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Temporomandibular disorders (TMDs) can substantially reduce one’s quality of life and lead to both persistent pain and psychological distress. However, TMDs are often overlooked and poorly understood. There are wide variations in the severity, duration, and distribution of pain in individuals with TMDs. These variations are believed to be better explained by central sensitization – that is, the enhanced sensitivity of neurons in the central nervous system – than by the extent of tissue damage or biomechanical dysfunctions in the masticatory system. The objective of this thesis is to improve the understanding of central-pain mechanisms in persistent TMDs and unravel the potential role of central sensitization. We will focus specifically on temporomandibular myalgia (TMDm), which is the most common subtype of TMDs. First, we seek, examine, and summarize the best available evidence on central sensitization and persistent TMDm. We find that, on average, individuals with persistent TMDm have an increased mechanical temporal summation in the upper limb but few other somatosensory abnormalities that are believed to reflect central sensitization. Second, we investigate the reliability of a promising experimental model to study central sensitization in humans. This model, called high-frequency electrical stimulation (HFS), induces secondary mechanical hyperalgesia. Based on animal studies, secondary mechanical hyperalgesia can confidently be attributed to central sensitization. We identify the most reliable features of secondary mechanical hyperalgesia induced by HFS. We also demonstrate that HFS is suitable to discriminate or compare individuals with respect to their propensity to develop central sensitization. Third, we assess the impact of HFS-induced central sensitization on pressure pain thresholds. Central sensitization induced by HFS does not alter pressure pain thresholds. While derived from an experimental model, this finding contradicts the common view that a wides, (MOTR - Sciences de la motricité) -- UCL, 2023

Low back pain is currently the leading cause of disability and absence from work. Physical activity (PA) has shown to be effective for the management of chronic low back pain (CLBP). However, PA remains understudied in low-income countries. We investigated (1) the influence of biopsychosocial factors on activity limitations related to CLBP in Burundi, (2) the biomechanical profile of yoga postures and (3) the effectiveness of collective brisk walking plus yoga (BW+Y) for the management of CLBP. The results highlighted that (1) biopsychosocial factors predict activity limitations related to CLBP, (2) the biomechanical profile of yoga postures provides useful information that help to choose specific yoga program for low back pain management, and (3) collective BW+Y significantly improved the impairments, activity limitations, and participation restrictions related to CLBP in Burundi., (MOTR - Sciences de la motricité) -- UCL, 2023

Stroke is the first leading cause of disability in adults worldwide (GBD, 2021), and low-income countries are the most affected. In these countries, access to health care, particularly rehabilitation, is a great challenge. As the prevalence of stroke is increasing and the number of stroke survivors is rising, the economic charge of stroke rehabilitation will continue to expand, unless appropriate strategies are developed. This thesis contributed by mapping the clinical profile of stroke survivors from a sub-Saharan Africa low-income country to raise awareness of a critical need for cost-effective and accessible rehabilitation intervention. In addition, this thesis demonstrated the feasibility and effectiveness of a mixed community and group-based physical activity intervention. This community-based physical activity would be an efficient way to improve access to rehabilitation in low-income countries., L'accident vasculaire cérébral (AVC) est la première cause de handicap chez l'adulte dans le monde (GBD, 2021) et les pays à faible revenu sont les plus touchés. Dans ces pays, l'accès aux soins de santé, et notamment à la réadaptation, est un grand défi. Comme la prévalence de l'AVC ne cesse d’augmenter et par conséquent, le nombre de survivants d'AVC, la charge économique de la réadaptation post-AVC continuera de croître, à moins que des stratégies appropriées ne soient développées. Cette thèse a contribué à la description du profil clinique des survivants d'un AVC dans un pays à faible revenu d'Afrique subsaharienne, afin de sensibiliser au besoin d’interventions de réadaptation rentable et accessible. En outre, cette thèse a démontré la faisabilité et l'efficacité d'une intervention mixte d'activité physique réalisée en communauté et en groupe. Cette activité physique communautaire serait un moyen efficace d'améliorer l'accès à la réadaptation dans les pays à faible revenu., (MOTR - Sciences de la motricité) -- UCL, 2023

"My breathing has not changed, I am still very breathless". It is not uncommon to hear these words from patients with chronic obstructive pulmonary disease despite optimal pharmacological treatment. For these patients, breathlessness becomes a constant experience that worsens over time and becomes frightening. This refractory breathlessness, notably during physical activities, is a real problem as it can reduce adherence to therapeutic strategies such as pulmonary rehabilitation. The primary aim of this thesis is to look at different ways in some component of dyspnoea can be addressed to help patients better tolerate their breathlessness during exercise and improve their functional capacity. The first and second study discuss the effect of nasal high flow during exercise (improving ventilatory efficiency). The third study assess the impact of menthol on exertional dyspnoea (affective component). The fourth study evaluate the effects of an energy conservation technique on breathlessness and on the physiological response when patients with severe COPD climb stairs (reduction of ventilatory demand)., (MOTR - Sciences de la motricité) -- UCL, 2022

Cancer progression is influenced by the physico-chemical features of the tumor microenvironment. Considered as a major hallmark of cancer, tumor acidosis results from an exacerbated glycolytic metabolism and an insufficient clearance of protons by the vasculature. Hence, tumors have been described as more acidic than healthy tissues. Cancer cells will shift their metabolic preferences from glucose towards fatty acids (FAs) to adapt to this hostile environment and thereby will gain further advantages to survive, proliferate and metastasize. We examined whether promoting an excess uptake of specific FAs could lead to antitumor effects in these acidosis-adapted cancer cells. We found that n-3 but also n-6 polyunsaturated FAs (PUFAs) selectively induced ferroptosis in cancer cells under ambient acidosis. Upon exceeding the buffering capacity of lipid droplets, n-3 and n-6 PUFA peroxidation accounted for cytotoxic effects and even more so if their storage or beta-oxidation was inhibited. Finally, an n-3 PUFA-rich diet significantly delayed mouse tumor growth when compared to a control diet. The therapeutic potential of PUFA supplementation was further evaluated by studying the administration of n-3 PUFA-rich capsules to human volunteers. Altogether, our data point out dietary PUFAs as a selective adjuvant antitumor modality that may efficiently complement pharmacological approaches., (AGRO - Sciences agronomiques et ingénierie biologique) -- UCL, 2022

The perfect instrument in spectroscopy measures spectra with high-resolution, high-sensitivity and in a small amount of time over a broad spectral range. Fourier-transform spectrometers (FTS) allow for both high resolution and broadband measurements thanks to their multiplex advantage. By coupling the light source to an optical cavity, the sensitivity of the instrument is considerably increased since the interaction length of the light with the sample is increased by several orders of magnitude (reaching kilometric interaction lengths). The use of frequency combs allows to increase the precision of the measurement and to surpass the maximum resolution of conventional FTS. Finally, when performing spectroscopy of complex molecules in the gas phase at high resolution, spectra are highly congested because many energy levels are populated, allowing a great number of transitions to occur. This results in difficulties to assign each transition to its corresponding energy levels. The advent of the buffer gas cooling technique that permits to cool down atoms and molecules to cryogenic temperatures opens the door to go beyond the state of the art in terms of molecular complexity with the study of large and heavy molecules at relatively high frequencies (NIR,VIS). The objective of this PhD thesis is to present the design, the fabrication and the characterization of an instrument that will ultimately embody all these features, allowing for the study of large molecules in the gaseous phase in the near-infrared and visible regions of the light spectrum. In its final form, it will consist of a frequency comb as a light source, a FTS as a spectrum analyzer and a buffer gas cooling setup in order to perform the spectroscopy of cold molecules, the required sensitivity being achieved by making the measurements within an optical cavity., (SC - Sciences) -- UCL, 2022

Competence is one of the most successful survival strategies in bacteria. This powerful tactic synchronizes the production of antimicrobial compounds which eliminates competitors, providing genomic material availability for subsequent DNA uptake. Yet, competence regulation in streptococci is only partially understood. Particularly, the molecular mechanisms explaining how activation is restricted to a subpopulation (bimodality) and to a limited window of time (shut-off) are unknown. In this thesis, we aimed to decipher those complex mechanisms in the major commensal species Streptococcus salivarius. Combining molecular biology, biochemistry, microscopy and mathematical simulations, we unveil new regulatory pathways mastering ComRS, the major pheromone-pathway controlling competence in streptococci. In a first set of experiments, we show that the proportion of cells activating competence is directly linked to the concentration of the intracellular receptor ComR. We next demonstrate that this bimodal initiation requires a positive feedback loop on the pheromone comS, and identify the environmental sensor CovRS to control this process through comR regulation. We next describe a new degradation machinery of the pheromone controlled by competence activation, thereby ensuring ComRS shut-off. Finally, we uncover a link between bacterial cell-wall integrity and competence activation thanks to a genome-wide screen by CRISPR-interference. Altogether, those results help us understand how bacteria sense their environment and transmit it to complex regulatory pathways in order to produce collaborative and timed responses., (SC - Sciences) -- UCL, 2022

The Golgi apparatus is a major hub for post-translational modifications and for protein sorting. Accordingly, the preservation of Golgi structure and functionalities are everlasting tasks. It is ensured by mechanisms involving the control of luminal chemical composition and of lipid bilayer thickness, and is supported by structural and transport machineries at the cytosolic side of Golgi cisternae. Failings of those mechanisms usually lead to various cellular troubles, including glycosylation defects. In 2012, some congenital disorders of glycosylation were related to mutations of TMEM165 protein in human. As this protein was not characterized at that time, we started in our laboratory the study of Gdt1p, the Saccharomyces cerevisiae ortholog of TMEM165. It was demonstrated that Gdt1p is a Golgi-localized transmembrane protein able to transport Ca2+ and Mn2+ cations. Furthermore, GDT1 deletion is also characterized by Golgi trafficking defects and glycosylation troubles. The predicted topology of the protein matches with the usual topology of exchangers. In this study, we investigated two elements of Gdt1p physiological function, its transport mechanism and its regulation. Starting from the assumption that Gdt1p could exchange H+ ions against Ca2+ and Mn2+ cations across the Golgi membrane, we developed measurement strategies to assess it. A heterologous expression system using Lactococcus lactis was set up for direct H+ transport assay and a Golgi-localized pH sensor was developed for in vivo measurements in S. cerevisiae. Thanks to them, Gdt1p-mediated H+ transport activity was demonstrated. Then, we looked at Gdt1p regulation. We observed that Gdt1p is rapidly downregulated as a response to extracellular Mn2+ addition and that regulation occurs both at transcriptional and post-translational levels. The fast and efficient retrieval of Gdt1p from the Golgi membrane to be sorted to the vacuole probably occurs trough a novel degradation pathway., (SC - Sciences) -- UCL, 2022

