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See detailCharacterization of near-death experiences and their experiencers
Martial, Charlotte ULiege

Doctoral thesis (2018)

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See detailEtude des propriétés physicochimiques des matières grasses d’Irvingia gabonensis et de Dacryodes edulis en vue de leur intégration dans des formulations alimentaires
Yamoneka Wasso, Juste ULiege

Doctoral thesis (2018)

Irvingia gabonensis seed and Dacryodes edulis pulp contain significant proportions of fats, used in central and west Africa in several food formulations. In order to promote their valorization at an ... [more ▼]

Irvingia gabonensis seed and Dacryodes edulis pulp contain significant proportions of fats, used in central and west Africa in several food formulations. In order to promote their valorization at an industrial scale, their physicochemical properties were evaluated. The results showed that I. gabonensis seed fat (IGF) is a lauric fat, solid at room temperature stable in β 'form. This fat could be used in several oil blends as base stock with many applications. D. edulis pulp oil (DPO) is a liquid oil with many potential uses as cooking oil or liquid oil in industrial blends oils. The high solid fat content of IGF at 37°C, and its complete melting around 40°C is the limiting factor for its direct valorization in several food formulations. In order to overcome this constraint, it was blended with DPO and other three liquid oils. The binary blends containing 20%, 30% of IGF and 80%, 70% of rapeseed and groundnut oils showed similar hardness and SFC with fats extracted from commercial margarine. The interesterified blend containing 90% of IGF and 10% of DPO showed a melting behavior similar to that of cocoa butter. This suggested the blend could be used as cocoa butter substitute in confectionary industry. The valorization of these two oils in food industry could promote the organization of their sectors for a better contribution to the local economy [less ▲]

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See detailLocal perceptions on the New agenda for cooperation and border development in the Brazilian-Uruguayan cross-border region
Matiuzzi de Souza, Gustavo ULiege

Doctoral thesis (2018)

This thesis identifies local actors’ perceptions on the operationalization of the New Agenda for Cooperation and Border Development (New Agenda) in the Brazilian- Uruguayan cross-border region (BUCBR ... [more ▼]

This thesis identifies local actors’ perceptions on the operationalization of the New Agenda for Cooperation and Border Development (New Agenda) in the Brazilian- Uruguayan cross-border region (BUCBR), emphasizing the relationship between formal (state) and informal (non-state) actors and processes. After fifteen years, local actors’ engagement in New Agenda’s projects, and compliance with its agreements and frameworks were extremely low. If the New Agenda should be considered a response to local demands, why was/is there such low engagement and compliance of local actors with its projects and agreements? To answer this question, this thesis draws from International Relations theories a plural, reflectivist and constructivist approach that enables the employment of ‘perception’ as a relevant analytical variable. The use of interviews and the application of an electronic survey are the main primary sources. Bibliographical research and official statistics are applied for contextual data. Historical analysis is employed for comprehending the relationship between state and non-state actors in the social construction of the BUCBR. This thesis finds that compliance and engagement have little to do with a border culture of informality and illegality. They are related more to a New Agenda’s deficient institutionality and the perpetuation of ignorance toward the social reality of the BUCBR and the demands of local actors. The issues of engagement and compliance of local actors with the New Agenda is intimately linked with the unsatisfactory state offer of institutionality capable to turn the BUCBR into a legal and normative space in which the region could implement, autonomously, local development strategies for its cross-border populations. Such an institutionality would potentially change the way formal and informal actors relate. Moreover, the deeply rooted trans-local modus agendi of the region is likely to be either cause for resistance of any project that attempts to control or change it or the basis of novel cooperative regimes. [less ▲]

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See detailInfluence of combined environmental constraints on photochemical capacity and CO2 fluxes in a temperate managed grassland.
Digrado, Anthony ULiege

Doctoral thesis (2018)

Increase in agricultural production to insure food security and energy demand by 2050 might result in higher greenhouse gas emissions (GHG) from the agricultural sector. Managed grasslands, however, offer ... [more ▼]

Increase in agricultural production to insure food security and energy demand by 2050 might result in higher greenhouse gas emissions (GHG) from the agricultural sector. Managed grasslands, however, offer the opportunity to offset some of the GHG emission through the storage of carbon in terrestrial systems by photosynthesis. Photosynthesis, however, is highly sensitive to environmental conditions. Especially, plant ability to harvest and use light energy for photochemistry can be impaired by abiotic stresses. While numerous studies have focused on the impact of environmental constraints on ecosystem carbon fluxes, the influence on ecosystem photochemical capacity is understudied. The main goals of this thesis was to evaluate how environmental constraints impacted the grassland photochemical capacity and how variations in processes involved in light reactions of photosynthesis influenced ecosystem carbon fluxes. Frequent chlorophyll fluorescence measurements were conducted over a two-year period, on three grassland species (Lolium perenne L., Taraxacum sp., and Trifolium repens L.). The ecosystem photochemical capacity was estimated from measurements performed on the three grassland species. In addition, monitoring CO2 fluxes was performed by eddy covariance. Our results showed that photochemical capacity of the primary grasslands species exhibited diurnal and seasonal variations. The monocot L. perenne and the dicots (Taraxacum and T. repens) exhibited different acclimation strategies. All species exhibited the onset of energy dissipation mechanisms within the photosystem II but expressed contrasted response in the photosystem I efficiency. As a result, the ecosystem also exhibited variations in its ability to harvest and use photon energy. The strongest declines in photochemical capacity were observed in summer when abiotic stresses such as high light and high air temperature were combined. However, decrease in photochemical capacity did not result in a decreased ability to fix carbon in the grassland. The maintenance of carbon assimilation despite the onset of energy dissipation mechanisms can be explained by the higher availability of light energy under these conditions. In the final section of this PhD thesis, we discuss how future experiments can improve our knowledge in plants functional ecology and in the relationship between the photochemical capacity and ecosystem carbon fluxes. We also discuss how these results can benefit GHG mitigation strategies and how plants influence GHG balance through other routes than photosynthesis. [less ▲]

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See detailL'architecture religieuse dans l'ancien diocèse de Liège de 1450 à 1600. Bâtir et conserver le bâti à la fin du Moyen Âge et au début des Temps modernes
Joly, Emmanuel ULiege

Doctoral thesis (2018)

Issu de recherches poussées dans les archives, ce travail met en lumière quelques chantiers importants de construction, reconstruction ou restauration menés dans les églises de l’ancien diocèse de Liège – ... [more ▼]

Issu de recherches poussées dans les archives, ce travail met en lumière quelques chantiers importants de construction, reconstruction ou restauration menés dans les églises de l’ancien diocèse de Liège – à l’exclusion des parties relevant du duché de Brabant - aux XVe et XVIe siècles. Ainsi, en étudiant l’histoire de la construction de plus d’une vingtaine d’édifices – la cathédrale Saint-Lambert de Liège ; des collégiales à Liège, Maestricht, Tongres, Huy, Namur, Dinant ; des abbatiales comme Saint-Jacques à Liège, Saint-Hubert ou Stavelot ; des couvents (les Croisiers à Maestricht) ; des paroissiales urbaines (à Saint-Trond, Hasselt, Visé, Bastogne ou Weert) – et en confrontant dans la mesure du possible les données archivistiques au bâti existant, nous avons pu mettre en évidence les liens qui existaient entre ces chantiers. Forte de ces nouvelles données factuelles, cette étude fait le point sur les personnalités actives sur les chantiers de construction – et en particulier les « maîtres d’œuvre » dont Arnold van Mulcken, Paul de Richelle et la famille des Nuremberg –, sur les réseaux d’approvisionnement en matériaux pierreux et enfin sur les formes et motifs de l’architecture de cette période où se côtoient le gothique de la Renaissance et les expressions antiquisantes et italianisantes. [less ▲]

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See detailPREBIOTIC POTENTIAL OF NOVEL NON-DIGESTIBLE CARBOHYDRATES FOR PREVENTION AND CONTROL OF SALMONELLA TYPHIMURIUM IN PIGS
Tran, Thi Hanh Tham ULiege

Doctoral thesis (2018)

Foodborne diseases have drawn increasing attention around the world. Salmonelloses are the second most common zoonosis in humans after campylobacteriosis in the European Union (EU). Pig, after poultry, is ... [more ▼]

Foodborne diseases have drawn increasing attention around the world. Salmonelloses are the second most common zoonosis in humans after campylobacteriosis in the European Union (EU). Pig, after poultry, is the second most important domestic animal species associated the outbreaks of salmonellosis in humans. In addition, pig production is the most important among the principal domestic animal species in the world. A supply of the consummers’ market with Salmonella-free pig meat would be important to animal production, as well as to human food safety. The control of this pathogen in pigsties by prebiotics is an approach that deserves consideration. A wide range of molecules including non-digestible carbohydrates have attracted increasing interest to prevent the harmful effects of pathogens such as Salmonella enterica. The aim of this research thesis is to assess the in vitro and in vivo potential of some novel carbohydrates to reduce Salmonella Typhimurium infections in weaned piglets. Firstly, an in vitro batch fermentation system was improved by including mucus. This study investigated whether the survival of a wider number of intestinal bacterial populations is impacted by the presence of mucus and whether this dependence on mucus is influenced by the fermented ingredient. The introduction of mucins affected many microbial genera and fermentation patterns. Mucins increased final gas production with inulin and shifted short-chain fatty acid molar ratios. Lactobacillus spp. and Bifidobacterium spp. were decreased with mucins. In contrast, Proteobacteria, Verrucomicrobia, Ruminococcaceae, Bacteroidaceae (including Bacteroides spp.), and Akkermansia spp. were increased. In addition, Proteobacteria and Lachnospiraceae were promoted in the mucus compared with the broth, while Ruminococcaceae decreased. However, this impact of mucus on microbial genera and fermentation patterns was independent of the fermentation substrate. The improved in vitro fermentation model of the pig intestines was used to assess prebiotic potential of novel non-digestible carbohydrates (NDCs) and their influence on Salmonella Typhimurium. Inulin, cellobiose, pectic- (POS), isomalto- (IMO), xylo-(XOS) oligosaccharides, and gluconic acid (GLU) were fermented for 72 h. None of the tested NDCs did inhibit Salmonella Typhimurium counts compared to control. However, inulin and IMO displayed prebiotical properties, since they supported the highest Lactobacillus and Bifidobacterium populations after 12 and 24 h of fermentation. Cellobiose and GLU also promoted Lactobacillus populations, but not Bifidobacteria. Looking at the fermentation patterns, GLU was weakly fermented but was the fastest fermenting NDC with the highest butyrate molar ratio. POS was slowly fermented, while XOS was poorly fermented. Cellobiose yielded the highest lactate molar ratio. Finally, based on the results from the second in vitro trial and data obtained on mice, two promising prebiotics, IMO and POS were chosen to evaluate their prebiotical properties in an in vivo Salmonella Typhimurium challenge using a Trojan piglet model. IMO could be potential a prebiotic to improve performance, strengthen serum immune system, and decrease the Salmonella prevalence in piglets. POS did not present these properties. It is concluded that although all tested NDCs did not reduce Salmonella Typhimurium growth, IMO seems the most promising prebiotic in terms of fermentation patterns, host responses, transmission and colonization of Salmonella in piglets. Cellobiose and GLU were only tested in in vitro system, but owing to their specific fermentation patterns, they deserve some attention and could also be assessed in vivo to confirm their action on pathogens. [less ▲]

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See detailHeterogeneous photocatalysis for water and air depollution
Mahy, Julien ULiege

Doctoral thesis (2018)

In this work, a TiO2 aqueous sol-gel process was developed to produce, at large scale, photocatalysts with hydrophilic property and high activity, both under visible and UV/visible light, for water and ... [more ▼]

In this work, a TiO2 aqueous sol-gel process was developed to produce, at large scale, photocatalysts with hydrophilic property and high activity, both under visible and UV/visible light, for water and air remediation. The first step was to develop an easy aqueous sol-gel synthesis of pure TiO2 at laboratory scale. The synthesis protocol was simplified to reduce the synthesis time, the temperature and the number of steps as washing step. The physico-chemical and photocatalytic properties of the obtained materials have been characterized to assess the production of hydrophilic coatings on stainless steel and the formation of efficient photocatalysts for the degradation of three pollutants (methylene blue, p-nitrophenol or acetaldehyde) under different shapes (film or powder) and in different phases (liquid or gaseous). Then this synthesis has been up-scaled to a volume of 5 L and deposited with a pilot line on stainless steel. The produced coating was characterized and compared to the laboratory material to show the successful operation of up-scaling. In second part, the aqueous synthesis was adapted to produce TiO2 catalysts doped with Fe3+, Ag+, Cu2+, Zn2+, Cr3+, Al3+, Mn2+, and Co2+ ions and Pt metallic nanoparticles in order to improve their activity. Some dopants showed an increased photoactivity and some mechanisms were proposed to explain these modifications of activity with doping. Furthermore, cost comparison at laboratory scale showed that Zn2+ doping may be considered for industrial applications. Using this method, a large scale Zn-doped TiO2 photocatalyst was synthesized with properties homologous to the lab-scale product. The third step was to study the redispersion property of the nanocrystalline TiO2 colloids. Indeed, the powders obtained by air drying of these colloids can be redispersed in water to produce colloids which are compared to the initial one. Five cycles of drying-redispersion were achieved on selected colloids. A mechanism was proposed to explain this interesting property, acid present in the synthesis seems to be the main factor. This would be very useful for an industrial application of this synthesis allowing to reduce the volume and weight for transportation and storage. In the last part of this work, the aqueous TiO2 photocatalyst was modified to extend his activity towards visible light. In this aim, silylated porphyrin and nitrogen-based reagents were used. The silylated porphyrin was synthesized in laboratory and co-hydrolysed with a titanium precursor in aqueous medium to produce hybrid TiO2 photocatalyst. Results showed that the porphyrin fragments are held to the resulting matrix through strong Si-O-Ti covalent bonds limiting leaching of the former and an increased photoactivity under visible was obtained. Concerning nitrogen doping, three N-precursors were used: urea, ethylenediamine and triethylamine. Results showed the incorporation of nitrogen in TiO2 materials allowing absorption in visible region and improvement in visible activity on the remediation of polluted water with p-nitrophenol. The best doping, regarding cost, activity and ease of synthesis, was successfully up-scaled to volume of 5 L and compared to commercial Degussa P25 material. [less ▲]

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See detailConception of a near-infrared spectrograph for the observation of massive stars
Kintziger, Christian ULiege

Doctoral thesis (2018)

This research contribution intends to introduce the conception of a new fiber-fed spectrograph, called NƎSIE, that operates in the near-infrared domain. This PhD thesis was part of a research project led ... [more ▼]

This research contribution intends to introduce the conception of a new fiber-fed spectrograph, called NƎSIE, that operates in the near-infrared domain. This PhD thesis was part of a research project led by Prof. Rauw which focuses on massive stars. The final location of NƎSIE will be the TIGRE telescope located in La Luz, Mexico. The observational data provided by this instrument will help several research groups from the University of Liège to study massive stars. In particularly, evolution models will be improved through the comparison of the collected spectra with theoretical models. This collaboration will therefore contribute to a better understanding of massive stars and the mechanisms that take place within these extraordinary objects. [less ▲]

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See detailEnregistrement sédimentologique et minéralogique des changements environnementaux du littoral Nord de Sfax (Tunisie) au cours de l'Holocène
Lamourou, Ali ULiege

Doctoral thesis (2018)

L’étude sédimentologique et minéralogique des dépôts holocènes du littoral Nord de Sfax (Tunisie) a permis l’identification de sédiments d’environnements sédimentaires très distincts. L’analyse de ... [more ▼]

L’étude sédimentologique et minéralogique des dépôts holocènes du littoral Nord de Sfax (Tunisie) a permis l’identification de sédiments d’environnements sédimentaires très distincts. L’analyse de l’enchaînement vertical des faciès de dépôt a permis d’identifier à la base des carottes un environnement de sédimentation fluviatile (plaine côtière) marquée essentiellement par des faciès de chenaux fluviatiles et de plaine d’inondation et au sommet un environnement de sédimentation marine littorale caractérisé par des sables riches en gastéropodes, lamellibranches et algues. Cette évolution des facies traduit une élévation relativement rapide du niveau marin qui aurait submergé le système fluviatile au niveau de la plaine côtière. Cette élévation eustatique serait liée à la transgression holocène d’âge 6500 ans BP. Les corrélations chronostratigraphiques des faciès ont permis de reconstituer l’architecture des dépôts et l’évolution de la paléogéographie du Sud-Est de la Tunisie avant, au cours et en fin de l'intervalle de temps holocène. Le modèle sédimentologique, établi pour l’Holocène du Sud-Est de la Tunisie, correspond à une sédimentation de type plate-forme interne comprenant un système lagunaire à l’Ouest à dépôt de faible énergie, relayés vers l’Est par des faciès plus ouverts aux influences marines représentés par des faciès bioclastiques énergétiques. La reconstitution de l’agencement des environnements des dépôts du littoral Nord de Sfax, et des faciès qui leur sont associés, présente une forte similitude avec le paysage du Sud-Est de la Tunisie au cours de l’Holocène. En effet, les îles barrières qui isolent vers l’arrière un système lagunaire, correspondent en majeure partie à des deltas de marée essentiellement oolithiques. Ce constat permet de transposer cette configuration actuelle au Sud-Est de la Tunisie à l’Holocène. L’étude morphologique des foraminifères benthiques récoltés dans les sédiments superficiels de l’unité marine tend à montrer l'existence d'une pollution du littoral actuel. Cette pollution est enregistrée dans les tests des foraminifères benthiques essentiellement sous forme de déformations de la coquille, des loges ou des stries ou encore par des couleurs anormales. Les résultats obtenus au cours de cette thèse ont permis de reconstituer l’agencement des environnements des dépôts du littoral Nord de Sfax au cours de l'Holocène, une comparaison avec les archives historiques de Sud-Est Tunisien est nécessaire pour confirmer les interprétations proposées dans cette thèse. [less ▲]

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See detailIntroduction à l’evidence-based practice dans la formation initiale en logopédie et en médecine : évaluation de dispositifs mis en place à l’Université de Liège
Durieux, Nancy ULiege

Doctoral thesis (2018)

Le présent travail de thèse a pour objectif principal d’évaluer – afin de proposer des pistes d’amélioration – les dispositifs de formation à l’approche evidence-based practice (EBP) développés pour les ... [more ▼]

Le présent travail de thèse a pour objectif principal d’évaluer – afin de proposer des pistes d’amélioration – les dispositifs de formation à l’approche evidence-based practice (EBP) développés pour les étudiants en logopédie et en médecine à l’Université de Liège et de contribuer ainsi à l’évolution de l’enseignement de l’EBP dans ces disciplines. [less ▲]

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See detailSingle-cell approaches for the characterization of microbial population dynamics in bioprocesses
Baert, Jonathan ULiege

Doctoral thesis (2018)

Some evidences show that a clonal population of microbial cells exhibits variation at their physiological level. For this reason, several methods that allow cellular characterization with a single-cell ... [more ▼]

Some evidences show that a clonal population of microbial cells exhibits variation at their physiological level. For this reason, several methods that allow cellular characterization with a single-cell resolution have been strongly developed this last decade. For instance, flow cytometry is a reliable analytic method to study the complex distribution of physiologies occurring among microbial populations. This so called “phenotypic heterogeneity” has been extensively discussed in the scientific literature and remains a hot topic for biotechnology development suggesting that clonal cells have not the same ability to synthesize a product of interest during bioprocesses course. However, phenotypic heterogeneity patterns are not commonly interpreted in term of biological performances. Therefore, the current main challenges in single-cell techniques lies in an accurate understanding of the sources of biological inefficiency through a relevant interpretation of the phenotypic heterogeneity occurring in microbial populations. For this purpose, this work investigates the potentialities of both genetically encoded and exogenous biosensors to support the implementations of innovative optimization strategies considering biological traits of cell factories. Moreover, correlation between cell population heterogeneity and bioreactor heterogeneity has also been addressed by studying the response of biosensors under intensive culture conditions that occurs in industrial bioreactors. Thus, thanks to a deep analysis of biosensor signals, this work point out the added value brought by the single-cell concepts and make possible a better understanding of microbial physiology in bioprocesses conditions. Additionally, in parallel with an extended experimental strategy, this work proposed an original formalism in order to valorize the different component of single-cell technology and to facilitate its transfer towards industrial applications. Finally, beside challenges in link with biosensors signals interpretation, flow cytometry analysis leads to the high-throughput characterization of cell suspension and then, provides thousands of data. This high information diversity compels to cope with strong data management challenges. Actually, the question is: “How structure and treat single-cell data to improve their interpretations accuracy? In this frame, this study demonstrates the potential of single-cell distribution statistical treatment to rationally discriminate cellular samples which present different biological traits. In that way, we shown experimentally that the higher performant biological system can also be the more heterogeneous which is in opposite to the paradigm stating that only homogenous population are attractive for bioprocess applications. In a nutshell, this work set up the basis to study the relation between phenotypic heterogeneity and biological performance through the discussion of serval fundamental and applied concepts. That supports the proposal of rational optimization strategies while considering biological inputs and ensuring the valorization of single-cell concept as a response to current major industrial challenges. [less ▲]

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See detailCorrection of Electromagnetic Measurements and Active Shaping of Electromagnetic Fields in Complex and Reverberating Environments
Spirlet, Maxime ULiege

Doctoral thesis (2018)

With the growing number of wireless devices and connected objects, the level of electromagnetic noise could reach unprecedented levels, potentially leading to malfunctions. In order to limit this effect ... [more ▼]

With the growing number of wireless devices and connected objects, the level of electromagnetic noise could reach unprecedented levels, potentially leading to malfunctions. In order to limit this effect, it is important on the one hand to develop systems with enhanced immunity to radiated electromagnetic fields and, on the other hand, to further rationalize the electromagnetic radiation of wireless devices by improving their design. In this dissertation, two axes of research are addressed. The first aims to help prototyping antennas by accelerating and simplifying the measurement of antenna radiation patterns by performing this measurement in non-dedicated environments, i.e. outside fully anechoic chambers. To achieve this, a method of correction is applied to measured electromagnetic fields a posteriori to remove from the radiation pattern the spurious contributions introduced by reflections occurring in the reverberating test environment. The method described in the first part of the manuscript is based on the angular deconvolution of the impulse response of the environment from the echoic pattern. At the end, the results of experimental validations, obtained through several test cases, are presented. The second axis focuses on the electromagnetic field shaping in reverberating and complex environments, as it would be particularly useful for radiated immunity electromagnetic compatibility tests, allowing them to be performed in arbitrarily reverberating environments without requiring the systematic use of anechoic chambers. Field shaping techniques aim on the one hand to suppress any electromagnetic field introduced by one or more sources of undesired noise in a determined part of an arbitrary environment, and on the other hand to superimpose any arbitrary electromagnetic field map such as plane waves used for radiated immunity tests. To achieve this, a method of field shaping, based on the optimal control theory of Maxwell's equations, is presented. The potential of this method can be appreciated thanks to several numerical simulations presented for various environments. Then, by means of two experimental test cases of more modest complexity, the experimental validité of the method is established. [less ▲]

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See detailSpatiotemporal modeling of interactions between urbanization and flood risk: a multi-level approach
Mustafa, Ahmed Mohamed El Saeid ULiege

Doctoral thesis (2018)

Flooding in urban areas is an increasing problem and it causes over one-third of overall economic losses due to natural hazards across the globe. For many river basins, studies show that flood risk will ... [more ▼]

