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See detailDissensus, n°7. Dossier "Technique et politique" (Edition en cours)
Pieron, Julien ULg

Book published by PoPuPS (2014)

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See detailBook Review: Ralf Brand and Sarah Fregonese 2013: The Radicals’ City: Urban Environment, Polarisation, Cohesion. Surrey: Ashgate.
Farah, Jihad ULg

in International Journal of Urban and Regional Research (2014), 38(6),

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See detailLes forces de la négation dans l’image
Dondero, Maria Giulia ULg

in Acquarelli, Luca (Ed.) Au prisme du figural. Le sens des images entre forme et force (2014)

Ce texte vise à décrire un type particulier de forces inhérentes à la configuration de l’image. Il s’agit de forces qui mettent en crise la figuration et le caractère affirmatif de l’image, en les ... [more ▼]

Ce texte vise à décrire un type particulier de forces inhérentes à la configuration de l’image. Il s’agit de forces qui mettent en crise la figuration et le caractère affirmatif de l’image, en les détournant et en les rendant « hésitants ». Nous souhaitons démontrer que l’image n’est pas contrainte d’affirmer ce qu’elle met en scène : elle a également la capacité de le nier. La négation par l’image représente à nos yeux un défi majeur pour les sémioticiens du visuel et les théoriciens de l’art, notamment dans le cadre de recherches sur le langage de l’image, le métalangage visuel et, plus généralement, sur les capacités de l’image à développer un discours autonome par rapport au discours verbal [less ▲]

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See detailRecyclage des briques cassées pour améliorer les propriétés céramiques des argiles plastiques (Meknès, Maroc)
El Ouahabi, Meriam ULg; Daoudi, Lahcen; El Boudour El Idrissi, Hicham ULg et al

Poster (2014, October 27)

Dans le Bassin de Saïs (nord ouest du Maroc), les argiles du Miocène de la région de Meknès sont utilisées dans l’industrie céramique locale pour la fabrication des briques. Ces argiles riches en smectite ... [more ▼]

Dans le Bassin de Saïs (nord ouest du Maroc), les argiles du Miocène de la région de Meknès sont utilisées dans l’industrie céramique locale pour la fabrication des briques. Ces argiles riches en smectite et en carbonates, ont une granulométrie très fine, marquée par la quasi absence de la fraction sableuse. Ces propriétés les rendent très plastiques, ce qui engendre des taux de retrait importants au séchage et à la cuisson et des problèmes de qualité du produit fini qui s’en suivent (fissurations, déformations et casses pendant les processus de séchage et de cuisson). Dans le but de palier à ce problème et d’améliorer la qualité du produit fini, nous proposons au cours de cette étude de recycler les déchets de briques cassées. Afin d'atteindre ces objectifs, 4 formulations ont été réalisées à base d’argiles plastiques, riches en smectite et des casses de briques broyées. Des quantités de 5, 10, 15 et 20% de briques broyées ont été ajoutées à la pâte destinée à la confection des briques. Des analyses minéralogiques par diffraction des rayons X (DRX), chimiques par spectrométrie de fluorescence (XRF), granulométrique par granulométrie laser, ainsi que les limites d’Atterberg ont été effectuées. Les résultats minéralogiques montrent une diminution de la teneur en carbonates (calcite) et en argile totale (principalement smectite), lors des ajouts successifs de briques broyées. La fraction sableuse augmente progressivement, jusqu’à atteindre 30% pour une formulation avec 20% de casses de briques. Cette granulométrie plus grossière diminue la plasticité de la pâte et permet d’éviter les déformations et les fissures pendant le processus du séchage. De plus, l’ajout des casses de briques dilue les carbonates, ce qui permet d’améliorer la qualité du produit cuit. Ces résultats indiquent que le recyclage des déchets de briques, présente un intérêt à la fois économique et écologique. Des essais de comportement au séchage et à la cuisson ainsi que des essais mécaniques complèteront cette étude. [less ▲]