In a context of decreasing water quantity and quality, the increasing use of different technologies helps to face water security threats such as such as economic growth, demography, and climate change. Seawater desalination technology is one of them. The treatment of seawater produces an additional supply of freshwater that can meet the growing demand. In some parts of the world, such as in Saudi Arabia, Israel or Singapore, desalinated water already constitutes more than half of the national water supply. Nevertheless, this technological fix also brings its lot of political, social, financial, and environmental challenges. This research produces a global picture of the impact of large-scale desalination on hydropolitics and transboundary water management. It focuses on the hydropolitical change this new source of non-natural water brings to the transboundary water cooperation table. It analyzes the impact large-scale desalination technology has on transboundary water interactions or international water exchanges. While studies on the impact of desalination exist, they often focus on the local level. The specific contribution of this research lies in the production of a thorough analysis of several case studies at the international level. The first objective is to analyze data before and after large-scale desalination to observe if there is an increase in cooperative events or not after the introduction of the technology. The second objective is to process and locate water interactions vis-à-vis the geopolitical context while applying common terms such as water security and the hydropolitical security complex. Finally, a third objective is to analyze the discourse of experts on the topic of water security, hydropolitics, and desalination to highlight relevant factors of large- scale desalination and effective transboundary water management. This study fills an existing gap in the water security and desalination nexus while laying the foundations for further research, (POLS - Sciences politiques et sociales) -- UCL, 2022

La thèse de doctorat porte sur les organisations de la fonction exécutive en Équateur, pendant les trois mandats présidentiels de Rafael Correa (2007-2017), dans le contexte du virage à gauche en Amérique latine. A ce propos, deux questions ont été posées: Comment la structure de la fonction exécutive en Équateur a-t-elle changé au cours de cette période ? Quelle combinaison de facteurs explique la permanence des changements politiquement importants dans la structure de la fonction exécutive ? Ces deux questions sont abordées à travers un design de recherche multiméthodes. La première phase comprend le recours aux techniques de codage ouvert et axial de la Théorie Ancrée pour l'analyse qualitative des textes normatifs, le traitement conceptuel des catégories émergentes et la description de la totalité des changements. Ensuite, la consultation aux experts via la méthode Delphi a été utilisée pour la sélection de cas. Finalement, la méthode de l'analyse qualitative comparée des ensembles flous (fsQCA) a permis d’identifier systématiquement les combinaisons de conditions qui expliquent la permanence du changement. Tout au long de la recherche, une variété de données a été exploitée, y compris des documents produits par les organisations publiques équatoriennes et des entretiens menés avec les acteurs politiques et administratifs responsables des processus., (POLS - Sciences politiques et sociales) -- UCL, 2022

Comment les discours publicitaires de la bière ont-ils évolué au cours des années dans la ville de Kinshasa ? Quelles raisons ont motivé la présence de certains discours sociaux dans les publicités de la bière ? Et comment certains sens ou significations le plus souvent conférés à la bière ont-ils émergé et évolué du début de la communication publicitaire jusqu’en 2014 ? Telles sont les questions auxquelles cette étude tente de répondre. Les textes publicitaires, depuis la première campagne de communication à Kinshasa dans les années 1980 jusqu’en 2014, constituent le corpus étudié. Ce corpus est complété par des données tirées des entretiens avec certains membres des équipes marketing et commerciales de deux principales sociétés brassicoles locales et des agences de publicité en RD Congo qui les accompagnaient ou les accompagnent encore. Nous avons également pris en compte d’autres données scientifiques renseignant sur la culture kinoise et des productions culturelles médiatiques qui reprennent certains faits de société, des thèmes, des figures et des éléments sémiotiques également repérés dans les textes des publicités de bière. Nous nous sommes intéressés à la publicité des bières, car elle est omniprésente en RDC et dans la ville de Kinshasa, où les discours des marques pénètrent le quotidien des Kinois. Le choix des publicités de la bière Primus et la bière Skol, deux bières qui ont accompagné les Congolais dans plusieurs grands évènements de leur histoire, nous a offert la possibilité de remettre ensemble tous les éléments culturels de la RD Congo et a permis une entrée privilégiée dans la compréhension de la culture congolaise. Les analyses systématiques de textes publicitaires de la bière Primus et la bière Skol nous ont révélé que le bonheur, la réussite de la vie, l’ambiance et le plaisir sont les valeurs principales et les significations basiques des messages que les brasseurs transmettent aux consommateurs de leurs bières. Cependant, ces valeurs basiques, (COMU - Information et communication) -- UCL, 2022

The Andean region is susceptible to soil erosion due to steep topography, prevalent rainfall and high probability of earthquakes and landslides. By its impressive length, continuity and height, the mountain ridges significantly disrupt the atmospheric circulation resulting in a wide variety of environmental conditions. The western flank draining to the Pacific Ocean is characterized by strong environmental gradients, rough topography with deeply incised canyons, and highly variable and extreme precipitation patterns. These environmental conditions pose particular challenges for erosion and sediment flux monitoring. The thesis presents new data on the sediment yield of Andean rivers draining to the Peruvian coast. The dataset is based on time series of river suspended load, discharge and turbidity, and sediment accumulation in reservoirs. About 55% of the observed variance can be explained by hydrometeorology and topography, while anthropogenic factors such as land use marginally improve the model predictions. The effect of climate variability on sediment transport was further studied in the Cañete catchment where the 240MW El Platanal hydropower plant is located. By calibrating a coupled hydrological-sediment transport model for the Cañete River, the effect of precipitation variability on sediment transport and reservoir sedimentation was assessed. Even under the most optimistic scenario, the lifespan of the reservoir is shorter that its officially expected functionality of 50 years. The geomorphic processes driving sediment production and transport were quantified using UAV-PPK-SfM techniques. The processing chain was optimized for 4D geomorphic monitoring in rough terrain by including co-registration techniques. By analyzing the spatial patterns in sediment yield along the western Andes, the thesis enhanced the knowledge base on sediment transport to the Peruvian coastal plain. Besides, it illustrated the vulnerability of hydroelectric facilities to climate variab, (SC - Sciences) -- UCL, 2022

Nowadays, life expectancy is increasing but is not systematically accompanied by a decent quality of life during aging. With the overall aging of the population, it is urgent to highlight strategies to promote the maintenance of autonomy at old age. While the effects of exercise training on limiting the loss of functional autonomy in the elderly are well-established, the molecular mechanisms by which it may slowdown the hallmarks of skeletal muscle aging, notably through the regulation of telomere health and cellular senescence, need to be further investigated. In this thesis, we found that even if endurance training did not effectively reduce senescence, the training status might attenuate the senescence-associated secretory phenotype in human skeletal muscle. Moreover, the age-dependent increase in TERRA expression might represent a novel biological marker of aging which is alleviated by endurance training., (MOTR - Sciences de la motricité) -- UCL, 2022

N-Salicylideneaniline (also called anil) is a compound which exhibits photochromism (reversible color change induced by light) in the solid-state. Such a feature is quite rare and requires in-deep studies to fully understand it, especially because it can be quite useful in many industrial applications such as secured inks (for banknotes for instance), screens or even optical data storage. Within this thesis, N-Salicylideneaniline and many of its derivatives (the “anils”) were studied in the scope of crystal engineering in order to establish a structure-property relationship and to improve its properties. More specifically, cocrystals were researched and studied using small organic molecules (such as carboxylic acids, amides, amines, benzene halides) as coformers. This resulted in the identification of about 100 cocrystals through the use of X-ray powder diffraction (XRPD), single crystal X-ray diffraction (SC-XRD), diffuse reflectance spectroscopy (DRS), thermal analysis such as thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) along with a few other methods such as Raman spectroscopy. The amount of collected data allowed to show a correlation between the number of intermolecular interactions involving the “moving moiety” of the anils and the presence of photochromism. We also present here a new approach of the Diffuse Reflectance Spectroscopy data treatment, which allows a better classification of the photochromic properties and also allowed the discovery of “weakly” photochromic compounds. These results encourage a revision of the old-empirical “dihedral angle rule” especially because a link between the intensity of photochromism and the torsion angle has been observed in this work. In the last part, we focused on cocrystals containing 2 different anils (instead of one anil and one coformer) and this allowed to observe the existence of a complex multi-phases binary diagram in the case of N-Salicylideneaniline/ N-Salicylidene-4-fluoroanil, (SC - Sciences) -- UCL, 2022

This dissertation studies the role of the EU in three environmental forums: the Convention on Biological Diversity (CBD), the Basel, Rotterdam and Stockholm (BRS) Conventions and the United Nations Environmental Assembly (UNEA). The project focuses on three dimensions of that role: the ambition of the EU’s positions in terms of environmental protection, the diplomatic activities conducted by the EU, and the influence of the EU on the outcome of the negotiations. It answers the following research question: What role does the EU have in international environmental negotiations and how can variation in this role be explained? The overall research question is addressed in two parts, applying a mixed-method design. I combine one quantitative with several qualitative measures. The first part focuses on developing a typology of roles and mapping the EU’s roles. The second part of the dissertation explains the EU’s ambition, diplomatic activity and influence. Taken together, the two parts of this dissertation make several contributions to the literature. Empirically, this dissertation shows that the EU is a reformist leader in environmental negotiations which usually defends ambitious positions, is diplomatically active and appears influential. This observation holds true in all three environmental forums. Theoretically, this dissertation provides novel insights into role theory. Contrary to the general assumption of role theory that ego and alter perceptions would differ, my research does not identify substantial differences between the two perspectives., (POLS - Sciences politiques et sociales) -- UCL, 2022