Flooding in urban areas is an increasing problem and it causes over one-third of overall economic losses due to natural hazards across the globe. For many river basins, studies show that flood risk will further increase during the 21st century as a result of a combination of climate change and urban development. It is important in this respect to evaluating flood risks at different time horizons by coupling urban development models with hydrological models. Although often focused on flood hazard only, the existing studies suggest (i) an overwhelming contribution of urbanization to the future increase in flood risk in some river basins, and (ii) a likely high influence of small-scale spatial patterns in future urbanization, requiring analyses at a finer scale than performed so far. The main goal of this PhD thesis is to investigate the expected flood damage for possible future built-up patterns at different scales. Wallonia (Belgium) is selected as a case study for this thesis. Four main steps are followed to accomplish the thesis’ goal. First, this thesis takes a retrospective analysis of the evolution of the urban development in Wallonia through the use of a multinomial logistic regression model (MNL). Second, in order to estimate the future flood damage for urban areas, there is a need for urbanization scenarios that are based on a realistic land-use change model. In this context, this research proposes and compares two land-use change models: (i) a coupled MNL and cellular automata model (MNL-CA), and (ii) a coupled CA and agent-based model (CA-AB). Based on the comparison of both modeling approaches, the CA-AB model is employed to simulate several future urbanization scenarios. These scenarios are typically considering long-term time horizons, i.e. 2050-2100, as this is the appropriate time frame for analyzing such effects. In this thesis, Belgian cadastral datasets for 1990, 2000 and 2010 are used to calibrate and validate the land-use change models. A remarkable feature of this research is that it considers multiple densities of built-up which enables us to study both expansion and densification processes. As the model simulates urbanization up to 2100, forecasting land-use change over such time frames entails very significant uncertainties. In this regard, one of the main themes of this thesis is attributed to the modeling of uncertainty in the land-use change models. Third, 24 urbanization scenarios for the entire Wallonia for 2030, 2050, 2070 and 2100 that differed in terms of the rate of development and spatial policies are generated. The simulated scenarios will then be integrated with a hydrological model for the same time horizon. The inundation extents and water depths for each scenario are determined by a hydraulic model for steady flows corresponding to return periods of 25, 50 and 100 years. The results suggest that urban development will continue within flood hazard zones in many of the simulated scenarios. Therefore, fourth, a procedural urban generation system is developed to analyze the respective influence of various urban layout characteristics on inundation flow which assists in designing flood-resistant urban layouts within the flood hazard zones. The results pointed out that the assumption of a binary approach of urbanization modeling, urban vs non-urban, may lead to inaccurate conclusions as the relative importance of the development controlling factors typically varies with density. Our results show that the densification strategy, without spatial policy interventions, may lead to an increase in the flood absolute damage by a 100% at the end of the century. Another important finding of this thesis is that the geometric factors of urban layouts, such as road width, orientation or curvature, have a role in water flow properties during floods. Thus, the thesis provides some guidelines for designing flood-sensitive urban layouts. [less ▲]

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See detailBioefficacité d'Ocimum spp. (Lamiaceae) pour une gestion intégrée des ravageurs en cultures maraîchères.
Yarou, Boni ULiege

Doctoral thesis (2018)

Les pesticides de synthèse utilisés pour lutter contre les ravageurs des cultures maraîchères en Afrique de l’Ouest demeurent un problème compte tenu de leur nocivité sur l’homme et l’environnement, en ... [more ▼]

Les pesticides de synthèse utilisés pour lutter contre les ravageurs des cultures maraîchères en Afrique de l’Ouest demeurent un problème compte tenu de leur nocivité sur l’homme et l’environnement, en plus de la sélection de populations résistantes chez ces ravageurs. Cependant, la flore ouest-africaine regorge de nombreuses plantes aux potentiels biocides qui pourraient constituer une alternative à l’utilisation de ces pesticides de synthèse. Cette thèse s’inscrit dans une politique de valorisation de légumes traditionnels du genre Ocimum dans la gestion des ravageurs des cultures maraîchères. Ainsi, l’effet des espèces Ocimum gratissimum L. et O. basilicum L. (Lamiaceae) sur le comportement de pucerons et de Lépidoptères a été évalué à partir des huiles essentielles – utilisées sous forme de diffuseurs – et des plantes entières utilisées comme plantes associées. Dans un premier temps, un inventaire de l’entomofaune associée au basilic tropical (O. gratissimum) réalisé dans les conditions du Sud-Bénin a permis de mettre en évidence la présence de 52 familles d’insectes. Les plus abondantes par ordre décroissant du nombre d’individus par famille sont les Formicidae, les Coccinellidae, les Acrididae, les Lygaeidae, les Pentatomidae, les Chrysomelidae, les Megachilidae et les Halictidae. Au sein de ces familles, figurent aussi bien des ennemis naturels (Coccinellidae, Syrphidae, Braconidae) que des pollinisateurs (Megachilidae, Halictidae) et des ravageurs (Pentatomidae, Acrididae). Ensuite, l’effet biocide d’O. gratissimum et O. basilicum a été étudiée. Au laboratoire, les huiles essentielles et les plants d’Ocimum disposés à proximité des plants de tomate (Solanum lycopersicum L.) réduisent significativement l’activité de ponte de Tuta absoluta Meyrick. Aussi, les huiles essentielles peuvent réduire le potentiel reproducteur des pucerons, tandis que dans un système d’association culturale, les plants d’Ocimum induisent une activité répulsive sur les pucerons et peuvent aussi impacter la reproduction de ces pucerons. Au champ, seul l’effet du basilic tropical a été testé sur les trois principaux ravageurs du chou (Brassica oleracea L.) – Hellula undalis Fabricius, Plutella xylostella L., Spodoptera littoralis Boisduval. Cette association basilic tropical-chou permet non seulement de réduire l’abondance de ces ravageurs, mais aussi l’importance des dégâts sur les parcelles associées. Le potentiel biocide de ces légumes traditionnels sur les ravageurs des cultures maraîchères et l’importance de l’entomofaune utile associée à ces plantes, peuvent dès lors présenter un moyen de gestion intégrée des ravageurs en cultures maraîchères afin d’améliorer la qualité sanitaire des produits et la santé des populations. [less ▲]

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See detailMultiscale study of hydrodynamics, mixing and gas-liquid mass transfer in a stirred-tank bioreactor
de Lamotte, Anne ULiege

Doctoral thesis (2018)

The growth of industrial biotechnology has created a pull for advancing bioreactor design. The requirements of the culture system have led to a variety of technical issues that generally involve transfer ... [more ▼]

The growth of industrial biotechnology has created a pull for advancing bioreactor design. The requirements of the culture system have led to a variety of technical issues that generally involve transfer of mass and energy. Predicting bioreactor performance has proved to be complex as it requires not only a deep knowledge of all the biological aspects, but also a proper characterization of transport and transfer phenomena within the bioreactor which are equipment design and scale dependent. In stirred-tank bioreactors, hydrodynamics governs bulk fluid mixing and gas-liquid mass transfer. The understanding and quantification of these three physical key aspects and of their interactions are required within the framework of scale-up or scale-down. Due to their simplicity, traditional scaling criteria based on global quantities are obviously not able to account for the intricacy of the local hydrodynamics, mixing and mass transfer properties. This dissertation is part of a project aiming at a better mastering of phenomena linked to gas-liquid transfer that govern the performance of biochemical processes. It studies the influence of mixing and circulation imposed by hydrodynamics, within a baffled stirred-tank reactor, on the gas-liquid transfer through the liquid free surface and on the spatiotemporal distribution of the dissolved gas concentration. The major thrust of this work is to improve the description of fluid dynamics, mixing and gas-liquid mass transfer in stirred-tank bioreactors. The main input is the development and validation of a characterization experimental and computational approach that allows understanding, quantifying and modeling these multiscale transport and transfer phenomena during bioreactor implementation, in particular the selection of agitation configuration and operating conditions. [less ▲]

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See detailMultiple outputs operational modal identification of time-varying systems
Bertha, Mathieu ULiege

Doctoral thesis (2018)

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See detailProbing the broad emission line region of quasars using gravitational microlensing
Braibant, Lorraine ULiege

Doctoral thesis (2018)

This thesis exploits microlensing of the BLR to constrain its geometry and kinematics. BLR microlensing is investigated through two complementary methods: (i) a model-independent decomposition of the ... [more ▼]

This thesis exploits microlensing of the BLR to constrain its geometry and kinematics. BLR microlensing is investigated through two complementary methods: (i) a model-independent decomposition of the microlensed part of the quasar spectrum, and (ii) comparison of observations to simulated line profile distortions. Those two approaches are applied to high-quality spectra of the lensed quasars HE0435-1223 and QSO2237+0305. Both quadruply-imaged quasars show significant line profile distortions that can be robustly attributed to microlensing. This investigation especially focuses on the image D of quasar HE0435-1223 and on the image A of QSO2237+0305, which are affected by the largest microlensing effects. [less ▲]

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See detailEtude du potentiel des enzymes de Cynara cardunculus L. en technologie fromagère
Ben Amira, Amal ULiege

Doctoral thesis (2018)

L’objectif des travaux entrepris au cours de cette thèse visait à identifier, extraire et caractériser les enzymes coagulants des fleurs de Cynara cardunculus L., en vue de les valoriser dans la ... [more ▼]

L’objectif des travaux entrepris au cours de cette thèse visait à identifier, extraire et caractériser les enzymes coagulants des fleurs de Cynara cardunculus L., en vue de les valoriser dans la technologie des produits laitiers. Dans une première étape, deux lots de fleurs, collectés à deux stades de maturation, ont été comparés d’un point de vue biochimique et enzymatique, afin de sélectionner le lot approprié pour une meilleure production d’enzymes coagulants. Les fleurs collectées au milieu du stade de maturation (fin du mois de juin) ont alors été sélectionnées pour la suite des travaux. Les critères de sélection étaient basés sur la composition chimique des fleurs, les activités enzymatiques des extraits coagulants, ainsi que sur les propriétés texturales des caillés produits. Dans une deuxième étape, le contenu enzymatique des fleurs a été identifié par une approche protéomique. L’étude a révélé la présence de 4 cardosines (A, E, G et H), dont la cardosine A qui a une spécificité d’action similaire à celle de la chymosine. L’absence des autres cardosines (B, C, D et F) constitue un avantage pour la réduction de l’activité protéolytique excessive, responsable de l’amertume et des défauts de texture des fromages. La partie suivante de la thèse a concerné l’étude de l’extraction de la présure de C. cardunculus et son application dans le processus de coagulation du lait. Cette étude était divisée en deux parties complémentaires. Dans un premier temps, nous nous sommes intéressés à évaluer l’effet du pH d’extraction sur les propriétés techno-fonctionnelles des extraits bruts des fleurs. Dans un deuxième temps, les conditions d’extraction de la présure ont été optimisées par méthodologie des surfaces de réponses, en vue de maximiser son activité coagulante. Les conditions optimales étaient alors sélectionnées. L’efficacité de l’extrait coagulant a été testée dans la coagulation de deux types de laits bovins (cru et reconstitué), en appliquant deux doses d’extrait coagulant (0,5 mg et 1 mg/10 mL de lait). Les résultats ont montré des propriétés viscoélastiques et des fermetés des gels élevées, similaires à ceux d’une chymosine commerciale. Pour terminer, l’étude des propriétés technologiques des gels était accompagnée d’une évaluation de la qualité des fromages produits, afin de confirmer l’aptitude de la présure extraite dans les conditions optimisées, à remplacer avec succès la chymosine. Cette dernière partie visait également à sélectionner une concentration en sel appropriée au cours du saumurage, pour obtenir une meilleure qualité du produit final. Par conséquent, les propriétés physico-chimiques, texturales et rhéologiques, ainsi que le niveau de protéolyse dans les fromages, saumurés à différentes concentrations en sel, ont été déterminés. Les résultats ont permis de sélectionner une concentration en sel de 15 %, pour la quelle d’excellentes propriétés ont été obtenues, en termes de rendement fromager, texture et viscoélasticité après 28 jours de stockage (4°C). En conclusion, la présente thèse a contribué par l’optimisation des conditions d’extraction, à la production d’un extrait enzymatique doté d’une activité spécifique maximale, permettant de produire d’excellentes qualités de coagulums et des fromages saumurés. Ces résultats satisfaisants pourraient offrir de nouvelles opportunités de production d’une « présure végétale » compétitive, par rapport aux enzymes animales ou microbiennes. [less ▲]

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See detailBeech wood Fagus sylvatica hydrolysates as feedstocks for Chlorella biomass, fatty acid and pigment production
Miazek, Krystian ULiege

Doctoral thesis (2018)

This thesis evaluates the possibility of using wood hydrolysates as feedstocks for microalgae growth and production of industrially valuable compounds such as fatty acids and pigments. Moreover, the ... [more ▼]

This thesis evaluates the possibility of using wood hydrolysates as feedstocks for microalgae growth and production of industrially valuable compounds such as fatty acids and pigments. Moreover, the effect of lignocellulosic hydrolysates, organic substances typically present in lignocellulosic hydrolysates, as well as minor co-products, on growth and accumulation of target compounds in microalgae cultures is described. Firstly, beech wood dilute-acid (H2SO4) hydrolysate as a feedstock for Chlorella growth, fatty acid and pigment production, was tested. Hydrolysis of beech wood with the use of sulfuric acid produced a hydrolysate containing numerous organic compounds such as sugars, acetate, phenolics and furans. In order to elucidate the effect of wood hydrolysate on Chlorella culture, different components of hydrolysate were tested separately or in the mixture. Amongst compounds tested, glucose and acetate supported Chlorella growth, xylose, mannose, galactose, 2-F and HMF were inhibitory, arabinose and rhamnose were neutral. Results of this thesis show that beech wood acid hydrolysate after neutralization with NaOH can strongly improve Chlorella growth at lower loadings due to the presence of acetate and glucose, readily consumed in Chlorella culture. However, the same hydrolysate added at higher loadings can be inhibitory or even lethal for Chlorella. Interestingly, compounds tested separately and identified as inhibitory for Chlorella growth, seemed not to be responsible for inhibitory effect of wood hydrolysate. They are either at concentrations too low to cause inhibition (2F, HMF, mannose, galactose) or their inhibitory effect is nullified in the presence of glucose and acetate (xylose, mannose). Neutralized sulfuric acid loadings caused inhibition of Chlorella growth. It shows that inorganic compounds added for preparation of wood hydrolysate can also affect microalgae growth. However, neutralized sulfates were only partially responsible for inhibitory activity of wood hydrolysate, showing that wood hydrolysate also contains other substances responsible for growth inhibition. Nevertheless, neutralized wood hydrolysate proved to support Chlorella growth during mixotrophic and heterotrophic cultivation, on condition that wood hydrolysate loading is optimized to avoid toxic threshold. This thesis shows that neutralized wood acid hydrolysate can be used as an organic carbon feedstock for microalgae to produce fatty acids and pigments. The addition of 12% wood hydrolysate (Hyd12%) into photoautotrophic culture, improved by nearly 100% fatty acid productivity in comparison to control. Moreover, pigment content in Chlorella culture growing on wood hydrolysate in the presence of light, was the highest from all carbon-based profiles. Supplementation of Chlorella culture with Hyd12% in dark resulted in fatty acid productivity at comparable level to photoautotrophic control, showing that wood hydrolysate can also become an alternative feedstock for microalgae cultivation in case of lack of light. Wood acid hydrolysate can serve as a supplement to improve fatty acid and pigment productivity during mixotrophic Chlorella cultivation. It can also constitute a source of carbon for fatty acid and pigment production during heterotrophic Chlorella cultivation, although it should be taken in consideration that the presence or lack of light was an important factor affecting composition of fatty acids and pigments in Chlorella culture, cultivated on a neutralized wood acid hydrolysate. Secondly, enzymatic beech wood hydrolysate as a feedstock for Chlorella growth, fatty acid and pigment production, was tested. Beech wood solids were pretreated with NaOH at high temperature to partially remove xylose and Klason lignin, and enable production of glucose during subsequent enzymatic hydrolysis. A 10% neutralized wood enzymatic hydrolysate containing glucose (TGP-Enz10), was tested on Chlorella growth during heterotrophic cultivation and compared with microalgae growth in a medium containing synthetic glucose (TGP). Results show that enzymatic hydrolysate enabled Chlorella growth in the dark for biomass, fatty acid and pigment production due to the presence of glucose, although the productivity obtained was smaller, if compared to heterotrophic cultivation in a synthetic TGP medium. Partial growth inhibition and diminished productivity in wood hydrolysate supplemented Chlorella culture was due to the presence of neutralized citrate buffer. Neutralized citrate buffer (TGP-Cit10) was found to partially inhibit heterotrophic growth and also strongly suppress mixotrophic growth in Chlorella culture. This buffer was also shown to alter fatty acid composition and to slightly affect ChlTotal/CarTotal ratio during heterotrophic cultivation. Heterotrophic Chlorella cultivation with TGP-Enz10 showed that wood enzymatic hydrolysate can constitute a potential feedstock for microalgae cultivation, although the composition of the buffer used during enzymatic hydrolysis should be taken into consideration. Finally, advantages and disadvantages of using different wood hydrolysates as feedstocks for microalgae cultures, are discussed. [less ▲]

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See detailAspects of acoustic communication in Serrasalmidae
Melotte, Geoffrey ULiege

Doctoral thesis (2018)

In Teleostei, the evolution of the ability to produce sounds has provided a great diversity of sonic mechanisms, even at the intrafamilial level. However, the constraints modulating the evolution of sound ... [more ▼]

In Teleostei, the evolution of the ability to produce sounds has provided a great diversity of sonic mechanisms, even at the intrafamilial level. However, the constraints modulating the evolution of sound-producing mechanisms and hearing structures are very little supported by comparative anatomy studies and it is not determined in fish if the evolutionary constraints are related to intraspecific communication or environmental characteristics. Serrasalmidae (Characiformes) are neotropical freshwater fishes inhabiting most of the major river systems in South America. This family is currently divided into three clades: the « pacu », the « Myleus » and the « piranha » clades. The ability to produce sounds has been reported in some species belonging to the « piranha » clade, within the genera Pygocentrus and Serrasalmus. The ability to detect sounds has been reported only in Pygocentrus nattereri. This thesis aims to improve our knowledge on acoustic communication in the family Serrasalmidae. The main goal was to determine, in a phylogenetic context, whether soundproducing and -detecting apparatuses coevolved within this family. The hypothesis is that the species having developped the most complex sound-producing mechanisms also improved their ability to discriminate different types of sounds. An alternative hypothesis is that auditory ablities are more related to the biology of fishes: carnivorous species would have better hearing than herbivorous species to locate their living prey. The ability to produce and detect sounds was therefore investigated using different techniques in a large panel of serrasalmid species. The ability to produce sounds is uneven in the family Serrasalmidae. In the « pacu » clade, Piaractus brachypomus produces single low frequency pulses by contracting its hypaxial musculature. In the « Myleus » clade, several species belonging to the genera Myleus and Myloplus produced no sound, whatever the experimental conditions. In the « piranha » clade, Pygopristis denticulata and Catoprion mento produce sounds composed of a varying number of pulses. They possess a sonic muscle extending from the second rib to the first rib (P. denticulata) or to the swimbladder (C. mento). Pygocentrus spp. and Serrasalmus spp., as well as Catoprion mento, are able to utter drumming sounds (tonal vocalizations characterized by the presence of harmonics in the power spectrum) when hand-held. Sonic muscles of the genera Pygocentrus and Serrasalmus originate at the base of the second rib and attach to a tendon surrounding the swimbladder ventrally. Investigation of the auditory system morphology in various serrasalmid species showed that the hearing structures (otoliths and Weberian ossicles) are similar in overall shape and position in all the species investigated. Moreover, hearing range and hearing sensitivity are quite comparable among the species, despite differences in life-history traits (vocal vs. nonvocal and herbivorous vs. carnivorous species). Therefore, hearing capacities are not related to the ability to produce sounds or to the diet. Acoustic communication appears to be of importance within carnivorous species since the most sensitive hearing range covers the frequency spectrum of acoustic signals. However, hearing ability is not related to the capacity to emit sounds. The auditory system seems to be highly conserved within this family, suggesting that it was shaped by other constraints than acoustic communication. Sonic organs developed secondarily in the most derived species and could be related to their radiation. [less ▲]

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See detailDesign of poly(HEMA) particles in supercritical carbon dioxide for protein delivery
Parilti, Rahmet ULiege

Doctoral thesis (2018)

A vast majority of the polymer nanocarriers have been designed and developed for the controlled and targeted release of hydrophobic drugs. However, there are still some challenges to design appropriate ... [more ▼]

A vast majority of the polymer nanocarriers have been designed and developed for the controlled and targeted release of hydrophobic drugs. However, there are still some challenges to design appropriate carriers for the delivery of therapeutic proteins or peptides. Although the history of the protein/peptide based drugs dates back to insulin production, they have taken great attention since the last decades due to their possible broad range of therapeutic applications. They might offer more specific and safer therapies in comparison to small molecules drugs. Nonetheless, their encapsulation remains challenging especially to preserve their specific structure and activity in the formulations. For this purpose, hydrogel particles (nano-/microgels) have emerged as promising polymer carriers for such proteins. This work focuses on the synthesis of nano-/microgels encapsulating therapeutic proteins and peptides in supercritical carbon dioxide which confers environmentally benign features to the synthesis method. More precisely, hydrogel particles were obtained by free-radical dispersion polymerisation of 2-hydroxyethyl methacrylate (HEMA) in supercritical carbon dioxide in presence of a cross-linker and a suitable stabiliser. Two kinds of stabilisers have been designed and studied, i.e. a photocleavable perfluorinated stabiliser and a fluorine-free stabiliser. The optimisation of the dispersion polymerisation conditions led to well-defined cross-linked particles. The process was robust enough to incorporate a drug or a peptide to encapsulate in one-pot synthesis into the particle network. In a subsequent step such drug loaded particles were dispersed successfully in aqueous media and shown sustained release of their content. This was demonstrated notably for the release of a bactericidal peptide. [less ▲]

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See detailRobust Multivariate Dispersion Measures
Aerts, Stéphanie ULiege

Doctoral thesis (2018)

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See detailEvolution et adaptation fonctionnelle des arbres tropicaux : le cas du genre Guibourtia Benn.
Tosso, Dji-ndé Félicien ULiege

Doctoral thesis (2018)

La présente thèse s’intéresse aux mécanismes à l’origine de la diversification des espèces d’arbres tropicaux. Elle utilise le genre Guibourtia Benn. (Fabaceae-Detarioideae) comme modèle biologique afin ... [more ▼]