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See detailUTILISATION DES RESIDUS DE LAVAGE DES GRANULATS DE CARRIERES DANS L’ELABORATION DE PIECES CERAMIQUES (REGION DE TAMAZOUZT, MAROC).
El Boudour El Idrissi, Hicham ULg; Daoudi, Lahcen; El Ouahabi, Meriam ULg et al

Conference (2014, October 27)

Le site potier de Tamazouzt est situé à 40 km au Sud-Est de la ville de Marrakech. La production est sous forme de poterie décorative d’ustensiles rustiques. La matière première utilisée dans ... [more ▼]

Le site potier de Tamazouzt est situé à 40 km au Sud-Est de la ville de Marrakech. La production est sous forme de poterie décorative d’ustensiles rustiques. La matière première utilisée dans l’élaboration de ces produits est issue de résidus de lavage des carrières de granulats exploités le long des oueds. En plus de la qualité des produits et des rendements élevés, ce site donne un bon exemple de valorisation des résidus de lavage qui causent des problèmes pour l’environnement et pour les industriels. Nous avons caractérisé cette matière première afin d’en faire la promotion et d’encourager l’exploitation de tels matériaux dans le domaine de la céramique à l’échelle globale. Les résultats des analyses montrent que la pâte est constituée de 62% d’argiles, 23% de limons et 15% de sables ; l’indice de plasticité est de l’ordre de 16. Pour 27% d’humidité, le degré de retrait au séchage ne dépasse pas 6%. La minéralogie indique la présence de quartz (32%), plagioclase (20%), feldspaths potassiques (10%), calcite (3%) et argile (31%). Les minéraux argileux sont constitués d’illite (16%), de chlorite (7%), de kaolinite (4%) et de vermiculite (4%). La teneur en matière organique est de 4%. La composition chimique est surtout silico-alumineuse (64% de SiO2, 17% d’Al2O3). Les autres éléments majeurs dont la teneur est significative (> 1%) sont : Fe2O3 (8%), MgO (4%), K2O (3%), CaO (3%), Na2O (2%). Les pièces cuites à 1050°C présentent 2% de retrait, 13% de porosité à l’eau, la résistance mécanique à la compression et à la flexion est respectivement de 63 et 20 Mpa. L’analyse DRX des pièces cuites à 1050°C a montré l’apparition de géhlénite, anorthite, diopside et d’hématite. Ces résultats indiquent qu’en plus de l’utilisation locale dans la poterie décorative ces argiles pourraient être valorisées comme matériaux de construction vue leur caractère isolant (bonne porosité), résistance (bon comportement mécanique) et leur couleur rouge (présence de l’hématite). [less ▲]

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See detailModelling serial offenders’ spatial behaviours: new assumptions for geographic profiling
Trotta, Marie ULg

Doctoral thesis (2014)

The geographic profiling is amethodology of investigation which uses the crime sites of a criminal series in order to delineate prior areas for searching the offender. Its implementation is currently ... [more ▼]

