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The biodiversity crisis is not only destroying nature: it also threatens our societies, our well-being, and our survival. Based on scientific assessments and findings from IPBES, this Francqui Chair explores our toxic relationship with nature, the global failure to protect it, and the multiple values of living organisms. We will examine ways to recognize these values, repair our relationship, and bring about the transformative change that is needed.Keen to put the protection of ecosystems back at the center of public debate, UNamur is organizing a second Francqui Chair in Law this academic year with Professor Delphine Misonne on a related theme: "Need for the environment, need for law?"Free event upon registration.  More information and full program I'm signing up

JuryProf. Eli THORÉ (UNamur), PresidentProf. Patrick KESTEMONT (UNamur), SecretaryProf. Ranjàna RANDRIANARIVO (Université d'Antananarivo)Dr. Valérie CORNET (UNamur)Dr. Omayma MISSAWI (UNamur)Prof. Catherine MOUNEYRAC (Université Catholique de l'Ouest)Prof. Gauthier EPPE (ULiège)SummaryThe widespread production and use of plastics have led to their continuous release into the environment. Microplastics (MPs) are now ubiquitous in aquatic ecosystems, where their bioavailability to organisms and potential entry into the food web raise serious environmental and public health concerns. Substantial progress has been made in understanding MP toxicity, and their hazardous potential is now widely acknowledged. However, MP toxicity studies remain complex, as multiple particle characteristics, such as size, shape, polymer type, and sorbed contaminants might influence both bioavailabilityTo bridge this gap, the present thesis adopted a dual, complementary approach: (i) characterizing the environmental occurrence and bioavailability of MPs, and (ii) assessing the ecological relevance of using environmentally derived MPs in in vivo toxicity experiments.Overall, this thesis provides insights into the reproductive and transgenerational effects of environmentally relevant MPs while underscoring the importance of considering particle-pollutant interactions. By combining in situ field data with in vivo laboratory experiments, it demonstrates that the use of environmentally derived MPs represents a more realistic and ecologically meaningful approach to hazard characterization. Further studies should be carried out in this same perspective to generate robust, exploitable data and contribute to establishing a comprehensive MP risk characterization.

JuryProf. Nicolas DENDONCKER (UNamur), PresidentProf. Sabine HENRY (UNamur), SecretaryDr. Sébastien DUJARDIN (UNamur)Prof. Pierre OZER (ULiège)Prof. Emmanuel TWARABAMENYE (University of Rwanda)Prof. Caroline MICHELLIER (MRAC and UCLouvain)AbstractThis research investigates community vulnerability to landslides and floods in Northwestern Rwanda, hazards that frequently interact to produce compound disasters. The research focused on understanding the institutional, social, and structural factors that shape vulnerability and adaptive capacity in this disaster-prone region. Using a mixed-methods approach at local-scale, including institutional analysis, household surveys (n = 904), and field observations, the research highlights how vulnerability is shaped by socio-economic conditions, weak institutional coordination, and limited adaptive capacity. A Contextualized Vulnerability Index (CoVI) was developed to map vulnerability patterns, revealing particularly high vulnerability in landslide-prone and dual-hazard zones. The analysis of adaptive capacity showed that while awareness of hazards is high due to lived experiences, financial constraints, and limited technical knowledge hinder communities' ability to adapt effectively. The study contributes to the literature on social vulnerability and disaster risk reduction by emphasizing the importance of locally grounded, evidence-based strategies to strengthen community resilience in hazard-prone regions.

JuryProf. Régis HALLEZ (UNamur), PresidentProf. Jean-Yves MATROULE (UNamur), SecretaryDr. Rob VAN HOUDT (SCK CEN)Dr. Kristel MIJNENDONCKX (SCK CEN)Prof. Liselot DEWACHTER (UCLouvain)AbstractThe viable-but-nonculturable (VBNC) state is a type of bacterial dormancy triggered by sublethal stress, where cells remain intact but lose the ability to grow on standard media. This poses challenges for microbial monitoring and public health, as VBNC cells can evade detection and might regain virulence upon resuscitation. Copper compounds are explored as antimicrobial agents, however sublethal Cu concentrations were shown to induce the VBNC state in certain bacteria. This thesis investigates the Cu-induced VBNC state in Cupriavidus metallidurans, a metal-resistant betaproteobacterium, and examines the involvement of its Cu resistance determinants (CRDs). While resuscitation is usually mediated by external factors, we aimed to uncover intrinsic processes that enable spontaneous resuscitation, a rare phenotype lacking mechanistic understanding. Proteomic analysis revealed that expression of CRDs, among others, correlated with mitigated dormancy. Time-resolved profiling showed that VBNC cells exhibit highly dynamic proteomes: VBNC entry involved oxidative stress response, and resuscitation correlated with metabolic reconstitution and the strong induction of periplasmic CRDs. Temporal clustering corroborated the explored proteomic modifications. Through mutational studies we identified the plasmid-encoded copAB system as the minimal resuscitation factor, where integrity of the CopA methionine-rich domain proved critical. ICP-MS analysis indicated that detoxification relies on Cu sequestration rather than export. Altogether, this work uncovers key intrinsic factors and proposes a mechanistic basis for spontaneous resuscitation from the Cu-induced VBNC state in C. metallidurans. These insights refine our understanding of the VBNC state as a dynamic survival strategy and of bacterial Cu resistance.