La présente thèse s’intéresse aux mécanismes à l’origine de la diversification des espèces d’arbres tropicaux. Elle utilise le genre Guibourtia Benn. (Fabaceae-Detarioideae) comme modèle biologique afin de comprendre les mécanismes historiques, biologiques et environnementaux, à l'origine de la diversité de ce genre aux niveaux interspécifique et intraspécifique. Plus particulièrement, elle vise à : (1) étudier au niveau interspécifique, le rôle relatif des forces évolutives neutres et de sélection dans la diversification du genre Guibourtia en combinant une phylogénie moléculaire avec la caractérisation des traits et les niches écologiques des espèces ; et (2) au niveau intraspécifique, questionner les causes de la différenciation des populations de trois espèces de Guibourtia. Au niveau interspécifique, la phylogénie datée basée sur le séquençage du génome chloroplastique complet a globalement confirmé la taxonomie actuelle (espèces généralement monophylétiques). Elle a montré une diversification au milieu du Miocène en trois clades qui sont décrits aujourd’hui comme des sous-genres (Guibourtia, Gorskia et Pseudocopaiva). Elle démontre en outre que deux espèces américaines sont issues d’une migration de l’Afrique vers l’Amérique à la fin du Miocène. Il est également apparu que certains traits morphologiques ont été sélectionnés de manière convergente au sein des différents clades du genre Guibourtia en fonction des niches climatiques des espèces. Ce dernier résultat a été consolidé au moyen d’une expérimentation écophysiologique prouvant que la lumière constitue un important facteur de sélection et de différenciation adaptative entre trois espèces (G. ehie, G. coleosperma et G. tessmannii). Au niveau intraspécifique, une étude de phylogéographie de deux espèces a permis de mettre en évidence que les barrières biogéographiques chez G. ehie et les gradients climatiques chez G. coleosperma, auraient contribué à la différenciation génétique des populations. En outre, cette étude montre une forte différenciation entre les populations de G. ehie d’Afrique de l’Ouest et d’Afrique centrale en lien avec quelques traits morphologiques, ce qui préjuge de l’existence d’une nouvelle espèce. Enfin, chez G. tessmannii, espèce aux fruits déhiscents et graines arillées, nous avons identifié les principaux disperseurs dont les calaos (Ceratogymna atrata ) qui pourraient contribuer à une dispersion à longue distance, influençant la structure spatiale de la variation génétique des populations. Cette thèse en utilisant le genre Guibourtia comme modèle d’étude a apporté de nouveaux éléments à la compréhension des mécanismes qui génèrent la diversité au sein des espèces d’arbres. Elle fournit en outre des connaissances originales sur des espèces inscrites en annexe II de la CITES. [less ▲]

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See detailGenetic Relationships between Methane-related Traits and Milk Composition in Lactating Dairy Cows
Kandel, Purna ULiege

Doctoral thesis (2018)

Methane (CH4) emission is one of the most important environmental traits from dairy cows. Genetic selection programs aiming to mitigate CH4 emissions require the estimation of genetic parameters ... [more ▼]

Methane (CH4) emission is one of the most important environmental traits from dairy cows. Genetic selection programs aiming to mitigate CH4 emissions require the estimation of genetic parameters, correlations with other economically important traits and predicted selection response of these traits. In first part of this thesis, CH4 emissions (g/d; PME) were predicted from several milk fatty acid based prediction equations using mid-infrared (MIR) spectra of milk samples from Holstein cows. The heritability of PME was moderate and ranged from 0.21 to 0.40. The sires genetic variability were large enough to respond selection pressure. In second part and to minimize prediction errors, genetic parameters were estimated from direct prediction of CH4 (i.e. based on SF6 measurements) from milk MIR spectra. Predicted CH4 intensity (PMI, g/kg of milk) was derived from the ratio of CH4 (g/d) value divided by the total milk yield recorded for the considered test-day which is a trait that is comparable across different production systems. The relationship between PMI and milk yield (MY) was curvilinear and the distribution of PMI being non-normal, it was log-transformed (LMI) in further analyses. The genetic analyses were performed using two genetic models with or without random within-herd lactation curve effects along with random permanent and additive genetic effects. The results showed that the model with random within-herd lactation curve effects had a better fitting. The heritability of PME was 0.26 and PMI was 0.27. The contribution of random herd-specific lactation curve effects to the total variance also suggested an impact of herd specific management on the CH4 emission traits. After confirming genetic component of CH4 traits, genetic correlations of these traits with milk production traits were explored and expanded to second lactation. The phenotypic correlations between PME and MY, fat yield and protein yield were not different than zero but with LMI, the phenotypic correlations were highly negative. The genetic correlation was low negative between PME and milk production traits but high negative with LMI. The intra-lactation heritability and correlation were changing across lactation suggested there was dynamic relationship between CH4 traits and milk production traits. After demonstrating correlation between milk production traits, the genetic correlation between CH4 traits and functional traits [fertility, body condition score (BCS), longevity], health traits (udder health) and type traits were estimated. There were positive correlations between CH4 emission traits and functional trait suggested there were tradeoffs between these traits in selection. The ingestion ability related type traits had positive genetic correlations with PME but negative genetic correlation with LMI. Finally, using the current Walloon selection index and by selecting PME and LMI, the emission traits responded by a reduction in CH4 emission, without jeopardizing in milk production traits but having negative consequences in fertility, BCS and longevity. In conclusion, this study shows the feasibility to adapt the selection index to mitigate the CH4 emitted by dairy cows. [less ▲]

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See detailFreezing: An ethnography of crisis reporters
Kotisova, Johana ULiege

Doctoral thesis (2018)

RÉSUMÉ La thèse examine la composition technologique des émotions des journalistes face à une situation de crise. Les émotions liées au travail des journalistes sont au cœur du paradoxe posé, d’une part ... [more ▼]

RÉSUMÉ La thèse examine la composition technologique des émotions des journalistes face à une situation de crise. Les émotions liées au travail des journalistes sont au cœur du paradoxe posé, d’une part, par un engagement journalistique traditionnellement en faveur de l'objectivité - celle-ci étant entendue comme une forme de détachement, de neutralité et d'impartialité – et, d’autre part, une obligation morale d'action face à la souffrance humaine. Il s'en suit que les émotions des journalistes face à une situation de crise constituent un élément crucial de notre compréhension des pratiques journalistiques et de leurs conséquences en temps de crise. En s'appuyant sur les notions de 'crise', 'émotion' et 'technologie', j'aborde les questions suivantes : Que signifie la notion de 'crise' dans le rapport du journaliste à la crise ? Quelle est l'expérience émotionnelle d'un journaliste travaillant sur un lieu de crise ? Comment la technologie façonne-t-elle l'expérience émotionnelle de la crise par le journaliste ? Mon itinéraire de recherche se veut résolument opportuniste et se base sur une enquête ethnographique multi-sites consistant principalement en un travail d'observation participante (cinq mois dans trois salles de rédactions de trois médias tchèques) et en trente-trois entretiens approfondis avec de 'grands reporters' tchèques et belges (c’est-à-dire avec des journalistes envoyés sur le terrain de certaines attaques terroristes, guerres, catastrophes naturelles et autres situations de crise). L'analyse démontre comment la présence directe ou médiatisée sur le terrain de crise provoque des sentiments de tristesse, d'indignation, de pitié, de colère, de peur, de stress, de tension, de compassion, d'effroi et d'épuisement. Toutefois, ces émotions sont supprimées ou réprimées. Le fait de devoir rapporter régulièrement sur des événements perturbants ou de témoigner de la douleur proche ou lointaine peut aboutir à la formation de styles émotionnels spécifiques. Parmi ceux-ci, le cynisme occupe une éminente position. Les émotions des journalistes sont liées de façon inaliénable aux caractéristiques intrinsèques de leur profession, mais aussi aux situations de crise et à la l’industrie journalistique, c’est-à-dire à l'ensemble de techniques de production, aux techniques de systèmes de signes, aux techniques de pouvoir et aux techniques de soi. En même temps, la prise en compte de ces émotions entre en tension avec la conception traditionnelle du journaliste professionnel ‘observateur plutôt qu'acteur’ dont l'objectivité constituerait un pilier majeur de professionnalisme. Fondée sur l’analyse des discours à partir desquels les journalistes interprètent (« make sense ») leur développement émotionnel, la thèse questionne également le sens des notions de 'crise', 'émotion' et 'technologie' dans le contexte spécifique du journalisme en situation de crise. La crise est ainsi redéfinie comme une source de propagation de l'idéologie cynique ; l'émotion comme une sensation non-individuelle et non-intime d’individualisation des problèmes sociaux ; et la technologie comme appui permettant la manipulation de toutes les formes de vie. Ces trois redéfinitions permettent ensuite d’entreprendre une analyse critique de l'idéologie professionnelle des journalistes ainsi que de la critique de l'inaction des institutions, médiatiques notamment. Je propose enfin de reconnaitre et d’encourager l'engagement émotionnel (explicite) des journalistes et de redéfinir la notion d'objectivité comme une pratique éthique plutôt qu'une norme objectiviste. Ceci contribuerait en effet à réduire de la dissonance émotionnelle des journalistes et à dépasser le cynisme caractéristique des organisations médiatiques et de leur travail. La thèse, rédigée sous forme de récit, livre, selon une trame narrative fictionnelle, un exposé du matériau empiriquement collecté. Cette forme d'écriture (« créative nonfiction ») remplit cinq fonctions qualifiées d’illustrative, allégorique, organisatrice, effective et auto-réflexive. [less ▲]

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See detailHierarchical porous TiO2 and ionic liquid-like polysiloxane electrolyte for solid state-Dye-Sensitized Solar Cells
Bharwal, Anil Kumar ULiege

Doctoral thesis (2018)

DSSC is a 3rd generation photovoltaic technology with potential to economically harvest and efficiently convert photons to electricity. Full solid state-DSSC based on solid polymer electrolyte prevents ... [more ▼]

DSSC is a 3rd generation photovoltaic technology with potential to economically harvest and efficiently convert photons to electricity. Full solid state-DSSC based on solid polymer electrolyte prevents the solvent leaking and evaporation during cell fabrication and operation, which will effectively prolong the cell life time. However, it suffers from low ionic conductivity and poor pore infiltration. The present thesis is dedicated to the concomitant development of polysiloxane-based polymer electrolytes on one side, and TiO2 photoanodes with tuned porosity on the other side, and their incorporation in solid-state dye-sensitised solar cell (ss-DSSCs), with the aim to improve their photovoltaic efficiency and the long term stability. To best of our knowledge, DSSCs comprising bimodal TiO2 layers and polysiloxane electrolytes have never been reported. The ionic conductivity and tri-iodide diffusion coefficient of the polysiloxane-based poly(ionic) liquids (PILs) were largely improved by adding of ionic liquids (ILs) or et hylene carbonate (EC), achieving ionic conductivities of 10−4 -10−3 S cm−1. The DSSCs fabricated with the optimized electrolytes showed efficiencies up to 6%, with long term stability for 250 days. Bimodal TiO2 films with dual porosity (meso- and macro-porosity) were fabricated by spin-coating, by using soft and hard templating. The dual templated films benefit from increased pore size while maintaining high surface area for dye adsorption. Bimodal films were shown to be more efficient when tested with polymer electrolytes, having comparable efficiencies with liquid electrolyte when in DSSCs, despite lower dye uptake. This thesis brings a significant contribution to the field of DSSCs as efficient and stable solar cells were prepared from newly synthesized polymer electrolytes and bimodal films. [less ▲]

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See detailGenomics, Metagenomics and Phylogenomics of Cyanobacteria
Cornet, Luc ULiege

Doctoral thesis (2018)

This PhD thesis concerns the genomics, metagenomics and phylogenomics of Cyanobacteria. It is composed of five main parts, of which four are result manuscripts. In the first part (i.e., Introduction), I ... [more ▼]

This PhD thesis concerns the genomics, metagenomics and phylogenomics of Cyanobacteria. It is composed of five main parts, of which four are result manuscripts. In the first part (i.e., Introduction), I review a decade of cyanobacterial phylogeny and molecular dating. I show that, in spite of a considerable literature, the global topology of the cyanobacterial tree is incongruent across 9 of the 12 recent studies. I also raise the issue that cyanobacterial datings are all based on ambiguous fossils, since no genomic data are available for unambiguous fossil calibration points. The second part deals with the problem of public genome contamination. I analyzed 440 genomes of Cyanobacteria with a consensus approach of five methods (two based on ribosomal genes and three based on complete genome analysis), and determined that >5% cyanobacterial genomes are contaminated by foreign DNA. The next two parts are metagenomic analyses. The first metagenomic study is a pipeline for properly assembling complete genomes from non-axenic cultures. To this end, I used 17 cyanobacterial cultures from the BCCM/ULC collection of the ULiège and assembled metagenomic reads into 15 genomes with a very low level of contaminants and a high level of completeness. The second metagenomic study deals with the new field of phylometagenomics. Hence, I developed a new syntenic algorithm designed for metagenomes in mind, and applied it to the study of lichenized Cyanobacteria. I found 90 syntenic and collinear genes shared between 28 Nostocales genomes, including 12 new photobiont metagenomes. The subsequent phylogenetic analysis showed a relatively high level of congruence among these genes. Finally, the last part of the thesis is a large constrained SSU rRNA (16S) tree intended to serve as a guide in organism selection for future sequencing projects. It revealed 31 clusters of Cyanobacteria that are completely devoid of representative genomes (<0.1%). Altogether, the results of this PhD work lay the ground for a better phylogenomic study of the Cyanobacteria, taking advantage of new key organisms. [less ▲]

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See detailLa Lydie d'Alyatte et Crésus. Un royaume à la croisée des cités grecques et des monarchies orientales. Recherches sur son organisation interne et sa politique extérieure
Leloux, Kevin ULiege

Doctoral thesis (2018)

This dissertation analyzes the internal organization and the foreign policy of the Lydian Kingdom under Alyattes’ and Croesus’ reigns. It is under those two sovereigns’ authority that the Lydian Kingdom ... [more ▼]

This dissertation analyzes the internal organization and the foreign policy of the Lydian Kingdom under Alyattes’ and Croesus’ reigns. It is under those two sovereigns’ authority that the Lydian Kingdom will reach its peak. At that time, the Kingdom was divided into several regions ruled by a governor who was to provide military contingents to Sardis when the king expressed the need. Croesus was sent by his father to rule the district of Adramytteion, a strategic sector, because he was probably not intended to be his father’ successor. This is only after the death of his half brother Pantaleon that Croesus managed to be appointed as the legitimate successor. The two last Mermnads have mainly made agreements with the Eastern Greeks. Alyattes had bounded hospitality links with the different coastal cities. On its side, Croesus imposed them a payment of a tribute, and a shipment of military forces to Sardis. Only Miletos managed to save face extending the links of ξενία concluded with Alyattes. For the Mainland Greeks, it seems that Alyattes never bounded any relations with the Tyrants of Corinth. On the other hand, Croesus may well have conclued agreements, probably links of ξενία, with Sparta. In the West, Alyattes took control over Phrygia, weakened by the Cimmerian raids, on his march against the Medes. This Lydo-Median war ended with a friendship treaty and a non-agression agreement, likely renewed under Croesus. This king also came into contact with Amasis of Egypt and Nabonid of Babylon. The agreements close to those of Greeks’ ξενία, had the intentions to serve everyone’ commercial interests. Finally, during his campaign against Pteria, Croesus met the Persians. His defeat in Cappadocia rushed his retreat to Sardis and the capture of the capital by the Persian troops. It was during this siege of the city that Croesus committed suicide. The fall of Sardis leaded to the incorporation of the Greek cities in the Persian Empire and later to the Ionian revolt, a prelude to the Greco-Persian Wars. The simultaneous fires of Sardis and the Apollo temple in Delphi, both dated 547 BC, may well have inspired the Delphian priests and the episode of Croesus on the pyre, in order to enhance the sanctuary’ aura [less ▲]

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See detailLa Deuxième Guerre mondiale au Rwanda (1939-1945) : impact du conflit sur les populations
Singiza, Dantès ULiege

Doctoral thesis (2018)

Intending to contribute to the history of central Africa during World War II, we proceed through a case study : the impact of the conflict on the populations of Rwanda, then under the mandatory power of ... [more ▼]

Intending to contribute to the history of central Africa during World War II, we proceed through a case study : the impact of the conflict on the populations of Rwanda, then under the mandatory power of Belgium. Although being a key period in the evolution of Rwanda, the years 1939-1945 have received scant attention from historians. Our study combines several aspects : political, sociological, economical, religious or even military. It includes the Rwandese participation in the « war effort » and the military operations (enlistments in the Force Publique and the British units). A thorough study explores the consequences of war on the society, the economy as well as the ecological equilibrium of the country (famines, modifications in agriculture, population moves, changes in habits). The last set of questions focuses on the impact of the conflict on different levels of authority (mandate officials, local chiefs, church leaders), on the evolution of their image in the eyes of the Rwandese and on the state of mind of the latter at the end of the war. [less ▲]

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See detailDevelopment of an attenuated recombinant vaccine against Cyprinid herpesvirus 3
Boutier, Maxime ULiege

Doctoral thesis (2018)

The cyprinid herpesvirus 3 (CyHV-3, genus Cyprinivirus, family Alloherpesviridae, order Herpesvirales) is the aetiological agent of a highly contagious and lethal disease affecting koi and common carp ... [more ▼]

The cyprinid herpesvirus 3 (CyHV-3, genus Cyprinivirus, family Alloherpesviridae, order Herpesvirales) is the aetiological agent of a highly contagious and lethal disease affecting koi and common carp (Cyprinus carpio). Common carp is currently the third most important fish species of aquaculture with a world production between 3 and 5 million tons per year. A safe and efficacious attenuated vaccine compatible with mass vaccination is needed to control CyHV-3. In this thesis, we produced an ORF56-57 double deleted (Δ56-57) attenuated recombinant vaccine candidate using prokaryotic mutagenesis. The safety of this vaccine candidate was demonstrated using in vivo bioluminescent imaging system (IVIS), qPCR, and histopathological examination. In comparison to the parental wild type strain, the vaccine candidate replicated at lower levels and spread less efficiently to secondary sites of infection. Transmission experiments allowing contamination through water with or without additional physical contact between fish demonstrated that the vaccine candidate has a reduced ability to spread from vaccinated fish to naïve sentinel cohabitants. Finally, challenge experiments demonstrated that the vaccine candidate induces a protective mucosal immune response at the portal of entry. The first part of this thesis led to the rational development of a recombinant attenuated vaccine against CyHV-3 compatible with mass vaccination of carp. In the second part of this thesis, the relative contributions of ORF56 and ORF57 to the safety and efficacy profile of the Δ56-57 vaccine candidate have been assessed by producing and phenotyping viruses individually deleted for ORF56 or ORF57. Inoculation of these viruses to carp demonstrated that the deletion of ORF56 did not affect virulence, whereas the absence of ORF57 led to an attenuation comparable to, though slightly less than, that of the Δ56-57 vaccine candidate. To demonstrate further the role of ORF57 as a key virulence factor, a mutant retaining the ORF57 region but unable to express the ORF57 protein was produced by inserting multiple in-frame stop codons into the coding region. Analysis of this virus in vivo revealed a safety and efficacy profile comparable to that of the double deleted virus. These findings show that CyHV-3 ORF57 encodes an essential virulence factor. CyHV-3 is considered as the prototype of the genus Cyprinivirus which encompasses a growing list of phylogenetically related viruses causing massive economical losses to the aquaculture sector. This thesis led for the first time to the identification of an essential virulence factor of CyHV-3 and to the demonstration that recombinant viruses deleted for this gene are potential vaccine candidates. All cypriniviruses described to date encode orthologues of CyHV-3 ORF57. Consequently, the present work opens new perspectives for the development of recombinant attenuated vaccines against this economically important viral genus. [less ▲]

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See detailDébit de filtration glomérulaire : Détermination de formules d’estimation adaptées à l’adulte noir ouest-Africain
Yayo, Sagou Eric-Didier ULiege

Doctoral thesis (2018)

La maladie rénale chronique (MRC) est reconnue comme un problème de santé publique. L’estimation du débit de filtration glomérulaire (DFG) est une donnée fondamentale à son dépistage et à sa prévention ... [more ▼]

La maladie rénale chronique (MRC) est reconnue comme un problème de santé publique. L’estimation du débit de filtration glomérulaire (DFG) est une donnée fondamentale à son dépistage et à sa prévention particulièrement dans les pays Africains au sud du Sahara où les moyens de prise en charge de la maladie sont limités. Or dans les principales formules (MDRD et CKD-Epi) recommandées pour la détermination du DFG chez les Africains, un facteur ethnique est actuellement appliqué. Cependant, ces facteurs ont été déterminés à partir de l’étude de sujets afro-américains (AA) et leur validité chez le sujet africain (non américain) reste une question. Le présent travail a visé à déterminer la valeur de référence du DFG par une méthode de référence en population générale noire, ouest-africaine et à évaluer la pertinence des équations d’estimation actuellement en vigueur. L’étude a porté sur 254 Ivoiriens adultes présumés sains (120 femmes et 134 hommes). Chez chaque participant, le DFG a été mesuré par la clairance plasmatique de l’iohexol et estimé par les formules de CG, MDRD et CKD-Epi (à base de créatinine et/ou cystatine C). Les performances des équations d’estimation ont été évaluées à partir du biais, de la précision et de l’exactitude. A l’issue de nos travaux, les valeurs de référence de DFG ont été établies en population noire Africaine à partir d’une méthode de référence. Elles sont de l’ordre de 104 ml/min/1,73m2. Concernant les formules d’estimation, l’usage du facteur actuel donne une surestimation systématique des résultats du DFG estimé et devrait être abandonné. Il ressort également que la formule CKD-Epi sans facteur AA présente les meilleures performances pour l’estimation du DFG chez l’adulte noir Africain. Enfin, l’introduction de la cystatine C dans les différentes équations d’estimation n’a pas apporté de valeur ajoutée significative par rapport à la créatinine dans notre cohorte. [less ▲]

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See detailLe suffixe */-'ur-a/ : recherches sur la morphologie dérivationnelle du protoroman
Mertens, Bianca ULiege

Doctoral thesis (2018)

This thesis is dedicated to studying the Protoromance suffix */-'ur-a/ and, hence, to studying derivational morphology of Protoromance. On the one hand, we provide an extensive and detailed exam of ... [more ▼]

This thesis is dedicated to studying the Protoromance suffix */-'ur-a/ and, hence, to studying derivational morphology of Protoromance. On the one hand, we provide an extensive and detailed exam of Protoromance lexical units presenting the suffix */-'ur-a/ and, on the other hand, we produce a thorough analysis of the phonological, morphological and semantic properties of the suffix */-'ur-a/. The first part of this work consists of a short introduction and of the presentation of the methodology that we used in our research : the methodology of compared reconstruction and of internal reconstruction. Then, we focus on the two fields that are particularly interesting in the context of studying a Protoromance suffix : reconstruction in Romance studies and morphological reconstruction. This first part closes up with an explanation of our nomenclature – including a short analysis of the rejected words –, a specification of our research process and a presentation of the microstructure used for our etymological articles. In the second part of our thesis appear the etymological articles of all 45 Protoromance etymons with the suffix */-'ur-a/ that we were able to reconstruct. Each etymological article comes with a linguistic map that provides a global view of the geographical distribution of the concerned etymon. Finally, the third part of our work is a thorough and detailed analysis of the phonological, morphological and semantic properties of the Protoromance suffix */-'ur-a/ and of the diasystemic variation of the Protoromance language. [less ▲]

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See detailParents d'un enfant en rémission de cancer: Prédicteurs psychologiques et cognitifs de l'intolérance à l'incertitude dans le maintien des inquiétudes et dans l'orientation de l'attention sélective
Vander Haegen, Marie ULiege

Doctoral thesis (2017)

In spite of core medical advances realized these last years, the childhood cancer remains a distressing experience for the child and their parents. The cancer history is rarely linear and takes place into ... [more ▼]