The geographic profiling is amethodology of investigation which uses the crime sites of a criminal series in order to delineate prior areas for searching the offender. Its implementation is currently limited by too simplistic assumptions that are difficult to assess during an investigation or even not corroborated at an individual level of observation. This thesis studies the predictive capacities of geographic profiling in the context of Belgium, a dense country where the road network is not suitable for classical algorithmimplemented with Euclidean or Manhattan distances. More precisely, the thesis has for first objective to integrate space anisotropy with two improvements: (1) the integration of the road network in the journey-to-crime and (2) the integration of the structure of opportunities for series of sexual offences. Beyond this objective, the thesis questions a hypothesis underlying this type of research methodology: the kind of spatial relationship between the offender’s residence and the crime sites. An alternative to the distance decay effect is developed, minimising the variance in travelled distances between the offender anchor point and the initial contact sites of the offences (MOV hypothesis). The sensitivity of this methodology is measured and its effectiveness is compared to the one of the distance decay effect. A major result of the thesis is that the share of behaviours than can be modelled by this new hypothesis is similar to the one of the distance decay effect. However, a large number of series did not meet the required conditions to implement an efficientmethodology given the multiplicity of offender’s residences or the scarcity of sites composing the series; those applicability criteria are analysed in this work. Nevertheless, theMOV hypothesis is particularly valuable for long series of offences. Then, the thesis analyses the impact of the geometry of crime series locations on the effectiveness of the chosen spatial assumption (distance decay effect orMOV) with graph theory. It highlights the superiority of the MOV hypothesis for offenders travelling in some preferred direction. The analysis also shows that both hypotheses are not mutually exclusive but can be combined to build offender geographic profiles. Finally, this thesis focuses on the modelling of neutral areas in terms of criminal attractiveness on the Belgian territory. The work presents the originality of analysing data on a whole country, integrating both urban and non-urban areas. The objective of the modelling is the integration of the opportunity structure of sexual offences in the geographic profile and the estimation of the perturbing effect of a differentiated attractiveness. In order to assess this perturbation, we propose a two-steps process. Firstly, a regression model combining factors fromthe crime pattern and social disorganisation theories models the spatial distribution of crimes. The regression model identifies a centre-periphery relationship in the spatial distribution of crime locations. Still, the model underestimates the number of positive sectors, omitting some attractors. Then, the impact of attractive location (i.e. presenting the favourable factors for crime concentration)is evaluated for the series of sexual offences. In fine, the two spatial hypotheses do not seem affected by the attractors identified by the modelling except when the contact sites are clustered in attractive areas. In addition, the share of serial offenders committing their offences in the most attractive locations is smaller than that of single offenders. This observation strengthens the need for working on spatial distribution models instead of calibrated functions with solved cases. [less ▲]

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See detailL’exemple historique dans la pensée de Machiavel et de Guichardin
Moreno, Paola ULg

Scientific conference (2014, October 23)

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See detailTraining alters the innate immune response in the lower airway of horses
Frellstedt, Linda ULg

Doctoral thesis (2014)

Many human and animal studies have examined various markers of the innate and/or adaptive immunity in association with exercise and have come to the general conclusion that exercise, either acute or ... [more ▼]