JuryDr Luca FUSARO (UNamur), PresidentProf. Carmela APRILE (UNamur), SecretaryProf. Francesco GIACALONE (University of Palermo)Prof. Paolo PESCARMONA (University of Groningen)Prof. Michelangelo GRUTTADAURIA (University of Palermo)AbstractThis PhD research focused on the design, synthesis, and catalytic evaluation of novel materials based on metal phthalocyanines (MPCs) and imidazolium bromide salts. The initial materials were extensively characterized using a wide range of analytical, spectroscopic, and spectrometric techniques, including solid-state NMR, XPS, TEM, EDX, FT-IR, Raman, CHN analysis, ICP-OES, N₂ physisorption, and TGA. These systems showed remarkable performance in promoting the cycloaddition of CO₂ to epoxides to form cyclic carbonates. Building on these results, a new class of catalysts was developed by covalently anchoring metal phthalocyanines and imidazolium salts onto multi-walled carbon nanotubes (MWCNTs), yielding materials denoted as MPC@MWCNTs. This strategy enabled the creation of a versatile family of catalysts-prepared with different metal centers (Al, Mg, Fe, Ni, Co, Cu, Zn)-while maintaining a unified synthetic approach. The incorporation of MWCNTs was aimed at enhancing both catalytic activity and stability through synergistic support effects. The resulting MPC@MWCNTs were successfully applied in diverse catalytic contexts: CO₂ valorization into cyclic carbonates (Mg-, Fe-, Cu-, and Zn-based systems), nitro-reduction reactions to afford amines (Fe-based system), and electrocatalytic methanol oxidation for energy-related applications (Ni-based system). Overall, this work demonstrated the potential of MPC@MWCNT hybrid materials as robust, tunable, and multifunctional catalysts for sustainable chemical transformations. Attend the event remotely (Teams)

High-Sensitivity Birefringence Mapping Using Near-Circularly Polarized Light I will describe several techniques for mapping a two-dimensional birefringence distribution, which can be classified according to the optical schemes and principles of work:Illumination geometry (transmitted light/reflected light)Image acquisition (sequential acquisition/simultaneous acquisition)Polarization control (electrically controlled variable retardance/mechanical rotation).This classification facilitates a comparative analysis of the capabilities and limitations in these methods for birefringence characterization. Polychromatic polarizing microscopy (PPM) provides unique capabilities to alternative methods. It leverages vector interference to generate vivid, full-spectrum colors at extremely low retardances, down to < 10 nm. PPM is a significant departure from conventional polarizing microscopes that rely on Newton interference, which requires retardances above 400 nm for color formation. Furthermore, PPM's color output directly reflects the orientation of the birefringent material, a feature absent in conventional microscopy where color is solely determined by retardance.Joint seminar of ILEE & NISM!The seminar is open to external people too, no need to register. More info

Abstract Radiotherapy is a cornerstone of cancer treatment and is currently administered to approximately half of all cancer patients. However, the cytotoxic effects of ionizing radiation on normal tissues represent a major limitation, as they restrict the dose that can be safely delivered to patients and, consequently, reduce the likelihood of effective tumor control. In this context, delivering radiation at ultra-high dose rates (UHDR, > 40 Gy/s) is gaining increasing attention due to its potential to spare healthy tissues surrounding the tumor and to prevent radiation-induced side effects, as compared to conventional dose rates (CONV, on the order of Gy/min).The mechanism underlying this protective effect-termed the FLASH effect-remains elusive, driving intensive research to elucidate the biological processes triggered by this type of irradiation.In vitro models offer a valuable tool to support this research, allowing for the efficient screening of various beam parameters and biological responses in a time- and cost-effective manner. In this study, multicellular tumor spheroids and normal cells were exposed to proton irradiation at UHDR to evaluate its efficacy in controlling tumor growth and its cytotoxic impact on healthy tissues, respectively.We report that UHDR and CONV irradiation induced a comparable growth delay in 3D tumor spheroids, suggesting similar efficacy in tumor control. In normal cells, both dose rates induced similar levels of senescence; however, UHDR irradiation led to lower apoptosis induction at clinically relevant doses and early time points post-irradiation.Taken together, these findings further highlight the potential of UHDR irradiation to modulate the response of normal tissues while maintaining comparable tumor control.JuryProf. Thomas BALLIGAND (UNamur), PresidentProf. Stéphane LUCAS (UNamur), SecretaryProf. Carine MICHIELS (UNamur)Dr Sébastien PENNINCKX (Hôpital Universitaire de Bruxelles)Prof. Cristian FERNANDEZ (University of Bern)Dr Rudi LABARBE (IBA)