In spite of core medical advances realized these last years, the childhood cancer remains a distressing experience for the child and their parents. The cancer history is rarely linear and takes place into a space and a particular time when marks are shaken. The stake in paediatric oncology is double: that the child is cured without side effects and that the child and parents cross this experience without psychological destabilization. When the cancer survivorship is diagnosed, new challenges are expecting for the child and parents. Indeed, the childhood cancer survivorship is considered as integrated into the field of chronic diseases where the factor of uncertainty coexists and requires continuous adjustments of the child and parents. Therefore, it is a period of progressive rehabilitation where the stake is double: control the relapse and treatments’ late effects (or aftereffects) of the child and allow the child and parents, “to pursue their life the most normally possible”. The survivorship experience is thus intense transforming deeply “the psyche” of the child and parents. Since a few years, empirical studies examine the child adjustment and parents in the course of treatments. These reveal namely some adaptation difficulties, anxious and depressive symptoms. However, the social/family support and the problem-focused coping seem positively moderate the distress intensity. Studies investigated the cancer survivorship were mainly centred on the child and showed its effects on the child’s psychological adjustment (e.g. anxiety, depression). Nevertheless, the distress intensity could be positively influenced in particular by social and family support factors. The thorough examination of the literature observes that studies rarely include the parent and that no study has associated the factor of uncertainty with the vulnerability factor of intolerance of uncertainty. The originality of this research lives in the interest centred on the concept of intolerance of uncertainty [IU] and its effects on the psychological and cognitive adjustment among parents of a child cancer survivor. This quasi-experimental, quantitative, longitudinal research combines standardized questionnaires (IUS, NPOQ, CAQ, Mini-CERTS, HADS, and WW-II), questionnaires created for the needs of the study (sociodemographic, QIPS-R15, OncoMed and SomaOnco) and two neuropsychological tasks (classic Stroop and emotional Stroop). The sample consists of 61 parents (45 mothers and 16 fathers) of a child cancer survivor (from 4 to 6 years of survivorship without relapse and with mainly a neoadjuvant chemotherapy during treatments). Three months later, parents returned to the laboratory and completed the same questionnaires and performed Stroop tasks (with the exception of words which are modified). The time was decided with medical teams. It seemed relevant to retest parents when the medical assessment of the child was completed in order to observe if the distress decreased. Besides, this time was sufficient to avoid memory biases. The first aim of this research is the study of parental distress. The proposed hypothesis is the existence of anxious, depressive, somatic symptoms and worries. Results showed that 70 % of parents had anxious symptoms (HADS), 39 % presented depressive symptoms (HADS), 14 % suffered from somatic symptoms (SomaOnco) and 70 % had worries (QIPS-R15). Results from moderation analyses indicated no main effect of gender, remission time, and couple on distress criteria (except the interaction of these three factors for worries). These results demonstrated the existence of a significant distress within the sample but also the presence of additional factors which may influence the parental adjustment. The second aim is the examination of IU and its maintaining factors (i.e. positive beliefs about worry, cognitive avoidance, negative attitude towards problems and repetitive thinking (ruminations)). The advanced hypothesis is the causal track between IU and its maintaining factors. Results of IUS questionnaire demonstrated on average that parents had a low tolerance of uncertainty (64 % of the sample) and that 60 % of the sample were located in a moderated to severe profile of generalized anxiety disorder (GAD). Concerning IU’s maintaining factors, results of NPOQ, CAQ, WW-II and Mini-CERTS questionnaires highlighted the existence of positive beliefs towards worry (WW-II: problem solving and positive trait of personality) and cognitive avoidance (CAQ: distraction and thought suppression). Results of regressions bear out the predictor status of IU for the development of its maintaining factors. Nevertheless, protective factors arose from analyses, particularly an effective problem orientation and the use of concrete experiential thinking mode (CET; Mini-CERTS), which could protect them from a deterioration of the mood (e.g. depression). These results indicated the negative influence of IU on the psychological adjustment, the protective effect of a positive attitude orientation and the use of CET among parents. The third aim concerns the study of cognitive processes in terms of orientation of selective attention and cognitive inhibition. The proposed hypothesis is the orientation of selective attention towards threat into the IU context. Results seem to indicate a longer latency for negative and coloured words during Stroop tasks. The within-group regression and mediation results reveal the mediating effect of IU between the orientation of selective attention towards threat and distress components (i.e. anxious, depressive, somatic symptoms and worries). Moreover, depressive symptoms contribute to predicting the coloured word latency (cognitive inhibition process). These results seem to demonstrate the negative influence of the IU on the orientation of selective attention and depressive symptoms for cognitive inhibition. Lastly, the fourth aim is the analysis of IU stability and its maintaining factors over time. The proposed hypothesis is the stability of IU and its maintaining factors because IU is considered as a feature of the personality. At the second assessment (n=51/N=61), three significant differences were observed. The first difference concerns a decrease for anxiety symptoms with nevertheless a score being located in the pathological border. The second difference relates to a decrease for the cognitive avoidance with a score situated in the superior border of the standards. Lastly, an increase for somatic symptoms level was observed at the second assessment. Concerning IU, results indicate no significant change. Parents who presented a high level of IU at the first assessment kept it at the second assessment. This observation is also true for parents who had a low level of IU. These results supported the hypothesis of IU stability and its maintaining factors over time. Overall, results emphasize the implication of IU in the psychological distress among parents and its effect on cognitive processes of the orientation of selective attention towards threatening words (negative words). This research brings out the necessity to identify parents who are at risk for IU (and its maintaining factors) at an early stage of the cancer management in order to avoid excessive worries and the use of dysfunctional strategies over time. Furthermore, this research allows future clinical avenues for the development of follow-up tools in paediatric oncology, and recommends the parents’ psychological adjustment follow-up in close collaboration with medical teams. Implications of this research are discussed into the "general discussion" part of the thesis. [less ▲]

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See detailDetermining astrophysical parameters of quasars within the Gaia mission
Delchambre, Ludovic ULiege

Doctoral thesis (2017)

Quasars are one of the most peculiar types of objects in astronomy. The supermassive black hole these harbour effectively makes the surrounding matter radiates an enormous amount of energy before getting ... [more ▼]

Quasars are one of the most peculiar types of objects in astronomy. The supermassive black hole these harbour effectively makes the surrounding matter radiates an enormous amount of energy before getting in the vicinity of the black hole horizon out of which it will never escape. This ironically leads to the most luminous phenomenon in the Universe while being non-transient. It is hence quite natural to rely on these cosmic headlights, visible up to ages when the Universe was still very young, so as to achieve some of the currently most important cosmological applications, notably regarding the determination of the cosmological parameters $H_0$, $\Omega_\Lambda$ and $\Omega_m$. The Gaia mission, on its side, is one of a kind given the one billion of celestial objects it is intended to observe, among which more than half a million quasars are expected. Furthermore, owing to its exceptional astrometric precision, Gaia stands out to be extremely well suited for the detection of gravitational lens (GL) systems. In the latter, light rays coming from a distant background quasar are deflected by the presence of a massive galaxy being in the line-of-sight that leads to the production of multiple images of this background quasar upon a favourable alignment between the quasar, the galaxy and the observer. Supplemental constraints on the aforementioned cosmological parameters being then gained based on these GLs. Gaia hence provides an unprecedented opportunity to detect and characterize quasars as well as to identify GLs which ultimately bring a better understanding of the Universe we live in. This thesis is accordingly concerned with the development of software solutions dedicated to the determination of the astrophysical parameters (APs) of the quasars that Gaia will observe, on one hand, and to the recognition of the GLs among the billion of sources it will uncover, on the other hand. Although Gaia provides state-of-the-art astrometric and photometric observations, its capability in characterizing these celestial objects remains however restricted by the relatively low spectral resolution of the blue and red spectrophotometers upon which it is based as well as by the limited signal-to-noise ratio that is associated with faint objects, including quasars. In addition, the overwhelming amount of data that Gaia has to process translates into a stringent need for algorithms having both low numerical complexities as well as low memory usages. These restrictions and shortcomings along with the requirement for reliable APs were at the heart of this research that led to the development of two specifically designed methods that are the weighted principal components analysis and the weighted phase correlation method. The former of these methods allowed us to extract the most significant patterns out of quasars with a view of using these in the production of a spectral library of quasars as observed by Gaia. These were subsequently used in a fast and automated procedure designed to guess the redshift of the quasars within the Gaia mission through the latter mentioned method. Other APs that are the slope of the quasar continua, the total equivalent width of their emission lines and whether these encompass broad absorption lines or not, being then concurrently derived based on the results of these methods. Finally, the identification of GL candidates relies on the recognition of the structures and symmetries that are observed within lensed images through supervised learning methods. The specific method we choose to use, based on extremely randomized trees, was shown to yield a low contamination rate on simulated configurations composed of three images as well as a very high probability of detection in cases of four image configurations. Real observations out of the first Gaia data release were processed and resulted in the identification of candidates having three potentially lensed images which are currently waiting for confirmation using ground-based facilities. [less ▲]

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See detailInfluence d'une prise en charge posturale sur la position assise, les capacités cognitives, le comportement et le bien-être de l'enfant en classe
Fettweis, Tatiana ULiege

Doctoral thesis (2017)

Cette thèse analyse l’impact d’une prise en charge posturale associée à l’utilisation d’un coussin triangulaire dynamique sur la position assise, les capacités cognitives, la concentration et le bien-être ... [more ▼]

Cette thèse analyse l’impact d’une prise en charge posturale associée à l’utilisation d’un coussin triangulaire dynamique sur la position assise, les capacités cognitives, la concentration et le bien-être de l’enfant en début d'école primaire. Elle comporte 4 sections principales. La revue de la littérature présentée dans la première section souligne le rôle de l’école et plus spécifiquement l’impact du mobilier scolaire sur la santé et les apprentissages des élèves. La deuxième section consiste à mettre en place et à étudier les qualités métrologiques d’une batterie de tests permettant d’évaluer la qualité de la position assise, les capacités posturales, le comportement en classe et les capacités cognitives d’enfants du premier cycle du primaire. La troisième section comprend trois études de terrain évaluant l’influence de la prise en charge en milieu scolaire. La partie principale consiste en un suivi longitudinal réalisé au cours des deux premières années primaires. Dans ce cadre, le cousin dynamique a amélioré la qualité de la position assise, les plaintes musculo-squelettiques, les capacités cognitives et le comportement des enfants en classe. Une première étude complémentaire a mis en évidence le caractère instantané de l’effet de la prise en charge et une seconde a confirmé l’impact positif du coussin dans une population présentant des troubles de l’attention. Enfin, la quatrième section comporte deux études réalisées au sein du Laboratoire d’Analyse du Mouvement Humain : une analyse biomécanique de la position assise a précisé l’effet positif et immédiat du coussin dynamique et une évaluation du contrôle moteur lombaire a démontré une meilleure proprioception lombaire chez les enfants habitués à utiliser le coussin. En conclusion, bien que cette recherche ne porte que sur une partie des facteurs entrant en ligne de compte pour le bien-être des élèves en classe ainsi que pour leur réussite scolaire, les différentes analyses et perspectives développées tout au long de cette thèse suggèrent la pertinence d’un coussin dynamique dans la mise en place de campagnes posturales préventives. [less ▲]

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See detailOrganocobalt complexes as sources of radicals for macromolecular engineering
Demarteau, Jérémy ULiege

Doctoral thesis (2017)

Organocobalt(III) complexes (R-Co) have an excellent propensity to produce carboncentered radicals by the cleavage of their C-Co bond under mild conditions and, thereby, proved their huge interest in both ... [more ▼]

Organocobalt(III) complexes (R-Co) have an excellent propensity to produce carboncentered radicals by the cleavage of their C-Co bond under mild conditions and, thereby, proved their huge interest in both organic and polymer chemistries. In particular, the cobalt mediated radical polymerization (CMRP) demonstrated its ability to control the polymerization of various monomers, especially the challenging less-activated monomers (LAMs) like vinyl esters or vinyl amides, and to produce the corresponding well-defined (co)polymers. In spite of these progresses, huge challenges are still pending in the controlled synthesis of functional LAMs-containing polymers, particularly those based on ethylene or a-olefins.The present thesis aims to address these challenges and develop a CMRP platform using novel bisacetylacetonato alkylcobalt(III) (R-Co(acac)2) as initiators for the controlled synthesis of α-olefin based (co)polymers by including functional ones. First, well-defined ethylene/vinyl acetate (EVA) copolymers are prepared using a previously reported nonfunctional oligopoly( vinyl acetate)-Co(acac)2 but also from a novel halomethyl-cobalt(III) (XCH2-Co(acac)2) paving the way to the corresponding functional EVAs. This end-chain functionalization route is notably exploited for the design of novel telechelic EVAs and unprecedented ethylenecontaining macrocycles. Finally, the cobalt-mediated radical (co)polymerization of α-olefins having perfluorinated side chains is considered in order to produce innovative well-defined fluorinated polymer structures with various compositions and architectures. Overall, this work aspires to increase the understanding and broaden the scope of the CMRP of LAMs, in particular of α-olefins. [less ▲]

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See detailLa spatialité de la gouvernance des régions urbaines intermédiaires en Europe
Breuer, Christophe ULiege

Doctoral thesis (2017)

The governance of urban regions is a central research topic of urban sciences, and a major challenge for urban actors. In this research, we contribute to the analysis of governance processes by studying ... [more ▼]

The governance of urban regions is a central research topic of urban sciences, and a major challenge for urban actors. In this research, we contribute to the analysis of governance processes by studying the transformation of its spatiality in intermediate European urban regions. Our research postulates the intrinsically spatial nature of urban governance, and is based on three hypotheses: (1) the territorial characteristics of urban regions relate to local politico-administrative fragmentation, (2) the characteristics of politico-administrative fragmentation relate to the construction of a governance scale for urban regions, and (3) governance structures at the level of urban regions relate to territorial characteristics. In order to test these hypotheses, we conducted a research in three complementary parts. The first part is devolted to the state of the art on governance, territorial rescaling and institutional change. The second part analyses quantitatively the politico-administrative fragmentation of 123 intermediate European urban regions, and its links with territorial indicators. The third part analyses qualitatively the processes of transformation of spatial governance in the urban regions of Saint-Étienne (France), Metz (France), Sheffield (United Kingdom) and Liège (Belgium). This complementary research confirms the existence of links between the different aspects of spatiality in the governance of intermediate urban regions in Europe, and concludes that the recomposition processes are intrinsically spatial, territorial and multiscalar. [less ▲]

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See detailContribution à l'enseignement de la traduction au Niger : le renforcement du français langue cible dans la formation des futurs traducteurs.
Amadou Gazali, Alkassoum ULiege

Doctoral thesis (2017)

Teaching translation is a very old activity. While it often used to be performed in the context of language learning, it has changed fundamentally over the past few decades, i.e. since the ... [more ▼]

Teaching translation is a very old activity. While it often used to be performed in the context of language learning, it has changed fundamentally over the past few decades, i.e. since the institutionalization of translation as an autonomous scientific discipline with specific objects and methods. Now, it covers not only linguistics but also other fields including the operating aspect of knowledge and has undergone more methodological transformations over half a century than it did since the Middle-Age, or even since Cicero. In Niger, however, the situation has not yet changed. Teaching translation has remained part of language learning. In this context, the learners’ translation competence is directly associated to linguistic competence. But the latter is far from satisfactory for quite a lot of Niger students, whatever their field of study. In fact, several studies confirmed the poor performance of Niger students in relation to mastery of their working language, French. Indeed, despite its exclusive status as the language of administration and education, French is not mastered enough to be used as a basis for the learning of another language and even less for translation purposes. This is why this study is based on the hypothesis according to which improving the target language in translator training would largely contribute to upgrade their translation competence. It therefore aims to enhance Niger prospective translators’ translation competence by improving their knowledge of the working language. To this end, an experimental research method is used that relies on a classical type scheme involving pre- and post-experimentation observations. An experimental treatment is applied between the two observation stages, which consists of language remedial courses. The verification of the hypothesis depends on operational aspects of the study as well as on the results yielded by the interpreting of collected data. [less ▲]

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See detailImpact of Murid Herpesvirus 4 Imprinting against Heterologous Respiratory Immunopathologies
Dourcy, Mickael ULiege

Doctoral thesis (2017)

Gammaherpesvirus (ɣ-HVs) infections are highly prevalent in both human and animals. They persist in their host by establishing and maintaining latent infections. Murid herpesvirus 4 (MuHV-4) is a wild ... [more ▼]

Gammaherpesvirus (ɣ-HVs) infections are highly prevalent in both human and animals. They persist in their host by establishing and maintaining latent infections. Murid herpesvirus 4 (MuHV-4) is a wild rodent pathogen that can be used as a model of ɣ-HV infection in the laboratory mouse. Like other ɣ-HVs, MuHV-4 profoundly imprints the host immune system to allow completion of its biological cycle. In particular, MuHV-4-induced modulations have been shown to confer bystander protection against heterologous secondary infections. Type 2 respiratory immunopathologies are of major interest in public health, specifically in developped countries. Notably, allergic asthma affects more than 300 million people worldwide and hSRV (human respiratory syncytial virus) inactivated vaccine-induced Th2 immunopathology substantially delays the development of vaccines against this virus which is yet the main infectious agent of bronchopneumopathies in children and olders. According to the hygiene hypothesis, epidemiological studies suggest that late primoinfections to human ɣ-HVs are correlated to an increased risk of allergic sensitization later in life. Using the MuHV-4 model, the in vivo impact of a ɣ-HV infection was tested against the development of on one hand, allergic airway inflammation induced by house dust mites (HDM) allergens (study 1) and on the other hand, anti-pneumovirus Th2 immunopathology, using Pneumonia virus of mice (PVM) to faithfully mimic the original hRSV disease in homologous host-virus model (study 2). Our results have shown that MuHV-4-infected mice are protected from the development of both allergic and vaccine-induced type 2 immune disorders. Moreover, MuHV-4-infected mice were also clinically protected from the subsequent heterologous infection with PVM. Finally, the protective mechanism against HDM allergic asthma was deciphered; pulmonary MuHV-4 lytic infection causes the severe depletion of the alveolar niche which is repopulated by bone marrow-derived monocytes. These latter cells then differentiate into alveolar macrophages (AMs) that are both phenotypically and functionally distinct from resident AMs. Indeed, in previously MuHV-4 infected mice, these monocyte-derived AMs express regulatory functions to block the activation of dendritic cells involved in allergic sensitization, therefore, conferring protection against allergic airway inflammation. In conclusion, the present thesis has unambiguously unraveled that ɣ-HV infection can protect the host against the development of main public health-related respiratory type 2 immune disorders. Replacement of embryonic AMs by regulatory monocytes is thus a major feature underlying the long-term training of the lung immunity after infections, and could provide a possible mechanistic explanation for the hygiene hypothesis. Altogether, this work opens interesting perspectives for the prevention of respiratory type 2 immunopathologies. [less ▲]

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See detailReal-time Corrective Control in Active Distribution Networks
Soleimani Bidgoli, Hamid ULiege

Doctoral thesis (2017)

The continuous growth of renewable energy injected into Medium-Voltage (MV) distribution systems is expected to create new operational problem such as over- and under-voltages and/or thermal overloads of ... [more ▼]

The continuous growth of renewable energy injected into Medium-Voltage (MV) distribution systems is expected to create new operational problem such as over- and under-voltages and/or thermal overloads of equipment. Therefore, the need for real-time corrective control will go increasing, since reinforcing the network to deal with these temporary situations is seldom an economically viable option for the Distribution System Operator (DSO). This requires monitoring the system through an appropriate measurement and communication infrastructure and taking control actions if the system is going to exceed its prescribed operational limits. In this thesis, number of methods and algorithms have been devised, developed and tested which can allow DSOs to enhance the real-time monitoring and control of their grids, taking into account various practical challenges. The main components taking part in these corrective actions are Dispersed Generation Units and the transformer Load Tap Changer in the main sub-station. A centralized control architecture is chosen mainly for its capability of coordinating multiple control actions. Furthermore, the scheme is extended to a two-level structure in order to combine a fast but partial correction by the local controllers, followed by the smooth, coordinated control of the centralized one. Another extension deals with enabling the controller to contribute to LV network voltage corrections by adjusting voltages on the MV side of the MV/LV transformers where a voltage problem has been detected. Finally, the time frame of the centralized controller is extended with preventive security restoration. The latter uses near-future production/consumption predictions to determine if the active distribution network is going to operate within prescribed limits and, if not, to determine appropriate preventive decisions that can be used, for instance, as reference for the real-time corrective controller. [less ▲]

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See detailBovine brucellosis in Argentina: current situation and intraherd simulation model
Aznar, Maria Natalia ULiege

Doctoral thesis (2017)

Bovine brucellosis is an infectious disease, which can negatively affect cattle productivity and human health. It is endemic in Argentina, where 0.8% of cattle and 12% of farms are infected, having this ... [more ▼]

Bovine brucellosis is an infectious disease, which can negatively affect cattle productivity and human health. It is endemic in Argentina, where 0.8% of cattle and 12% of farms are infected, having this percentages remained stable throughout the years. This thesis studies the disease in the country. At first a review on the Argentine situation is presented, which leads to two remarkable aspects: brucellosis remains endemic and it is not possible to reach its eradication. In order to to clarify those points, four main studies were performed. The study 1 is an analysis of cattle movement that showed that there are some districts potential spreaders of the disease while others have more at risk of introduction. The study 2 constitutes an estimation of the brucellosis prevalence and identification of the risk factors associated with an increased occurrence, which helps to improve the knowledge of the epidemiology of the disease in the country. When assessing the situation at the provinces under study, a spatial cluster of infected farms was detected. In that region, farms are considerably large, having lowanimal densities and few movements. Those factors probably correlate with infrequent veterinary control and poor sanitary conditions of the herds. Special attention should be paid to those zones sharing these characteristics since there is high chance of finding clusters of the disease. In the study 3 a method for evaluating some farmers' and veterinarians' management practices in relation to brucellosis and for assessing the vaccination campaign and coverage is developed. It shows that the vaccination campaign is globally well implemented, but the immunization coverage and some management practices should be improved. Finally, the study 4 develops an intra herd simulation model. Its aim is to predict the effects of the disease and to test different control and eradication strategies in different situations. As brucellosis is a contagious disease, when introducing one infected animal in a free herd, it might become endemic. In the case of endemic farms that do not eliminate the reactors, all the tested vaccination strategies produce a reduction in the disease outputs (abortions, infectious deliveries, new infected and born infected) whereas when no vaccination is applied, the outputs remain stable. The isolation of heifers from the general herd reduces the disease outputs by a half. Despite it, if the reactors are not eliminated the sources of infection are kept in the herd. Therefore, a strategy of elimination of infected animals has to be applied. Independently from the chosen vaccination strategy, applying serological tests of high sensitivity and specificity with immediate elimination of reactors produces a dramatic reduction in the disease prevalence. These results might explain the fact that the disease keeps on being endemic in Argentina. Since for achieving eradication at country level, other measures additional to vaccination have to be applied, the mandatory elimination of infected cattle could be taken into account. Summarizing all these issues, it can be concluded that, although there are good regulations to control and eradicate bovine brucellosis in Argentina. The prevalence is not so high and stable throughout the years and, some improvements have to be made in order to achieve eradication. This thesis attempted to assess the Argentine current situation and to provide tools for policy makers and farmers to obtain that goal.   [less ▲]

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See detailLa construction d'un futur sur quatre roues. Une ethnographie du handicap locomoteur dans Mitchell's Plain (Afrique du Sud)
Schnitzler, Marie ULiege

Doctoral thesis (2017)

This thesis explores subjectivities shaped by locomotive disability in the post-apartheid city through an ethnography of ordinary life. Locomotive disability encompasses every limitation of mobility due ... [more ▼]

This thesis explores subjectivities shaped by locomotive disability in the post-apartheid city through an ethnography of ordinary life. Locomotive disability encompasses every limitation of mobility due to an infirmity of the lower limbs. In my discussion, it is conceived as a ‘test’ (épreuve), namely an event that interrupts everyday routines and creates tensions between the responsibilities of different actors’ – people with disabilities, families, the state, etc. These tensions are articulated on various levels. In my discussion, I focus on three of them: the political field that determines a certain type of citizenship, the social networks that constitute the person, and finally the understanding people with disabilities have of their personal history. These levels combine to shape people’s subjectivity, and are analysed in a Foucauldian perspective not just as individuals’ relations with themselves, but also with others and the wider world. [less ▲]

