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JuryProf. Johan WOUTERS (UNamur), ChairProf. Steve LANNERS (UNamur), secretaryProf. Stéphane VINCENT (UNamur)Prof. Johan WINNE (UGent)Prof. Andrew MITCHELL (Illinois State University)AbstractTaxpropellane is a taxane complex with a particularly elaborate structure. Although its biological properties are still unknown, its structural complexity makes it a synthetic target of choice. The approach developed in this thesis is based on a retrosynthetic simplification toward a bicyclo[5.4.0]undecane, the preparation of which requires new methodologies, in particular the development of an (5+2) oxydopyrylium cycloaddition using a temporary bridge to construct the required bicyclic compounds.Oxydopyrylium species are highly reactive aromatic intermediates, commonly used to synthesize 7-membered rings via cycloaddition reactions. Their use for intermolecular cycloadditions is severely limited due to their rapid dimerization when the dipolarophile is not sufficiently reactive. The strategy developed in this work relies on the use of a temporary ether-type linker to overcome this limitation. Numerous bicyclic compounds have thus been efficiently synthesized using this methodology. We have shown that this diastereoselectivity depends solely on how the two reactive fragments are linked. Thus, the proposed methodology allows for complete control of stereoselectivity. The cleavage of the linker has also been investigated. This can be achieved in two different ways. This work extends the use of oxidopyrylium ions in synthesis, and this methodology will be applied to the total synthesis of taxpropellane, following the synthesis of a suitable dipolarophile also described here.

JuryProf. Joseph WINKIN (UNamur), ChairProf. Timoteo CARLETTI (UNamur), SecretaryProf. Alexandre MAUROY (UNamur)Prof. Malbor ASLLANI (Florida State University)Dr. Maxime LUCAS (UNamur)Dr. Riccardo MUOLO (RIKEN Institute)AbstractSynchronization is a ubiquitous phenomenon in the world around us. It is a crucial feature that ensures the proper functioning of many complex systems. The various generators in a power grid must produce alternating current at a common frequency, and the brain’s cortical regions synchronize their activities to enable the brain to control the human body. These systems can be modeled as coupled oscillators, as in the famous Kuramoto model, where entities interact in pairs so that they synchronize globally.However, synchronization can also pose a problem. For instance, excessive synchronization of brain dynamics leads to pathological states such as epileptic seizures. It is therefore necessary to develop methods that reduce global synchronization by locally controlling the dynamics of certain oscillators. In particular, a control scheme based on a Hamiltonian framework has been designed to effectively desynchronize the Kuramoto model.Nevertheless, some limitations remain. First, the controlled nodes are selected at random without considering their specific characteristics. Second, this method is designed to control systems with a network structure—that is, with pairwise coupling—whereas many recent studies have demonstrated the importance of higher-order networks, i.e., group interactions, in modeling such systems.In this Ph.D. thesis, we aim to address these gaps through several studies. We explore the optimal method for selecting controlled nodes to maximize control efficiency, investigate the method’s ability to desynchronize systems with higher-order interactions, and develop a new control method tailored to this framework.Our results not only improve these control techniques but also offer novel perspectives on the synchronization of complex systems. They allow us to better understand the influence of each local entity on collective behavior and the role played by interactions of different orders. Among other things, they shed light on the non-monotonic relationship between synchronization capacity and the strength of higher-order interactions.