This thesis contributes to two fields of macroeconomics. The first two chapters contribute to the literature that investigates the role of household heterogeneity, in terms of marginal propensity to consume and labor income, for the ‘optimal’ design of fiscal policies. The first chapter explores how the introduction of household heterogeneity alters the prescriptions derived from the standard optimal fiscal policy framework that only accounts for a representative agent. When heterogeneity is accounted for the government uses taxation and transfers as a redistributing device that only partially corrects for fluctuations in income inequality. The second chapter builds on the results of the first. It develops a quantitative model that is estimated with US data on income and consumption dispersion among households. The model is then used to assess the relevance of the actual US fiscal policy. Unexpectedly, it concludes that the US fiscal policy is close to optimal. The third chapter contributes to the literature that is at the crossroad of the fields of history of macroeconomics and of macroeconomic pedagogy. It aims at reflecting on the theory used in the first two chapters of the thesis and in the teaching of macroeconomics. It identifies and discuss the deep methodological discrepancy between the theory used in research and graduate macroeconomics courses, on the one hand, and in undergraduate macroeconomic courses, in the other hand., (ECGE - Sciences économiques et de gestion) -- UCL, 2022

Metal-organic frameworks (MOFs) are porous coordination tri-dimensional assemblies with potential use for many applications, and especially in catalysis, gas storage and adsorption from solution. The work presented in this thesis mainly aims at improving the sustainable production of MOFs containing trimesate linkers, with well-characterized structures, as well as at the introduction of new types of active sites, under the form of second (“exotic”) metals, amine functions and defects, by easy to implement synthetic approaches. The main part of this thesis concerns the development of a new green aqueous strategy for obtaining the mesoporous MOF MIL 100(Fe) through the use of alkali trimesate salts and the investigation of the MOF’s formation mechanism. This synthetic strategy was further developed to allow incorporation of a second metal to obtain bimetallic MIL 100(Fe,M) incorporating transition, p-bloc and rare-earth elements as secondary metals in a one-pot fashion. The functionalization of mono- and bimetallic Al- and Fe-based MIL 100 MOFs with ethylenediamine (EN) was also investigated, including the CO2 adsorption performances and possibility to post-functionalize the obtained materials. Synthetic efforts were also made to improve the sustainability of the synthesis of lanthanide-based MOF 76 metal-organic frameworks, and increasing their stability towards water by linker modification. Finally, the synthesis of a new type of TiIII-based MOF, NH2 MIL 101(TiIII), was achieved, and the introduction of structural defects induced by mechanosynthesis was studied on HKUST 1 as model MOF. The new materials obtained in this work may find use in multiple applications, such as catalysis and gas sorption., (SC - Sciences) -- UCL, 2022

Internet access is still unavailable to one-third of the world population due to the lack of infrastructure, high cost, and the digital divide. Many access-limited communities opt for shared Internet access to build common network infrastructures to mitigate the cost. Internet connectivity in such infrastructures is typically provided by several limited, sometimes non-dedicated, gateways. Client nodes, i.e., the end-user hosts, use one gateway and switch to another when the first fails. In this scheme, the gateway configuration is done manually on the end-user side. This form of Internet connectivity is widespread and has the advantage that no central control is required, but it is also unreliable and inefficient due to several factors, such as unbalanced traffic load across the gateways. The thesis proposes that the network would benefit from a gateway selection mechanism that can provide good connectivity to the client nodes, balanced load distribution, and a dynamic adaptation to the current network state. However, providing such a dynamic gateway selection is complicated: since the performance of the gateways as perceived by the client nodes changes frequently and might depend on the location of the latter in the network, and optimal selection would require the continuous monitoring of the gateway performance by the client node. The cost of such network-wide performance monitoring is high in large-scale networks and would outweigh the benefits of the dynamic gateway selection. The thesis aims to design a low-cost distributed mechanism that provides an efficient and dynamic gateway selection while considering the overall balanced gateway selection distribution. ​ We presented the Sense-Share-Select framework, a distributed, collaborative Internet gateway selection framework designed for large-scale networks. We integrated the Power of Two Choices randomized load balancing algorithm with our close neighbors' collaborative performance monitoring algorithm to reduce, (SC - Sciences) -- UCL, 2022

Batteries are recognized as one of the most important energy storage systems due to their high energy density. As one of the most promising next-generation high energy density storage devices, lithium metal batteries have reached momentum. However, the use of lithium metal meets many technical problems with conventional liquid electrolytes, which can be solved by using solid-state electrolytes. Solid-state electrolytes are thus a key component of all-solid-state lithium metal batteries, and their progress directly affects the industrialization of all-solid-state lithium metal batteries. The current research on solid-state electrolytes focuses on two major types of materials: polymers electrolytes and inorganic electrolytes. Polymer electrolytes are a promising class of materials due to their easy processing, lightweight, flexibility, and they provide a feasible solution to safety issues. In this thesis, we introduce phosphonate-containing polymers in polymer electrolytes. Those are very promising compounds because of their good thermal stability, their ability to bind to metals, and excellent flame retardancy. Those novel phosphonate-containing polymers used in polymer electrolytes could maintain the electrolyte-electrode contact interface, prevent the growth of lithium dendrites, increase the electrochemistry stability window, and improve battery safety because of fire-retardant property. This opens the possibility to safely apply Li-metal as a high-capacity anode, which could provide a valuable strategy towards high-performance all-solid-state lithium metal batteries., (SC - Sciences) -- UCL, 2022

Tumors reprogram metabolic pathways to support the bioenergetic, biosynthetic, and redox needs of malignant cells. There is an increasing recognition that the tumor microenvironment drives many of these alterations in the metabolic phenotype of tumor cells, thereby paving the way for the development of specific anticancer metabolism-targeting compounds. In this thesis, we designed and synthesized such inhibitors, including some in the form of prodrugs to be activated in response to the acidic or hypoxic tumor microenvironment. In the first chapter, we designed and synthesized carboxyamidotriazole analogues to inhibit mitochondrial complex I of the oxidative phosphorylation (OXPHOS) pathway. In vitro cellular studies were conducted to evaluate their pharmacological activities, and preliminary structure-activity relationship analysis was obtained. Promising complex I inhibitors were further validated in 3D tumor spheroids. In the second chapter, we designed a pH-sensitive drug delivery system by conjugating a pH-dependent peptide with lipid metabolism-targeting drugs including Etomoxir (CPT1 inhibitor) and T863 (DGAT1 inhibitor), targeting mitochondrial fatty acylCoA uptake and the last step of triglyceride synthesis, respectively. Efficacy was evaluated using liposome models and in vitro cellular assays. In the third chapter, we designed and synthesized hypoxia-activated prodrugs (HAPs). Among the drugs that were modified to be specifically activated under low pO2 upon reduction of a nitro moiety (Part A), we considered COX inhibitor diclofenac repurposed recently as an inhibitor of lactate transport through MCT4 and a traditional antitumor drug tetrandrine. In Part B, a novel HAP model containing a triazene group was designed and synthesized. Mechanisms of triazene probe release by chemical reduction were studied to further gain insights on the potential use of these HAP in tumors. Altogether, the data obtained in this thesis support the feasibility of targeting pec, (SC - Sciences) -- UCL, 2022

The mutual neutralization reaction A⁺ + B⁻ → A⁰ + B⁰ plays an important role whenever an anion populated plasma is involved (interstellar molecular clouds, ionospheres, stellar atmospheres, etc.), and modifies its radiative emissions which are used for estimating stars metallicity. Additionally, the measurement of mutual neutralization can serve as a benchmark for the numerical models estimating the inelastic collisions used in these models of reaction dynamics. In this manuscript, we present results for several low energy mutual neutralization reactions measured with the UCLouvain single pass merged beam apparatus: He⁺/Li⁺ + H⁻/D⁻, C⁺/N⁺/O⁺ + D⁻/C⁻/O⁻/Si⁻/P⁻/S⁻, Na⁺ + O⁻/S⁻, and Ne⁺ + C⁻/O⁻/S⁻. We detail how a pair of time and position sensitive detectors allows us to obtain accurate branching ratios and partial differential cross sections. In order to rationalize the branching ratios we have measured, we developed a multi-channel Landau-Zener model combined with an updated version of the anion centered asymptotic (analytical) model (ACAM). The overall agreement between theory and experiment allows us to use this model to describe the mutual neutralization process. The ACAM validity domain is also studied, revealing additional processes responsible for the discrepancies between theory and experiment, such as the production of Rydberg series of the neutral atoms. The differential cross section was also computed using two models: the interrupted Rutherford scattering model and the impact parameter method. The former is analytical and describes well the collision energy dependency of the differential cross section while the latter gives quantitative results. It is also shown how differential cross section analysis provides a better insight into the mutual neutralization process, e.g. which molecular states are temporarily populated. As a conclusion, this manuscript suggests several ideas for improving both the theoretical models and the experimental setup., (SC - Sciences) -- UCL, 2022

Transposons are mobile genetic elements that are able to move from one position to another within genomes. Little is known regarding the mechanisms whereby transposons choose their target and communicate with host cellular machineries to convert transposition intermediates into products. In this thesis, we addressed this issue by using the bacterial transposon Tn4430 belonging to the Tn3-family of replicative transposons. The recently proposed ‘Replication Hijacking’ model for replicative transposition suggests that Tn4430 targets DNA replication or repair intermediates as a direct mechanism to recruit the host replication machinery during transposition. To deepen our understanding of this mechanism, we studied the functional and physical interaction between Tn4430 transposition complex and the replication machinery by using a combination of genetic, cellular and bio-informatics approaches. We first demonstrated that the transposon targets arrested replication forks in the host chromosome, providing strong evidences of an interaction between transposition and replication machineries. We then investigated Tn4430’s preference for small multi-copy plasmids instead of the chromosome or large conjugative plasmids. We also showed the influence of spatial and genetic environments on target site selection and on the efficiency of transposition. Finally, we developed a set of tools to study the physical interaction between the transposition complex and the replication machinery in living cells. Together, these results helped us understand the particular patterns of target site selection that optimize the element-host relationship and facilitate successful integration in the target., (SC - Sciences) -- UCL, 2022