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See detailAdvanced emulsion-templated porous polymers through controlled radical polymerization
Mathieu, Kevin ULiege

Doctoral thesis (2017)

Macroporous polymer monoliths are remarkable materials used in several applications such as supported catalysis, chromatography, water purification, gas capture, to name but a few. The emulsion-templated ... [more ▼]

Macroporous polymer monoliths are remarkable materials used in several applications such as supported catalysis, chromatography, water purification, gas capture, to name but a few. The emulsion-templated polymerization method, often based on conventional radical polymerization, is a very popular and straightforward approach for preparing such porous polymers. Nevertheless, the demand for more and more sophisticated porous supports with controlled porosity, good mechanical properties and specific surface properties, is increasing and requires the development of innovative synthesis strategies. The present thesis aims to explore the possible benefits of controlled radical polymerization (CRP) for the design of advanced macroporous monoliths via emulsion templated polymerization. In a general approach, copolymers with precise architecture, composition and chain-end functionality, were synthesized by CRP and used as macromolecular surfactants for stabilizing various types of high and medium internal phase emulsion polymerizations. A clear effect of the nature and concentration of the surfactants on the porous structures was emphasized. The physical and chemical anchoring of the macromolecular surfactants at the surface of the porous monoliths was also achieved allowing the functionalization of porous supports while preserving their openness. Finally, specific surfactants were designed by CRP for stabilizing CO2-in-ionic liquid (IL) emulsions which paved the way to the single step synthesis of unique and valuable macroporous poly(ionic liquid)s/ILs gels. Overall, the present work highlights the great potential of CRP for the emulsion-templated polymerization and the production of advanced functional macroporous monoliths. [less ▲]

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See detailThe virion transmembrane proteome: a glance to the evolution and to the biology of Cyprinid herpesvirus 3
Vancsok, Catherine ULiege

Doctoral thesis (2017)

Cyprinid herpesvirus 3 (CyHV-3) is the etiological agent of a highly contagious and lethal disease affecting koi and common carp worldwide. Beyond its economic importance, this virus turned out to be an ... [more ▼]

Cyprinid herpesvirus 3 (CyHV-3) is the etiological agent of a highly contagious and lethal disease affecting koi and common carp worldwide. Beyond its economic importance, this virus turned out to be an interesting subject for fundamental research and is currently considered as the archetype of Alloherpesviridae. The divergence of this family with the Herpesviridae is ancestral, with almost no significant homology between CyHV 3 genes and those of Herpesviridae. Consequently, the extensive knowledge acquired for the latter cannot be used to predict CyHV 3 biological features. Virion transmembrane proteins (VTPs) are well documented in Herpesviridae for their involvement in crucial processes such as entry, immune evasion, morphogenesis and egress of progeny virions from the host cells. In contrast, very little is known about the functions of these proteins in CyHV 3 or in any of the alloherpesviruses. The main objective of this thesis was to provide a first functional characterization of CyHV-3 virion transmembrane proteome. The experimental work performed is summarized in two main chapters. The first study aimed to update the list of known CyHV-3 VTPs and to determine those that are essential to viral growth in vitro. Using mass spectrometry approaches and mutagenesis experiments, we identified 16 VTPs in the CyHV-3 FL strain, among which 8 turned out to be essential to viral growth in vitro. The non-essential VTPs were further assessed quantitatively for their relative importance in vitro and in vivo. ORF25, ORF64, ORF108, ORF132, ORF136, ORF148, and ORF149 were shown to affect viral growth in vitro; while the lack of ORF148 or ORF25 caused attenuation to a minor or major extent in vivo, respectively. Finally, we showed that a mutant lacking ORF25 was highly attenuated but induced a moderate immune protection under the conditions tested. Bioinformatic analyses suggested that CyHV-3 ORF27 encodes a VTP. However, no protein corresponding to this ORF was detected in our proteomic analyses. Analyses of genome sequence and protein expression demonstrate that the FL strain, like several other laboratory strains, do not express ORF27 due to presence of various mutations, while it encodes a VTP in field strains. These observation led us to hypothesize that the deletion of ORF27 could confer a selective advantage to viral growth in vitro, while the expression of a functional pORF27 could confer a selective advantage in vivo. These hypotheses were addressed by producing recombinant viruses. In vitro, the CyHV 3 strain lacking ORF27 expression was shown to have a replicative advantage, especially during co-infection with a viral strain expressing this protein. In contrast, in vivo, no difference between both genotypes could be detected in the experimental conditions tested. This observation suggests that the biological functions of ORF27 cannot be revealed in the laboratory conditions used. In conclusion, this thesis provides a first functional characterization of the virion transmembrane proteome of CyHV-3. It represents a firm basis for further research on alloherpesvirus VTPs. [less ▲]

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See detailTowards a system of concepts for Family Medicine. Multilingual indexing in General Practice/ Family Medicine in the era of Semantic Web
Jamoulle, Marc ULiege

Doctoral thesis (2017)

UNIVERSITY OF LIÈGE, BELGIUM Executive Summary Faculty of Medicine Département Universitaire de Médecine Générale. Unité de recherche Soins Primaires et Santé Doctor in biomedical sciences Towards a ... [more ▼]

UNIVERSITY OF LIÈGE, BELGIUM Executive Summary Faculty of Medicine Département Universitaire de Médecine Générale. Unité de recherche Soins Primaires et Santé Doctor in biomedical sciences Towards a system of concepts for Family Medicine. Multilingual indexing in General Practice/ Family Medicine in the era of SemanticWeb by Dr. Marc JAMOULLE Introduction This thesis is about giving visibility to the often overlooked work of family physicians and consequently, is about grey literature in General Practice and Family Medicine (GP/FM). It often seems that conference organizers do not think of GP/FM as a knowledge-producing discipline that deserves active dissemination. A conference is organized, but not much is done with the knowledge shared at these meetings. In turn, the knowledge cannot be reused or reapplied. This these is also about indexing. To find knowledge back, indexing is mandatory. We must prepare tools that will automatically index the thousands of abstracts that family doctors produce each year in various languages. And finally this work is about semantics1. It is an introduction to health terminologies, ontologies, semantic data, and linked open data. All are expressions of the next step: Semantic Web for health care data. Concepts, units of thought expressed by terms, will be our target and must have the ability to be expressed in multiple languages. In turn, three areas of knowledge are at stake in this study: (i) Family Medicine as a pillar of primary health care, (ii) computational linguistics, and (iii) health information systems. Aim • To identify knowledge produced by General practitioners (GPs) by improving annotation of grey literature in Primary Health Care • To propose an experimental indexing system, acting as draft for a standardized table of content of GP/GM • To improve the searchability of repositories for grey literature in GP/GM. 1For specific terms, see the Glossary page 257 x Methods The first step aimed to design the taxonomy by identifying relevant concepts in a compiled corpus of GP/FM texts. We have studied the concepts identified in nearly two thousand communications of GPs during conferences. The relevant concepts belong to the fields that are focusing on GP/FM activities (e.g. teaching, ethics, management or environmental hazard issues). The second step was the development of an on-line, multilingual, terminological resource for each category of the resulting taxonomy, named Q-Codes. We have designed this terminology in the form of a lightweight ontology, accessible on-line for readers and ready for use by computers of the semantic web. It is also fit for the Linked Open Data universe. Results We propose 182 Q-Codes in an on-line multilingual database (10 languages) (www.hetop.eu/Q) acting each as a filter for Medline. Q-Codes are also available under the form of Unique Resource Identifiers (URIs) and are exportable in Web Ontology Language (OWL). The International Classification of Primary Care (ICPC) is linked to Q-Codes in order to form the Core Content Classification in General Practice/Family Medicine (3CGP). So far, 3CGP is in use by humans in pedagogy, in bibliographic studies, in indexing congresses, master theses and other forms of grey literature in GP/FM. Use by computers is experimented in automatic classifiers, annotators and natural language processing. Discussion To the best of our knowledge, this is the first attempt to expand the ICPC coding system with an extension for family physician contextual issues, thus covering non-clinical content of practice. It remains to be proven that our proposed terminology will help in dealing with more complex systems, such as MeSH, to support information storage and retrieval activities. However, this exercise is proposed as a first step in the creation of an ontology of GP/FM and as an opening to the complex world of Semantic Web technologies. Conclusion We expect that the creation of this terminological resource for indexing abstracts and for facilitating Medline searches for general practitioners, researchers and students in medicine will reduce loss of knowledge in the domain of GP/FM. In addition, through better indexing of the grey literature (congress abstracts, master’s and doctoral theses), we hope to enhance the accessibility of research results and give visibility to the invisible work of family physicians. [less ▲]

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See detailEffect of grinding chemistry on the sulphidisation and flotation performances of transitional oxide-sulphide copper ore
Jacques, Simon ULiege

Doctoral thesis (2017)

The influence of pulp chemistry on the flotation performance of sulphide ores has been widely studied. It is well recognised that shifting from a reductive to an oxidative grinding environment affects the ... [more ▼]

The influence of pulp chemistry on the flotation performance of sulphide ores has been widely studied. It is well recognised that shifting from a reductive to an oxidative grinding environment affects the pulp chemistry and improves the flotation performances of sulphide ores. Today numerous operations use high chrome media in their communion circuits for this purpose. However, the role of pulp chemistry on the flotation response of mixed ore is poorly understood. Mixed ore consists of a variety of sulphide and oxide minerals, and forms a part of the supergene enrichment zone of sulphide ore bodies. This study highlights the importance of pulp chemistry for mixed ore recovered by sulphidisation and flotation. [less ▲]

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See detailLa Celestina, un mito literario hispánico (1822-2014)
Francois, Jeromine ULiege

Doctoral thesis (2017)

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See detailAléa climatique et débits des cours d’eau dans le bassin transnational de la Meuse : Co-variabilité, changements possibles et impact sur les débordements
Grelier, Benjamin ULiege

Doctoral thesis (2017)

Climate change is a global socio-environmental concern which required adaptation from human societies in order to compensate negative effects and to take benefit from positive effects. Our research is ... [more ▼]

Climate change is a global socio-environmental concern which required adaptation from human societies in order to compensate negative effects and to take benefit from positive effects. Our research is studying water cycle at the catchment scale and contribute to the adaptation of the transnational Meuse basin to the effects of climate change on hydrological extremes (floods and low flows). To this aim, we adopted a hazard-centered approach. A top-down modelling chain has been set up on two contrasted sub-basins of the Meuse river: the Meuse river at Saint-Mihiel (2543 km², France) and the Ourthe river at Tabreux (1607 km², Belgium). The climate forcing of the chain is constructed on a temporal continuum ranging from the Maunder Minimum (≈ 1650 A.D.) to the end of the 21st century. For the future, climate data are provided by an ensemble of GCMs run in the framework of the Coupled Model Intercomparison Project Phase 5 (CMIP5) and forced with RCP radiative scenarios. For the historical period, gridded data available in the study area are used. Blending past and future climate data is obtained through a transfer function, linking the pressure gradient force to climate forcing variables of catchment streamflow (i.e. atmospheric water and energy supplies). Aggregation of climate data provides a first estimation of potential climatic variability for the two studied sub-basins. The hydrological effect of this potential climatic variability is evaluated in two ways: i) through a regression climate-streamflow transfer function which predicts the streamflow at the outlet of a catchment with the information provided by the pressure gradient force. Regression models are fitted in present climate conditions and used further to extrapolate the streamflow at the outlet of a catchment with CMIP5 GCMs data; ii) through the link between the pressure gradient force and climate forcing variables of streamflow. Regression models are efficient enough to provide robust estimation of the potential climate variability at the scale of interest. The delta-change approach is then applied to potential climate variability to get representative climate scenarios at a daily time step relevant for rainfall-runoff modelling. The tested rainfall-runoff model (GR4J) is calibrated through a climatically robust method. This step gives a first estimation of the two sub-basins sensibility to prescribed climate changes. In order to evaluate the effect of climate change on hydraulic behavior of a river, the modelling chain has been completed with the WOLF1D hydraulic model. Is has been parameterized and validated for a section of the Ourthe river. Boundary conditions were forced with representative climate scenarios to evaluate the climate change effect on overflowing. In a first step, the latter is characterized through overflowing sequences determined through simulated water levels. Then, to overcome the limits of the WOLF1D model in flood-prone area, the flow-duration-frequency behavior of the first overflowing streamflow is studied to show the overflowing evolution under climate change. In the end, our work provides an original framework for studying climate change effect on hydrological extremes through a sampling of climate changes with past and future climate series. The use of a hazard-centered modelling chain is a first step toward adaptation strategies suited for contrasted climate conditions. This contributes in turn to make catchment more resilient. [less ▲]

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See detailModel Order Reduction: Application to Electromagnetic Problems
Paquay, Yannick ULiege

Doctoral thesis (2017)

With the increase in computational resources, numerical modeling has grown expo- nentially these last two decades. From structural analysis to combustion modeling and electromagnetics, discretization ... [more ▼]

With the increase in computational resources, numerical modeling has grown expo- nentially these last two decades. From structural analysis to combustion modeling and electromagnetics, discretization methods–in particular the finite element method–have had a tremendous impact. Their main advantage consists in a correct representation of dynamical and nonlinear behaviors by solving equations at local scale, however the spatial discretization inherent to such approaches is also its main drawback. In- deed, it usually leads to (very) large systems of equations—requiring abundance of computational resources, usually far too much for quasi-real time simulations. In this dissertation, model order reduction of numerical models from finite element discretization is analyzed to efficiently and accurately downsize the number of degrees of freedom in static and dynamic, linear and nonlinear electromagnetic applications. In particular, an in-depth review of state of the art model order reduction methods is performed in view of the aforementioned problems. To this end, the proper orthogonal decomposition is considered to limit the number of unknowns in the resolution process. Nonlinear sampling methods such as: the missing point estimation approach and discrete empirical interpolation method, are compared to reduce the assembly phase. The parametric dependencies are taken into account by resorting to global reduced basis and nonlinear interpolation on manifolds techniques. Finally, a novel decoupled approach for the reduction of a coupled nonlinear magnetodynamic three-phase energy converter with external electric circuits is proposed and analyzed by combining all the aforementioned methods—impressively reducing the computational cost by 95%. This dissertation is genuinely geared towards the application of a priori known meth- ods on a variety of different numerical models of electromagnetic devices. Additional automatic algorithms which eliminate the arbitrary choices of numerical reduction parameters are proposed and compared to reference methods proposed in the litera- ture. The following applications have been considered: a 2D inductor-core system to first illustrate and provide understanding of the proposed methods, a 2D single phase transformer, a 2D three-phase transformer and a 3D microwave antenna. [less ▲]

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See detailCaractérisation multiéchelle du loess de Hesbaye (Belgique) par une approche couplée géologique et géotechnique
Delvoie, Simon ULiege

Doctoral thesis (2017)

A thorough analysis is performed on aeolian silt (loess) deposits. The study is based on an original approach combining geological aspects with physical and mechanical properties of the material. This ... [more ▼]

A thorough analysis is performed on aeolian silt (loess) deposits. The study is based on an original approach combining geological aspects with physical and mechanical properties of the material. This approach is realized by means of a multiscale experimental analysis in which cone penetration test plays a key role. The approach is applied to the study of loess deposits located in the Hesbaye region (Belgium), in which the site of the Romont quarry (Eben-Emael, Belgium) is the subject of a more comprehensive and a more detailed study. About the stratigraphic aspects, a continuous geological cross-section performed along a 18 km long section of the high-speed railway between Liège and Waremme, underlines the variability of the thickness of the loess layer which can locally reach 20 m. The loess sequence is further investigated in three Hesbayan sites (Remicourt, Romont and Rocourt) with cone penetration test (CPT) campaign. The analysis of the cone resistance of the CPT reveals it is possible to define four stratigraphic markers within the regional loess sequence: the near surface decarbonation limit, the transition between the Nagelbeek Tongued Horizon and the underlying Hesbayan loess, the Humiferous Complex of Remicourt, and the Whitish horizon of Momalle on top of the Rocourt Pedocomplex. Physical, geochemical and microstructural characteristics determined from laboratory analyses on samples stratigraphically located around the stratigraphic markers, enable a better understanding of the observed variations of the in situ mechanical behaviour. Porosity, volumetric weight and clay content seem to be three major variables in the understanding of the observed variations of cone resistance. A comparative analysis of geomechanical properties has also been conducted either from different data related to CPT or between CPT results and laboratory measurements. This study includes four items: (i) the comparative analysis of measurements achieved by different CPT cone types (M1, M2 and E), clearly indicates the cone type has negligible influence on the measured cone resistance for silty material. (ii) Soil behaviour type charts based on CPT data confirm the relative heterogeneity of the investigated silty material. (iii) The empirical relation between the oedometric modulus and the cone resistance of the CPT, including the α factor depending on the soil type, is verified for the studied silty material. (iv) A semi-empirical approach based on the bearing capacity theory has been developed to estimate mean apparent cohesion and friction angle of the silt. Finally, results of this PhD thesis may be used for specific and original applications: (i) CPT testing seems to be an interesting investigation technique for rescue archaeology in loess context. (ii) Thanks to the in-depth investigation, the Romont site (Belgium) may provide an interesting site wherein sensors or investigation tests related to geomechanical, physical or structural properties of the material may be tested or calibrated into a natural silty medium. (iii) The detailed characterisation of aeolian silt leads to numerous properties related to geomechanical, physical and geochemical aspects of the material. These data may be used in studies dealing with loess deposits. [less ▲]

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See detailTransmission des phytovirus associés aux pucerons: une approche multitrophique
Bosquée, Emilie ULiege

Doctoral thesis (2017)

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See detailEmergent vortex phenomena in spatially and temporally modulated superconducting condensates
Jelic, Zeljko ULiege

Doctoral thesis (2017)

Superconductivity is an electronic state of matter arising from the existence of a common wave function with a coherent phase extending on a truly macroscopic scale. One major manifestation of this ... [more ▼]

Superconductivity is an electronic state of matter arising from the existence of a common wave function with a coherent phase extending on a truly macroscopic scale. One major manifestation of this striking quantum phenomenon is the dissipationless transport of electrical current, an asset deserving particular attention in the present times where the efficient energy distribution has become of utmost importance. Unfortunately, the motion of quantum units of magnetic flux (so-called vortices or fluxons), which is an unavoidable side-effect found in superconductors in the presence of transport currents and magnetic fields, severely limits the conditions to preserve dissipationless transport. This poses a challenge for achieving the functionalization of superconducting materials and threatens their spectrum of applications. It is widely known that any inhomogeneities (either material imperfections, or ones made artificially), which locally suppress superconductivity on the scale comparable to the core of the vortex, can pin the vortex and delay the onset of the vortex motion to higher applied currents. In recent years a substantial effort has been made to minimize the effects of current-induced vortex motion by tailoring arrays of artificial pinning centers. Besides improving the critical parameters of the superconducting state, a pinning matrix can be used for the manipulation of vortex matter, thus directly affecting the vortex dynamics, such as rectification of vortex motion under an ac drive (vortex diode) by introducing asymmetric pinning landscapes. In the literature one can find that the realization of the anchoring of the vortices can be based on nanostructured arrays of perforations, chemically grown defects, permanent nanomagnets, or even pinning sites produced by heavy ion bombardment. All of those realizations are based on a permanent imprint on the superconductor, without any possibility for subsequent modifications in the distribution and strength of the pinning. The principal objective of this thesis is to investigate the dynamical behavior of vortex matter under an entirely new kind of pinning landscape consisting of spatial and temporal modulation of the superconducting condensate. A particular case of spatial modulation is considered in a constricted structure where current lensing can cause extremely high vortex velocities. Subsequently, a time-dependent thermal potential introduced to the superconducting condensate will cause stroboscopic resonances during the vortex motion - a phenomenon that cannot be observed in the systems with static pinning imprints. Finally, a study of electronic gating is presented, where the local properties of superconductor, such as mean free path, or electronic band structure in general, can be influenced electronically. This is a completely unexplored interdisciplinary research topic, which will eventually allow one to manipulate individual vortices in superconducting materials by means of spatially confined and temporally controlled thermal and electromagnetic excitations. Furthermore, such techniques can provide one fundamental insight in different states of the vortex matter with respect to variation of the transport current, highly relevant for understanding the resistive state of superconducting materials and their applications. [less ▲]

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See detailStudy of plant-aphid interactions in Gabonese vegetable crops and biological control perspectives
Bayendi Loudit, Sandrine ULiege

Doctoral thesis (2017)

Periurban agriculture increased vegetables production in the cities. A survey was conducted in three market gardening in Libreville and Owendo cities to register crop and pesticides diversity uses by ... [more ▼]

Periurban agriculture increased vegetables production in the cities. A survey was conducted in three market gardening in Libreville and Owendo cities to register crop and pesticides diversity uses by farmers. The most abundant cultivated species throughout the year appeared to be amaranth (Amaranthus ama L. Amaranthaceae). The most important pests were aphids (Hemiptera: Aphididae) and some beetles (Coleoptera). To control the pests, conventional neurotoxic insecticides were used with effect on environment and human health. In order to identify the occurring insects in the selected areas, a monitoring of insects was carried out during two years on amaranth, roselle, tomato (Lycopersicon esculentum M., Solanaceae) and cabbage (Brassica oleracea L., Brassicaceae). Entomological abundance and diversity were assessed through weekly trapping and visual observations from July to August each year. Insects were collected, identified at the taxonomic level of the family, and classified into three categories: pests, beneficials and associated insects to agriculture. Eighty four families belonging to height orders were recorded with 7910 and 3148 sampled individuals in 2012 and 2013 respectively. The predominant insect families were in both years Aphididae, Cecidomyiidae (Diptera) and Chrysomelidae (Coleoptera) for pests, Dolichopodidae (Diptera), Staphylinidae (Coleoptera) and Coccinellidae (Coleoptera) for beneficials, and Muscidae (Diptera), Psychodidae (Diptera) and Formicidae (Hymenoptera) for associated insects. As aphids are the most important pests, further study at species level and in relation to predatory beneficials were assessed on vegetable crops in 2013 in two periurban gardening sites. The Aphis craccivora Koch aphid was the most abundant aphid species observed infesting amaranth in both sites. The other aphid species were Lipaphis erysimi Kaltenbach, Myzus persicae Sulzer, Aphis fabae Scopoli and Aphis gossypii Glover. Moreover, seven species of natural enemies were trapped, mainly predatory hoverflies (Diptera: Syrphidae) and ladybirds (Coleoptera; Coccinellidae). A. craccivora Koch is known to be a vegetable pest. Its recent identification as pest in amaranth motivated us to study their multitrophic interactions. Since relationships between aphids and host plants could be related to symbiont and feeding behaviour. A. craccivora endosymbiont bacteria and saliva protein diversity were analysed to explain plant–aphid interactions. Indeed, Buchnera aphidicola was found. Some proteins were only identified in solid and soluble saliva, while others originated from Serratia sp. endosymbiont. Two of the identified proteins are involved in plant-pathogen interactions: calmodulin and elongation factor Tu. To control A. craccivora which causes several crop damages, volatile organic compounds (VOC) have been studied. Only aphid alarm pheromone (E)-β-farnesene (EβF) was identified and quantified. Its effect on escape behaviour in aphids has been demonstrated on three species. A. craccivora responded more strongly than the two other Aphidinae (M. persicae and A. fabae) species with 78% of the individuals initiated dispersal behavior at 500 ng dose of EβF. In another laboratory study, the repellency effect of (E)-β-farnesene, methyl salicylate and two essential oils of basil species (Ocimum gratissimum L. and Ocimum basilicum L. Lamiaceae) were determined, while no repellent effect was observed. Also, aphid populations were reduced by exposure to EβF and O. gratissimum essential oil. This study is one of the few to explore the description of insects in the market gardens of Libreville. This could contribute to the elaboration of the sustainable development strategies of pest control in the zones. [less ▲]

