

Recent studies have evaluated the impact of climate change on groundwater resources for different geographical and climatic contexts. However, most studies have either not estimated the uncertainty around ... [more ▼]

Recent studies have evaluated the impact of climate change on groundwater resources for different geographical and climatic contexts. However, most studies have either not estimated the uncertainty around projected impacts or have limited the analysis to the uncertainty related to climate models. In this study, the uncertainties around impact projections from several sources (climate models, natural variability of the weather, hydrological model calibration) are calculated and compared for the Geer catchment (465 km2) in Belgium. We use a surface–subsurface integrated model implemented using the finite element code HydroGeoSphere, coupled with climate change scenarios (2010–2085) and the UCODE_2005 inverse model, to assess the uncertainty related to the calibration of the hydrological model. This integrated model provides a more realistic representation of the water exchanges between surface and subsurface domains and constrains more the calibration with the use of both surface and subsurface observed data. Sensitivity and uncertainty analyses were performed on predictions. The linear uncertainty analysis is approximate for this nonlinear system, but it provides some measure of uncertainty for computationally demanding models. Results show that, for the Geer catchment, the most important uncertainty is related to calibration of the hydrological model. The total uncertainty associated with the prediction of groundwater levels remains large. By the end of the century, however, the uncertainty becomes smaller than the predicted decline in groundwater levels. [less ▲]

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See detailRhizobacterial volatiles influence root system architecture, biomass production and allocation of the model grass Brachypodium distachyon (L.) P. Beauv.
Delaplace, Pierre ULg; Ormeño-Lafuente, Elena; Delory, Benjamin ULg et al

Conference (2015, June 18)

Plant growth-promoting rhizobacteria are increasingly considered as a complement of conventional inputs in agricultural systems. Their effects on their host plants are diverse and include volatile ... [more ▼]

Plant growth-promoting rhizobacteria are increasingly considered as a complement of conventional inputs in agricultural systems. Their effects on their host plants are diverse and include volatile-mediated growth enhancement. The present study aims at assessing the effects of bacterial volatile production on the biomass production and the root system architecture of Brachypodium distachyon (L.) Beauv. (line Bd-21). An in vitro experimental set-up allowing plant-bacteria interaction through the gaseous phase without any physical contact was used to screen 19 bacterial strains for their growth promotion ability over a 10-day cocultivation period. Using principal component analysis followed by hierarchical clustering and two-way analysis of variance, five groups of bacteria were defined and characterized based on their combined influence on biomass production and root system architecture. The observed effects range from unchanged to highly increased biomass production coupled with increased root length and branching. Primary root length was only increased by the volatile compounds emitted by Enterobacter cloacae JM22 and Bacillus pumilus T4. Overall, the most significant results were obtained with Bacillus subtilis GB03 which induced a 81% increase in total biomass and enhanced total root length, total secondary root length and total adventitious root length by 88, 196 and 473% respectively. The analysis of the emission kinetics of bacterial volatile organic compounds is underway and should lead to the identification of volatile compounds candidates responsible for the observed growth promotion effects. Taking into account the inherent characteristics of our in vitro system, the next experimental steps are identified and discussed from a fundamental and applied viewpoint. [less ▲]

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See detailOverview and recommendation on urban densification potential in Liège, Belgium
Attia, Shady ULg

in AEE INTEC (Ed.) High-quality retrofit and redensification with timber construction systems (2015, June 18)

Belgium, like many European Countries, has a serious challenge in the housing sector. The Federal planning bureau estimates the increase of population by one million inhabitants by 2030, which represent ... [more ▼]

Belgium, like many European Countries, has a serious challenge in the housing sector. The Federal planning bureau estimates the increase of population by one million inhabitants by 2030, which represent 600.000 additional family requiring accesses to new housing facilities. Population ageing (mainly due to increasing life expectancy) combined with a constant growing rate of individuals living in collective households, leads to a substantial increase of demand of collective households (Vandresse & Bureau, 2013). This highlights a substantial challenge underlined mainly in the need to live in cities, which as consequence will increase the demand for smaller housing with or without integrated services or equipment in common. Furthermore, the stringent European performance environmental regulations for the building sector require that by 2020, all new construction are zero or nearly zero energy, (equivalent to 15 kWh/m2/year), with 60% efficient on-site coverage by renewable energy. The shortage of vacant land and the increasing energy performance requirements is pushing the idea of urban densification and zero energy construction households. During the recent 6 years, there has been a trend to use timber frame constructions as a sustainable solution facing the economic and environmental crisis in Belgium. However, there is lack of knowledge on the design, construction and operation of zero energy lightweight constructions for urban densification. The goal of this research is to provide an overview and recommendation on urban densification potential in Liège Province. The focused aim is to demonstrate validated design prototypes and products of different zero energy, timber frame construction systems and composite components. Thus inform and support the decision making of policy makers, municipalities, developers, and architects and building engineers in Belgium. [less ▲]