The importance of tropical forests in the global climate system is widely known. Through their high productivity they represent a significant global carbon reservoir. Preserving this function needs a continuous supply of nutrients, mainly nitrogen (N) and phosphorus (P). However, the availability and biogeochemical cycling of these nutrients is highly variable in space and time and the understanding of different nutrient loss pathways is still lacking. The influence of soil erosion on the availability of these nutrients in pristine forests of the tropics is not well understood. To gain a better mechanistic understanding of the aquatic loss processes of N and P, we monitored different headwater streams in three distinct tropical forests of the Congo Basin and determined the influence of soil erosion on soil N. This knowledge is important to assess the response of these ecosystems to changing climate and land use. To assess the importance of soil erosion in tropical forests and export of sediments and nutrients from drainage basins, the first part of the thesis focussed on the fundamental understanding of the dynamics and drivers of sediment export in headwater streams of a tropical lowland forest and a deciduous Miombo woodland. We used high temporal resolution turbidity data and analysed the turbidity-discharge hysteresis patterns during storm events. Although these forest systems are situated in very old and stable landscapes, the obtained sediment yields were substantial and comparable to forests in more geomorphic active sites of the tropics. Although the Miombo only experiences a five-month wet season, similar annual sediment export was found as for the lowland forest, due to the lower vegetation cover. Furthermore, results showed that storm events exported 30% and 68% of the annual sediment yield in the lowland and the Miombo, respectively. In Chapter three, it was shown that soil erosion and storm events also play a crucial role in aquatic nutrient export from, (SC - Sciences) -- UCL, 2022

Modelling soil erosion is hampered by the complexity intrinsic to the short-term variability and dynamics between its physical properties. Soil crust development, in particular, is one of the most important factors controlling runoff and erosion, but its properties are difficult to assess. Accurate and spatially distributed data, particularly at fine scale, are increasing in demand by the scientific community to tackle this issue. Remote sensing with multispectral imaging could meet this demand, but a series of issues related to its signal complexity must be solved to provide qualitative data. This thesis focused on the detection capability of the development dynamics of soil physical crust. The general objective was to understand whether soil physical crust development could be detected and modelled by means of multispectral remote sensing, using low-altitude uncrewed aerial vehicles (UAS), with a case study on loamy soils of the Belgian loess belt. After an assessment of spectral sensor technology and analytical methods, this thesis proposed an innovative methodology to model soil physical crust development, as defined by the spectral changes caused on the soil by cumulative amounts of rainfall kinetic energy. This was achieved by developing a data processing protocol for multispectral imaging in the visible and near-infrared range. By validating the laboratory methodology in real field conditions, the results offered some evidence that it is possible to map the development of soil physical crust with a remote sensing application. The last part of this thesis tackled a critical issue with the negative effects of soil anisotropy on multispectral imaging, proposing a semi-empirical correction methodology with good preliminary results, and easing the way for wide scale UAS-based assessment of soil properties with multispectral imaging., (SC - Sciences) -- UCL, 2022

Endocytosis is an essential cellular process required for the uptake of nutrients from the cell environment and the turnover of plasma membrane components(commonly referred as “cargoes”). It regulates fundamental cellular functions as diverse as cell signaling, adhesion, migration, polarity, division, growth or differentiation. In particular, mammalian cells have developed multiple endocytic routes/mechanisms to support the vast array of physiological conditions, functions and cargoes they face. However, while several endocytic mechanisms have been described so far, their biological relevance often remains elusive, especially in pathophysiological contexts such as cancer. In 2016, my lab identified a cell surface cargo whose internalization seemed to rely on a yet to characterize endocytic route: the protein CD166/ALCAM(Activated Leukocyte Cell Adhesion Molecule). CD166 is an immunoglobulin-like protein involved in cell adhesion and migration, which has been linked to cancer progression by numerous studies. This protein has notably received particular attention as a promising target for new immunotherapies. However, virtually nothing was known about its cellular trafficking. In that context, the present thesis aimed at unveiling the molecular machinery that underlies CD166 internalization and that modulates its function at cancer cell surface. Using state-of-the-art microscopy and cell biology techniques, we could show that CD166 is a clathrin- and dynamin-independent cargo internalized via a novel endocytic mechanism that involves the BAR domain protein endophilin-A3 and the extracellular lectin galectin-8. Additionally, we could demonstrate that the actin cytoskeleton and its regulatory GTPase Rac1 dynamically associate with CD166-positive endocytic carriers and that their perturbation strongly inhibits the uptake process. We also provide evidence that microtubules and kinesin molecular motors are required to potentiate the endoA3-dependent endocytosis of CD166. F, (SC - Sciences) -- UCL, 2022

Aquaporins (AQPs) are channels present in all living organisms. They share the hour-glass shape and are involved in many cellular processes. Plasma membrane intrinsic proteins (PIPs) are AQPs responsible for the facilitated diffusion of water and small solutes through plasma membrane (PM). Land plant PIP subfamily is composed of two distinguishable phylogenetic clusters: PIP1 and PIP2. They assemble as homo- or heterotetramers, the monomer being the functional unit. Previous works have demonstrated that PIPs present a dissimilar behavior regarding their subcellular localization and function. PIP2s are considered as efficient water channels and they localize in the PM. On the other hand, when expressed alone, most of the PIP1s are retained in the endoplasmic reticulum (ER) and are not efficient water channels. When co-expressed, PIP1s and PIP2s interact, a process leading to the relocalization of PIP1s from the ER to the PM and to an increase in the cell water permeability. In maize, this synergistic effect was observed for most of ZmPIP1s members, including ZmPIP1;2 when co-expressed with ZmPIP2;5. This unexpected synergy together with localization studies led researchers to further investigate the nature of ZmPIP1 and ZmPIP2 interaction. The heterotetramerization of PIP monomers is the mechanism responsible for the ZmPIP1 trafficking to the PM and for the modulation of the cell membrane permeability. ZmPIP1;1 is a ubiquitous and one of the highest expressed AQP in maize. It is the closest paralog of ZmPIP1;2. Despite their striking similarity, their function does not correlate. Previous studies showed that the co-expression of ZmPIP1;1 with ZmPIP2;5 did not lead to a synergistic effect in oocyte membrane water permeability, while both isoforms were physically interacting and found in the PM. This enigmatic isoform has been considered to be an inactive water channel until nowadays. In this thesis, we aimed at unraveling the role of ZmPIP1;1, using heterologous and h, (SC - Sciences) -- UCL, 2022

Modern societies are facing a drastic demographic increase that induces economic and ecological concerns. Alternatives from fossil fuels are required to respond to the energy and chemicals demand while keeping pollution at the lowest possible level. One of the most promising solution is the use of lignocellulosic biomass to produce chemicals and fuels. Lignocellulosic biomass is a non-edible renewable source that is composed of cellulose, hemi-cellulose and lignin. These three components can be valorized into high-value molecules. Among all the possibilities, sorbitol production from cellulose is a very attractive topic and the subject of this PhD thesis. This transformation occurs in two steps: hydrolysis of cellulose into glucose followed by hydrogenation. In this context, bifunctional catalysts that can enhance both steps at the same time, to improve sorbitol production, have been developed. Firstly, catalysts composed of Ru nanoparticles deposited on carbon supports have been investigated for hydrogenation of glucose into sorbitol. Secondly, incorporation of nitrogen within the carbon materials lattice has been studied for enhancing Ru hydrogenation activity. Thirdly, the hydrolysis of cellobiose (model molecule for cellulose) into glucose has been improved by increasing the acidity of carbon materials through the addition of sulfonic functions using a diazonium coupling method. Finally, bifunctional catalysts combining benefits from both the Ru nanoparticles and the sulfonic functions on the carbon materials have been synthesized for producing sorbitol from cellobiose and ultimately directly from cellulose, competitively when compared to alternatives proposed in the literature., (SC - Sciences) -- UCL, 2022

Negative interest rates have significantly impacted multiple segments of financial markets and market participants' investment behavior. With nominal interest rates entering negative territory for the first time in history, a reassessment of the existing framework for interest rate modelling and derivative pricing is warranted. Moreover, lower bond yields induce investors to seek higher returns in other asset classes which are potentially associated with higher risks. Therefore, priority should be given to the development of new modelling solutions for the real-time monitoring of financial market volatility, correlation, and liquidity conditions given their central role in portfolio allocation and risk management. This dissertation revolves around the development of modelling approaches with relevant applications to financial markets. In particular, Chapter 1 studies the implications of the negative interest rate environment for the modelling of short rates and the pricing of interest rate derivatives. In addition, we propose a model calibration approach that takes into account the whole implied forward rate distribution rather than sparse data points for derivative prices or implied volatilities. Chapter 2 focuses on the development of a Dynamic Conditional Score (DCS) model for the log correlation matrix which can accommodate fat tails in the conditional distributions and generalizes the Beta-t-EGARCH model of Harvey (2013), which uses the student-t distribution, to the multivariate case. In Chapter 3, we develop a new algorithm for dynamic portfolio selection which combines a Dynamic Conditional Correlation (DCC) model with nonlinear shrinkage for the dynamics of asset returns with LASSO-type penalization schemes to control for within- and between-group variations in portfolio weights. In the application, we consider US stocks whose sectoral classification is used for group assignment. Other applications could also be considered. For instance, this framework coul, (SC - Sciences) -- UCL, 2022

Since many years, chemists leveraged the photophysical properties inherent to ruthenium or iridium-based photosensitizers to develop strategies towards conversion of sunlight into chemical energy such as molecular hydrogen or complex organic molecules. However, the scarcity and toxicity of these elements prevent the potential scalability of this kind of system. This is why the development of efficient photocatalytic complexes using cheap and abundant first row metals would offer an important solution to this problem. Due to its abundance in the earth’s crush, the iron element seems perfect to supplant its ruthenium analogue. Nonetheless, the Fe(II)-based polypyridyl photosensitizers suffer from their intrinsic photophysical properties that deactivate non-radiatively the low-lying excited-state and hence reduce its lifetime. Important insights were recently brought by Wärnmark et al. in the conception of Fe(II) and Fe(III)-based photosensitizers through ligand modifications strategy. During this Ph.D. thesis, we have designed and synthesized novel iron-based photosensitizers. Through coordination sphere modifications, we attempted to tune their photophysical properties and then utilized them as potent photosensitizer in photoredox catalysis. By careful investigations, we were able to determine the key parameters that could potential govern a photoreaction and to propose an in-depth reaction mechanism through time-resolved ultrafast spectroscopic techniques., (SC - Sciences) -- UCL, 2022