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See detailNew therapeutic approaches for malignant pleural mesothelioma targeting DNA repair and transforming growth factor TGF-alpha
Staumont, Bernard ULiege

Doctoral thesis (2017)

Malignant pleural mesothelioma (MPM) is an aggressive cancer of the pleura mainly caused by asbestos fibers exposure. MPM is notably characterized by a very poor prognosis and current treatments ... [more ▼]

Malignant pleural mesothelioma (MPM) is an aggressive cancer of the pleura mainly caused by asbestos fibers exposure. MPM is notably characterized by a very poor prognosis and current treatments, including radiation and chemotherapy, are unsatisfactory. As genomic analyzes show that the major mutations occurring in MPM cells pertain to checkpoint control and DNA repair, a first part of this thesis addresses the DNA damage response and the mechanisms of DNA repair in several MPM cell lines. In this study, we show that gamma ionizing radiation (IR) induces cell cycle arrest of MPM cells at the G2-M checkpoint. We also demonstrate that MPM cells are driven prematurely towards mitosis following the abrogation of IR-induced G2 arrest by the checkpoint inhibitor UCN-01, however without a significant induction of cell death. To avoid excessive genomic instability, DNA repair mechanisms are likely to play a key role in such DNA-damaging conditions. We therefore evaluate here the efficiencies of the two main DNA double-strand break repair mechanisms, non-homologous end-joining (NHEJ) and homologous recombination (HR) and highlight differences in such repair activities among MPM cell lines and in comparison to control mesothelial cells. We underline an efficient HR repair in MPM cells, opening the door to additional investigations that might reveal an addiction to activated DNA repair pathways and thereby render MPM cells hypersensitive to targeted combination therapies. In the second part of this thesis, we perform a pre-clinical study investigating the resistance of MPM to a particular epigenetic-based therapy associating the histone deacetylase (HDAC) inhibitor valproic acid (VPA) and doxorubicin. By comparing MPM cell lines with a differential sensitivity to this combination chemotherapy, this study suggests a correlation between transforming growth factor-alpha (TGF-α) expression and resistance to treatment. We further confirm the role of TGF-α in chemoresistance by modulating its expression in highly- and poorly responsive MPM cell lines. In addition, pharmacological inhibition of TGF-α’s receptor (EGFR or epidermal growth factor receptor) by tyrosine kinase inhibitors gefitinib and erlotinib improves the efficacy of VPA+doxorubicin in vitro. Dual HDAC-EGFR inhibitor CUDC-101 furthermore synergizes with doxorubicin to induce apoptosis in vitro and to slow down tumor growth in two different MPM mouse models, emphasizing its therapeutic potential and opening new prospects for combination therapies associating HDAC and EGFR inhibition against MPM. With two different approaches, this thesis provides a better understanding of MPM resistance to chemo- and radiotherapies and offers clues for new therapeutic strategies based on DNA repair pathways and dual HDAC-EGFR/TGF-α inhibition. [less ▲]

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See detailPLUMAGE DIVERSITY IN BASAL PARAVIANS
Lefevre, Ulysse ULiege

Doctoral thesis (2017)

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See detailIsolation and characterization of nanocelluloses from wheat straw and their application in agricultural water-saving materials
Liu, Qi ULiege

Doctoral thesis (2017)

Humans have been cultivating land for approximately 12,000 years. As such, most countries worldwide have considered crop waste as a global issue linked with environmental protection, economic development ... [more ▼]

Humans have been cultivating land for approximately 12,000 years. As such, most countries worldwide have considered crop waste as a global issue linked with environmental protection, economic development, and healthy living. Many varieties of straw are produced all over China in massive quantities (more than 900 million tons per year). Although banned by the government, stubble burning is widely applied by Chinese farmers as an easy and cheap way to remove stalks after harvests. However, this practice significantly contributes to China’s carbon dioxide emissions and health risks associated with the thick mists it produces. As a renewable biomass resource, straw can be used to make new marketable materials, but its full potential has yet to be realized. Thus, future studies should be directed toward the isolation and rational use of agricultural waste. In addition to the pollution caused by agricultural waste, water shortage, particularly in northern and northwestern China, severely hinders agricultural production. This region accounts for half of the total surface of China but has less than 20% of the total national available water resources. Despite the severity of the water shortage in this region, the efficiency of irrigation water use is only 40%. Many strategies have been applied to promote a water-saving agriculture. One such strategy is the use of water-saving materials, such as plastic mulching films and superabsorbent polymers. However, these two materials are non-biodegradable, and their mechanical properties are unsatisfactory. A systematic analysis of the literature revealed that agricultural waste is a cheap and promising source of raw materials that could be used to obtain cellulose and nanocelluloses. Nanocelluloses can be used for the industrial production of super-strong but lightweight nanocomposite materials. The first step involved the isolation of cellulose, cellulose nanocrystallines (CNCs), and cellulose nanofibers (CNFs) from wheat straw. First, four CNCs were isolated from four commercial microcrystalline celluloses (MCCs) through sulfuric acid hydrolysis. The effects of the characteristics of the MCC on the morphology, structure, and properties of the resulting CNCs were assessed. The results revealed that both particle size and dispersity influenced the isolated CNCs. Second, cellulose was isolated from wheat straw through a microwave-assisted chemical treatment process that reduced chemical use. The reaction conditions and promoting effect of microwave on the resulting fibers were investigated. The results indicated that temperature played the most important role in cellulose isolation, and that microwave can reduce either the reaction time or the chemical use during the microwave-assisted alkali hydrolysis process. High-purity (94%) CNFs were isolated from wheat straw through an environmentally friendly, multi-step treatment process that combined steam explosion, microwave-assisted hydrolysis, and microfluidization. Chemical identification and characterization were performed to study the effect of each treatment step and investigate the potential utilization of CNFs in nanocomposites. Chemical analysis showed that the cellulose content increased from 44.81% to 94.23%, whereas the hemicellulose and lignin contents significantly decreased from 33.41% and 8.75% to 5.54% and 1.68%, respectively. Long and loose 10–40 nm wide nanofiber bundles and an entangled network of cellulose fibers with an average individual diameter of 5.42 nm were observed during this eco-friendly process. In the last part of this study, nanocelluloses were introduced into superabsorbent polymers and mulching films used in agriculture to improve their performance. The effects of nanocelluloses on their structure, properties, and mechanical performance were investigated. First, superabsorbent polymers of acrylamide–acrylate copolymers and others with CNFs, CNCs, or MCC were synthesized. The swelling capacities in pure water and in various solutions, the capacities for repeated water absorption, the water-retaining capacities in soil, and the mechanical properties of the hydrogels were compared. The results revealed that the 3D structures of the acrylamide–acrylate–CNF and acrylamide–acrylate–CNC hydrogels were strengthened by the nanocellulose. These two polymers exhibited excellent capacities for repeated water absorption. By contrast, the biodegradable agricultural mulching film did not present satisfying mechanical and barrier properties as an alternative for ordinary polyethylene film. In this thesis, CNC was introduced into the film of poly (butyleneadipate-co-terephthalate) /polylactic acid composites. Poly(butyleneadipate-co-terephthalate)/polylactic acid/CNC films with various contents of CNC were prepared, characterized, and tested as for their properties. Compared with the film without CNC, poly (lactic acid) / poly (butylene-adipate-co-terephtalate)/3% CNC film showed an increased deformation by 188.80%. The barrier performance of the films increased with increasing CNC content. However, the tensile properties decreased when the CNC content exceeded 3%. Both the mechanical and barrier properties were promoted. These results highlighted that (i) wheat straw is a cellulose-rich natural resource of CNF and CNC; (ii) microwave can reduce either the reaction time or the chemical use during the cellulose-isolation process; (iii) high-purity CNF could be obtained through an environmentally friendly method; and (iv) nanocellulose could improve the mechanical properties of both superabsorbent polymers and mulching films, and enhance their performances in agricultural applications. In a broader perspective, microwave and other techniques should be further explored in the context of green isolation processes. Agricultural biomass natural fiber-based composites must be further investigated to maximize their applications. Approaches that could offer significant cost savings for the industrial production of nanocellulose and new nanocellulose-based materials should be developed further. We aim to promote the research interest for the isolation and application of agricultural-waste-based nanocellulose, which deserve further research and documentation. This thesis is only the beginning of a greater endeavor. [less ▲]

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See detailHorizontal integration under yardstick competition
Teusch, Jonas ULiege

Doctoral thesis (2017)

Horizontal integration through mergers and cross-ownership is ubiquitous; industries regulated by yardstick competition are no exception in this regard. However, even though yardstick competition is ... [more ▼]

Horizontal integration through mergers and cross-ownership is ubiquitous; industries regulated by yardstick competition are no exception in this regard. However, even though yardstick competition is applied to sectors of vital economic importance, such as energy and water networks, the welfare effects of horizontal integration in these settings have largely escaped scientific scrutiny. The dissertation therefore studies the welfare implications of horizontal integration under yardstick competition and identifies potential trade-offs. Specifically, whereas mergers and cross-ownership may bring about efficiency gains, there is a possibility that horizontal integration simultaneously decreases the effectiveness of regulation, benefiting certain firms at the expense of consumers and competitors. Key conditions for such strategic effects to occur and to dominate efficiency effects are derived in a principal-agent model. The thesis also demonstrates that the issue is not merely of academic interest, but has affected the practical application of yardstick competition in the electricity distribution industries of both Belgium and Norway. Chapter 1 analyses how horizontal mergers, joint ventures and regulatory decentralisation complicate the application of yardstick competition in Belgian electricity distribution. Chapter 2 develops a theoretical model of mergers under yardstick competition - formalising the welfare trade-offs at the heart of this dissertation. Chapter 3 leverages Data Envelopment Analysis to quantify both efficiency and strategic effects of horizontal restructuring in Norwegian electricity distribution and points to a recent merger that appears to have been driven by strategic motivations. Chapter 4 uses several econometric identification strategies - dynamic regression, matching on observables and instrumental variables - to establish that between 2007 and 2015, cross-ownership increased firm performance in Norwegian electricity distribution, which suggests that the net welfare effects were positive in this application. [less ▲]

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See detailIn silico modeling of bone formation under the influence of calcium phosphate-based biomaterials and osteochondrogenic growth factors
Manhas, Varun ULiege

Doctoral thesis (2017)

Bone regeneration is a complex process that involves regulation of different cell types by multiple biochemical, physical and mechanical factors. Unlike other biological tissues, bone can heal scarlessly ... [more ▼]

Bone regeneration is a complex process that involves regulation of different cell types by multiple biochemical, physical and mechanical factors. Unlike other biological tissues, bone can heal scarlessly and recover its original shape, size and strength. However, about 5% of bone defects result in non-unions. To tackle these non-unions, tissue engineering (TE) aims to develop bone substitutes or intelligent TE constructs to replace damaged, diseased or aging tissue. These bone substitutes/TE constructs are designed to support the chemotaxis, proliferation and differentiation of bone progenitor cells as well as being a biochemical agent delivery system. However, these delivery systems have a few limitations such as structural weakness of the carrier, high doses of biochemical agents being delivered due to burst release, unknown optimal concentrations of implanted cells and their high cost. Another drawback of these systems is the limited understanding on the relationship between biochemical agent dose, implanted cells, carrier volume, carrier material type and resultant bone formation. Given their significant medical potential, there is an increasing demand to design and develop improved bone substitutes/TE constructs. This PhD work fits in the long-term vision that mathematical models can be used as a part of design and manufacturing processes to develop improved treatment strategies and ultimately save experimental time and costs. In the first part of this work, a novel computational model was developed to predict the in vitro release of Ca2+ ions from calcium phosphate (CaP)-based scaffolds. The developed model was based on the Noyes-Whitney equation, the Fick’s second law of diffusion equation and the level-set method (LSM). The model was dependent on biophysicochemical phenomena such as dissolution, diffusion and degradation along with specific scaffold characteristics such as composition, size and shape. The predictions of the model were compared to dedicated experimental results. In the second part of this work, we investigated the use of a previously reported oxygen-dependent fracture healing model to elucidate the in vivo bone formation capacity of bone morphogenetic protein-2 (BMP-2) delivery systems in an ectopic environment. Specific attention was paid to the influence of BMP-2 dose and carrier volume on ectopic bone formation. The performance of this mathematical model was corroborated by comparison with experimental results published in the literature. Finally, the model was applied to investigate the influence of different BMP-2 release profiles on ectopic bone formation. In the third part of this work, we developed a novel computational model to predict the CaP and BMP-dependent ectopic bone formation in nude mice with and without incorporation of donor cells. The model specifically investigated the influence of BMP-2 dose, donor cell concentrations and calcium ion release on ectopic bone formation. The performance of this mathematical model was compared to the results of dedicated in-house experiments. The model was able to capture essential elements of the experimental results yet at the same time, a number of points for further improvement were identified. In the final part of this work, we investigated the application of the aforementioned CaP and BMP-dependent bone formation model to an orthotopic setting in sheep. The performance of the mathematical model was corroborated by comparing the model predictions with experimental results published in the literature. Subsequently, the model was applied to investigate the influence of different CaP-BMP-cell combinations on orthotopic bone formation, simulating in-house ongoing experiments. In conclusion, this PhD work illustrates a computational step taken towards enhancing the understanding on the role of CaP and BMPs in healing large bone defects. [less ▲]

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See detailCarte interactomique entre l'oncoprotéine Tax du virus HTLV-1 et les protéines à domaines PDZ.
Blibek, Karim ULiege

Doctoral thesis (2017)

HTLV-1 (Human T-cell Leukemia Virus) is the etiologic agent of human adult T-cell leukemia (ATL) and tropical spastic paraparesis (TSP). More than 20 million people worldwide are infected with the HTLV-1 ... [more ▼]

HTLV-1 (Human T-cell Leukemia Virus) is the etiologic agent of human adult T-cell leukemia (ATL) and tropical spastic paraparesis (TSP). More than 20 million people worldwide are infected with the HTLV-1 virus, but only about 5 % develop the associated pathologies. At present, efforts are invested in the search for treatments that may improve the survival expectancy of patients infected by the HTLV-1 virus. The diagnosis of HTLV-1 infection is hampered by the viral genome latency (up to 40 years) and treatment options are limited. To propose novel therapeutic opportunities, it thus is necessary to better understand the host molecular mechanisms perturbed by the HTLV-1 infection. The HTLV-1 genome encodes for the Tax-1 protein, which confers the transforming ability of the virus. The Tax-1 protein is known as the transactivator factor of the HTLV-1 virus genome expression (TransActivator of pX region). It is also involved in the destabilization of several molecular mechanisms within the host, leading to cellular transformation. Tax-1 protein displays several functional domains and interacts with a wide range of cellular proteins. In particular, the Tax-1 protein sequence contains, at its carboxy-terminal end, a motif of four amino acids able to interact with PDZ domain (PSD95-DLG1-ZO1) containing proteins. It has been demonstrated that deletion of the PDZ binding motif (PBM) of the Tax-1 protein leads to a decrease of its oncogenic capacity in vitro. Cellular proteins containing PDZ domains are involved in the formation of cellular junctions, synapses and in cellular receptors assembly. Some of PDZ proteins are capable of relaying extracellular signals and participate in the control of proliferation. The human genome codes for at least 150 proteins with PDZ domains. However, the specificity of the oncoprotein Tax-1 to target these proteins remains unknown. In this study, we have mapped The Tax-1 - PDZ interactome using a combination of several methods. We reveal that Tax-1 selectively target a number of PDZ domains-containing proteins potentially involved in HTLV-1 pathogenesis. We validated our approach by focusing on the role of SDCBP and LNX2 proteins in HTLV-1 biology. Our work also demonstrated that the Tax-1-PDZ interactome might represent an attractive therapeutic target for HTLV-1-induced diseases. [less ▲]

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See detailCaractérisation ontogénique, phénotypique et fonctionnelle des macrophages interstitiels pulmonaires après exposition à des composés bactériens
Sabatel, Catherine ULiege

Doctoral thesis (2017)

Respiratory mucosal surfaces are continuously exposed to harmless antigens and immunostimulatory molecules of microbial origin. According to the « self/non self » and « danger » theories, this should ... [more ▼]

Respiratory mucosal surfaces are continuously exposed to harmless antigens and immunostimulatory molecules of microbial origin. According to the « self/non self » and « danger » theories, this should normally result in the developpment of unwanted immune responses towards these inhaled antigens such as Th2-mediated allergic responses. This is however not the case in most people. The hygiene hypothesis postulates that living in an environment rich in microbial components paradoxically protects from airway allergy, implying the existence in the lung of suppressive mechanisms triggered by these immunogenic signals. In this study, we showed that synthetic bacterial DNA rich in unmethylated CpG motifs (CpG) has the unique ability to significantly increase the population of lung interstitial regulatory macrophages (IM) from CCR2-independent monocytes residing in the lung or mobilized from the spleen. Moreover these CpG-induced IM demonstrated a hypersuppressive profile as they produced more IL-10 than their steady state counterparts. Using mice models of airway allergy we showed that the transfert of IM isolated from CpG-treated mice recapitulated the protective effects of CpG when administered before allergen sensitization or challenge. This IM-mediated protection was dependant from IL-10 as CpG-induced Il10-/- IM had no protective effect. The expansion of pulmonary regulatory IM from CCR2-independent pulmonary and splenic monocytes upon CpG exposure could be a possible mechanism by which exposure to an environment rich in microbial products protects against asthma. [less ▲]

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See detailEtude de la transmission du gammaherpèsvirus murin 4: importance de la glycoprotéine gp150 et développement de stratégies antivirales basées sur l'utilisation du cidofovir
Zeippen, Caroline ULiege

Doctoral thesis (2017)

Gammaherpèsviruses are important pathogens in human medicine. Indeed, Epstein Barr virus and Kaposi Sarcoma associated herpesvirus are responsible for numerous lymphoproliferative diseases and cancers ... [more ▼]

Gammaherpèsviruses are important pathogens in human medicine. Indeed, Epstein Barr virus and Kaposi Sarcoma associated herpesvirus are responsible for numerous lymphoproliferative diseases and cancers. Murid Herpesvirus-4 (MuHV-4) is usually used as a model for human gammaherpèsviruses. Until now, the major limitation of this model was the absence of transmission in laboratory animals. Recently, a sexual transmission of MuHV-4 has been described in laboratory mice. This observation allows, on the one hand, to study mechanisms underlying natural transmission, such as cellular trospism, importance of viral proteins, or immunity response during this part of the cycle. On the other hand, this transmission model allows to test efficiency of measures to reduce transmission. Indeed, herpesvirus are archetype of persistant viruses as infection persists lifelong once established. Studying mechanisms underlying transmission and how to use these mechanisms to reduce it efficiently is therefore of primordial importance. In a first study, we focussed on the biological relevance of mechanisms described previously in vitro. Indeed, a MuHV-4 glycoprotein, gp150, has been shown to participate to the release of infectious particles from cells and to evasion of humoral immunity, two functions that could be important for the virus during transmission. Our results showed that gp150 is essential for an efficient sexual transmission of the MuHV-4. Indeed, gp150 promotes the release of infectious particles from infected vaginal epithelial cells. These results has been published in Journal of Virology in July 2017. In a second study, the same model was used to test efficiency of an antiviral molecule to reduce sexual transmission of the MuHV-4. A nucleotide analogue, the cidofovir, was administrated to mice according to different protocols. A daily administration of cidofovir reduced drastically genital shedding, but also prevent completely infection of naive mice after sexual contact. Finally, a single injection of cidofovir, administered 24 hours after sexual contact, reduced significantly transmission. Altogether, in this work, we used a transmission model of a gammaherpèsvirus in two differents studies: the first foccused on glycoprotein implicated during the transmission and established the importance of a single viral glycoprotein for an efficient transmission. The second study highlighted the efficiency of antiviral drugs to prevent infection by gammaherpesviruses. [less ▲]

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See detailTowards a development of iron phosphate-based materials as positive and negative electrodes for Li-ion batteries
Karegeya, Claude ULiege

Doctoral thesis (2017)

The design, synthesis and electrochemical characterization of new electrode materials hold the key for fundamental advances in energy conversion and storage technologies. Polyanionic compounds have been ... [more ▼]

The design, synthesis and electrochemical characterization of new electrode materials hold the key for fundamental advances in energy conversion and storage technologies. Polyanionic compounds have been heavily investigated as possible electrode materials in lithium- and sodium-ion cells. This thesis focused on the design, synthesis, size and morphology tailoring of iron phosphate based electrode materials in order to enhance their electrochemical properties. Four iron phosphate-based electrode materials classified in three groups: Na2Mn1.5Fe1.5(PO4)3, NaxMxFe(3-X)(PO4)3 (X=1.25 when M=Ni and x=1.5 for M= Mn) and Fe1.19(PO4)(OH)0.57(H2O)0.43, were investigated in this work. All these compounds were obtained through wet chemical (hydrothermal or solvothermal) synthesis routes. The preparation protocols and characterization techniques to study the structural, particle size, morphological and electrochemical properties of the above materials have been discussed in the following chapters. Sodium manganese iron phosphate alluaudite structure is one of the studied compounds group. Na2Mn1.5Fe1.5(PO4)3 is obtained via one step hydrothermal synthesis reaction and it was electrochemically studied without any other further heat treatment. NaxMxFe(3-X)(PO4)3 (X=1.25 for M=Ni and x=1.5 for M= Mn) compounds were obtained through solvothermal method in ethylene glycol. Na1.25Ni1.25Fe1.75(PO4)3 is a new material. Both materials have been electrochemically characterized for the first time in this work. Fe1.19(PO4)(OH)0.57(H2O)0.43 was obtained by modifying conventional hydrothermal synthesis of this materials by the addition of conducting carbon (carbon black and carbon nanotubes) in the precursors solution during synthesis that enhance its electrochemical properties as described in this thesis. The Li-ion intercalation reaction mechanisms in Fe1.19(PO4)(OH)0.57(H2O)0.43 cathode material were also investigated by using operando XRD and Mössbauer spectroscopy techniques. The above studies of iron phosphate-based polyanionics as electrode materials in alkali metal-ion batteries show that this group may be the right key in replacing current commercial unsafe electrode materials. The possibility of improving alternative soft chemical synthesis methods to design new materials or improving electrochemical performance of existing electrode materials was also explored here. The roadmap for our current and future work has been proposed, the materials of our future interest have been chosen basing on their promising rich crystal structure and electrochemical properties by comparing them with the studied materials. [less ▲]

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See detailDevelopment of new catalysts for proton exchange membrane fuel cells (PEMFCs)
Zubiaur, Anthony ULiege

Doctoral thesis (2017)

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See detailCharles de Méan, le Papinien liégeois
Lagasse, Benoît ULiege

Doctoral thesis (2017)

La thèse tend à déterminer si Charles de Méan, surnommé le Papinien liégeois, mérite ce surnom signifiant qu'il a été le plus grand jurisconsulte qu'ait connu la principauté de Liège. Pour ce faire, elle ... [more ▼]

La thèse tend à déterminer si Charles de Méan, surnommé le Papinien liégeois, mérite ce surnom signifiant qu'il a été le plus grand jurisconsulte qu'ait connu la principauté de Liège. Pour ce faire, elle tend à étudier une partie de son oeuvre majeure, les Observationes et res judicatae ad jus civile Leodiensium, Romanorum, aliarumque gentium canonicum et feudale. Par ailleurs, la thèse met en exergue la spécificité du droit liégeois et tend à déterminer les influcences subies par ce droit. [less ▲]