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See detailLandscape Control on the Spatial and Temporal Variability of Chromophoric Dissolved Organic Matter and Dissolved Organic Carbon in Large African Rivers
Lambert, Thibault ULg; Darchambeau, François ULg; Bouillon, Steven et al

in Ecosystems (2015)

The characteristics of colored dissolved organic matter (CDOM) as well as the concentrations and stable isotope composition (d 13 C) of dissolved organic carbon (DOC) were characterized in several large ... [more ▼]

The characteristics of colored dissolved organic matter (CDOM) as well as the concentrations and stable isotope composition (d 13 C) of dissolved organic carbon (DOC) were characterized in several large rivers of Africa including the Congo, Niger, Zambezi, and Ogooué basins. We compared the spatial and temporal patterns of dissolved organic matter (DOM) quantity and quality along with various environmental gradients, including hydrology, river size, catchment vegetation, and connectivity to land. The optical proxies used include the absorption coefficient at 350 nm, the specific ultraviolet absorbance, and the spectral slope ratio (S R = 275–295-nm slope divided by 350–400-nm slope). Our results show that land cover plays a primary role in controlling both DOC concentration and optical properties of DOM in tropical freshwaters. A higher cover of dense forest in the catchment leads to a higher quantity of highly aromatic DOM in the river network, whereas an increasing savannah cover results in lower DOC concentrations and less absorptive DOM. In addition to land cover, the watershed morphology (expressed by the average slope) exerts a strong control on DOC and CDOM in tropical rivers. Our results also show that the percentage of C3 and C4 vegetation cover is not an accurate predictor for DOM and CDOM quality in rivers due to the importance of the spatial distribution of land cover within the drainage network. The comparison of our results with previously published CDOM data in temperate and high-latitude rivers highlights that DOM in tropical freshwa-ters is generally more aromatic, and shows a higher capacity for absorbing sunlight irradiance. [less ▲]

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See detailGeorges Ier d’Amboise, amateur d’art
Fagnart, Laure ULg

Conference (2015, June 18)

Figure emblématique de la Renaissance rouennaise et normande, Georges Ier d’Amboise rassemble, on le sait, une bibliothèque exceptionnelle, notamment constituée de manuscrits ayant appartenu aux rois ... [more ▼]

Figure emblématique de la Renaissance rouennaise et normande, Georges Ier d’Amboise rassemble, on le sait, une bibliothèque exceptionnelle, notamment constituée de manuscrits ayant appartenu aux rois aragonais de Naples. Le cardinal s’intéresse également à l’architecture, comme peu de ses contemporains, privilégiant les formes et les fonctions nouvelles, spécialement celles en vigueur en Italie. Il participe aussi à la fortune française d’artistes italiens de renom, comme Andrea Mantegna, Léonard de Vinci, Pérugin ou Andrea Solario, dont il commande ou acquiert des œuvres afin de décorer ses demeures, le château de Gaillon en tête. Mais, alors que son rôle dans la diffusion, au nord des Alpes, des idées et des motifs venus d’Italie est indéniable, le portrait de Georges Ier d’Amboise amateur d’art comprend bien d’autres facettes. Prolongeant une recherche entamée à l’occasion de la parution de l’ouvrage Georges Ier d’Amboise 1460-1510. Une figure plurielle de la Renaissance (2013), cette communication entend revenir sur les objets et les œuvres d’art que l’on peut associer au mécénat et/ou aux possessions de l’archevêque de Rouen. Nous nous pencherons sur les productions italiennes qui sont liées à Georges Ier d’Amboise mais aussi sur les étoffes, les pièces d’orfèvrerie et les tableaux de chevalet, qui sont mentionnés en nombre dans les comptes de dépenses de la construction du château de Gaillon et dans les inventaires qui décrivent les biens meubles conservés dans les demeures du cardinal. L’analyse de ces sources – que jusqu’ici les historiens ont surtout utilisées pour restituer la chronologie du château de Gaillon, rétablir la distribution intérieure de la demeure ou décrire la célèbre bibliothèque du légat alors qu’elles se révèlent extrêmement précieuses pour présenter les collections du conseiller de Louis XII – montre que le goût de Georges Ier d’Amboise, bien que novateur, s’inscrit aussi dans la continuité de celui des amateurs français de la fin du Moyen Âge. [less ▲]