Torsion theories were originally introduced by D. Dickson to study abelian categories, and in particular categories of modules over rings. More recently torsion theories have been studied in many different non-abelian settings, with different applications in homological algebra. The objective of this thesis is to apply some techniques of torsion theories and preradicals, well known in the abelian context, to the semi-abelian category of simplicial groups. First, we introduce a family of examples of torsion theories in simplicial groups which are defined by simplicial groups with a trivial Moore complex below or above a certain degree. These examples extend the examples of torsion theories in internal groupoids in groups in a natural way. Moreover, we prove that the category of internal groupoids in groups is itself a torsion-free subcategory of simplicial groups. We observe that these torsion theories constitute a linearly ordered lattice, and from the relations between the homotopy groups and the homology of the Moore complex, we can study the homotopy groups of a simplicial group as suitable quotients of torsion subobjects. Since simplicial groups can be studied through their Moore complexes with operations, we find easier descriptions of torsion theories in certain subcategories of simplicial groups. In particular, we consider torsion theories in D. Conduché’s 2-crossed modules and N. Ashley’s reduced crossed complexes which expand on the known examples of torsion theories in the category of crossed modules., (SC - Sciences) -- UCL, 2022

Carotenoids are secondary plant metabolites with antioxidant and anti-inflammatory properties. Some can be converted into vitamin-A. Their dietary intake and tissue concentrations have been related to the reduced incidence of several chronic diseases. Due to their low water solubility requiring emulsification prior to absorption, carotenoids are of low and varying bioavailability. While dietary fiber, lipids, and minerals were shown to influence the solubilization of carotenoids, a prerequisite for their bioavailability, the interactions between proteins and carotenoids during gastro-intestinal (GI) digestion have, to our knowledge, never been studied systematically. The purpose of the PhD thesis was thus to study interactions of carotenoids and frequently consumed proteins during digestion that could impact aspects of carotenoid bioavailability. Preceding a confirmatory human trial, in vitro studies were conducted, by means of GI digestion coupled to Caco-2 cellular uptake models to investigate bioaccessibility and cellular uptake, respectively. When investigating effects of whey and soy protein isolate (WPI, SPI), gelatin and sodium caseinate on individual carotenoids, carotene bioaccessibility increased by almost 2-fold, while xanthophylls were reduced in their bioaccessibility to about half. Similarly, for real food matrices, bioaccessibility and uptake were more enhanced for apolar carotenes vs. xanthophylls. In the human trial, WPI improved by about 1/3 the bioavailability of carotenoids from the tomato/carrot juice, while SPI had a borderline negative effect, confirming in vitro results. These findings may aid consumers in choosing meal compositions, especially persons relying on carotenoids for meeting vitamin A requirements, such as vegetarians, or those living in areas with low available pre-formed vitamin A. The results may also be interesting for food/supplement producers, offering insights into formulations that assure high carotenoid bioavailability., (AGRO - Sciences agronomiques et ingénierie biologique) -- UCL, 2022

Le point de départ de cette monographie est Kunturi, une communauté rurale du département de Cochabamba en Bolivie. Nous y suivons ses habitants dans leurs mobilités entre campagne et ville. Leurs déplacements et installations dans de nouveaux espaces de vie sont envisagés comme un processus: celui de « s’habituer ». A partir de ce terme émique, la thèse décrit les processus d’habituation et de déshabituation qui sont à l’œuvre dans les quotidiens des habitants de Kunturi. Elle aborde le passage entre la campagne et la ville comme des déplacements à la fois géographiques mais aussi culturels et psychiques. En effet, la Bolivie n’échappe pas à la tendance mondiale qui tend à l’urbanisation et à la dépaysanisation de sa population. Si la mobilité et les échanges entre différents espaces sont inhérents aux organisations paysannes du pays depuis des siècles, un mouvement d’installation vers les villes est à l’oeuvre depuis les années 1950. Il s’est nettement accéléré à la fin du vingtième siècle. Résultat, depuis une quinzaines d’années, la dynamique entre campagne et ville a pris un nouveau tournant. Il est dû notamment à la construction de nouvelles infrastructures routières, au déploiement des technologies de télécommunication, mais aussi à l’arrivée d’Evo Morales au pouvoir qui a marqué un changement symbolique fort pour les populations rurales et indigènes historiquement marginalisées dans l’espace urbain. Au-delà du niveau micro de l’ethnographie, la thèse donne à penser plus largement les processus d’urbanisation et de dépaysanisation qui s’opèrent au sein du pays. Elle réfléchit les changements socio-culturels, les places nouvelles données et prises, par les populations d’origines indigènes et rurales, dans les villes., (POLS - Sciences politiques et sociales) -- UCL, 2022

In this thesis, I give voice to children of separated parents who are in shared physical custody to understand how they appropriate their multilocal lifestyle and how they define and construct a sense of home while living in more than one place. Living in and between different places of residence implies that young people face obstacles and difficulties in their daily lives - such as the physical burden of carrying their personal belongings, the emotional lack of a parent during days of absence, the distance the commute between homes, juggling different and even contradictory family cultures, etc. However, I hypothesize that by being socialized in this particular environment, children potentially develop skills, strategies and ways of being and doing specific to this multilocal lifestyle that enable them to cope with these periods of absence and presence. More specifically, I question how space has an impact on the construction of family relationships for 'multilocal children' and, conversely, the impact that these relationships have on the construction of space as well. Thus, I examine how space and family relationships influence and structure each other. Depending on family relations and, more particularly, on the feeling of belonging to the family (through family practices), on the negotiated place given to the child, and the quality of relations maintained with the other people who share the same space, I analyze how the child will inhabit, invest and appropriate certain rooms, certain spaces, certain objects rather than others (his or her room, his or her neighborhood, his or her garden, his or her suitcase, a parent's car, etc.) and feel more or less at home there. In the same way, I study the way in which the child's ways of dealing with space influence the creation, maintenance and quality of his or her family relationships. I show that these spatial and family practices integrate the different spaces of residence that were envisaged as distinct from each ot, Dans cette thèse, je donne la parole aux enfants de parents séparés qui alternent les lieux de résidence pour comprendre la manière dont ils s’approprient leur mode de vie en alternance et comment ils définissent et construisent un sens du chez-soi en habitant dans plus d’un lieu d’habitation. Le fait de vivre dans et entre des lieux de résidence distincts implique que les jeunes font face à des obstacles et des difficultés dans leur quotidien (comme le poids physique que représente le transport de leurs affaires personnelles, le manque affectif éprouvé à l’égard d’un parent pendant les jours d’absence, la distance à parcourir entre les domiciles, le fait de jongler entre des cultures familiales différentes voire contradictoires, etc.). Cependant, je pose l’hypothèse qu’en étant socialisés dans cet environnement particulier, les enfants développent potentiellement des compétences, des stratégies et des manières d’être et de faire spécifiques à ce mode de vie multilocal qui leur permettent de faire face à ces périodes d’absence et de présence. Plus spécifiquement, j’interroge, l’apport de l’espace dans la construction des relations familiales des “enfants multilocaux” et, à l’inverse, l’impact que ces relations ont sur la construction de l’espace. Ainsi, j’examine la manière dont l’espace et les relations familiales s’influencent et se structurent mutuellement. Dépendant de ses relations familiales et, plus particulièrement, du sentiment d’appartenance à la famille, par le biais des pratiques familiales, de la place négociée qui lui est accordée, de la qualité des relations entretenues avec les autres personnes qui partagent le même espace, j’analyse comment l’enfant va habiter, investir et s’approprier certaines pièces, certains espaces, certains objets plutôt que d’autres (sa chambre, son quartier, son jardin, sa valise, la voiture d’un parent, etc.) et s’y sentir plus ou moins chez lui. Tout comme à l’inverse, j’étudie la façon dont ses manières de faire avec de, (POLS - Sciences politiques et sociales) -- UCL, 2022

This doctoral research, in the field of information and communication sciences, focuses on the professional playful practices of primary school teachers who work in ordinary (i.e. non-specialised) education in the territory of the Wallonia-Brussels Federation, for all years and all educational networks. The current playful practices were studied in the framework of this research: the analogue, digital and hybrid media used by the teachers were considered. It has a double objective: to describe the playful practices of teachers and to understand these practices. A method divided into several phases, inductive and mixed, was thus implemented. However, this doctoral research is mainly qualitative, with the different approaches serving a case study. During the case study, nine teachers with diversified playful practices were followed during one school year. Based on the collected data, three perspectives were crossed on the practices of the teachers who constituted the "cases": the researcher's perspective on these practices, the teacher’s perspective on their own practices, and the perspective of their pupils, based on their experience in the classroom. These data were analysed along three lines, which structure the manuscript: a) "the game in our field", which aims to answer the questions "on what elements is the playful dimension of teaching practices based?" and "how is this playful dimension perceived by the pupils?" ; b) "the introduction of game into teaching practices", which focuses on the question "through what concrete actions do teachers give a playful dimension to their teaching content when planning and shaping it?" ; and c) "the experience of game in the classroom", which aims to answer the questions "how is game offered to pupils in the classroom?" and "what relationships does game induce between pupils and between teacher and pupils?". In order to propose solutions to the needs expressed by the participants in the case study, as well as to the obstacles, Cette recherche doctorale, inscrite en sciences de l'information et de la communication, porte sur les pratiques ludiques professionnelles des instituteurs et institutrices primaires qui exercent dans l'enseignement ordinaire (i.e. non spécialisé) sur le territoire de la Fédération Wallonie-Bruxelles, toutes années et tous réseaux d'enseignement confondus. Ce sont les pratiques ludiques actuelles qui ont été étudiées dans le cadre de cette recherche : tant les supports analogiques, numériques et hybrides mobilisés par les instituteurs y ont été considérés. Elle poursuit un double objectif : décrire les pratiques ludiques des instituteurs et comprendre ces pratiques. Une méthode découpée en plusieurs phases, inductive et mixte, a ainsi été mise en œuvre. Cette recherche doctorale est toutefois principalement qualitative, les différentes démarches étant au service d'une étude de cas. Lors de cette dernière, neuf enseignants et enseignantes ayant des pratiques ludiques diversifiées ont été suivis, ce durant une année scolaire. À partir des données recueillies, trois regards ont été croisés sur les pratiques des instituteurs ayant constitué les "cas" : celui que la chercheuse a posé sur leurs pratiques, le leur sur leurs propres pratiques et celui de leurs élèves, à partir de leur vécu en classe. Ces données ont été analysées suivant trois axes, qui structurent le manuscrit : a) "le jeu sur notre terrain", qui vise à répondre aux questions "sur quels éléments la dimension ludique des pratiques d'enseignement repose-elle ?" et "comment cette dimension ludique est-elle perçue par les élèves ?" ; b) "l'introduction du jeu dans les pratiques d'enseignement", centré sur la question "via quelles actions concrètes les instituteurs donnent-ils une dimension ludique à leurs contenus d'enseignement lorsqu'ils les planifient et les mettent en forme ?" ; et c) "l'expérience du jeu en classe", qui vise à répondre aux questions "comment le jeu est-il proposé aux élèves en classe ?" e, (COMU - Information et communication) -- UCL, 2022