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See detailDesign of a hydraulic nozzle with a narrow droplet size distribution
De Cock, Nicolas ULiege

Doctoral thesis (2017)

Nowadays, pesticides use is necessary to satisfy the growing demand for agricultural products. During pesticide spray application, the agricultural mixture containing the active ingredient is fragmented ... [more ▼]

Nowadays, pesticides use is necessary to satisfy the growing demand for agricultural products. During pesticide spray application, the agricultural mixture containing the active ingredient is fragmented to a cloud of droplets of various sizes and speeds. The droplet size distribution within the spray affects the efficiency of the treatment. According to the target, a specific droplet size should be used. However, hydraulic nozzles usually used in field application produce sprays with a wide droplet size distribution containing an important proportion of small or too large droplets. This results in non-optimal application and therefore losses of product into the environment. This statement conducted the research as early as in the 60’s to create the rotary atomizer. This device is able to produce narrow droplet size distribution using Plateau-Rayleigh break up mechanism. The characteristics of the produced spray by the rotary atomiser can be tuned by adjusting the rotational speed and the volumetric flow rate. Although offering agronomic and environmental qualities this has not met success for the application of plant protection products in field crops because of their cost, size and complexity. The aim of the thesis was the design of a hydraulic nozzle with the rotary atomizer qualities and without the constraints of rotating parts. Unlike the rotary atomizer which has two control variables, the developed hydraulic nozzle will have a narrower operating range, thus a specific geometry has to be design for each kind of treatment. The new hydraulic nozzle design is composed by an inlet pipe ending perpendiculary on a plate. There is a thin opening at the junction between the pipe and the plate. The edge of the plate is constituted of channels formed by structures. These channels aim to divide the liquid sheet in multiple jets. The breakup of these jets into droplets generate a narrow droplet size distribution. The thesis can been seen as a roadmap providing design tools at each step starting from the determination of an optimal droplet size according to the kind of treatment and ending with a nozzle geometry. The prediction of the optimal droplet size according to the treatment was done using integrated modelling approach of the spray transport and retention by the plant. As each spray requires a specific nozzle geometry, an analytical model of the flow on the nozzle was developed. This model allows the determination of geometry according to the desired spray. Finally, a prototype of nozzle has been built. The measurement of the spray characteristics of the prototype was realized using a developed high-speed imaging technique providing the droplet size and speed. The prototype showed results in term of narrowing of the droplet size distribution. [less ▲]

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See detailOn the design of waste heat recovery organic Rankine cycle systems for engines of long-haul trucks
Guillaume, Ludovic ULiege

Doctoral thesis (2017)

The reduction of CO2 emissions from anthropogenic activities is a strategic goal of the EU in which heavy duty vehicles can contribute in a relevant way. A promising solution is the recovery of the ... [more ▼]

The reduction of CO2 emissions from anthropogenic activities is a strategic goal of the EU in which heavy duty vehicles can contribute in a relevant way. A promising solution is the recovery of the thermal energy initially wasted by the engine, which represents around 60 % of the combustion energy. Transforming this heat into mechanical or electrical energy will thus increase the engine thermal efficiency. The conversion can be performed by means of a thermodynamic cycle (e.g. organic or non-organic Rankine cycles) using the waste heat as energy source, as it has already been developed in large stationary applications. Depending on the operating conditions, fuel consumption, and hence CO2 emissions, can theoretically be reduced by 10% to 15%. Nonetheless, the adoption of such technology in the automotive domain requires specific R&D activities to select the working fluid, the components and the most appropriate system architecture in order to achieve sustainable costs and the required level of reliability, while the transient nature of the heat sources available on the truck must be taken into account to evaluate the resulting fuel economy. In this regards, this thesis, based on experimental studies and simulation models, contributes to the characterization and the design of Waste Heat Recovery Organic Rankine Cycle Systems for engines of long haul trucks. [less ▲]

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See detailA TMS–EEG contribution to the multimodal assessment of brain connectivity and consciousness
BODART, Olivier ULiege

Doctoral thesis (2017)

Patients with chronic disorders of consciousness make a challenging population. On the clinical side, establishing an accurate diagnosis is arduous, as the signs of consciousness can be subtle, or even ... [more ▼]

Patients with chronic disorders of consciousness make a challenging population. On the clinical side, establishing an accurate diagnosis is arduous, as the signs of consciousness can be subtle, or even undetectable behaviourally. Both the families and the caregivers need truthful information to make tough decisions about the patient’s management. Transcranial magnetic stimulation, coupled with high-density electroencephalography, is a promising technique to improve our diagnostic ability. The perturbational complexity index derived from this technique is able to distinguish between unconscious and conscious conditions. Its specificity remains to be determined. On the scientific side, the long-standing quest to discover the neural correlates of consciousness is still ongoing. Patients with disorders of consciousness have structural brain damage, and several areas may lose their ability to causally interact in complex patterns with long distance structure. The relation between this ability and structural integrity remains undetermined, despite a vast amount of neuroimaging studies on several networks and connectivities in this population. Our objectives are i) to cross-validate the perturbational complexity index with other neuroimaging techniques, and to determine its specificity, and ii) to determine the relation between global structural integrity and the brain global ability to sustain complex long-range interactions. To do so, we first combined transcranial magnetic stimulation with fluoro-deoxyglucose positron emission tomography, a validated technique studying the brain metabolism, in a population of patients behaviourally characterized by repeated assessments with the gold standard scale, the coma recovery scale – revised. To meet our second objective, we computed and compared the perturbational complexity index and the global fractional anisotropy, a magnetic resonance imaging marker of structural integrity, in patients and in healthy subjects. We found an excellent congruence between electrophysiological and metabolic results in our first study, even in behaviourally unconscious patients showing indirect signs of consciousness. In our second study, we demonstrated that structural integrity largely correlated with the perturbational complexity index, and did not depend on the time since onset or the aetiology. This confirms the diagnostic value of transcranial magnetic stimulation and the perturbational complexity index. It is not only sensitive at the single subject level, but also highly specific. It can detect covert signs of consciousness, as confirmed by other neuroimaging techniques. As such, it could be integrated in diagnostic algorithms and improve their accuracy, leading to better management of these patients. Moreover, the brain’s ability to sustain complex long-range interactions is highly dependant on the global structural integrity. By looking further in detail at the local correlation between these two parameters, our understanding of the emergence of consciousness from fixed structure with variable connectivity would improve. This would be one step forward in the quest for the neural correlates of consciousness. [less ▲]

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See detailAn agent-based framework for modeling travel behavior under disrupted networks
Saadi, Ismaïl ULiege

Doctoral thesis (2017)

Worldwide, floods are the most frequent natural disasters and cause over one third of overall economic losses due to natural hazards. In addition, studies show that flood risk will further increase during ... [more ▼]

Worldwide, floods are the most frequent natural disasters and cause over one third of overall economic losses due to natural hazards. In addition, studies show that flood risk will further increase during the 21st century as a result of climate change. In this context, the objective of this thesis is to implement a methodological framework for modeling the impact of disrupted networks caused by river floods on travel demand. The manuscript is divided into four chapters. In the first chapter, this thesis contributes to the state-of-the-art by presenting an integrated multidisciplinary framework capable of making long-term projections (time horizon 2050 and 2100) with the objective of mitigating future flood risk. Various aspects of modeling are discussed with a focus on the interactions between the different model components. The second chapter is dedicated to multi-source data fusion in transportation research. Indeed, conducting large scale data collection is difficult and requires substantial financial resources. In practice, micro-samples with small sampling rates are generally used for synthesizing populations of households and individuals. Unfortunately, they present important limitations from a qualitative point of view, i.e. lack of representativeness. In this regard, a full population synthesis procedure based on Hidden Markov Model (HMM) has been designed to enable multi-source data fusion and incorporate more heterogeneity into eventual poor data-sets. Our research revealed that HMM outperforms IPF for all the sampling rates smaller than 25% regardless the scalability, while the amount of input data used by HMM is lower compared with IPF. The characterization of activity-travel patterns is described in the third chapter. Indeed, to enable a better understanding of travel behavior, a simulation-based approach for population synthesis has been coupled with a profile Hidden Markov Model (pHMM) in laying the foundation for an innovative activity-based model. There have been several key issues that deserved special attention, in particular the influence of socio-demographics on the activity-travel patterns. We also proposed new perspectives of validation techniques. The simulated and observed activity-travel patterns have been systematically compared on the basis of the emission and transition probabilities. The fourth chapter is dedicated to the case study. The synthesized population is used to calibrate a large scale scenario based on the agent-based framework MATSim to investigate the short-term impact of river floods on travel demand. The model has been tested for Liège, Belgium with multiple flood risk scenarios. Results reveal that the impact in terms of travel times is particularly significant when the network is operating at capacities lower than 50%. [less ▲]

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See detailCopper-based p-type semiconducting oxides: from materials to devices
Avelas Resende, João ULiege

Doctoral thesis (2017)

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See detailEffets de la fertilisation NP et de l'irrigation à des périodes critiques sur le rendement et la qualité des fruits du figuier de Barbarie (Opuntia ficus-indica (L.) Mill.)
Arba, Mohamed ULiege

Doctoral thesis (2017)

Selon la classification révisée récemment, les cactus appartiennent à la famille des Opuntiaceae Desv. (Synon. Cactaceae Juss.), dont le genre-type Opuntia Mill. est économiquement le plus important car ... [more ▼]

Selon la classification révisée récemment, les cactus appartiennent à la famille des Opuntiaceae Desv. (Synon. Cactaceae Juss.), dont le genre-type Opuntia Mill. est économiquement le plus important car il comprend un ensemble de variétés qui participent à la plupart des systèmes agricoles des régions arides et semi-arides. Récemment, dans le Maghreb, la culture de plusieurs espèces et variétés s'est développée à de fins de production fruitière commercialisable, c’est-à-dire répondant à des critères de qualité de plus en plus sévères et exigeant des technologies culturales précises. La partie expérimentale de notre étude s'est déroulée pendant deux années dans le Sud du Maroc, région d'Agadir, sur trois variétés représentatives. Les essais ont été réalisés à la ferme expérimentale de l'Institut Agronomique et Vétérinaire Hassan II, Complexe Horticole d'Agadir (30°36' Nord, 9°36' Est; altitude: 32 m). Le site est caractérisé par des températures moyennes mensuelles qui varient de 8°C en janvier à 31°C en juillet, la température journalière maximale pouvant atteindre 45°C en juillet-aout. La pluviométrie annuelle varie de 100 à 200 mm. La durée moyenne d'ensoleillement est de 8 heures par jour. Un premier objectif de notre étude a été de préciser les réponses quantitatives (rendement en fruits) et qualitatives à des apports modérés d'eau d'irrigation. Un deuxième objectif consistait à évaluer les effets d'apports limités de fertilisation minérale azotée et phosphatée, ces deux éléments majeurs étant les plus susceptibles de se trouver déficitaires dans le contexte pédoclimatique propre à la région. Un troisième objectif a été de préciser la phénologie des trois variétés - surtout les phases de développement floral et fruitier - afin de mettre en évidence d'éventuels impacts des interventions culturales sur la phénologie et de mieux situer les moments de ces interventions en les reliant de manière plus objective à la physiologie du développement. Dans l'étude sur l'irrigation, les variétés utilisées ont été les inermes 'Aissa' et 'Moussa' d'Opuntia ficus-indica (L.) Mill. et l'épineuse 'Achefri’ d’O. megacantha Salm Dyck. En première année, caractérisée par un printemps pluvieux, les traitements d'irrigation ont été: (T1) 0 mm, (T2) 30 mm à la floraison et 30 mm au grossissement des fruits et (T3) 30 mm seulement au grossissement des fruits; les irrigations ont été appliquées entre la mi-avril et la mi-juin. Les irrigations T2 et T3 ont eu un effet négatif sur le rendement en fruits des variétés inermes 'Aissa' et 'Moussa' (-2,8 kg/plant) et T2 a eu un effet positif hautement significatif (p <0,01) sur la variété épineuse 'Achefri’ (+ 2,7 kg/plant ou +18 %). La qualité des fruits n'a pas été affectée par l'irrigation. En deuxième année, caractérisée par un printemps sec, les traitements d’irrigation ont été: (T1) 0 mm, (T2) 60 mm à la floraison et 60 mm au grossissement des fruits et (T3) 60 mm seulement au grossissement des fruits; les irrigations ont été apportées entre février et mai. Toutes les variétés ont répondu positivement à l'irrigation, les augmentations de rendement très significatives (p <0,01) ont varié entre 30% pour 'Moussa' avec T2 et 63 % pour 'Achefri' avec T3 par rapport au témoin non irrigué. Toutes les irrigations ont augmenté le nombre et la taille des fruits et ont provoqué une légère diminution de la teneur en sucres totaux et de l'acidité titrable. Les irrigations n'ont eu aucun effet significatif sur les autres paramètres physiques, chimiques et organoleptiques participant à la définition de la qualité. L'essai sur la fertilisation minérale azotée-phosphorique sur le cultivar ‘Moussa’, mettait en comparaison cinq traitements: 0N-0P; 0N-80P; 40N-40P; 60N-0P et 60N-80P (en kg N ha-1- kg P2O5 ha-1). En première année, l'application de N et/ou de P n'a eu aucun effet sur le rendement en fruits. En deuxième année, les apports de 60 unités de N ou de 80 unités de P2O5 ont augmenté (p <0,01) le rendement de resp. 3,0 et 6,1 kg par plante (+ 18% et + 36%), par rapport au témoin. L'apport simultané des deux éléments N et P (60N-80P2O5) a conduit à une augmentation très significative (p <0,01) de 14,9 kg/plante (+ 90%) mettant en évidence une interaction positive très significative (p <0,01) entre ces deux éléments. Les apports de N et de P ont eu des effets positifs sur le nombre de fruits et leurs poids moyens mais ils n'ont pas modifié le contenu de la pulpe, la teneur en jus, l'épaisseur de l’écorce, la matière sèche du jus, le pH, l’acidité titrable, les sucres totaux, ni le °Brix. L'étude portant sur la phénologie et le développement a été effectuée simultanément dans un essai spécifique reprenant les trois variétés et dans chacun des essais d'irrigation et de fertilisation. Elle a d'une part permis de préciser la variabilité du déroulement des phénologies comme résultant des conditions de milieu (climat), de la génétique, des techniques culturales (fumure et irrigation), et de certaines de leurs interactions. Notre attention s'est portée prioritairement sur les effets des techniques culturales maîtrisables. En première année, les essais ont montré que l'émission de bourgeons est plus élevée (p<0,05) chez la variété épineuse que chez les inermes (plus de 6 bourgeons émis/cladode contre moins de 4,5 chez les variétés inermes). En 2ème année, l'irrigation a augmenté (p <0,05) l'émission de bourgeons chez les trois variétés (plus de 7 bourgeons émis/cladode pour chacun des traitements T2 et T3 vs pas plus que 5 pour T1). L'irrigation a aussi allongé la durée de la phase de floraison de ces variétés. La fertilisation a montré des effets allant dans le même sens. Cependant, ni l'irrigation, ni la fertilisation minérale n'ont modifié significativement la durée de la réalisation du stade maturité du fruit, ne permettant pas ainsi d'allonger la saison de récolte. [less ▲]

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See detailCaractérisations phénotypiques des populations de pintades (Numida meleagris) locales élevées au Bénin
Houndonougbo, Pascal ULiege

Doctoral thesis (2017)

La pintade (Numida meleagris) est une volaille d’origine africaine. Son élevage est répandu en Afrique subsaharienne dans un système traditionnel où plusieurs variétés sont élevées en liberté. Ces ... [more ▼]

La pintade (Numida meleagris) est une volaille d’origine africaine. Son élevage est répandu en Afrique subsaharienne dans un système traditionnel où plusieurs variétés sont élevées en liberté. Ces variétés qui diffèrent par le coloris de leur plumage sont très peu caractérisées. Au nord Bénin, l’élevage avicole moderne est peu rencontré et la pintade constitue la pondeuse d’œufs de table dans cette région. Mais, la mortalité élevée, la faible productivité de la pintade locale limitent fortement le développement de son élevage. Il est alors nécessaire de caractériser les variétés de pintades élevées pour mieux les valoriser dans un système amélioré. L’objectif de cette thèse est de caractériser phénotypiquement la population de pintade locale élevée au Bénin afin de mieux valoriser l’espèce dans des programmes d’amélioration et de développement du secteur avicole national. Une revue bibliographique (Article de synthèse) a permis de réaliser l’état des lieux de l’élevage de pintade au Bénin et de mieux orienter nos travaux pour une bonne caractérisation des variétés élevées. L’existence de plusieurs variétés dans les élevages a été soulignée dans la revue bibliographique et nous a amené à des enquêtes et un suivi des élevages de pintades en milieu villageois. Ces enquêtes et suivi nous ont permis de caractériser les pintades locales dans leur milieu d’élevage selon les dire des éleveurs. Ils nous ont aussi permis de dégager selon les éleveurs, les objectifs de production, l’importance socio-économique et culturelle des variétés élevées. L’influence de l’alimentation sur les performances technico-économiques des pintades locales a été soulignée dans l’Article de synthèse et l’Article I. Cette influence a été abordée en évaluant l’influence de l’alimentation sur le potentiel de croissance de la pintade locale en station (Article II). Enfin, des travaux ont été réalisés en station pour mieux caractériser les variétés de pintades rencontrées dans les élevages sur le plan morphologique, performances de croissance et de reproduction (Articles III, IV et V). Ces différents travaux nous ont permis de recenser les différentes variétés de pintades locales élevées au Bénin, les objectifs d’élevage des éleveurs ainsi que quelques difficultés liées au développement de cet élevage. Ces travaux nous ont surtout permis de mieux caractériser les variétés rencontrées. Cette caractérisation pourrait être valorisée pour améliorer la productivité des variétés par sélection. [less ▲]

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See detailEtude de la relation eaux de surface-eaux souterraines dans un contexte de changements climatiques dans la zone Sud du bassin du Saloum (Sénégal)
Dieng, Ndeye Maguette ULiege

Doctoral thesis (2017)

Situé dans la partie Centre-Ouest du Sénégal, le système hydrologique du Saloum, présente les caractéristiques d’un estuaire inverse du fait du déficit d’écoulement induit par la variabilité climatique ... [more ▼]

Situé dans la partie Centre-Ouest du Sénégal, le système hydrologique du Saloum, présente les caractéristiques d’un estuaire inverse du fait du déficit d’écoulement induit par la variabilité climatique dans la région. La salinité des eaux du fleuve Saloum, particulièrement élevée et supérieure à celle de l'eau de mer, a pour effet une détérioration de la nappe du Continental Terminal (CT) qui est une ressource très importante pour l’approvisionnement en eau potable (AEP) des populations locales mais également pour de grands projets de transfert d’eau vers les zones déficitaires comme les îles du Saloum. Cette présente a pour objectif d’à améliorer nos connaissances sur le fonctionnement hydrodynamique et hydrochimique de l’hydrosystème fleuve Saloum/nappe du CT et à évaluer sa dynamique dans le contexte de changement climatique. Plus spécifiquement, ces travaux visent à : (1) réactualiser les caractéristiques géométriques et hydrogéologiques de l’aquifère du CT en relation avec les eaux du fleuve Saloum, (2) caractériser la salinisation de la nappe du CT, (3) élaborer un modèle hydrogéologique permettant une évaluation des potentiels et des relations eau de surface/nappe à partir de simulations de prélèvements supplémentaires et de scénarios de changements climatiques. L’approche méthodologique utilisée pour atteindre ces objectifs intègre à la fois les aspects sur la télédétection et les SIG, la géochimie des éléments majeurs et isotopiques, l’analyse statistique multivariée et la modélisation. Les méthodes du bilan des chlorures et de Penman utilisées pour l’estimation de la recharge donnent des valeurs comprises, respectivement, entre 17 et 100 mm/an et 19 et 130 mm/an. Ces valeurs ont été spatialement distribuées sur les zones potentielles de recharge fournies par la cartographie. L’analyse statistique par les « Selfs organizinf Map » (SOM) des données géochimiques a permis de distinguer trois types d'eaux souterraines : le groupe 1 (Na-Cl ou Ca-Cl) localisé le long du littoral et du fleuve Saloum est affecté par l’intrusion d’eau salée et/ou une pollution anthropique ; le groupe 2 (Ca-HCO3), principalement situé dans les parties centrale et orientale est caractérisé par une minéralisation résultant de la dissolution de la calcite et enfin le groupe 3 qui indique des processus d’adoucissement susceptibles de représenter l'effet de l’infiltration des pluies récentes. Ces résultats corroborés par l’isotopie montrent une grande variabilité spatiale de la minéralisation des eaux et une certaine cohérence avec le schéma de fonctionnement hydrodynamique établi pour la nappe. L’ensemble des informations apportées par ces différentes approches a été intégré pour développer un modèle conceptuel du fonctionnement hydrogéologique du système qui a été traduit en modèle numérique. Ce dernier est calibré en régime permanent (1970-1973) qui constitue les conditions initiales de la période transitoire (1974-2012). Les résultats montrent que les eaux de pluie, les eaux salées fluviatiles et marines constituent les principales entrées de la nappe. Quant aux flux sortants, ils sont constitués par les pompages (puits et forages) et la décharge de la nappe vers les cours d’eau, la mer et le fleuve Saloum. La légère baisse du niveau piézométrique entre 1974 et 1984 serait le fait du déficit pluviométrique observé depuis les années 70 et de l’augmentation des pompages qui passent de 370 m3/jour en 1974 à 2750 m3/jour en 1985. Durant cette période, les apports proviennent en grande partie de l’intrusion d’eau salée (87 %). A partir de 1986 avec des conditions climatiques plus favorables, on observe une baisse de l’intrusion des eaux salées (11 % des apports) et une remontée du niveau piézométrique, malgré l’augmentation des pompages qui atteignent plus de 8500 m3/jour en 2012. Les simulations prédictives de 2013 à 2050 ont montré que l’effet combiné de l’augmentation des pompages (de l’ordre de 45 %) et de la baisse de la recharge (36 % en moyenne) entraîne des baisses piézométriques variables en fonction des zones considérées. Ce modèle, pourrait être outil d’aide à la décision pragmatique pour une meilleure gestion et orientation pour l’exploitation future de la nappe du CT. [less ▲]

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See detailAnalyse comparée des chaines de valeur du riz dans la plaine de la Ruzizi de la Communauté Economique des pays des Grands Lacs (CEPGL)
Furaha Mirindi, Germaine ULiege

Doctoral thesis (2017)

This thesis aims at carrying out a comparative study of three rice value chains in the Ruzizi plain shared between three countries of the Economic Community of the Great Lakes Countries (CEPGL) namely ... [more ▼]

