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See detailCHARACTERIZATION OF THE KABYLE BREED OF HEN (THAYAZIT LEKVAYEL) AND ITS FARMING SYSTEM IN THE REGION OF CHEMINI AND BOUZEGUENE (ALGERIA)
Moula, Nassim ULg

in INTERNATIONAL CONFERENCE Agriculture Development in the Context of International Integration: Opportunities and Challenges (2016, December 07)

The rural poultry in Algeria is a supplier of popular products. The aims of this study are to characterize local chickens in Kabylie in terms of the livestock practices, management, flock structures, uses ... [more ▼]

The rural poultry in Algeria is a supplier of popular products. The aims of this study are to characterize local chickens in Kabylie in terms of the livestock practices, management, flock structures, uses, performance and phenotypes. The present survey addresses this issue in the case of Kabylie, a mountainous coastal region of Algeria, and concerns 28 households raising poultry and a morpho - biometric description of 388 (290 females and 98 males) adult local chickens. The farming practices is characterized by a reduction in the time allocated for this activity and to deal with production costs which are aspects of an unproductive extensive livestock system considered as a secondary activity. The body weight is 2.03 ± 0.22 kg and 1.61 ± 0.19 kg respectively in the male and the female. The age at first egg, egg weight, egg production per hen per clutch, number of clutches per year, hatchability and number of chicks weaned are 28.00 ± 3.82 weeks, 49.03 ± 3.66 g, 13.57 ± 1.64, 3.82 ± 1.14, 89.29 ± 9.79% and 7.82 ±1.75 respectively. The comb type is mostly single (89.43%). Skin colours are principally white (39.18%) and yellow (39.43). The comb and wattles are mostly red (93.30). Shanks colours are principally yellow (49.74%) and white (24.23%). The most common plumage colours are salmon (14.43%), white (12.11%), black (17%), grey (9.54%) and gold (9.02%). The genetic improvement of local poultry breeds is also to consider, provided that the suitability of the animal with respect to the context of its breeding is preserved. [less ▲]

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See detailIntroduction du Dossier de traduction
Borotto, Jessica ULg; Cavazzini, Andrea

in Cahiers du GRM (2016), 10

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See detailBrisons le système, pouvoir aux femmes ! (Padoue, 1974)
Borotto, Jessica ULg

in Cahiers du GRM (2016), 10

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See detailRésister à l’essentialisation de l’Allemagne : Les Temps Modernes, revue franco-allemande ?
Franck, Thomas ULg

in Trajectoires (2016), 10

Im Zentrum des vorliegenden Aufsatzes steht die Doppelausgabe (46-47) der französischen Zeitschrift Temps Modernes, die unter dem Titel „Allemagne“ im August-September 1949 erschien und einen besonderen ... [more ▼]

Im Zentrum des vorliegenden Aufsatzes steht die Doppelausgabe (46-47) der französischen Zeitschrift Temps Modernes, die unter dem Titel „Allemagne“ im August-September 1949 erschien und einen besonderen Fall von kulturellem und intellektuellem Transfer zwischen Deutschland und Frankreich darstellt. Mit Mitteln der Diskursanalyse und der Imagologie sollen hier rhetorische Strategien herausgearbeitet werden, die der Realisierung eines kritischen Projekts und der Anprangerung der Stereotypen dienen, die Deutschland damals zugeschrieben wurden. Aufgestellt wird folgende These: Indem sie Intellektuelle aus unterschiedlichen Orten und Disziplinen und heterogenes Wissen zusammenbringt, bietet sich die Zeitschrift besonders gut für eine kritische Reflexion der herrschenden Ideologien und kollektiven Überzeugungen an. Indem es Deutschen mit kommunistischer und antifaschistischer Gesinnung das Wort erteilt, will das Heft „Allemagne“ zu Erkenntnissen über ein ‚anderes Deutschland‘ kommen, das von Aufstand und Widerstand geprägt ist, und bricht so mit einer Reduktion des Landes auf eine unveränderliche und monolithische Identität, die als gleichermaßen fügsam und autoritär verstanden wurde. [less ▲]