Many human and animal studies have examined various markers of the innate and/or adaptive immunity in association with exercise and have come to the general conclusion that exercise, either acute or chronic, modifies the immune response. Regular moderate exercise has beneficial and protective effects on immunity because it results in a balance of pro- and anti-inflammatory effects. This balance may be disturbed during exhaustive exercise, such as that experienced during competition and overtraining, resulting in immunosuppression. Humans frequently suffer from upper respiratory tract infections after prolonged intense exercise, whereas horses suffer primarily from lower airway inflammation and/or infection. The underlying mechanism for this difference remains unknown at this time. The sampling of different cell types is limited in humans and therefore, these studies focus on the evaluation of cells in peripheral blood or markers in saliva. Two groups of researchers in human sports medicine have compared populations of sedentary and regularly exercising people. The expression of Toll-like receptors (TLRs) 1, 2, 3 and 4 was decreased in peripheral blood monocytes in exercising subjects. This altered expression of TLRs was also associated with a lower production of pro-inflammatory cytokines (IL-6, IL-1α, TNF-α). Regular exercise induced circulating anti-inflammatory cytokines (IL-10, IL-6) and, therefore, limited the effects of pro-inflammatory cytokines. The first line of defense in the airways is provided by pulmonary alveolar macrophages and bronchial epithelial cells. Strenuous exercise impairs the viability of bronchial epithelial cells, reduces the viral defense mechanisms, and decreases oxidative burst activity of pulmonary alveolar macrophages. The altered immune response in association with exercise/training does not only lead to an increased risk for infection but may also cause the development of allergies and chronic inflammation in the lower airway. This may explain why young equine athletes frequently suffer from Inflammatory Airway Disease (IAD). The etiology of IAD remains unknown but an association with subclinical viral infections as well as inflammatory stimuli from the environment has been suspected. The objective of this work was to increase our knowledge of immune mechanisms in young equine athletes by evaluating the effect of acute exercise and training on the innate immune responses of pulmonary alveolar macrophages (PAM), bronchial epithelial cells (BEC) and monocytes. The hypothesis was that exercise and training modify the TLR mRNA expression as well as the production of pro-inflammatory cytokines and interferons in these three cell types. Eight Standardbred horses were studied over a period of 9 months during which they were acclimatized, trained and deconditioned. Standardized exercise tests were performed regularly and biological samples (blood, bronchoalveolar lavages, and biopsies of the bronchial epithelium) were taken at defined intervals in order to allow a longitudinal evaluation of the different parameters. Monocytes, PAM and BEC were harvested and analyzed. The expression of TLR3 was decreased in equine PAM and monocytes after a period of training, but not after a single strenuous exercise session. In addition, the expression of TLR4 was increased in equine monocytes after training. The production of TNF-α and IFN-β was also examined in PAM and monocytes ex vivo after the stimulation with different TLR ligands. The production of these cytokines was reduced in PAM after a defined period of training and remained decreased for three months thereafter. In contrast, the synthesis of TNF-α was increased after a period of training in equine monocytes and remained increased thereafter. In a second study, a model for the culture of equine bronchial epithelial cells (EBEC) was developed which allowed us to evaluate the effect of exercise and training on the innate immune response of these cells. Acute exercise or training did not alter the TLR mRNA expression in EBEC. The production of IFN-β was increased in EBEC from trained horses after stimulation with a TLR3 ligand. Concurrently, the secretion of TNF-α and IL-6 was impaired in EBEC from trained horses after the stimulation with TLR2 and TLR3 ligands. This study focused on a single aspect of the innate immunity in horses, gaining knowledge of the TLR expression in three cell types and their response to specific TLR agonists. These results have to be considered in the global context of the innate immunity remembering that they represent only a small part of the complex immune system. Only one type of training (Standardbred race training) and one model of acute exercise (standardized exercise test on a treadmill) were evaluated in this study. This should be considered when drawing conclusions, because it is currently understood that the effects on immune responses vary with different types, intensity and duration of exercise and/or training. Nonetheless, this work has established that a local immunosuppression develops within the lungs in trained horses, and may explain the increased susceptibility of exercising horses to pulmonary viral infections. This local immunosuppression is associated with an increased potential of monocytes to produce pro-inflammatory cytokines when challenged with pathogens. The effects of exercise on innate immunity are complex and further studies are needed to continue the work in this field. In addition to the response to training in young sport horses, a number of environmental factors associated with their nutrition and housing may play important roles in the development of pulmonary infections and inflammation (e.g. IAD). To confirm the significance of the presented results, it would be interesting to investigate the innate immune response in trained horses when challenged with equine pathogens, such as equine influenza and equine herpesviruses. The ultimate goal of this work and other studies in the future is to develop immuno-modulating molecules that could be used for the prevention and treatment of equine respiratory diseases. [less ▲]

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See detailManaging understory light to maintain the coexistence of forest tree species with different shade tolerances
Ligot, Gauthier ULg

Doctoral thesis (2014)

Similar to the management of the other environmental resources, forest management has been questioned and more sustainable practices of forest management are being sought. New close-to-nature practices ... [more ▼]