Program Overview This event will take place over two exciting days, featuring a diverse program designed to offer a dynamic and interactive experience for all participants. The entire symposium will be conducted in English.On Wednesday, December 9, and Thursday, December 10, two days of scientific and technical sessions will be dedicated to the topics of alternative proteins, the microbiome, and functional ingredients.On Wednesday, December 9, there will be a public lecture (in English) presented by Dr. Patrice Cani on the topic “Nourishing Your Gut: Nutrition, Microbiota, and Health.”For experienced researchers and group leaders, we are organizing a third day on December 11 dedicated to international collaboration, including laboratory visits and a workshop focused on establishing structured collaborative projects. Separate registration is requiredOverview of the ThemesThis symposium is structured around the three projects in the FoodWal portfolio, while pushing their boundaries and framing them within a “One Health” approach.The session titled “Building Sustainable Value Chains for Alternative Proteins: from protein sources to the development of healthy food products” will provide an opportunity to present scientific and technological advances in the creation and characterization of alternative protein sources and products, as well as socioeconomic perspectives on the development, maintenance, and growth of sustainable value chains for alternative proteins.The session titled “Research on the Microbiome and Microbiotics: Innovation in Nutrition for Better Health” will present scientific advances in the characterization, understanding, and modulation of the microbiome, as well as cutting-edge technologies aimed at developing innovative microbiotics.Finally, the session titled “Functional Ingredients and Bioactive Compounds: Food Science and Biotechnology for Health” will focus on scientific advances in the identification, characterization, and understanding of the mechanisms of action of functional ingredients, as well as cutting-edge technologies designed to develop and produce innovative functional ingredients. More information on the FoodWal website Je m'inscris

JuryProf. Steve LANNERS (UNamur), ChairProf. Johan WOUTERS (UNamur), SecretaryProf. Pierre FRANCOTTE (ULiège)Dr. Marie HAUFROID (UCB)Prof. Lionel POCHET (UNamur)AbstractCurrently, Mycobacterium tuberculosis remains the second deadliest infectious agent in the world, responsible for 1.6 million deaths in 2021. The burden and cost of current treatment (6 months and 4,000 euros), coupled with the alarming emergence of antibiotic-resistant strains, underscore the absolute urgency of developing new therapeutic molecules. This study focuses on the Mycobacterium tuberculosis phosphoserine phosphatase (MtSerB2), an enzyme essential for serine biosynthesis and vital to the pathogen’s survival. Furthermore, this protein plays a key role in host invasion (through its interactions with the NF-κB factor and the cellular cytoskeleton), making MtSerB2 a prime therapeutic target for the development of new, potent anti-tuberculosis drugs.One of the innovative strategies explored in this thesis is based on destabilizing the protein’s structure (disruption of protein structure). The goal is to design a molecule capable of disrupting the enzyme’s conformation, thereby causing it to lose its catalytic activity. This new class of molecules is expected to exhibit significantly higher selectivity for MtSerB2 compared to its human homolog, human phosphoserine phosphatase (hPSP).To this end, the Mycobacterium avium phosphoserine phosphatase (MaSerB) was initially used as a model system, justified by its 83% sequence identity with MtSerB2 and its propensity to crystallize rapidly. Initially, a virtual screening of drugs already available on the market was conducted to identify potential inhibitors of MaSerB. Enzymatic assays based on malachite green detectionwere then performed to evaluate the inhibitory activity of the various candidates. The results demonstrated increased selectivity of these compounds for dimeric proteins (MtSerB2 and MaSerB) compared to the human enzyme hPSP.Notably, subsequent enzymatic assays conducted directly on MtSerB2 revealed response profiles that differed from those observed with the MaSerB model. To elucidate the molecular basis of these differences, the structure of the protein in its ligand-bound state is currently being investigated. To this end, protein-inhibitor complexes have been crystallized and will be analyzed by X-ray diffraction.

JuryProf. Timoteo CARLETTI (UNamur), ChairProf. Anne-Sophie LIBERT (UNamur), secretaryProf. Benoît FRENAY (UNamur)Prof. Ugo LOCATELLI (University of Rome Tor Vergata)Prof. Konstantin BATYGIN (California Institute of Technology)Prof. Adrien LELEU (University of Geneva)AbstractThe growing number of extrasolar systems detected over the past three decades has made it necessary to develop fast and reliable methods for studying the long-term stability of planetary systems. In this work, we address the complex problem of the stability of compact three-planet systems—in which resonant and chaotic behaviors are intrinsically linked—using chaos indicators and machine learning. In the first part, we design four (variational and non-variational) chaos indicators and test their performance on a synthetic dataset. In the second part, we examine the predictive power of the chaos indicators when combined with different machine learning strategies. Finally, we apply these methods to a synthetic population generated by the Bern formation model, providing results on the long-term behavior and dynamical characterization of the multiple-planet systems in this population. Our analysis highlights the effectiveness of the dynamical tools developed here for assessing the stability of near-resonant systems and paves the way for their use in future space missions.