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See detailIn vitro evaluation of biocompatibility of uncoated thermally reduced graphene and carbon nanotube-loaded PVDF membranes with adult neural stem cell-derived neurons and glia
Defteralı, Çağla; Verdejo, Raquel; Majeed, Shahid et al

in Frontiers in Bioengineering and Biotechnology (2016), 4(n° 64),

Graphene, graphene-based nanomaterials (GBNs), and carbon nanotubes (CNTs) are being investigated as potential substrates for the growth of neural cells. However, in most in vitro studies, the cells were ... [more ▼]

Graphene, graphene-based nanomaterials (GBNs), and carbon nanotubes (CNTs) are being investigated as potential substrates for the growth of neural cells. However, in most in vitro studies, the cells were seeded on these materials coated with various proteins implying that the observed effects on the cells could not solely be attributed to the GBN and CNT properties. Here, we studied the biocompatibility of uncoated thermally reduced graphene (TRG) and poly(vinylidene fluoride) (PVDF) membranes loaded with multi-walled CNTs (MWCNTs) using neural stem cells isolated from the adult mouse olfactory bulb (termed aOBSCs). When aOBSCs were induced to differentiate on coverslips treated with TRG or control materials (polyethyleneimine-PEI and polyornithine plus fibronectin- PLO/F) in a serum-free medium, neurons, astrocytes, and oligodendrocytes were generated in all conditions, indicating that TRG permits the multi-lineage differentiation of aOBSCs. However, the total number of cells was reduced on both PEI and TRG. In a serum-containing medium, aOBSC-derived neurons and oligodendrocytes grown on TRG were more numerous than in controls; the neurons developed synaptic boutons and oligodendrocytes were more branched. In contrast, neurons growing on PVDF membranes had reduced neurite branching, and on MWCNTs-loaded membranes oligodendrocytes were lower in numbers than in controls. Overall, these findings indicate that uncoated TRG may be biocompatible with the generation, differentiation, and maturation of aOBSC-derived neurons and glial cells, implying a potential use for TRG to study functional neuronal networks. [less ▲]

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See detailWhy and how to repair concrete? Compatibility assessment
Courard, Luc ULg

Scientific conference (2016, December 06)

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See detailSocialisation et articulation des régimes d'historicités
Grandjean, Geoffrey ULg

Conference given outside the academic context (2016)

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See detailDynamic Modeling of Organic Rankine Cycle Power Systems
Desideri, Adriano ULg

Doctoral thesis (2016)

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See detailBerge-acyclic multilinear 0-1 optimization problems
Buchheim, Christoph; Crama, Yves ULg; Rodriguez Heck, Elisabeth ULg

E-print/Working paper (2016)

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See detailEvaluation des impacts des projets de développement sur les exploitations agricoles familiales et les ménages de l’ATACORA (Nord-Ouest du Benin)
Tohinlo, Yecy ULg

Doctoral thesis (2016)

This doctoral research aims to contribute to a better understanding of the effects of development projects on the improvement of living conditions and livelihoods of rural households in Benin. It begins ... [more ▼]