Similar to the management of the other environmental resources, forest management has been questioned and more sustainable practices of forest management are being sought. New close-to-nature practices aim to favor natural processes over human interventions. Particularly, continuous-cover forestry has the goal of relying on natural regeneration, and maintaining irregular stand structure and tree species mixture. However, maintaining mixture of species with different shade tolerances appears arduous with such a silvicultural system. Successfully managing irregular and mixed forests, relying on natural processes, requires a strong knowledge of the ecology of natural regeneration. In particular, strong knowledge is required to predict the result of the interspecific competition in the understory depending upon light availability. The amount of radiation transmitted to the understory is indeed a critical factor determining regeneration dynamics. It determines, at least in part, regeneration composition because of interspecific differences of growth and survival under shade. Moreover, our quantitative understanding of understory light in uneven-aged and mixed stands remains incomplete. A better quantitative understanding of understory light is needed to provide quantitative guidelines for the management of understory light in uneven-aged and mixed stands and, hence, for the management of natural regeneration. The purpose of this thesis is to determine how close-to-nature forest management can maintain mixtures of species with contrasting shade tolerances. I consider ecological conditions with good water and nutrient supplies. In these conditions, partially closed canopy limits the amount of light that reaches the understory, and light is the major factor driving regeneration composition. Consequently, I study the dynamics of natural regeneration with regards to light availability as well as the interception of light by the canopy of heterogeneous stands. Studying the regeneration ecology of two species with contrasting shade tolerances (Fagus sylvatica L. and Quercus petraea (Matt.) Liebl.), I find that the shade-tolerant species outgrow the less shade-tolerant species in all light conditions. Even though the control of understory light with continuous-cover silviculture is required to sustain the growth of less shade-tolerant regenerations, it might not be sufficient to maintain the coexistence of species with contrasting shade tolerances. In order to examine the effects of canopy structure and composition on understory light availability, I use a model of light interception by heterogeneous canopies after synthesizing and discussing the approaches reported in the literature. The model predicts satisfactorily measures of transmitted light even though it is a relatively simple radiative transfer model. I next explore how various silvicultural treatments can be manipulated to provide favorable understory light conditions for natural regeneration. These silvicultural strategies correspond to selective thinnings of five different types, e.g., harvesting preferentially small trees, large trees, or trees of shade-tolerant species or creating circular gaps. The results underline that creating favorable understory light conditions for natural regeneration can be achieved with various regeneration treatments. However, the adequate reduction of stand density depends upon the chosen silvicultural strategies. In particular, creating gaps of about 500 m2 provides adequate light for small regeneration clumps. Harvesting preferentially small and trees of shade-tolerant species are also appropriate but required higher harvest intensity. Harvesting preferentially large trees slightly increases understory light and promotes more shade-tolerant species than less shade-tolerant species. In order to maintain the coexistence of species with contrasting shade tolerances, forest manager must control understory light and manually suppress the regeneration of the shade-tolerant species. The outcome of this study provides foresters with the necessary tools to evaluate how silvicultural treatments can be manipulated to create or maintain favorable light conditions for the regeneration of species of different shade tolerances. Guidelines are additionally proposed for forest managers wanting to maintain the coexistence of species with contrasting shade tolerances. [less ▲]

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See detailThe Airline Container Loading Problem with Pickup and Delivery
Lurkin, Virginie ULg; Schyns, Michael ULg

Conference (2014, October 19)

The present paper looks into the problem of optimizing the loading of a set of containers and pallets into cargo aircraft serving multiple airports. Due to the pickup and delivery operations occurring at ... [more ▼]

The present paper looks into the problem of optimizing the loading of a set of containers and pallets into cargo aircraft serving multiple airports. Due to the pickup and delivery operations occurring at intermediate airports, this problem is simultaneously a weight and balance problem and a sequencing problem. Our objective is to minimize fuel and handling operations costs. This problem is shown to be NP-hard. We resort to a mixed integer linear program. On the basis of a professional partner's real-world data, TNT Airways, we perform numerical experiments using a standard B&C library. This approach yields better solutions than traditional manual planning, which results in substantial cost savings. [less ▲]

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See detailDe l’homme de laboratoire à l’homme en situation : La rigueur d’une phénoménologie clinique
Englebert, Jérôme ULg

Scientific conference (2014, October 17)

Nous voudrions d’abord revenir sur de fausses évidences attachées aux différences entre pratique clinique et recherche. Nous sommes convaincu que la complexité, la rigueur, l’efficacité, voire une ... [more ▼]