This thesis aims at carrying out a comparative study of three rice value chains in the Ruzizi plain shared between three countries of the Economic Community of the Great Lakes Countries (CEPGL) namely Burundi, the Democratic Republic of Congo and Rwanda. These include the Burundi rice value chain (Imbo Plain), the Congolese rice value chain (Ruzizi Plain) and the Rwandan rice value chain (Bugarama Plain). The diagnostic analysis was about analyzing the rice-farming environment (ie policies and support services accessed by actors along the value chain), analyzing economic performance of these three value chains and to identify the factors that may foster the development of a value chain with a regional potential. For this purpose, the study adopted the field approach, which allowed carrying out investigations during three years (2013 to 2015). The data collection process involved a sample of 228 actors distributed equitably among the three countries. It combined several techniques, namely, direct stakeholder surveys (producers, processors, collectors, wholesalers and retailers), interviews with various support structures and state services, focus group discussions with producer groups and representatives of their organizations. The analysis of these three value chains driving conditions linked the policies implemented in each country and the access by the actors to certain production factors and services such as land, water, credit and the use of inputs. It also highlighted the issue of wage labor and its different roles in the sector. The analysis shows that land policy in Bugarama plain in Rwanda has reduced the cost of land to more than half compared to land costs in Burundi and the DRC. Moreover, this policy is accused by the producers of Bugarama of limiting their entrepreneurial innovations since they can not enlarge their farms (the cultivated area is 0.23 ha). Despite the high cost of water access and management, all rice plots access irrigation water in Rwanda, while the lack of organization and good water management is one of the factors behind low yields in Burundi and the DRC, where 25% and 40% of the rice plots have difficulties in accessing water. Regarding access to agricultural credit, the results reveal that the value chain of rice in the three countries experiences the lack of funding in spite of improvements observed in Rwanda. The rate of access to credit is 17.5% (in Burundi), 16% (in DRC) and 52.8% (in Rwanda), and among them rice farmers with access to formal credits account for only 8% (in Burundi), 10% (in the DRC) and 37.5% (in Rwanda). Analysis of the wage labour force shows that labor is not as widely available as was thought in the study area. Indeed, the DRC is the zone of deficit in wage labor due to the rural exodus and the diversity of economic activities. In the DRC, 60% of the rice workforce used is foreign, including 46% from Burundi and 14% from Rwanda. This mobility of the workforce leads to technology transfers, the supply of inputs at lower cost, but also to consolidate the social cohesion in a post-conflict context. The economic analysis of these three value chains reveals that production costs in the study area remain very high, varying between 292 and 388USD per ton. The highest costs are observed in the DRC where paradoxically there is a better financial performance in terms of profit and added value. The statistical tests carried out on certain parameters identified by the financial analysis undermines the policies regarding the inputs subsidies, agricultural financing and fixing sales prices. Indeed, there are no significant differences between the means of rice farmers who benefit from these policies and those who do not. Paradoxically, statistical analyzes reveal that rice farmers not affected by the pricing policy (they are not price takers) have a good financial performance in terms of income. The three studied areas are complementary in terms of the development potentials of a regional value chain. Indeed, Rwanda has modern underutilization peeling plants that are capable of responding almost entirely to the needs of the whole plain. In addition, Burundi and the DRC should develop land and water potentials to increase production. Several other regional structures in favor of the regional value chain have to be relaunched or strengthened in logic of rice development in the Ruzizi plain. These include the benefits of economic integration of the CEPGL countries. [less ▲]

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See detailWalking droplets above cavities
Filoux, Boris ULiege

Doctoral thesis (2017)

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See detailLe rôle de la pleine conscience dans l’accompagnement de patients obèses : Quand, pourquoi et comment intervenir ?
Ruffault, Alexis ULiege

Doctoral thesis (2017)

Exposure to adverse life events has been associated with adult obesity, and could translate into the appearance of eating disorders. Moreover, exposure to adverse life events has been associated with ... [more ▼]

Exposure to adverse life events has been associated with adult obesity, and could translate into the appearance of eating disorders. Moreover, exposure to adverse life events has been associated with emotional dysregulation, which would be in turn linked to higher prevalence of eating disorders. Furthermore, mindfulness skills (i.e., non-judgmental awareness of thoughts, emotions, and bodily sensations in the present-moment) have been the object of increased attention in the scientific literature as a means to increase emotion regulation and treat eating disorders in obese patients. The first part of this thesis studies the associations of exposure to adverse life events with eating patterns in obese patients. Two studies have been conducted in this part : the first aiming at assessing the association of exposure to adverse life events with postoperative weight-loss, as well as pre- and postoperative eating patterns ; and the second aiming at exploring the role of emotion regulation strategies and mindfulness skills in the association of exposure to adverse life events and eating patterns. The second part studies the effects of mindfulness training on eating patterns and physical activity in obese patients. Three studies have been conducted in this part : a clinical case study, a systematic review and meta-analysis, and a randomized controlled trial (MindOb study). The results of the first part showed that bariatric surgery patients exposed to adverse life events are at risk of losing less weight after surgery, as well as having more dysfunctional eating patterns pre- and postoperative. Moreover, with non-operated obese patients, the results showed that the psychological impact of adverse life events and nonadaptive emotion regulation have been associated with psychological distress, impulsive eating, and binge eating. The results of the second part showed that mindfulness training decreased impulsive and binge eating in non-operated patients. Moreover, results showed that mindfulness training could also increase physical activity in these patients. This thesis highlights the need for providing obese patients with psychotherapeutic techniques increasing emotion regulation. The results suggest that pre-surgery interventions could avoid maintenance or the appearance of dysfunctional eating patterns. Moreover, psychotherapeutic interventions would be more effective in the case of patients either exposed to adverse life events or being diagnosed with binge eating disorder. However, while mindfulness training seemed effective, the optimal intervention design has yet to be identified. In fact, the questions of whether such training should be self-help or guided, daily and long-term or short-term, complementary tomedical care and adapted to eating disorders or broader, must still be tested. [less ▲]

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See detailAdvanced porosity-based models to assess the influence of urban layouts on inundation flows and impact of urban evolution on flood damage
Bruwier, Martin ULiege

Doctoral thesis (2017)

Worldwide, flood risk is expected to increase over the 21st century due to the combined effect of climate and land use changes. However, while the impact of climate change on future flood risk was ... [more ▼]

Worldwide, flood risk is expected to increase over the 21st century due to the combined effect of climate and land use changes. However, while the impact of climate change on future flood risk was extensively studied, the effects of urbanization remain unclear. The goal of this PhD thesis is to contribute to a better understanding of the influence of future urban development on changes in inundation flows as well as on the related damage. First, an original porosity-based model was developed, which enables efficient computation of urban flooding. It uses anisotropic porosity parameters to reproduce the influence of subgrid-scale obstacles on the flow. An original merging technique was implemented to optimize the computational efficiency in the presence of low values of the storage porosity parameter. Compared to a standard inundation model, the developed model enables speedup factors of the order of 100, while keeping the error on the flow variables at a few percent. Second, we systematically investigated how the layout of buildings located in floodplains influences the inundation characteristics for a long-duration flood scenario. The anisotropic porosity-based model was used to compute the flow variables for 2,000 alternative urban patterns. Correlations between the computed water depths and the urban characteristics reveal which features of the layout of buildings influences most the severity of urban flooding. In particular, the results suggest how the hydraulic effect of new urban development can be effectively mitigated by a suitable location of the buildings preserving a higher flow conveyance at the district-scale. This result provides guidance for more flood-proof urban developments. Finally, we evaluated the evolution of future flood damage as a result of urbanization along all the main rivers in the Walloon region, Belgium. The study was conducted at the regional level using detailed hydraulic results (resolution of 2 to 5 m). Despite high uncertainties in the considered urbanization scenarios, involving both urban expansion and densification, robust conclusions could be drawn, such as the overwhelming influence of banning new developments in flood-prone areas compared to the other tested facets of urban planning policy. [less ▲]

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See detailDevelopment of functionalized materials through sol-gel route for applications in catalysis and surface protection
Léonard, Géraldine ULiege

Doctoral thesis (2017)

In this work, materials have been produced by sol-gel route. This synthesis way has been used for immobilization on a support of a function focused on green chemistry. The different functions are related ... [more ▼]

In this work, materials have been produced by sol-gel route. This synthesis way has been used for immobilization on a support of a function focused on green chemistry. The different functions are related with different applications that allow to illustrate the versatility and the flexibility of this sol-gel process. The two applications are: - Photocatalysis: Synthesis of material with photocatalytic property or with an additional property - Cyclocarbonation: Synthesis of an immobilized catalyst for polyurethane production through a green process The first application concerns the use of a photocatalyst that allows to degrade volatile organic compounds (VOC). The main photocatalyst is TiO2. It has been studied as a powder or as a film deposited on a support. A comparison of these two shapes has shown that an identical photocatalyst can have different performances depending on the final shape. A catalyst must be considered in its totality and with its environment rather than as a chemical composition only. To increase the photocatalyst performances, modifications have been added as the Zn doping to increase the photocatalytic activity and the superhydrophilicity. These new photocatalysts have been compared with pure ZnO and bilayer films composed of TiO2 and of ZnO. Different photocatalytic tests have been performed and depending on the test the best photocatalyst was different. Then, to increase the economic interest, some dopant have been used. In addition of the improvement of the photocatalytic activity and superhydrophilicity, theses dopants add a new property such as electrical conductivity and anticorrosion. First, metallic silver has been incorporated to add antistatic property and to increase the photocatalytic activity. The photocatalytic property has been improved, superhydrophilicity has been kept but no antistatic property was observed. Multiwall carbon nanotubes (MWCNTs) have been tested with TiO2 to increase the electrical conductivity. This doping is efficient because MWCNTs increase the conductivity, the photocatalytic activity and maintain the superhydrophilicity. In addition, anticorrosive property has been observed on stainless steel in a preliminary study with the MWCNTs incorporation. The second study is focused on the heterogeneous cyclocarbonation catalyst synthesis to produce, in fine, polyurethane. The catalyst was immobilized on different matrices that are inert from catalytic point of view but that have a potential activator effect. First, with the preselected catalyst, different supports have been investigated. The comparison between the supports has highlighted the activator effect and the texture influence (accessibility of the active sites) on cyclocarbonation yields. Then, with the optimal matrix, different catalysts from a same family have been grafted to choose the best catalyst. Therefore, it has been possible to define the best catalyst and the best support. With this combination, a kinetic study has been performed to determine the best experimental conditions to produce cyclocarbonates. [less ▲]

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See detailCapturing fine-scale population structure towards molecular reclassification of patients
Chaichoompu, Kridsadakorn ULiege

Doctoral thesis (2017)

During the past decades, population structure analysis has been playing an important role for stratifying populations and tracking back population ancestries. Population structure is mainly due to non ... [more ▼]

During the past decades, population structure analysis has been playing an important role for stratifying populations and tracking back population ancestries. Population structure is mainly due to non-random mating between subgroups in a population because of various reasons, being of social, cultural, or geographical nature. Genetic structure in populations may also arise from known or unknown family relationships. Complex disease analyses, in case-control genetic association studies particularly, can be affected by so-called cryptic relatedness, which refers to unobserved ancestral relationships between study individuals. As population structure may confound results from genetic association studies and studies that aim to detect clinically relevant substructure in patients, its detection is highly relevant. Revealing population structure is really essential. Notably, removing unwanted population structure in molecular-based patient subtypes detection is likely to lead to subtle or fine-scale remaining structure. In this thesis, we developed a novel genetic structure detection tool, hereafter referred to as IPCAPS, which can also be used as, or extended to, a tool for fine-scale reclassification of patients. IPCAPS utilizes a fixation index (FST) to measure the distance between clusters for iterative loop termination. An FST > 0.001 is typically seen as evidence for genetic differentiation between European populations. We also introduced a novel heuristic called EigenFit as one of the stopping criteria. Although our tool has been developed to easily accommodate multiple data types, we have illustrated the conception of IPCAPs and its performance on simulated and real-life data using panels of genome-wide SNP data. SNPs, standing for Single Nucleotide Polymorphisms, are the most common type of genetic variation among people. There are roughly 10 million of them. We evaluated the performance of IPCAPS using a variety of simulation studies and simulation scenarios, including varying sample sizes, varying SNP panel sizes, the absence or presence of outliers, large or very small genetic separation between synthetic populations. The performance of IPCAPS was measured by estimating accuracy and computation time. We observed that our method generally outperformed a selection of other iterative pruning based methods such as ipPCA, iNJclust, and SHIPS. Also in the presence of outliers, IPCAPS' computation time is largely affected by sample size, not by the number of SNPs included in the analysis. We furthermore validated our tools and proposed protocols on a variety of real-life datasets. These datasets differed in complexity and ranged from worldwide sample collections, over regional populations, to geographically confined samples. In particular, we analyzed data from the International HapMap Project, the 1000 Genomes Project, Africa and Thailand. We proposed a suitable protocol to correct for population stratification and to perform patient subgrouping in samples from the International IBD Genetics Consortium (IBD referring to inflammatory bowel disease). All developed analysis protocols involved guidelines for the interpretation of identified strata. In conclusion, IPCAPS is a promising structure detection analysis tool. It was able to identify fine structure in African and HapMap populations, previously unreported. IPCAPS analysis also suggested the presence of at least 3 subtypes of Crohn’s disease and at least 3 subtypes of Ulcerative Colitis patients. More work is needed to evaluate the importance of these findings in clinical practice and for precisions medicine. [less ▲]

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See detailA Combining Approach to Cover Song Identification
Osmalsky, Julien ULiege

Doctoral thesis (2017)

This thesis is concerned with the problem of determining whether two songs are different versions of each other. This problem is known as the problem of cover song identification, which is a challenging ... [more ▼]

This thesis is concerned with the problem of determining whether two songs are different versions of each other. This problem is known as the problem of cover song identification, which is a challenging task, as different versions of the same song can differ in terms of pitch, tempo, voicing, instrumentation, structure, etc. Our approach differs from existing methods, by considering as much information as possible to identify cover songs. More precisely, we consider audio features spanning multiple musical facets, such as the tempo, the duration, the harmonic progression, the musical structure, the relative evolution of timbre, among others. In order to do that, we evaluate several state-of-the-art systems on a common database, containing 12,856 songs, that is a subset of the Second Hand Song dataset. In addition to evaluating existing systems, we introduce our own methods, based on global features, and making use of supervised machine learning algorithms to build a similarity model. For evaluating and comparing the performance of 10 cover song identification systems, we propose a new intuitive evaluation space, based on the notions of pruning and loss. Our evaluation space allows to represent the performance of the selected systems in a two dimensional space. We further demonstrate that it is compatible with standard metrics, such as the mean rank, the mean reciprocal rank and the mean average precision. Using our evaluation space, we present a comparative analysis of 10 systems. The results show that few systems are usable in a commercial system, as the most efficient is able to identify a match at the first position for 39% of the analyzed queries, which corresponds to 4,965 songs. In addition, we evaluate the systems when they are pushed to their limits, by analyzing how they perform when the audio signal is strongly degraded. To improve the identification rate, we investigate ways of combining 10 systems. We evaluate rank aggregation methods, that aim at aggregating ordered lists of similarity results, to produce a new, better ordering of the database. We demonstrate that such methods produce improved results, especially for early pruning applications. In addition to evaluating rank aggregation techniques, we propose to study combination through probabilistic rules. As the 10 selected systems do not all produce probabilities of similarity, we investigate calibration techniques to map scores to relevant posterior probability estimates. After the calibration process, we evaluate several probabilistic rules, such as the product, the sum, and the median rule. We further demonstrate that a subset of the 10 initial systems produces better performance than the full set, thus showing that some systems are not relevant to the final combination. Applying a probabilistic product rule to a subset of systems significantly outperforms any individual systems, on the considered database. In terms of direct identification (top-1), we achieve an improvement of 10% (5,460 tracks identified), and in terms of mean rank, mean reciprocal rank and mean average precision, we respectively improve the performance by 40%, 9.5%, and 12.5%, with respect to the previous state-of-the-art performance. We further implement our final combination in a practical application, named DISCover, giving the possibility for a user to select a query and listen to the produced list of results. While a cover is not systematically identified, the produced list of songs is often musically similar to the query. [less ▲]

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See detailCaractérisation de disques de poussière exozodiacale par interférométrie stellaire en infrarouge proche et moyen
Marion, Lindsay ULiege

Doctoral thesis (2017)

Nous savons aujourd’hui que notre système solaire n’est pas un cas isolé dans la galaxie et qu’il pourrait potentiellement en exister des milliers d’autres. La recherche de ces systèmes est devenue un ... [more ▼]

Nous savons aujourd’hui que notre système solaire n’est pas un cas isolé dans la galaxie et qu’il pourrait potentiellement en exister des milliers d’autres. La recherche de ces systèmes est devenue un centre d’intérêt majeur de la recherche en astrophysique au XXIème. La présence de poussière chaude et tiède est étroitement liée à la présence de planètes dans un système stellaire. En effet, elle provient généralement de la formation du système planétaire, du dégazage de comètes, et de collisions d’astéroides, comme c’est le cas dans notre système solaire. Il est donc devenu primordial de détecter et caractériser la poussière tiède/chaude autour d’étoiles en séquence principale. L’intérêt de l’étude des disques de débris tièdes/chauds est double : d’une part, les détecter et les caractériser nous permet d’obtenir plus d’informations sur la formation d’un éventuel système planétaire et sur la dynamique du système (mécanisme de piégeage de la poussière, ré-approvisionnement du disque de poussière chaudes à partir d’un disque de poussière plus froide, plus éloigné, présence de planètes qui nettoient le disque interne, etc) ; d’autre part, les disques de débris tièdes/chauds peuvent complètement masquer une planète lors de tentatives de détection en imagerie directe. Il convient donc de les détecter pour discriminer ces étoiles pour les missions futures de détection d’exoplanètes par imagerie directe. Le présent travail vise à poursuivre l’étude des disques tièdes/chauds commencée au début des années 2000. Dans un premier temps, nous recherchons la présence de compagnon au sein de l’échantillon d’étoiles dédiées au programme de détection d’exozodis afin de fournir un échantillon non biaisé pour la recherche de disques de débris tièdes/chauds. Grâce aux détections de compagnons, nous révisons également la statistique d’étoiles binaires de type spectral A. Ensuite, dans un nouvel échantillon défini spécifiquement à cet effet, nous étudions la corrélation possible entre présence de poussière tiède et chaude. Nous arrivons à la conclusion qu’il existe une corrélation entre présence de poussière tiède et chaude et que la poussière tiède pourrait donc servir de réservoir à la poussière chaude. Toutefois, pour confirmer ce résultat, d’autres études devront être menées. Ensuite, nous résumons les avancées réalisées au LBTI et mettons en exergue les progrès réalisés sur la méthode statistique de traitement de données pour des observations de nulling. Enfin, nous étudions le système de beta Pic au travers d’observations dans l’infrarouge moyen réalisées avec MIDI. Cette étude nous permet de conclure qu’il n’y a pas de poussière tiède dans les zones internes (~ 1.5 UA) du disque de Pic et que la poussière chaude qui cause un excès en infrarouge proche est probablement alimentée par le dégazage de comètes envoyées dans le système stellaire interne par la planète se trouvant aux environs de 9 UA. [less ▲]

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See detailDroplet manipulation on a fiber network
Weyer, Floriane ULiege

Doctoral thesis (2017)

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See detailPhysical properties of L-type asteroids: a link to the primordial Solar System?
Devogele, Maxime ULiege

Doctoral thesis (2017)

A few years ago, asteroid polarimetry allowed to discover a class of asteroids exhibiting peculiar phase polarization curves, collectively called "Barbarians" from the prototype of this class, the ... [more ▼]

A few years ago, asteroid polarimetry allowed to discover a class of asteroids exhibiting peculiar phase polarization curves, collectively called "Barbarians" from the prototype of this class, the asteroid (234) Barbara. All such objects belong to the L visible plus near infrared based taxonomic class. The anomalous polarization has been tentatively interpreted in terms of high-albedo, spinel-rich Calcium-Aluminum inclusions (CAI) that could be abundant on the surfaces of some of these asteroids, according to their spectral reflectance properties and to analogies with CO3/CV3 meteorites. Such CAIs are among the oldest mineral assemblages ever found in the Solar System. Barbarians' surfaces could therefore be rich in this very ancient material and bring information on the early phases of planetary formation. During this thesis, a systematic campaign for photometric, polarimetric and spectroscopic characterization has been conducted. These observation campaigns allowed improving our general knowledge about these peculiar asteroids and highlighting the link between polarization and polarimetric properties. Our observation also allowed discarding the hypotheses involving peculiar shape for these asteroids. However, as it was suggested, a link between the presence of CAI and the polarimetric response was found. Our observations show that the relative abundance of CAI is correlated with the polarimetric inversion angle. This is the first time that a direct link between polarimetric and spectroscopic properties is found. [less ▲]

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See detailWohnmobilität in der Großregion -- eine interurbane Diskursanalyse mit Fokus auf den Städten Arlon, Thionville und Trier.
Christmann, Nathalie ULiege

Doctoral thesis (2017)

[en] Effects of residential mobility moulding in uneven development in border regions can be perceived very differently by city councils or planners and the local population. This dissertation focuses on ... [more ▼]

[en] Effects of residential mobility moulding in uneven development in border regions can be perceived very differently by city councils or planners and the local population. This dissertation focuses on the perceptions of population mobility and dwelling in a transnational cross-border polycentric region in western Europe. The economic development of the Grand Duchy of Luxembourg calls for a constant expansion of the labour market, attracting cross-border commuters and highly mobile professional elites. The concomitant rises in property prices as well as the extreme housing shortages in Luxembourg have led to an expansion of the housing market into the border regions. So far studies have mostly dealt with the socio-demographic characteristics of the transmigrants. This research aims to detect people's perceptions of the phenomenon by applying a discourse analysis, thus aiming to trigger an increasing awareness for the emerging transnational housing market. [less ▲]

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See detailComputer vision systems for automatic analysis of face and eye images in specific applications of interpretation of facial expressions
Hoyoux, Thomas ULiege

Doctoral thesis (2017)

This thesis is about the computer vision-based automation of specific tasks of face perception, for specific applications where they are essential. These tasks, and the applications in which they are ... [more ▼]

This thesis is about the computer vision-based automation of specific tasks of face perception, for specific applications where they are essential. These tasks, and the applications in which they are automated, deal with the interpretation of facial expressions. Our first application of interest is the automatic recognition of sign language, as carried out via a chain of automatic systems that extract visual communication cues from the image of a signer, transcribe these visual cues to an intermediary semantic notation, and translate this semantic notation to a comprehensible text in a spoken language. For use within the visual cue extraction part of such a system chain, we propose a computer vision system that automatically extracts facial communication cues from the image of a signer, based on a pre-existing facial landmark point tracking method and its various robust refinements. With this system, our contribution notably lies in the fruitful use of this tracking method and its refinements within a sign language recognition system chain. We consider the facial communication cues extracted by our system as facial expressions with a specific interpretation useful to this application. Our second application of interest is the objective assessment of visual pursuit in patients with a disorder of consciousness. In the clinical practice, this delicate assessment is done by a clinician who manually moves a handheld mirror in front of the patient's face while simultaneously estimating the patient's ability to track this visual stimulus. This clinical setup is appropriate, but the assessment outcome was shown to be sensitive to the clinician's subjectivity. For use with a head-mounted device, we propose a computer vision system that attaches itself to the clinical procedure without disrupting it, and automatically estimates, in an objective way, the patient's ability to perform visual pursuit. Our system, combined with the use of a head-mounted device, therefore takes the form of an assisting technology for the clinician. It is based on the tracking of the patient's pupil and the mirror moved by the clinician, and the comparison of the obtained trajectories. All methods used within our system are simple yet specific instantiations of general methods, for the objective assessment of visual pursuit. We consider the visual pursuit ability extracted by our system as a facial expression with a specific interpretation useful to this application. To some extent, our third application of interest is the general-purpose automatic recognition of facial expression codes in a muscle-based taxonomic coding system. We do not actually provide any new computer vision system for this application. Instead, we consider a supervised classification problem relevant to this application, and we empirically compare the performance of two general classification approaches for solving this problem, namely hierarchical classification and standard classification ("flat" classification, in this comparative context). We also compare these approaches for solving a classification problem relevant to 3D shape recognition, as well as artificial classification problems we generate in a simulation framework of our design. Our contribution lies in the general theoretical conclusions we reach from our empirical study of hierarchical vs. flat classification, which are of interest for properly using hierarchical classification in vision-based recognition problems, for example for an application of facial expression recognition. [less ▲]

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