This doctoral research aims to contribute to a better understanding of the effects of development projects on the improvement of living conditions and livelihoods of rural households in Benin. It begins with the analysis of development trends in Atacora known about the last three decades. It is focused on matching between the dynamics promoted by intervention devices and those endogenous or emerging to lead a part in the consideration of the productive trajectories and performance of family farms and also in the analysis of effects of development projects on food security, living standards and poverty of rural households. The post-development theories and the various conceptions of poverty have served as a guideline for research work. The intervention mechanisms conducted in Atacora (north-western Benin) by the various cooperations (bilateral and multilateral) between 1990 and 2010 constituted the research object of this thesis. The empirical phase took place in the communes of Cobly (West) and Péhunco (East). These communes were selected from their contrasting agro-ecological and socio-economic situations and socio-economic indicators on the one hand and on the other on a typology of the concentration of development projects and the perception of their effects by local people. A stratified sample of 344 households (respectively 214 in Cobly and 130 in Péunco) was formed for the characterization survey. Later, a thorough investigation on living conditions and livelihood of households followed and involved 208 households (129 Cobly; 79 Péhunco). Finally 16 case studies (8 per commune) were conducted on the trajectories of evolution and accumulation of property and wealth of households and farms. Due to the empirical research, special attention was given to primary data collection which lasted more than three (3) years. Qualitative and quantitative tools (including PSM) were combined for the analysis of collected data through individual and group interviews. Results show that the development interventions do not always promote the endogenous dynamics but they generate and maintain, in rural areas, pathways that allow the integration and participation of producers in the world market for agricultural products. And to benefit from various promotional activities, producers adopt supported crops, this have some positive and negative consequences. The integration and participation of rural producers of Atacora to international trade, promote the increase of production and crop yields while further increasing their dependence on the world prices of agricultural products. So while the income of producers is increasing their vulnerability to food insecurity is also increasing because many of the food crops, already insufficient (because of the share of the cotton planted and the cotton production quotas established by the government) to cover food needs, are substracted from consumption to be sold on the market to meet urgent liquidity needs. Thereby, Atacora's rural households, despite the increase of their food production, suffered a rupture of food stocks resulting to annual food crises of at least 4 months (16 weeks) which strikes indiscriminately both recipient households than non-project beneficiaries. However with the increase of sources and income level of recipient households (36% of households of the study sites), those beneficiaries improve their homes and food consumption and invest more in the education of their children. This marks a significant difference between beneficiaries and non-beneficiaries of development projects. Indeed, installed with the same resources, we counted, in 2014, twice more prosperous households and fewer poor among beneficiaries than non-beneficiaries. Furthermore farms and households beneficiaries of assistance have accumulated and hold more productive assets (land, farm equipment, livestock rearing), economic assets and holdines (transportation measures, housing, plots and houses to rent, etc.) than non-beneficiaries with a highly significant difference at 1%. However the level of improvements and living conditions induced by development interventions are still inadequate and insecure, as reduced to the equivalent adult,income as well as capital show no significant difference between beneficiaries and non-beneficiaries. Thus, households (even beneficiaries) remain vulnerable to crises so that any natural disaster (flood, drought, pest invasion, etc.), illness, injury and death of a member of the household, provokes the rapid degradation of living standards and the fall into poverty. This is compounded by the fact that farms owners’ don’t invest really in the restoration and enhancement of the capital '' land fertility ''; mainly in Cobly where the soil fertility level experienced a drastic decline with a consequent increasing use of chemical fertilizers that degrade the soil structure furthermore. It follows that any action aimed at poverty reduction should allow a sustainable improvement in conditions and livelihoods of rural producers by the preservation and restoration of soil fertility on the one hand and the increased resilience to crises on the other hand. Actions to identify specific needs with measures and solutions adapted to each category of producers and households with mainly particular mechanisms of management and restoration of the fertility of agricultural land shall be considered and implemented. [less ▲]

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See detailL'Afrique centrale: entre traditions et transitions. La mutation des socio-écosystèmes en Afrique centrale
Gillet, Pauline ULg

Doctoral thesis (2016)

The forests of the Congo Basin are among the best preserved areas on Earth. Nevertheless, the factors causing deforestation around the world are also present in this subregion. The forest transition ... [more ▼]