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See detailDes co-enquêteurs coriaces. Quand l'explicitation du travail de terrain complique les choses
Vangeebergen, Thomas ULg

Conference (2015, June 18)

La souplesse et la plasticité des problématiques abordées sont sans doute parmi les attraits majeurs que peuvent présenter les recherches qualitatives. Cette ouverture à une reconfiguration permanente des ... [more ▼]

La souplesse et la plasticité des problématiques abordées sont sans doute parmi les attraits majeurs que peuvent présenter les recherches qualitatives. Cette ouverture à une reconfiguration permanente des questions de recherches réside (entre autres) dans la place que l'on accorde aux acteurs. Plus que des « informateurs », ceux-ci peuvent participer véritablement à l'enquête, et sont alors en fait à la manoeuvre autant que le chercheur. D'acteurs, ils gagnent alors le statut de co-enquêteur. En nous renvoyant nos propres questions, en les reformulant, en les faisant apparaître sous un angle différent, les acteurs contribuent à (re)dessiner nos recherches. [less ▲]

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See detailCharacteristics and implementation of Hybrid Fire Testing (HFT)
Sauca, Ana ULg; Gernay, Thomas ULg; Robert, Fabienne et al

Conference (2015, June 18)

This presentation is dedicated to real time hybrid testing of building members subjected to the action of fire. It will be shown why, whereas pseudo-dynamic testing is possible in other fields, real time ... [more ▼]

This presentation is dedicated to real time hybrid testing of building members subjected to the action of fire. It will be shown why, whereas pseudo-dynamic testing is possible in other fields, real time hybrid testing is the only possible option for the evaluation of fire performance (except, perhaps, for pure metallic unprotected structures). For some structures subjected to fire, the load bearing mechanism in the physical component is completely modified during the test and this modification can take place within a very short period of time. Because of that, the computational demand can be very challenging if the simulated element is simulated in a fully nonlinear computer model, especially if the thermal problem (temperature distribution in the structure) and the mechanical problem have both to be solved within each time step. In order to avoid these difficulties, a possible solution may be to calculate the stiffness matrix that dictates the reaction of the simulated element on the tested element before the test. This matrix can be constant or vary as a function of the displacements measured at the interface during the test. This procedure is very robust but it also has some shortcomings and limitations. The main topic of this paper is the discussion of the advantages and limitations of this procedure applied to hybrid fire testing. A series of three tests which is now under preparation to be performed in the furnace PROMETHEE of CERIB, in France, will also be described in this respect. Preliminary results will be presented if some or all of the tests have been performed at the date of the conference. [less ▲]

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See detailOrigine et dynamique des populations d’arbres des forêts denses humides d’Afrique Centrale, le cas de Lophira alata Banks ex Gaertn C.F. (Ochnaceae)
Biwole, Achille ULg

Doctoral thesis (2015)

The canopy of Central African rainforests is characterized by the abundance of light-demanding trees belonging to several species, suggesting that favorable conditions for their regeneration once ... [more ▼]