Welcome to the 1ʳᵉ MG-ERC conference This conference, linked to the research themes of the Chemistry Department, aims to bring together around 100 researchers working in the fields of heteroatom chemistry, coordination chemistry, catalysis, and inorganic chemistry. It represents a real novelty in Belgium in terms of the areas covered, and will enable participants to discover new concepts, ideas and trends in these recent areas of research in chemistry. Here is the list of speakers, who are world experts in their fieldsDr. Daniël Broere (Utrecht University, Netherlands)Prof. Agnieszka Nowak-Król (Universität Würzburg, Germany)Dr. Antoine Simonneau (Université Paul-Sabatier, Toulouse, France)Prof. Dr. Sebastian Riedel (Freie Universität, Berlin, Germany)Dr. Arnaud Voituriez (Université Paris-Saclay, France)Prof. Dr. Alessandro Bismuto (Universität Bonn, Germany)Dr. Christian Hering-Junghans (Leibniz-Institut für Katalyse, Germany)Prof. Connie Lu (Universität Bonn, Germany)Prof. Simon Aldridge (University of Oxford, UK)Dr. Ghenwa Bouhadir (Université Paul-Sabatier, Toulouse, France)Prof. Dr. Viktoria Däschlein (Universität Bonn, Germany)Prof. Viktoria Däschlein-Gessner (Ruhr-University of Bochum, Germany)Dr. Jennifer A. Garden (University of Edinburgh, UK)Prof. Muriel Hissler (Université de Rennes, France)Prof. Jean-François Paquin (Université de Laval, Canada) More information and registration

Something for everyone 09:30 | Welcome ceremony for new students11:00 | Back-to-school celebration at Saint-Aubain Cathedral (Place Saint-Aubain - 5000 Namur), followed by student welcome by the Cercles. Read more

JuryProf. Max COLLINET (UNamur), ChairProf. Johan YANS (UNamur), secretaryProf. Flavien CHOULET (Marie and Louis Pasteur University)Dr. Alexandre FELTEN (UNamur)Prof. Mohammed BOUABDELLAH (Mohammed IV Polytechnic University)Prof. Nadine MATTIELLI (Free University of Brussels)Dr. Augustin DEKONINCK (UMons)AbstractSupergene processes are responsible for the redistribution of metals near the surface and can form economically significant mineral deposits. This PhD thesis investigates the evolution (genesis and timing) of supergene mineralization in polymetallic systems from Morocco (Anti-Atlas and Atlas) and France (Provence). The study combines field observations, petrography, geochemistry, stable isotope analyses, and experimental oxidation to provide a multiscale understanding ranging from microscopic characterization to regional geological evolution.Stable Cu and Fe isotopes show unique fractionation in each deposit, which primarily depends on the primary ore’s isotopic composition. In addition, specific minerals (e.g., arsenates) may strongly influence the Cu fractionation of later-formed minerals (e.g., malachite), which can result in highly variable Cu isotope compositions across deposits. Therefore, Cu and Fe isotopes must be considered site-specific. Experimental investigations complement geological data by quantifying the oxidation rates of pyrite and galena under various conditions. These results highlight that the timing of weathering is reproducible and consistent with natural examples studied in this thesis via (U–Th)/He and K–Ar geochronology. However, pyrite oxidation (4.3 µm/year) is faster than that of galena, which may have a catalytic effect on other sulfides in polymetallic deposits.Overall, supergene mineralization reflects combined controls from mineralogy, host rocks, fluids, climate, and tectonics. This work refines genetic models and provides new tools to describe and constrain secondary mineralization, as well as their potential impact on metallurgical processes.

If the phenomena you observe fascinate you and feed your curiosity, your need to understand and go further, your future starts here. Embark on a captivating journey to the heart of exploration, knowledge and innovation, where every experience shapes your potential. Welcome to the Faculty of Science at the University of Namur!

Physics: An Adventure of the Mind. From the infinitely small to the infinitely large, from elementary particles to galaxies, are you eager to understand the why and how of the natural phenomena you observe?  Why is the sky blue? How does an airplane take off? How does radiation therapy work? What are the effects of global warming? How can nanotechnology revolutionize telecommunications? How can we produce energy without depleting the planet?Physics answers all your questions.