The forests of the Congo Basin are among the best preserved areas on Earth. Nevertheless, the factors causing deforestation around the world are also present in this subregion. The forest transition theory describes how the trend of forest areas decline at national level may precede an increase in these areas. If the effects of the forest transition are well known in terms of forest cover degradation, little is known about the effects of forest transition on socio-ecosystems (SES) (understood as a group of actors with impacts on a group of resources and subject to specific institutions). The general objective of this thesis is to characterize the mutation of socio-ecosystems in the Congo Basin in order to identify dynamic of change of Congo Basin forested SES and their possible futures. The collection of socioeconomic data, focusing on the description of the population, the description of the different activities and incomes, the description of food intake and the access to land and resources, were conducted in three SES with a forest cover gradient, located in Cameroon and Gabon. The results show that the cost price of meals is globally increasing with the loss of forest cover. The share of food intake related to the exploitation of natural resources such as hunting, fishing and gathering decreases in favor of proteins from livestock and agricultural products. This leads to the translocation of demand but also to pressures on other anthropogenic ecosystems. The effects of deforestation are then visible at the local level but also on neighboring areas. The diversity of the game and prey decreases moving towards smaller species with the progression of the forest transition. Consequently, there is a reduction in the proportion of these products in both the food intake and household incomes. This analysis shows a decline in the importance of NTFPs in the production and villagers livelihoods. Slash and burn agriculture is practiced in three SES. If the ratio between fallow period and cultivation period decreases with the forest transition, there is an increase in crop diversification leading to a diversification of the diet. Access to forest resources, agricultural land, markets and an external source of employment condition the village activities. The land potential is made to report levels of ownership and co-management of customary space (Le Roy et al., 1996). During the progression of the forest transition curve, the land potential evolves from relatively loose to privatization and the ability to alienate resources. These important modifications of traditional control systems of the relations between man and resources lead to a more adequate management of some commercial resources value (such as agricultural products or mining resources). But, this process is incompatible with the maintenance of certain ecosystem services like large populations of wildlife preservation. If these results fit rather well with the forest transition curve, this is not the case of all SES in Central Africa. Therefore, we propose to combine some results to reflect significant changes of the qualities of a socio-ecosystem, regardless of forest cover rate. The priority would be to establish a standardized data collection protocol to test sites with different forest cover and located on different trajectories. The use of a socio-economic index would make it possible to predict the evolution of SES under different scenarios, whether linked to global or regional pressures (such as the emergence plans enacted by the Central African States) or in contexts of economic crisis or the introduction of new legislation. [less ▲]

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See detailSpace Thermal Analysis through Reduced Finite Element Modelling
Jacques, Lionel ULg

Doctoral thesis (2016)

The finite element method (FEM) is widely used in mechanical engineering, in particular for structure design. However, it is not often exploited for the thermal analysis of space structures for which the ... [more ▼]

The finite element method (FEM) is widely used in mechanical engineering, in particular for structure design. However, it is not often exploited for the thermal analysis of space structures for which the use of the lumped parameter method is still commonplace. To alleviate the computational burden of the FEM for thermal analyses involving conduction and radiation, an innovative global conductive-radiative reduction scheme based on the clustering of the finite element mesh is presented. The proposed method leads to a significant reduction of the number of radiative exchange factors (REFs) to compute and size of the corresponding matrix. It further keeps accurate conduction information by introducing the concept of physically meaningful super nodes associated to the clusters from which are derived the reduced conductive couplings. To complement the reduction of the number of faces, an improved Monte Carlo ray tracing algorithm is developed. It provides better accuracy and convergence rate than the classic Monte Carlo method. The algorithm is adapted to the partitioned FE mesh and includes quadrics fitting for accurate normal representation. The resulting conductive-radiative reduced model is solved using standard iterative techniques and the detailed mesh temperatures, recovered from the super nodes temperatures, can be directly exploited for thermo-mechanical analysis. The proposed global reduction method is validated on several space structures and is benchmarked against ESATAN-TMS, the standard thermal analysis software used in the European aerospace industry. [less ▲]

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See detailDevelopment and analysis of low-order models of frame structures under blast loads
Hamra, Lotfi ULg

Doctoral thesis (2016)

The main aim of this thesis is to propose an easy-to-apply tool to assess the level of damage of a structure in which one compartment is subjected to blast loading. This compartment is extracted from the ... [more ▼]