Organizing CommitteeMaxime Hilbert (University of Namur)Lucie Boël (Jean Moulin University of Lyon 3, IRPhiL)Alexandre Francq (University of Paris 1 Panthéon-Sorbonne, Gustave Roussy Institute, Montpellier Institute of Functional Genomics)Eve-Aline Dubois (University of Namur)Azat Garaev (Catholic University of Louvain)Frida Trotter (Independent Researcher)Doan Vu Duc (University of Namur)Victoria Van Gheem (Catholic University of Louvain)Scientific CommitteeChristine Clavien (University of Geneva, iEH2)Alexandre Guay (Catholic University of Louvain)Quentin Hiernaux (Free University of Brussels)Vincent Ardourel (University of Paris 1 Panthéon-Sorbonne, CNRS)Julie Jebeile (CNRM, CNRS)Baptiste Le Bihan (University of Geneva)Soazig Le Bihan (University of Montana)Matteo Mossio (University of Paris 1 Panthéon-Sorbonne)Olivier Sartenaer (University of Namur)Pieter Thyssen (University of Liège)Laurence Bouquiaux (University of Liège)Antonine Nicoglou (University of Tours) More info

The members of the jury are:Prof. Laura RIZZERIO (Chair), UNamur; Prof. Laurent RAVEZ (Advisor, Secretary), UNamur; Prof. Aude BANDINI, University of Montreal; Prof. Bertrand HESPEL, UNamur; Prof. Sami RICHA, Saint Joseph University of BeirutProf. Grégoire WIEËRS, UNamurThe announcement will be followed by a reception in the Academic Hall.

Practical information:💶 Admission: Free🧑 Target audience: All ages📅 Date: Friday, May 22🕙 Hours: 6:00 PM to 12:00 AM (continuous) (Except for Observatory tours by reservation)📍 Location: Cour de médecine - 3 Rue Joseph Grafé, NamurOn the programLe Confluent des Savoirs, UNamur’s research outreach and public engagement service, invites you to experience an exceptional evening at the heart of the university. Step inside spaces usually off-limits to the public and be amazed by the wealth of activities on offer.Explore the zoology collections and discover the animal world through fascinating specimens and observations. Then take to the skies with tours of the Antoine Thomas Astronomical Observatory—available by reservation only—for a deep dive into the mysteries of the heavens.At the Moretus Plantin University Library (BUMP), let yourself be swept up in a captivating scavenger hunt, following in the footsteps of two iconic figures from Namur folklore: a fun adventure blending puzzles and exploration.Also travel back in time by meeting researchers who reveal the secrets of medieval parchments. Between history and the exact sciences, discover how scientific analysis today makes it possible to identify the animal origin of these precious writing materials.Finally, delve into the heart of today’s environmental challenges with the exhibition “Sentinels in Troubled Waters.” This cross-border research project (ORION) highlights the study and modeling of water quality in the Meuse River basin in the face of human pressures and the challenges of climate change.A unique evening to explore, understand, and marvel… to the rhythm of science.Whether you’re curious, passionate, or simply looking for a unique experience, the Nuit Blanche at UNamur promises a journey rich in discoveries, accessible to all. 