The canopy of Central African rainforests is characterized by the abundance of light-demanding trees belonging to several species, suggesting that favorable conditions for their regeneration once prevailed. Today this isn’t the case in light of the demographic structure of their populations, which shows a lack of regeneration. The appearance of such species in rainforests is the result of significant and sustainable openings in the forest canopy. Such events may have occurred with climatic changes and / or large-scale anthropogenic disturbances. The risk of their populations decline is increased by the fact that most of them are timber species. This is typically the case of Lophira alata Banks ex Gaertn C.F., which is one of the most important Central African trees harvested, and is considered vulnerable by the IUCN. In the current context where the preservation of the biodiversity and the integrity of the forest cover is a major concern, the present PhD aims to understand the history and ecological requirements of L. alata in order to propose the sustainable management strategies. The history of L. alata has been studied using an approach integrating both anthracology and archeology. We found a large body of evidences (pottery fragments, palm nuts and charcoal) in the forests soil of southern Cameroon indicating human occupation and widespread fires over two periods : 2200 - 1500 years BP, and around 300 years BP. The age of the most recent events coincides with the probable age of the tallest specimens of L. alata. To determine the light requirements of the species and to better define its regeneration strategy, a quantitative study on the guild of juveniles was conducted for two years. The results show that L. alata has both the characteristics of a pioneer species and those of a non-pioneer species. Indeed, at low irradiances (1% of full sunlight), the plants mortality rate was very low and their biomass showed no signs of decline, a behavior observed in all non-pioneer species. By contrast, the response of leaf traits, patterns of biomass allocation, and the maximum growth of plants in the intermediate (23-43% of the relative irradiance) and high (100%) irradiance levels, according to the population origins, are typical of all pioneer species. These results emphasize the importance of the population origins when studying the response to light and the need to define a more encompassing classification system. In terms of the dynamics of mature populations, environmental conditions affect the diameter growth of trees, with better growth being realized in the evergreen forest. Nevertheless, even under these favorable conditions, simulations of the exploitable stocks and their recovery rates indicated a significant decline during the first three cutting cycles, which could lead to a decline in economic activity associated with this species. Our results allowed us to suggest a set of recommendations for the sustainable management of L. alata. [less ▲]

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See detailPromoting quarries biodiversity through partnerships: a Belgian case study
Seleck, Maxime ULg; Lussis, Benoit; Harzé, Mélanie ULg et al

Conference (2015, June 17)

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected ... [more ▼]

Throughout the life cycle of quarries, a large diversity of temporary habitats is generated, sometimes left to evolve to more permanent ones. In many cases, the biological roles of quarries are neglected though they are playing a significant role as stepping-stones and regulating green infrastructure in landscapes. In highly urbanized and controlled landscapes, quarries are an exceptional opportunity to maintain rare and threatened transient habitats hosting fugitive species. Such ephemeral biodiversity is hard to manage through a site legal protection status. As exploitation progresses, more permanent, biodiverse habitats settle in abandoned areas but the biologic potential could also be maximized by optimized groundwork through the whole exploitation process. Exploitation plans taking into consideration biodiversity could allow maximizing quarry biodiversity hosting capacity during the exploitation phase and in further rehabilitation schemes. In 2012, FEDIEX - the Belgian federation of extractive industries - committed itself to a sectorial charter on “Quarries and Biodiversity”. The charter defines an action plan based on three main axes: i) raising members’ awareness; ii) promoting the integration of practical recommendations for the protection and management of biodiversity in exploitation plans; iii) quarries’ personnel trainings. Since 2012 FEDIEX engaged in a partnership with Gembloux Agro-Bio Tech (University of Liège). Our presentation will trace realizations undertaken under this collaboration, among which the “Mr/Ms Biodiversity” training organized in 2013, 2014 and 2015, the publication of folders popularising the management and enhancement of nature in active quarries and the collaboration in the redaction of a “LIFE in Quarries” project (LIFE Biodiversity) submitted for the 2014 LIFE call. [less ▲]

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See detailLa flexicurité revisitée : analyse qualitative interdisciplinaire du discours de travailleurs à l'aide d'un logiciel collaboratif »
Beuker, Laura ULg; DE CIA, Julie ULg; Orianne, Jean-François ULg et al

Conference (2015, June 17)

La flexicurité constitue un oxymore qui prône la recherche d’un équilibre entre besoins de flexibilité et de sécurité sur le marché du travail. Cet équilibre est avant tout un objectif politique, mais il ... [more ▼]

La flexicurité constitue un oxymore qui prône la recherche d’un équilibre entre besoins de flexibilité et de sécurité sur le marché du travail. Cet équilibre est avant tout un objectif politique, mais il reste fragile aux yeux des acteurs concernés. En cherchant à croiser le regard analytique de trois disciplines – psychologie, gestion et sociologie –, nous avons recouru au logiciel Cassandre (Lejeune, 2008) pour dégager des tensions discursives autour des notions de flexibilité et de sécurité dans un corpus de vingt entretiens qualitatifs. L’article permet ainsi de concrétiser l’intérêt et les limites de l’utilisation d’un logiciel d’analyse qualitative dans le cadre d’un travail interdisciplinaire. [less ▲]

