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Abstract Estrogens originating from human and animal excretion, as well as from anthropogenic sources such as cosmetics, plastics, pesticides, detergents, and pharmaceuticals, are among the most concerning endocrine-disrupting compounds in aquatic environments due to their potent estrogenic activity. While their effects on fish reproduction are well documented, their impact on development, particularly metamorphosis, remains poorly studied. This hormonal transition, mainly controlled by the thyroid axis, is essential for the shift from the larval to the juvenile stage in teleosts.The effects of two contraceptive estrogens on zebrafish (Danio rerio) metamorphosis were evaluated: 17α-ethinylestradiol (EE2), a synthetic reference estrogen, and estetrol (E4), a natural estrogen recently introduced in a new combined oral contraceptive formulation. Continuous exposure from fertilization to the end of metamorphosis allowed the assessment of morphological changes, disruptions of the thyroid axis, and modifications of additional molecular pathways potentially involved in metamorphic regulation.EE2 induced significant delays and disturbances in metamorphosis, affecting both internal and external morphological traits, confirming its role as an endocrine disruptor of concern. In contrast, E4 did not cause any detectable morphological alterations even at concentrations far exceeding those expected in the environment, indicating a limited ecotoxicological risk. Molecular analyses showed that EE2 strongly affected thyroid signaling and energy metabolism during metamorphosis, whereas E4 induced only minor transcriptional and proteomic changes.This study provides the first evidence that EE2 can disrupt zebrafish metamorphosis and highlights the importance of including this developmental stage in ecotoxicological assessments. The results also suggest a larger environmental safety margin for E4, although further research is needed to clarify the mechanisms linking estrogen exposure to metamorphic regulation.JuryProf. Frederik DE LAENDER (UNamur), PresidentProf. Patrick KESTEMONT (UNamur), SecretaryDr. Sébastien BAEKELANDT (UNamur)Dr. Valérie CORNET (UNamur)Prof. Jean-Baptiste FINI (Muséum National d'Histoire Naturelle, Paris)Dr. Marc MULLER (ULiège)Prof. Veerle DARRAS (KULeuven)

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.

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)

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.

Supported by the SPW Research’s Win4SpinOff program and led by the University of Liège through its Mass Spectrometry Laboratory (MSLab, Faculty of Science) and the University of Namur through its Laboratory of Molecular Cancer Biology, (NARILIS, LBMC, Faculty of Medicine), the VENOM2 project explores the potential of peptides derived from animal venoms to develop new diagnostic and therapeutic solutions in oncology.

The discovery of nuclear energy marked a turning point in human history. Today, alongside debates about its role in energy production and its destructive potential, nuclear energy continues to be used in a wide range of fields, such as medical research and cancer therapies. At UNamur, nuclear energy is thus at the heart of the work of biologists, physicists, and art historians.

At the University of Namur, a thesis led by Fabian Delhalle, with support from SPW Research as part of the Win4Doc program, is exploring an innovative approach to producing proteins of therapeutic interest. In collaboration with Bio-Sourcing and the Walloon Center for Agricultural Research, this project aims to better understand the mechanisms of lactation in goats in order to optimize biopharmaceutical production that is more accessible, more flexible, and more environmentally friendly.

On June 23, 2026, the F.R.S.-FNRS published the list of recipients of various doctoral and postdoctoral fellowships and Télévie projects (cancer-focused research). Among them, numerous researchers from UNamur received funding.

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

The PDID symposium is finally back in 2026! Organized every two years by the Belgian Biophysical Society (BBS) and the Laboratoire de Chimie Physique des Biomolécules (CPB), the PDID symposium is an intimate and friendly event for exchanging new ideas and meeting leading experts in the field in the quintessentially Belgian city of Namur, the capital of Wallonia, located at the confluence of the Meuse and Sambre rivers.We welcome participants from any scientific background who are particularly interested in delving into the world of biomolecular dynamics and exploring their unique behaviors, including structural transitions, interaction networks, protein-ligand interactions, self-assembly, amyloid fibrillation, condensation, phase separation, and phase transitions. Through the lens of biophysics, biochemistry, bioinformatics, and molecular biology, the program aims to cover both experimental and computational approaches for characterizing such intricate and elusive systems in health-related, biotechnological, and biomaterial contexts. Detailed program and registration here