This thesis deals with Beyond the Standard Model (BSM) scenarios with both displaced and prompt signature. For the displaced signature a Heavy Neutral Lepton analysis in the semileptonic final state is performed. I am looking for right-handed neutrinos with mass between 1 and 15 GeV. Those particles are accommodated in Majoran and Dirac hypothesis, exclusion limits on the mass and on the lepton-neutrino coupling are presented for both models. On the other hand, also BSM scenarios with prompt signature are investigated within the Higgs framework. A ttH multileptonic differential analysis is presented targeting both EFT results and SM unfolding results. Deep Neural Network is largely use for regression and to discriminate SM for EFT signature. Following the stream of investigating the Higgs properties a HH analysis in bb4l final state is presented. This analysis takes the advantage of a very clear signature and a small amount of background that maximise the sensitivity search, limits on the anomalous values of the Higgs trilinear coupling and on the SM hypothesis are shown. All these analyses target the full Run2 dataset of the CMS experiment, (SC - Sciences) -- UCL, 2022

In the shadow of the Wikipedia project and for a little over twenty-one years now, a virtually unknown social movement has been developing called Wikimedia. Its vision of the future is that of "a world in which every human being can freely take part in the sharing of all knowledge". Responsible for the Wikipedia project, but also for nearly a thousand websites, this movement brings together several hundred groups and associations around the world. It is also the only non-profit actor in the top 50 most visited websites in the world. In this sense, it appears today as the most visible manifestation of a counter-culture inherited from the pioneers of the Net and the free software movement which opposes today the commodification of the world by a handful of political and economic actors. In order to understand this movement, this research is part of a prospective anthropology that favors long-term participant observation, the laborious excavation of Web space and the production of detailed ethnographic analyses. When reading it, we discover the complexity of an organization that appeared within the digital ecumene and then developed offline. This organization ensures an economic, technical, political and epistemic management of life together, which was gradually put in place by millions of actors confronted with the tensions that arise from the opposition between volunteering and salaries, sharing and giving, freedom and control, consensus and elections, equality and hierarchy. An organization so original in fact, that it comes to question a set of well-established dogmas that prevent us from imagining the world freely. (Translated by deepl.com free option), Dans l’ombre du projet Wikipédia et depuis un peu plus de vingt-et-un ans déjà, s’est développé un mouvement social pratiquement inconnu que l'on nomme Wikimédia. Sa vision du futur est celle d' « un monde dans lequel chaque être humain peut librement prendre part au partage de la totalité des connaissances ». Responsable du projet Wikipédia, mais aussi de près d’un millier de sites web, ce mouvement rassemble plusieurs centaines de groupes et d’associations réparties dans le monde. Il est aussi le seul acteur à but non lucratif du top 50 des sites Web les plus fréquentés au monde. En ce sens, il apparait donc aujourd'hui comme la manifestation la plus visible d'une contre-culture héritée des pionniers du Net et du mouvement des logiciels libres qui s'oppose de nos jours à la marchandisation du monde par une poignée d'acteurs politiques et économiques. Pour appréhender ce mouvement, cette recherche s'inscrit dans le courant une anthropologie prospective propice à l'observation participante de longue durée, la fouille laborieuse de l'espace Web et la production d'analyses ethnographiques détaillées. À sa lecture, on y découvre toute la complexité d'une organisation apparue au sein de l'écoumène numérique pour se développer par la suite au niveau hors ligne. Celle-ci assure une gestion économique, technique, politique et épistémique, tout à fait originale du vivre ensemble, qui fut petit à petit mise en place par des millions d'acteurs confrontés aux tensions que suscite l'opposition entre bénévolat et salariat, partage et dons, liberté et contrôle, consensus et élections, égalité et hiérarchie. Une organisation tellement originale en fait, qu'elle en arrive à remettre en cause un ensemble de dogmes bien établis qui nous empêchent d'imaginer le monde librement., (POLS - Sciences politiques et sociales) -- UCL, 2022

After a stroke, around 80% of individuals suffer from upper limb motor impairments leading to an activity limitation and a reduced quality of life. To optimise rehabilitation and better predict recovery, it is recommended that patients be evaluated regularly. In this PhD thesis, different virtual applications allowing for the assessment of post-stroke manual dexterity, upper limb capacity and forearm kinematics have been validated. Results of these studies brought to light the potential of immersive virtual reality to deliver autonomous and objective assessments. Several meta-analyses were also conducted to assess the effect of virtual reality, robot-assisted therapy, serious games, self- and tele-rehabilitation programs in the treatment of individuals with stroke. Results of these works now open new perspectives for the use of technological means in the assessment and rehabilitation of individuals with stroke., (MOTR - Sciences de la motricité) -- UCL, 2022

Depuis son avènement et plus fortement à partir des années 90, l’Union européenne est tiraillée entre une volonté croissante d’implication dans le secteur de l’éducation et le principe de subsidiarité affirmant la primauté des États membres sur ce secteur sensible. N’ayant pas les moyens d’intervention - notamment législatifs - dont disposent ses États membres sur ce secteur, l’Union européenne a fait émerger des instruments de gouvernance se distinguant des processus politiques conventionnels. Parmi ces instruments se trouve la Méthode Ouverte de Coordination européenne en éducation, appelée cadre stratégique Éducation et Formation 2020. L’objectif de cette thèse est de comprendre comment à travers la MOC, le système politique se transforme lorsqu’il s’organise non plus au niveau de l’État-nation, mais bien au niveau européen. Pour analyser cette transformation, nous nous basons sur la théorie générale des systèmes sociaux de Niklas Luhmann et sur la mise en place d’une ethnographie du politique visant à observer la MOC « en action ». Nous proposons d’analyser la MOC comme un cycle politique alternatif, ne se basant pas sur la prise de décisions législatives, mais bien sur des mécanismes d’apprentissage ou de dissémination d’informations et de bonnes pratiques à propos des systèmes éducatifs européens. À travers cet emprunt de rationalités alternatives, notamment scientifiques, la MOC redéfinit ce que l’on entend par politique au niveau européen en élargissant les moyens d’action de l’UE. Ce faisant, la MOC renforce la globalisation du politique au-delà de l’État-nation., (POLS - Sciences politiques et sociales) -- UCL, 2022

The successive integration of the younger generations into the political body is important for the proper functioning of our democratic societies and the development of individuals’ sense of belonging to the wider community. However, in the last decades, various studies have raised concerns about the political disengagement of young people and have investigated the development of new, non-institutionalised or media-based forms of engagement. In the information and communication sciences, and specifically in the field of media literacy, studies postulate that media education could support active citizenship among young people. In particular, these studies seek to understand the influence of educational activities, and the media competences they develop, on the (actual or potential) civic participation of adolescents and young adults. In line with these studies, we wonder: What is the link between media literacy and civic engagement? In a distinctive way, we choose to focus on actual situations of civic engagement and seek to understand what role the media play in them. Our PhD thesis examines the link between young adults’ (25-30 years old) civic engagement within a self-organised group and their media literacy (considered from the perspective of practices). We mobilise a qualitative and comprehensive method, which combines mainly observations and interviews, to study two civic groups located in French-speaking Belgium, namely in Walloon Brabant (first fieldwork) and in Brussels Region (second fieldwork). The empirical work carried out in the first fieldwork enables us to describe the media practices of civically engaged young adults and to develop a better understanding of the Belgian French-speaking civic landscape. The second fieldwork enables us to understand the way these media practices are embedded in broader social practices, and to discover how the young adults studied integrate themselves into the civic group, invest time and energy in it, participate as in, L’intégration successive des jeunes générations au corps politique est importante, car elle permet le bon fonctionnement de nos sociétés démocratiques et le développement d’un sentiment d’appartenance des individus envers la communauté plus étendue. Cependant, ces dernières décennies, divers travaux scientifiques s’inquiètent du désengagement politique des jeunes, et s’intéressent au développement de nouvelles formes d’engagement, non-institutionnalisées ou médiatiques. En sciences de l’information et de la communication, et spécifiquement dans le champ de la littératie médiatique, des études postulent que l’éducation aux médias pourrait favoriser une citoyenneté active des jeunes. Ces études cherchent notamment à comprendre l’influence des activités éducatives, et des compétences médiatiques qu’elles développent, sur la participation civique (effective ou potentielle) des adolescent·e·s et des jeunes adultes. Dans la lignée de ces recherches, nous nous interrogeons : Quel est le lien entre la littératie médiatique et l’engagement civique ? De façon distinctive, nous choisissons de nous intéresser à des situations concrètes d’engagement civique et cherchons à comprendre le rôle que les médias y jouent. Notre thèse de doctorat porte sur le lien entre l’engagement civique de jeunes adultes (25-30 ans) au sein d’un groupe auto-organisé et leur littératie médiatique (envisagée sous l’angle des pratiques). Nous mobilisons une méthode qualitative et compréhensive, mêlant principalement des observations et des entretiens, afin d’étudier deux groupes civiques situés en Belgique francophone, dans le Brabant wallon (premier terrain) et en Région de Bruxelles-Capitale (second terrain). Le travail empirique réalisé au sein du premier terrain nous conduit à décrire les pratiques médiatiques de jeunes adultes engagé·e·s, et à mieux appréhender le paysage civique belge francophone. Le second terrain nous permet de comprendre la façon dont ces pratiques médiatiques s’insèrent dans, (COMU - Information et communication) -- UCL, 2022