The main aim of this thesis is to propose an easy-to-apply tool to assess the level of damage of a structure in which one compartment is subjected to blast loading. This compartment is extracted from the structure accounting for the interaction with the part of the structure surrounding the loaded compartment, which is assumed to be elastic. Before studying the whole frame structure, the structural elements (i.e. the beam and its adjacent columns) are firstly studied separately taking into account the lateral restraint and mass offered by the indirectly affected part (IAP) of the structure. Secondly, the dynamic behaviour of a simple compartment made of pinned members and laterally braced is investigated. The material laws are assumed to be elastic-perfectly plastic, neglecting the effect of strain rate on the yield strength. The out-of-plane instabilities of the structural members are disregarded. • To explain the context of this study + final aim of this research Two analytical models are developed to predict the dynamic response of the frame beam subjected to blast loading, including the elastic lateral restraint and inertia offered by the IAP of the structure, the development of nonlinear membrane action (P-\delta effect) and also, the interaction between bending moment and axial force in the plastic hinges. The first model is based on a single degree of freedom (SDOF model) which is the transverse mid-span deflection of the beam while the second model is a two-degree-of-freedom (2-DOF) model which also includes the axial elongation of the beam. The accuracy of these two low-order models is assessed with finite element simulations. This validation stage shows that the proposed low-order models capture the physics of the problem in most cases of practical interest. A dimensional analysis of the problem reveals that, under the considered assumptions, four dimensionless parameters mainly influence the required ductility of the beam. Two of them are related to the behavior of the indirectly affected part (the lateral restraint and mass). Another one is related to the mechanical properties of the investigated beam (i.e. the ratio of the bending to axial resistance). The last parameter incorporates scales of the geometry and of the deformed configuration at the onset of the plastic mechanism. Concerning the columns, an analytical model is proposed to assess its dynamic response under constant axial compressive load and lateral blast loading. It accounts for large displacement (P-\delta effect), bending moment-axial force (M-N) plastic interaction as well as its interaction with the indirectly affected part (IAP) of the structure. This model is non-smooth piecewise linear and involves two degrees of freedoms (2 DOFs) in each regime of the motion of the column (related to the possibilities of development of plastic hinges). The dimensional analysis of the problem reveals that, under the considered assumptions, four dimensionless parameters mainly influence the dynamic stability of the beam-column. Two of them are related to the behavior of the indirectly affected part (the lateral restraint and mass). Another one is related to the critical load multiplier (i.e. the ratio of the axial compressive load to Euler elastic buckling resistance). The last parameter is the reduced slenderness of the beam-column. Subsequent to a parametric study, it is demonstrated that a good correlation is found between the results provided by the analytical model and a richer FEM model, despite some little discrepancies observed for some intermediate values of stiffness of the lateral restraint and lateral mass. As a possible improvement, adjustments to the analytical model are suggested. Finally, the dynamic behaviour of a simple frame under constant compressive loads and lateral blast loading is studied with a last 2-DOF analytical model. A multi-layer model of the cross-section of the beam is used to derive the bending moment-axial force (M-N) plastic interaction instead of the Lescouarc'h formula and normality rule. The coupling between the beam and the adjacent columns is ensured through appropriate boundary conditions. For the studied frame, two blast scenarios are contemplated, the first one corresponds to a quasi-static blast loading while the second one refers to a dynamic blast loading. The first case study shows that a very good agreement is achieved between the deflections predicted by the analytical and numerical models although a discrepancy is observed in the assessment of the axial force in the column due to the shape of the inertial force distribution of the beam assumed in the model. The second case study illustrates that, in both analytical and numerical models, the columns are predicted to fail by buckling due to the P-\delta effect although the axial force in the column is again inaccurately captured by the analytical model for the same reason. [less ▲]

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See detailLa nostra «avvelenata» (Guccini non ne ha colpa)
Curreri, Luciano ULg; Belletti, Gabriele

Article for general public (2016)

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See detailLarge neighborhood search for multi-trip vehicle routing
François, Véronique ULg; Arda, Yasemin ULg; Crama, Yves ULg et al

in European Journal of Operational Research (2016), 255(2), 422-441

We consider the multi-trip vehicle routing problem, in which each vehicle can perform several routes during the same working shift to serve a set of customers. The problem arises when customers are close ... [more ▼]