AbstractThe development of efficient heterogeneous acid catalysts is essential for the sustainable valorization of biomass-derived platform molecules. This Ph.D. thesis focuses on the design, synthesis, characterization, and catalytic evaluation of novel acidic materials for two representative biomass upgrading reactions: the ketalization of glycerol to solketal and the conversion of ethyl levulinate to γ-valerolactone. Several classes of catalysts were investigated, including Group IV metal-doped mesoporous silica nanotubes and hollow nanospheres, sulfonic acid-functionalized silica materials, and porous metal phosphonates. The aim was to establish relationships between the properties of the catalysts—in particular their acidity—and their catalytic performance.The results demonstrated that the nature of the metal cation in metal-doped nanostructured silica strongly influences catalyst acidity and reactivity. Furthermore, synthesis parameters such as the loading of the metal cation and the preparation method were shown to control the Lewis/Brønsted ratio and the strength of Lewis acid sites, allowing the tuning of catalytic performance. Materials rich in Lewis acidity preferentially promoted the conversion of ethyl levulinate, while catalysts with higher Brønsted acidity were more effective in glycerol ketalization.The introduction of sulfonic acid groups significantly enhanced Brønsted acidity and led to extremely active catalysts for solketal production. At the same time, studies on layered phosphonates highlighted the crucial role of the phosphoric spacer in ensuring material stability and enabling their reuse over multiple catalytic cycles. For amorphous porous metal phosphonates, key synthetic parameters—including acid concentration, solvent choice, and the use of a templating agent—were found to significantly influence the acidity of the materials and, consequently, their catalytic activity.Overall, this work provides valuable insights into structure-acidity-reactivity relationships and offers guidelines for the rational design of heterogeneous acid catalysts for biomass valorization.JuryProf. Jérémy DEHON (UNamur), ChairProf. Carmela APRILE (UNamur), SecretaryProf. Sophie HERMANS (UCLouvain)Prof. Damien DEBECKER (UCLouvain)Prof. Vera MEYNEN (UAntwerpen)Prof. Tatjana PARAC-VOGT (KULeuven)

Abstract Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous malignancy in which human papillomavirus (HPV) status strongly influences therapeutic response. HPV-positive tumors generally show greater sensitivity to treatment, whereas HPV-negative tumors are associated with a poorer prognosis and increased resistance. This thesis investigated how HPV status shapes cellular adaptation to therapeutic stress, with a particular focus on therapy-induced senescence (TIS), autophagy, and MMS19.HPV- HNSCC cells developed a senescence-like phenotype following cisplatin or X-ray irradiation, whereas HPV+ cells showed limited induction. Silencing of the viral oncogenes E6 and E7 in HPV-positive cells enhanced this phenotype, indicating that HPV actively modulates treatment-induced cellular responses. Proteomic analyses further identified autophagy- and lysosome-related pathways as major features distinguishing HPV- from HPV+ cells. Autophagy inhibition predominantly impaired proliferation and clonogenic survival in HPV- cells, supporting an HPV-dependent autophagy–senescence axis involved in treatment adaptation.The second part of this thesis identified MMS19, a component of the cytosolic iron–sulfur cluster assembly machinery, as a potential determinant of HPV- HNSCC resistance. MMS19 was associated with poorer clinical outcomes, while its silencing impaired proliferation and clonogenic survival, particularly in HPV- cells.Together, these findings identify autophagy-dependent remodeling and MMS19-associated genome maintenance as potential vulnerabilities contributing to therapeutic resistance in HPV- HNSCC. Jury Prof. Anne-Catherine HEUSKIN (UNamur), ChairProf. Carine MICHIELS (UNamur), SecretaryProf. Francis RODIER (UMontreal)Prof. Yves POUMAY (UNamur)Prof. Anabelle DECOTTIGNIES (UCLouvain)Prof. Marc THERRIEN (University of Montreal)Prof. Sue YOM (UCSF)