Nous voudrions d’abord revenir sur de fausses évidences attachées aux différences entre pratique clinique et recherche. Nous sommes convaincu que la complexité, la rigueur, l’efficacité, voire une hypothétique véracité ne se situent pas, par nature et par principe, uniquement du côté de la recherche fondamentale au détriment d’une pratique clinique qui serait plus intuitive et moins rigoureuse. Nous proposerons ensuite un modèle de recherche directement inscrit dans le paradigme clinique. La psychopathologie phénoménologique, courant émergeant dans la littérature internationale, se caractérise par deux influences majeures : d’une part l’héritage de la réflexion de la philosophie et, d’autre part, elle trouve ses fondements – ses données pourrions-nous dire – dans l’observation de l’homme en situation, c’est-à-dire dans cette pratique clinique. Nous prendrons pour exemples différentes psychopathologies (schizophrénie, anorexie, psychopathie) qui nous permettront de suggérer que la compréhension du patient, et la rencontre de sa subjectivité et de sa sensation, ne peut se limiter à la recherche fondamentale et faire l’économie d’une phénoménologie clinique. Enfin, nous conclurons sur la nécessité d’un regard réciproque à poser entre les connaissances issues des protocoles de recherche en laboratoire et le savoir émergeant de la pratique clinique et de la rencontre de l’homme en situation. [less ▲]

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See detailRecent advances and improvements in computerized adaptive testing with the R package catR
Barrada, Juan Ramon; Magis, David ULg

Conference (2014, October 08)

The purpose of this talk is to present recent advances and developments of the R package catR. This package allows for random generation of response patterns under computerized adaptive testing (CAT) and ... [more ▼]

The purpose of this talk is to present recent advances and developments of the R package catR. This package allows for random generation of response patterns under computerized adaptive testing (CAT) and holds various options to select the first items, estimate ability, select the next item, stop the test and return final results. Two main improvements were realized. First, several rules for next item selection were added, among others, Kullback- Leibler, progressive and proportional methods. Second, catR was limited to dichotomous IRT models so far. The most recent update allows now for several polytomous IRT models, such as partial and generalized partial credit model, graded and modified graded response models, rating scale model, and nominal response model. All improvements will be shortly presented, both from a theoretical point of view and in terms of practical implementation in catR. If possible, several illustrative examples will be displayed in a short live demonstration of catR. [less ▲]

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See detailMultibody Modelling of Mechanical Transmission Systems in Vehicle Dynamics
Virlez, Geoffrey ULg

Doctoral thesis (2014)

This thesis addresses the dynamic modelling of automotive driveline components by means of the nonlinear finite element method for flexible multibody systems. Starting from a detailed study of an ... [more ▼]

This thesis addresses the dynamic modelling of automotive driveline components by means of the nonlinear finite element method for flexible multibody systems. Starting from a detailed study of an industrial application, the TORSEN differential, several contributions are proposed in the field of contact modelling. The contact between rigid bodies in several geometric configurations is investigated and the influence of the squeeze film of lubricating oil is studied. A contact formulation between flexible bodies modelled as superelements is also developed and applied to the modelling of 3D flexible gear pairs. [less ▲]

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See detailKnowledge transfer from Belgian government to medical doctors
MORTELMANS, Katrien; REMMEN, Roy; BERKEIN, Philip et al

Conference (2014, October 02)

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See detailSimulation and optimization of a CHP biomass plant and district heating network
Sartor, Kevin ULg; Quoilin, Sylvain ULg; Dewallef, Pierre ULg

in Applied Energy (2014), 130

Biomass Combined Heat and Power (CHP) plants connected to district heating (DH) networks are recognized nowadays as a very good opportunity to increase the share of renewable sources into energy systems ... [more ▼]