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See detailAdvanced characterisation to investigate the effect of raw material properties on the kinetics of iron ores granulation
Jaimes Contreras, Rafael Antonio; van Loo, Frédéric; Douce, Jean-François et al

Speech/Talk (2015)

The objective of this paper is to study the effect of raw material properties on the kinetics of iron ore granulation considering in particular the layering mechanisms in wet granulation for different ... [more ▼]

The objective of this paper is to study the effect of raw material properties on the kinetics of iron ore granulation considering in particular the layering mechanisms in wet granulation for different iron ore types. For that purpose, the granulation behaviour of single iron ore binary mixtures and more complex mixtures (iron ores and return fines) has been studied at laboratory scale using pilot drums. A particular interest is paid to the influence of morphology and wettability of iron ores. [less ▲]

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See detailUse of 16S rDNA Metagenetics and classical Microbiology to Assess the bacterial superficial Contamination Patterns in Bovines Classically Slaughtered or following the Halal Ritual
Korsak Koulagenko, Nicolas ULg; Taminiau, Bernard ULg; Hupperts, Caroline et al

Poster (2015, June 17)

In Belgium and in several European countries, two cattle slaughtering protocols exist: the classical method, that encompasses a stunning step before the sticking procedure, and the halal method, combining ... [more ▼]

In Belgium and in several European countries, two cattle slaughtering protocols exist: the classical method, that encompasses a stunning step before the sticking procedure, and the halal method, combining the stunning and the sticking in one single step. The main difference lies in the fact that, in the halal protocol, a single cut with a sharp knife is practiced directly on live cattle, instead of two cutting steps with two different knives for the sticking in the classical slaughtering technique. The unique section in the halal technique results generally in the cross section of trachea and esophagus of cattle. The aim of this study was to seek if the two slaughtering techniques were similar regarding the superficial contamination of carcasses, swabbed between 2 and 4 hours after the killing step. For this purpose, classical microbiological tests (TVC and Enterobacteriaceae) and 16S rDNA metagenetic analysis were carried out from 20 cattle carcasses (swabbing of “legal” zone – 1.600 cm2 – and in the neck area – 200 cm2). The classical microbiological results revealed no significant differences between the two slaughtering practices. Statistical analysis of pyrosequencing data showed that differences in bacterial population abundance between slaughtering methods were mainly found in the “legal” swabbing zone compared to the neck area. Bacterial genera belonging to Actinobacteria (Brevibacterium, Corynebacterium) were more aundant in “Halal” samples whereas populations from the Proteobacteria (Caulobacteraceae, Comamonadaceae, Bradyrhizobiaceae) and Firmicutes (Lactobacillus) were more abundand in the “classical” group. The analysis of OTU abundance of bacteria from the digestive or respiratory tract revealed no differences beteween groups. In conclusion, the slaughtering method does not influence the superficial microbiological pattern in terms of specific microbiological markers of the digestive or respiratory tract. However, precise analysis to the genus level underlines differences between methods, the legal swabbing zone being still the best sampling zone compared to the neckline. The next step will be the identification of precise contamination origin of the differences found between slaughtering methods. [less ▲]

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See detailMAVEN IUVS observations of the aftermath of the Comet Siding Spring meteor shower on Mars
Schneider, Nick; Deighan, Justin; Stewart, Ian et al

in Geophysical Research Letters (2015)

We report the detection of intense emission from magnesium and iron in Mars' atmosphere caused by a meteor shower following Comet Siding Spring's close encounter with Mars. The observations were made with ... [more ▼]

We report the detection of intense emission from magnesium and iron in Mars' atmosphere caused by a meteor shower following Comet Siding Spring's close encounter with Mars. The observations were made with the Imaging Ultraviolet Spectrograph, a remote sensing instrument on the Mars Atmosphere and Volatile EvolutioN spacecraft orbiting Mars. Ionized magnesium caused the brightest emission from the planet's atmosphere for many hours, resulting from resonant scattering of solar ultraviolet light. Modeling suggests a substantial fluence of low-density dust particles 1–100 µm in size, with the large amount and small size contrary to predictions. The event created a temporary planet-wide ionospheric layer below Mars' main dayside ionosphere. The dramatic meteor shower response at Mars is starkly different from the case at Earth, where a steady state metal layer is always observable but perturbations caused by even the strongest meteor showers are challenging to detect. [less ▲]

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