AbstractIn this work, I aimed to accurately simulate the Raman optical activity (ROA) signatures of flexible solute molecules in their environment. Indeed, these systems are quite challenging due to the potentially huge number of conformers—that is, local minima on the potential energy surface (PES). Furthermore, the environment can drastically alter the PES, as evidenced by experimental ROA spectra that vary significantly depending on the molecule’s conformation and its surroundings. To address this issue, we have developed a hierarchy of methodologies designated M1, M2, and M3. In M1 and M2, the so-called static approach is used: one or more conformers are identified, their geometries are reoptimized at the Density Functional Theory (DFT) level, and their vibrational signatures are simulated, typically using the harmonic approximation. The initial list of conformers was obtained using the CREST algorithm. In M1, the solvent is treated implicitly, whereas in M2, explicit solvent molecules are added around the solute molecule. In M3, we perform ab initio molecular dynamics simulations of the solute molecule surrounded by explicit solvent molecules. The spectrum is obtained by evaluating time-correlation functions along the trajectory. Our first systems of interest were cryptophane derivatives. These are flexible cage-like systems consisting of two hemispheres connected by three -O-(CH₂)n-O- (denoted Cr–nnn) linkers that exhibit chiroptical properties. For Cr–111, the smallest possible cryptophane, the M1 methodology showed good agreement with experimental data, especially in the fingerprint region. However, we demonstrated that the relative ratio between the different conformers was strongly influenced by the choice of the exchange-correlation (XC) functional in our DFT calculations, highlighting the sensitivity of the potential energy surface (PES) description. Cr–222 molecules have been shown to be more flexible, as evidenced by a greater number of significant conformers. The overall agreement with experimental data was also satisfactory. Finally, to test our different approaches (M1–M3), I performed new ROA measurements of amino acids in water at the University of Bordeaux in Dr. Daugey’s laboratory. When compared to our simulations, we clearly observed an improvement in the ROA signatures when explicit water molecules were added to our simulations (M2 vs. M1). Unfortunately, the M3 method did not perform as expected, and further investigation is needed. Overall, I have shown that the PES, as described by our various methodologies, is highly sensitive to various simulation parameters—such as the XC functional, the number and position of explicit solvent molecules, and so on—and that all of these factors strongly influence the simulated ROA signatures.JuryProf. Francesca CECCHET (UNamur), ChairProf. Vincent LIÉGEOIS (UNamur), SecretaryProf. Benoît CHAMPAGNE (UNamur)Prof. Carine CLAVAGUÉRA (University of Paris-Saclay)Dr. Nicolas DAUGEY (University of Bordeaux)

AbstractEnvironmental change rarely occurs as a single, isolated event; organisms and communities typically experience one stressor against the backdrop of another that has already passed. Arunima Sikder’s doctoral thesis examines whether an organism’s past environment shapes its response to the environment that follows, and whether that influence propagates upward to affect the stability of the communities to which these organisms belong.The thesis addresses this question in Synechococcus sp., a globally significant marine primary producer, using thermal and chemical stressors as its two environmental drivers. Working across three levels of biological organization, the study examines how past environments shape responses to subsequent ones—whether they occur in sequence, fluctuate, or occur in combination—using functional traits as the common metric for measuring these responses.The results reveal three key findings. First, sensitivity to a stressor depends on the sequence of exposure, not on the stressor alone. Second, response diversity predicts community stability only when measured under the community’s actual acclimation history, rather than under sustained conditions as conventional wisdom assumes. Third, an apparent contradiction in biodiversity–ecosystem function theory—a negative relationship between functional diversity and performance.Together, these findings suggest that sensitivity, response diversity, and functional diversity should be treated as state-dependent quantities rather than fixed properties, with implications for how the performance of biological systems is measured and modeled under increasingly variable environmental conditions.JuryProf. Alice DENNIS (UNamur), ChairProf. Frederik DE LAENDER (UNamur), SecretaryProf. Maren STRIEBEL (Carl von Ossietzky University Oldenburg)Prof. Giulia GHEDINI (Monash University)Prof. Eli THORÉ (UNamur)