Urbanization and agriculture are strongly modifying natural ecosystems and these land use changes are now considered as major drivers of biodiversity change. Yet, some species appear to be able to deal with human-created environments. However, because these settings show altered biotic and abiotic conditions, we may expect phenotypic adjustments as a response to a life in urban and agricultural areas. In this thesis, I studied personality differences between woodland, agricultural and urban populations of the speckled wood butterfly (Pararge aegeria), a former forest specialist that successfully colonised anthropogenic habitats. Using behavioural tests that quantify variation in boldness, activity and exploration, I show that butterflies from different landscapes of origin differed regarding mean levels of boldness and syndrome structure (i.e. the correlation between personality traits). As these experiments involved laboratory-reared individuals, results suggest a genetic basis to the observed differences. The conducted experiments also shed light on environmental conditions that affect personality traits through phenotypic plasticity, including age and intraspecific interactions (i.e. male-male fights). Additionally, I show that developmental conditions affect the repeatability of behavioural traits. Using different experimental approaches, I also tested the ecological relevance of personality traits in the speckled wood butterfly. While boldness does not correlate with aspects of spatial use, more active males were more likely to win territorial fights, which may give them a fitness advantage. Together, these results provide valuable insights into the field of invertebrate personality – a group that has been rather overlooked in the context of animal personality – and they contribute to understanding the response of species to human activities., (SC - Sciences) -- UCL, 2022

Over the last decade, the enormous amount of data gathered by the Large Hadron Collider (LHC) has put the Standard Model (SM) under severe testing, proving it the most successful theory in particle physics. Despite such success, the SM is an inherently incomplete theory. The current challenges facing the SM have led to the proposals that new physics must exist. This new physics beyond the SM may not be necessarily evident in the resonant production of new particles at the LHC. Therefore, the SM effective field theory approach (SMEFT) can be used as a framework to parameterise possible deviations from the SM due to the presence of such new states that otherwise can not be probed directly with the current reach of our colliders. One of many possible probes of new physics is top quark interactions. The motivation behind the vigorous effort put into probing top quark processes is its high mass and strong coupling to the Higgs boson. This thesis presents three SMEFT studies of different top quark processes at hadron colliders. Single top quark production associated with a WZ-bosons pair at next-to-leading-order (NLO) in QCD is non-trivial due to its overlap with other resonant processes at leading-order (LO). In the first study of the thesis, we employed diagram-removal methods to suppress the resonant overlap, and therefore, define tWZ at NLO in a suitably defined phase-space region in which SMEFT predictions can be reliably obtained. This study will allow the inclusion of the tWZ data in future global LHC studies. In the second study, we investigated the four top quark production considering all possible QCD and EW-induced amplitudes for all the relevant dimension-six SMEFT operators. We show that formally subleading terms give rise to significant cross-section contributions, providing sensitivity to a broader class of operators. Inclusive and differential predictions for the LHC and the FCC-hh were obtained. Furthermore, we carried out projection studies by which we s, (SC - Sciences) -- UCL, 2022

This dissertation is composed of three chapters investigating three different law dimensions and their connection with migration, economic growth, and the stock market. The first chapter evaluates the importance of access to justice (ATJ) for economic growth. We create a new database on the number of professional judges per 100,000 inhabitants by collecting data from various public institutions. We draw on these data as a macro-level proxy capturing the fundamental and historical evolution of ATJ from 1970 to 2014 for a wide range of developed and developing countries. Using an instrumental variable approach in a dynamic panel setting to deal with endogeneity, we show that ATJ is a positive and significant determinant of economic growth. The results hint at a stronger impact of ATJ on economic development in less developed societies. The second chapter analyses if immigration (in terms of both size and composition) can affect the labor market regulation in the destination country. To examine this link, we build a novel workers' protection measure based on 36 labor law variables over a sample of 70 developed and developing countries from 1970 to 2010. Exploiting a dynamic panel setting using both internal and external instruments, we establish a new result: immigration impacts workers' protection in the direction of the origin country workers' protection (composition channel), while we find a small negative or null effect for the immigrant population (size channel). The third and last chapter investigates the impact of temporary border controls on stock market returns. To do so, we first document a unique dataset on the reintroduction of border controls constructed from official documents. Then, we consider two complementary research designs: an event study exploiting the first refugee-induced border control in Germany in September 2015, and a difference-in-difference analysis covering all border controls in the Schengen area between 2006 and 2016. In both analyses, (ECGE - Sciences économiques et de gestion) -- UCL, 2022

This doctoral research was completed over a long period of time (2010-2022) and is positioned between the world of museums and the information and communication sciences. The start of this research (October 2010) corresponds to a period when museums began to register in larger numbers on Facebook and Twitter. At the same time, the information and communication sciences were revisiting the concepts of audiences, communities or participation, in light of the Internet and social network sites. Surveys on museum practices show that access to museums is strongly linked to socio-economic criteria, particularly the education level of visitors. Museums have tried and are still trying to reduce these inequalities of access thanks to various mediation tools, including their Facebook and Twitter accounts. Do these social network sites renew the relationship between museums and audiences, do they make it possible to go beyond this relationship of access, do we find more traces of interaction, or even participation? To answer this question, which is the main theme of this doctoral research, we chose to focus on the uses of Facebook and Twitter by museums that are less studied than the so-called superstar museums such as the Musée du Louvre or the British Museum. The four museums that provide the basis for this research are located in Belgium (Musée royal de Mariemont and Museum aan de Stroom) and in the Grand Duchy of Luxembourg (Musée national d’histoire et d’art and Mudam). First, a content analysis was carried out on data extracted from the Facebook and Twitter accounts of the four museums, which covers one year of uses (2011-2012). This analysis was useful on two levels. The first is methodological. Despite the small amount of data (1998 tweets, 328 posts and 679 Facebook comments), it corresponds with issues related to Big Data, particularly the ethical questions of data extraction and the choices made in delimiting the corpus of the analysis, which can have important conse, Cette recherche doctorale a été menée sur un temps long (2010-2022), elle se situe entre le monde des musées et les sciences de l’information et la communication. Le départ de cette thèse (octobre 2010) correspond à une période où les musées ont commencé à s’inscrire en plus grand nombre sur Facebook et Twitter. Au même moment, les sciences de l’information et de la communication revisitaient les concepts de publics, de communautés ou de participation, au regard d’Internet et des médias sociaux en ligne. Les enquêtes sur les pratiques muséales montrent que l’accès aux musées est fortement lié à des critères socioéconomiques, particulièrement le niveau d’éducation des visiteurs. Les musées ont tenté et tentent encore de diminuer ces inégalités d’accès grâce à différents outils de médiation, parmi lesquels figurent aujourd’hui leurs comptes Facebook et Twitter. Ces dispositifs en ligne renouvellent-ils les relations entre musées et publics, permettent-ils de dépasser cette relation d’accès, retrouve-t-on plus de traces d’interaction, voire de participation ? Pour répondre à cette question qui est le fil rouge de cette thèse, nous avons choisi de nous concentrer sur les usages de Facebook et Twitter par des musées moins étudiés que les musées dits superstars tels que le Musée du Louvre ou le British Museum. Les quatre musées qui constituent le terrain de cette recherche se situent en Belgique (Musée royal de Mariemont et Museum aan de Stroom) et au Grand-Duché de Luxembourg (Musée national d’histoire et d’art et Mudam). Dans un premier temps, une analyse de contenu a été effectuée sur des données extraites des comptes Facebook et Twitter des quatre musées, ce qui correspond à une année d’usages (2011-2012). Cette analyse a été utile à deux niveaux. Le premier se situe à un niveau méthodologique. Malgré le nombre peu important de données (1998 tweets, 328 billets et 679 commentaires Facebook), celles-ci partagent des enjeux liés aux Big Data, particulièrement les questi, (COMU - Information et communication) -- UCL, 2022

The thesis deals with restorative justice in France, which appeared through the inquiry as an extra “touch of soul” to the criminal justice system. It is mainly rooted in the sociology of professions, the sociology of the State, and a political sociology of justice. The thesis analyzes the conditions of the emergence of restorative justice in the country and those of its integration into the penal institution. It unpacks the different types of investments - personal, professional and sociopolitical - that allow it to maintain itself within it. In doing so, it clears an object that has never been studied through this prism in France, and for which empirical inquiries on its practices are also lacking in the international literature. In the thesis, we meet the functioning of a State that tries with restorative justice to remotivate its employees by offering them a new project, a new tool, but above all an extra “touch of soul” to their activity in a context of rationalization and managerialization of judicial activity perceived as burdensome. More broadely, the study of its diferent investments shows how expectations in terms of listening, dialogue and empathy progressively transform the penal institution. These come from all persons subject to the law but also from its own workers and parajudicial partners. The investigation draws mainly on a multi-sited and sustained ethnography of the world of restorative justice in France. This ethnography lasted for more than three years, between 2016 and 2020. It is also based on 71 semi-structured interviews conducted in eighteen different cities. These interviews were held with individuals involved in restorative justice at different levels and from different sectors in France., La thèse porte sur la justice restaurative en France, objet par lequel elle réalise une sociologie politique d’un « supplément d’âme » à la justice pénale. Elle est principalement ancrée dans la sociologie des professions, de l’action publique, et une sociologie politique de la justice. Elle étudie les conditions de l’émergence de la justice restaurative en France, de son intégration dans l’institution pénale, et les différents investissements, personnels, professionnels et sociopolitiques, qui la maintiennent en son sein. Ce faisant, elle défriche un objet encore jamais étudié par ce prisme dans ce pays, et dont les enquêtes sur ses pratiques font également défaut dans la littérature internationale. On y découvre entre autres le fonctionnement d’un Etat qui tente de remotiver ses employés en leur offrant un nouveau projet, un nouvel outil, mais surtout un « supplément d’âme » à leur activité dans un contexte de rationalisation et de managérialisation de l’activité judiciaire perçu comme pesant. Plus largement, en étudiant ses différents investissements, la thèse montre comment l’institution pénale est progressivement transformée par des attendus à son endroit, en termes d’écoute, de dialogue et d’empathie, de la part des justiciables mais également de ses propres travailleurs. L’enquête repose principalement sur une ethnographie multi-située et soutenue du monde de la justice restaurative en France durant plus de trois ans, entre 2016 et 2020. Elle s’appuie également sur 71 entretiens semi-directifs réalisés depuis dix-huit villes différentes, essentiellement avec des individus investis à différentes échelles et depuis différents secteurs dans la justice restaurative en France., (POLS - Sciences politiques et sociales) -- UCL, 2022