Biomass Combined Heat and Power (CHP) plants connected to district heating (DH) networks are recognized nowadays as a very good opportunity to increase the share of renewable sources into energy systems. However, as CHP plants are not optimized for electricity production, their operation is profitable only if a sufficient heat demand is available throughout the year. Most of the time, pre-feasibility studies are based on peak power demand and business plans only assume monthly or yearly consumption data. This approach usually turns out to overestimate the number of operating hours or oversize the plant capacity. This contribution presents a methodology intended to be simple and effective that provides accurate estimations of economical, environmental and energetic performances of CHP plants connected to district heating networks. A quasi-steady state simulation model of a CHP plant combined with a simulation model of the district heating network installed on the Campus of the University in Liège (Belgium) is used as an application framework to demonstrate the effectiveness of the selected approach. Based on the developed model and actual consumption data, several scenarios for energy savings are considered and ranked. The potential energy savings and resulting energy costs are estimated enabling more general conclusions to be drawn on the opportunity of using district heating networks in urban districts for Western Europe countries. [less ▲]

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See detailÉTUDE DU COMPLEXE ENZYMATIQUE DES SYMBIONTES DU TERMITE RETICULITERMES FLAVIPES (EX. SANTONENSIS)
Tarayre, Cédric ULg

Doctoral thesis (2014)

In the light of the economic, environmental and social context in which we live today, it has become obvious that the use of fossil fuels is not conceivable over the long term. Some alternatives have ... [more ▼]

In the light of the economic, environmental and social context in which we live today, it has become obvious that the use of fossil fuels is not conceivable over the long term. Some alternatives have therefore emerged in recent years. Second-generation biofuels are one of those alternatives and are based on the exploitation of vegetal biomass, also called lignocellulosic biomass. These materials require a hydrolysis step which can notably be achieved by enzymes. Some insects, such as termites, harbor complex microbial communities inside their digestive tracts. Those communities are able to produce enzymes which can be used in the field of the hydrolysis of vegetal biomass. This is what this thesis deals with. The main part of the work done focused on the research of enzyme-producing microorganisms (bacteria, mycetes and protists) responsible for the degradation of hemicelluloses and cellulose, the hydrolysis of which releases fermentable sugars. The insect which was used in this work was Reticulitermes flavipes (ex. santonensis), a lower termite, harboring a highly diversified internal microflora. This thesis describes the characterization of the microbial strains which were isolated and the enzymes they secrete. A complementary part of this research focussed on termites grown on artificial diets. The objective of this part was multiple : isolating enzyme-producing strains, not extractable according to the standard technique, and characterizing the microflora resulting from the applied artificial diets. This multidisciplinary approach was based on microscopy, proteomics, metagenomics and the assessment of metabolism applied to the different microbial consortia. [less ▲]

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See detailMicrocrystalline cellulose, a direct compression binder in a quality by design environment—A review
Thoorens, Grégory; Krier, Fabrice ULg; Leclercq, Bruno et al

in International Journal of Pharmaceutics (2014), 473(1-2), 64-72

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See detailVelocity and turbulence measurements for assessing the stability of riverbeds: a comparison between UVP and ADVP
Duma, Diana ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in 11th International Conference on Hydroscience & Engineering - "Hydro-Engineering for Environmental Challenges" (2014, October)

Maintaining the overall stability of active riverbeds requires a deep understanding of the complex interactions between turbulent flow forces and forces stabilizing the riverbed. Standard approaches do ... [more ▼]

Maintaining the overall stability of active riverbeds requires a deep understanding of the complex interactions between turbulent flow forces and forces stabilizing the riverbed. Standard approaches do not properly take into account the turbulence fluctuations in non-uniform flows, while these are of primary importance in the mechanisms determining the stability of stones. In a new approach, the flow forces are quantified by means of parameters combining explicitly the velocity and turbulence distributions over a certain water depth above the riverbed. In this paper, as an onset for using these newly developed bed stability parameters, we report on new experimental measurements of velocity and turbulent kinetic energy based on acoustic methods, whereas all previous uses at the new bed stability parameters relied on Laser PIV Techniques. For quasi-uniform and non-uniform flow conditions, velocity measurements were conducted with two complementary devices: an ultrasonic velocimeter probe (UVP) and an acoustic Doppler velocimeter profiler (ADVP). The results are compared and discussed in detail. A general consistency between the two types of measurements is obtained, while some discrepancies are highlighted close to the bed and tentative explanations are given. [less ▲]

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