We consider the multi-trip vehicle routing problem, in which each vehicle can perform several routes during the same working shift to serve a set of customers. The problem arises when customers are close to each other or when their demands are large. A common approach consists of solving this problem by combining vehicle routing heuristics with bin packing routines in order to assign routes to vehicles. We compare this approach with a heuristic that makes use of specific operators designed to tackle the routing and the assignment aspects of the problem simultaneously. Two large neighborhood search heuristics are proposed to perform the comparison. We provide insights into the configuration of the proposed algorithms by analyzing the behavior of several of their components. In particular, we question the impact of the roulette wheel mechanism. We also observe that guiding the search with an objective function designed for the multi-trip case is crucial even when exploring the solution space of the vehicle routing problem. We provide several best known solutions for benchmark instances. [less ▲]

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See detailL'art de gouverner les déchets hautement radioactifs. Analyse comparée de la Belgique, la France et le Canada
Parotte, Céline ULg

Doctoral thesis (2016)

Comment l'art de gouverner les déchets hautement radioactifs, tel qu'il a évolué au cours des deux dernières décennies, a-t-il redéfini les enjeux sociotechniques du programme de gestion des déchets ... [more ▼]

Comment l'art de gouverner les déchets hautement radioactifs, tel qu'il a évolué au cours des deux dernières décennies, a-t-il redéfini les enjeux sociotechniques du programme de gestion des déchets hautement radioactifs et réciproquement? Telle est la question qui traverse cette thèse. Combinant l'analytique de gouvernement (Dean 2010) à une approche co-productionniste forte (Joly 2015), trois régimes de pratiques de gouvernement, en France, en Belgique et au Canada sont scrutés et comparés. Cet écrit propose de suivre l'objet, en cinq chapitres, depuis sa définition (au travers des systèmes de classification), en passant par l’élaboration, la mise en oeuvre territoriale et l'évaluation régulière de son programme de gestion. Chemin faisant, nous cherchons à comprendre comment le dépôt géologique est resté l’option de référence clef pour la catégorie "déchet hautement radioactif". Différentes co-productions seront mises à jour révélant l'asymétrie de pouvoir entre les acteurs, la trajectoire (dis)continue du programme et le caractère expérimental de l’art de gouverner les déchets hautement radioactifs. Un art expérimental, dont nous soutenons que les formes peuvent varier, entre autres, selon l'attitude des expérimentateurs. [less ▲]

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See detailReplication Errors Made During Oogenesis Lead to Detectable De Novo mtDNA Mutations in Zebrafish Oocytes with a Low mtDNA Copy Number.
Otten, Auke B. C.; Stassen, Alphons P. M.; Adriaens, Michiel et al

in Genetics (2016), 204(4), 1423-1431

Of all pathogenic mitochondrial DNA (mtDNA) mutations in humans, ~25% is de novo, although the occurrence in oocytes has never been directly assessed. We used next generation sequencing to detect point ... [more ▼]

Of all pathogenic mitochondrial DNA (mtDNA) mutations in humans, ~25% is de novo, although the occurrence in oocytes has never been directly assessed. We used next generation sequencing to detect point mutations directly in the mtDNA of 3-15 individual mature oocytes and three somatic tissues from eight zebrafish females. Various statistical and biological filters allowed reliable detection of de novo variants with heteroplasmy >/=1.5%. In total, we detected 38 de novo base substitutions, but no insertions or deletions. These 38 de novo mutations were present in 19 of 103 mature oocytes, indicating that ~20% of the mature oocytes carry at least one de novo mutation with heteroplasmy >/=1.5%. This frequency of de novo mutations is close to that deducted from the reported error rate of polymerase gamma, the mitochondrial replication enzyme, implying that mtDNA replication errors made during oogenesis are a likely explanation. Substantial variation in the mutation prevalence among mature oocytes can be explained by the highly variable mtDNA copy number, since we previously reported that ~20% of the primordial germ cells have a mtDNA copy number of </=73 and would lead to detectable mutation loads. In conclusion, replication errors made during oogenesis are an important source of de novo mtDNA base substitutions and their location and heteroplasmy level determine their significance. [less ▲]

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