This thesis studies the strategic interaction between voters and politicians, and aims to provide a clearer understanding of the forces that govern political participation and competition, in order to explain the dynamics and the consequences of rising political polarization. Focusing on different aspects of polarization, the three chapters of this thesis show that considering polarization can help us explain certain alarming phenomena that undermine the stability of representative democracies. The first chapter addresses the relationship between voters’ polarization on economic issues and the polarization of economic policies. This chapter shows that, together with low electoral participation, extreme polarization can explain the lack of implementation of more redistributive policies in response to rising income inequality. The second chapter addresses the polarization of voters’ views on socio-cultural issues, and studies how this affects party polarization on both the economic and the socio-cultural dimension. This chapter sheds light on the complex interaction between these two dimensions of political competition and allows to explain different patterns of polarization in different countries. The third chapter studies the communication between voters and politicians and shows that the perceived polarization of voters’ preferences exacerbates the conflict between the politicians’ and voters’ interests and undermines informative communication between them., (ECGE - Sciences économiques et de gestion) -- UCL, 2022

Beyond the traditional models of femininity promoted in nationalist and Islamic discourses and endogenous feminist movements, models of femininity are being formed in Algeria by active, urban, and veiled women. This thesis focuses on the appearance of this new category of women in the city of Algiers. The work falls within a sociohistorical context of re-Islamization, postcolonialism, and a modernization process prompted from above. The latter profoundly modified traditional attachments and led to new identities while relying on the reification of supposedly authentic patriarchal values, which are associated mainly with women's status. These femininities are characterized by their access to new social positions in a relative tension with gender assignments, giving rise to new social practices and modes of subjectivity that do not unfold following forms of protest or activism. However, their visible and widespread nature participates in the permanent process of boundaries renegotiation imposed by gendered norms. The extension of accepted behaviour for women will thus create new inclusion and exclusion norms in the gender order. Hence, emancipatory trajectories emerge without renouncing the feminine dispositions valued by the socio-cultural context to which they belong. These trajectories are based on individuation processes, such as the pursuit of professional success, the adoption of mobile lives, and decision-making in the family while investing and renewing a complex relationship between femininity and appearance / sexual convenience, with the aim of preserving social reputation, that is to say, by staging a modest self. Being, making, or becoming this type of woman implies a cost, for it requires significant efforts on the part of women: to succeed in their professional and domestic careers. These expectations are not required of men. Paradoxically, these fragmented feminity models participate in establishing a social representation of idealised women who are mod, (POLS - Sciences politiques et sociales) -- UCL, 2022

Cosmic inflation is arguably the most favoured paradigm of the very early Universe. It postulates an early phase of fast, nearly exponential, and accelerated expansion. Inflationary models are capable of explaining the overall flatness and homogeneity of today's Universe at large spatial scales. Furthermore, their predictions give the observed statistical features of the primordial density fluctuations imprinted in the cosmic microwave background and the Universe's large scale structure. However, despite the wide acceptance in the physics community, these models are not absent from criticism. In scalar field inflation, a necessary condition to begin inflation is the requirement of a Universe dominated by the field's potential, which implies a subdominant contribution from the scalar field dynamics, i.e. gradients and field velocities. This has given rise to large amounts of scientific debate and literature on the naturalness, and possible fine-tuning of the initial conditions for inflation. Another controversial issue concerns the ending of inflation, and the fact that a preheating mechanism is necessary to transfer the energy of the inflaton to the bath of highly energetic particles of the hot big bang plasma. In this thesis, we present full general relativistic simulations to study these two problems, with a particular focus on the Starobinsky and Higgs models of inflation, being those the most favoured by the latest observations. First, we consider the fine-tuning problem of beginning inflation from a highly dynamical and inhomogeneous "preinflation" epoch in the single-field case. In our second study, we approach the multifield paradigm of inhomogeneous preinflation, together and consistently, with the preheating phase after inflation. These investigations further confirm the robustness of these types of models to highly inhomogeneous initial conditions, while putting in evidence the non-negligible effects of gravitational effects during the (p)reheating. At the, (SC - Sciences) -- UCL, 2022

This thesis addresses the importance of uncertainty and expectations in the economy by providing four pieces of analysis.1 The first two chapters explore how agents use financial information in the presence of limited information when forming expectations and how financial markets may capture and transmit economic uncertainty. The third chapter provides a textual-analysis based indicator to measure the real-time impact of uncertainty on economic activity during periods with exceptionally high uncertainty such as the COVID-19 crisis, while the fourth chapter explores the role of uncertainty through expectations as a driving factor during large crisis., (ECGE - Sciences économiques et de gestion) -- UCL, 2022

In recent years, many Mexican students have participated in two large-scale national mobilizations : #YoSoy132 in 2012 and the movement in support of the Ayotzinapa rural teachers’ college in 2014. What happened to these students who committed themselves body and soul, for several months, to build another Mexico? To answer this question this dissertation proposes to study the activists' commitment during latency periods through the prism of the processes of subjectivation they experience. When sociologists are interested in what happens after a mobilization, they mostly study the reasons for demobilization, disengagement or entry into institutional politics. This thesis highlights the ins and outs of a third possibility and analyzes how, far from the spotlight, from institutional politics, and from organizations, students engage, act, think, and contribute to gradually changing the Mexico in which they live. By focusing on the subjectivity of the actors, Margot Achard not only shows that the activists' commitment continues after a large mobilization, but also seeks to understand how they live this commitment. Based on their experiences and encounters, students will shape and implement their own long-term activism during the latency period., Ces dernières années, les étudiants mexicains ont participé en masse à deux mobilisations nationales de grande ampleur : #YoSoy132 en 2012 et le mouvement de soutien à l’école normale rurale d’Ayotzinapa en 2014. Que sont devenus ces étudiants qui se sont engagés corps et âme, durant plusieurs mois, pour un autre Mexique ? Pour répondre à cette question cette thèse propose d’étudier l’engagement des activistes durant les périodes de latence par le prisme des processus de subjectivation qu’ils vivent. Quand les sociologues s’intéressent à ce qu’il se passe après une mobilisation, ils étudient majoritairement les ressorts de la démobilisation, du désengagement ou de l’entrée dans la politique institutionnelle. Cette thèse met en évidence les tenants et les aboutissants d’une troisième possibilité et analyse comment loin des projecteurs, de la politique institutionnelle, et des organisations, les étudiants s’engagent, agissent, (se) pensent, et contribuent à changer petit à petit le Mexique dans lequel ils vivent. En prenant le parti de se focaliser sur la subjectivité des acteurs, Margot Achard ne montre pas seulement que l’engagement des activistes se poursuit après une grande mobilisation, mais cherche également à comprendre comment ils vivent cet engagement. En partant de leurs expériences, de leur vécu et de leurs rencontres, les étudiants vont durant les périodes de latence façonner et mettre en œuvre leur propre activisme de long terme., (POLS - Sciences politiques et sociales) -- UCL, 2022

A recommender system is a computer-based information filtering device that automatically selects media content that may be of interest to the user of a digital service. These technologies provide a personalised access to a catalogue of objects too large to be searched manually. The increasing integration of these systems into the digital ecosystem has raised many concerns about maintaining a common public space for individuals to be exposed to information that diverges from their immediate views and interests. This risk is intensified by the interfaces of these devices which, in order to smooth the user experience, hide the workings of the algorithm and limit the user’s involvement in the recommendation process. While it is possible for an experienced user to understand how the system works, it is becoming increasingly difficult for the majority of users to assess the effect of the algorithm on the ordering of information. An important research challenge is therefore to explore alternative design patterns that allow users to understand the effects of these technologies on their media practices. In this thesis, we evaluated the effect of the controllability of a recommender system on the individual autonomy of its users. To do so, we developed Alveho, an experimental platform supplied daily with press articles from the RTBF. For five weeks, the 23 participants of our study were asked to consult this site daily, which is equipped with its own recommender system as well as tools allowing the participants to adjust the algorithm’s behaviour. By recording our participants’ interactions with the system and conducting individual interviews, we were able to observe their behaviour precisely during the study. Our results indicate that the availability of tools to control the algorithm is not a sufficient condition for the development of user autonomy. This finding can be explained by the significant cognitive overload required by the use of these additional components. We we, Un système de recommandation est un dispositif informatique de filtrage de l’information qui sélectionne de façon automatique des contenus médiatiques susceptibles d’intéresser l’utilisateur d’un service numérique. Ces technologies permettent de fournir une porte d’accès personnalisée à un catalogue d’objets trop volumineux pour être consulté manuellement. L’intégration croissante de ces systèmes au sein de l’écosystème numérique a suscité de nombreuses inquiétudes quant au maintien d’un espace public commun permettant aux individus d’être exposés à des informations qui divergent de leurs opinions et intérêts immédiats. Ce risque est accentué par les interfaces de ces dispositifs qui, afin de lisser l’expérience utilisateur, masquent le fonctionnement de l’algorithme et limitent l’implication de l’utilisateur dans le processus de recommandation. S’il est possible pour un utilisateur expérimenté d’appréhender le fonctionnement du système, il devient de plus en plus difficile pour la majorité des usagers d’évaluer l’effet de l’algorithme sur l’organisation de l’information. Un enjeu de recherche important consiste donc à explorer des trajectoires de design alternatives permettant aux utilisateurs d’appréhender par eux-mêmes les effets de ces technologies sur leurs pratiques médiatiques. Dans le cadre de cette thèse, nous avons évalué l’effet de la contrôlabilité d’un système de recommandation sur l’autonomie individuelle de leurs utilisateurs. Pour ce faire, nous avons développé Alveho, une plateforme expérimentale alimentée quotidiennement en articles de presse issus de la RTBF. Pendant cinq semaines, les 23 participants de notre étude furent amenés à consulter quotidiennement ce site qui est équipé de son propre système de recommandation ainsi que d’outils permettant aux participants d’ajuster le comportement de l’algorithme. L’enregistrement des interactions de nos participants avec le système ainsi que la réalisation d’entretiens individuels nous permirent d’obser, (COMU - Information et communication) -- UCL, 2022