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The conference is co-organized by the University of Namur, Belgium and Wuhan University of Technology, China and supported by Foshan Xianhu Laboratory and other organisms.More info on the GCMC2025 website...

Jury Prof. Benoît MUYLKENS (URVI, Université de Namur), PresidentProf. Carine MICHIELS (URBC, Université de Namur), SecretaryProf. Xavier DE BOLLE (URBC, Université de Namur)Prof. René REZSOHAZY (LIBST, Université catholique de Louvain)Prof. Florian STEINER (Dept. of Molecular and Cellular Biology, Université de Genève)Prof. Germano CECERE (Department of developmental and Stem Cell Biology, Institut Pasteur) Summary In animals, germ cells are often distinguished from somatic lineages at the earliest stages of embryogenesis. In some organisms, germ blastomeres appear to enter a state of transcriptional quiescence. For example, in the worm Caenorhabditis elegans, transcription is activated in somatic blastomeres as early as the 4-cell stage, whereas it is not initiated in germline blastomeres until the 100-cell stage. This transcriptional repression in germ blastomeres has been attributed to the PIE-1 protein, specifically localized in these cells from the first embryonic division. PIE-1 is thought to inhibit the activity of CDK-9, a cyclin-dependent kinase previously considered essential for the phosphorylation of serine 2 (CTD-Ser2) of the C-terminal domain (CTD) of RNA polymerase II and for transcription elongation. However, recent studies, showing that embryogenesis proceeds normally in a mutant strain expressing a CTD in which serines 2 is replaced by an alanine (CTD-S2A) and identifying CDK-12 as the main kinase phosphorylating CTD-Ser2, call this model into question.To study the transcriptome of germline blastomeres in the worm C. elegans, an approach combining cell sorting and RNA sequencing (RNA-seq) was developed. Pilot analyses validated this method on a wild-type strain, enabling its use on a strain in which PIE-1 can be specifically degraded using the Auxin-Inducible Degron (AID) system. This made it possible to examine the effect of PIE-1 depletion on the transcriptome of germline blastomeres revealing that in its absence, germline blastomeres adopt a transcriptional profile close to that of somatic blastomeres, confirming the fundamental role of PIE-1 in preserving germline identity during embryogenesis. In parallel, the fission yeast Schizosaccharomyces pombe was used to analyze the consequences of PIE-1 expression in a heterologous organism. The results showed that PIE-1 by localizing near transcription termination sites induces further transcription by RNA polymerase II beyond the termination site, leading to transcription of intergenic regions. These observations led to the hypothesis that in C. elegans,within germinal blastomeres, PIE-1 might regulate alternative polyadenylation in 3' untranslated regions, producing longer RNA isoforms susceptible to degradation. In the absence of PIE-1, shorter isoforms could be generated, allowing accumulation of somatic transcripts and potentially degradation of maternal mRNAs via somatic protein translation. Although further investigations are required in C. elegans to validate this hypothesis, it provides an innovative conceptual framework for understanding the role of PIE-1, independent of CTD-Ser2 phosphorylation.

Jury Prof. Marielle BOONEN (UNamur), presidentProf. Henri-François RENARD (UNamur), secretaryProf. Claire HIVROZ (PSL University)Prof. Michel GHISLAIN (UCLouvain)Prof. Pierre VAN DER BRUGGEN (UCLouvain)Prof. Ludger JOHANNES (PSL University)Prof. Pierre MORSOMME (UCLouvain) Summary Clathrin-independent endocytosis (CIE) mediates the cellular uptake of endogenous and exogenous cargoes, including bacterial toxins and viruses. Endophilin A3-mediated endocytosis is a specific CIE mechanism that differs from fast endophilin-mediated endocytosis (FEME), with ALCAM and L1CAM being the first confirmed Endophilin A3-specific cargoes. Here, we report ICAM1 as a new Endophilin A3-dependent endocytic cargo. ALCAM and ICAM1 are important components of immune synapses (IS), which are polarized structures formed between immune cells and target cells, such as cancer cells. These molecules transduce essential co-stimulatory signals to T cells to help their effective activation and proliferation. We find that both ALCAM and ICAM1 serve as cargoes for retromer-dependent retrograde transport to the trans-Golgi network (TGN) in cancer cells. Interestingly, disrupting Endophilin A3-mediated endocytosis or retromer-dependent retrograde transport machinery impairs activation of autologous cytotoxic CD8 T cells, possibly by affecting the polarized redistribution of immune synapse components at the plasma membrane. Altogether, our findings demonstrate that CIE and retrograde transport are key pathways in cancer cells that promote the activation of cytotoxic CD8 T cells.

Jury Prof. Yves CAUDANO (UNamur), chairmanProf. André FÜZFA (UNamur), secretaryProf. Dominique LAMBERT (UNamur)Dr. Jérémy REKIER (Observatoire royal de Belgique et UCLouvain)Prof. Dr. Félix FINSTER (Regensburg University) Summary Sounding the Universe with a relativistic solar sailboat or Einstein-Dirac fermionsThe Universe exerts a curiosity on man that is both undeniable and fundamental. To unravel the mysteries of the Cosmos, man is driven to develop two major investigative strategies: direct exploration by sending space probes, and indirect exploration by observing cosmic electromagnetic fields, gravitational waves or particles such as fermions.Following these two strategies, in this thesis we develop, in the first approach (consisting of sending a space probe), a relativistic kinematic and dynamical model of photonic sails (light sails) with arbitrary reflectivity and absorbance, moving in a non-rectilinear manner with the aim of exploring interstellar space. The problem is to determine the sail's trajectory in a Minkowski spacetime, a four-dimensional variety. From detailed calculations, we obtain the sail's universe line in the laser reference frame as a function of the sail's proper time.The second approach applies the Two-State Vector Formalism and weak measurements to a homogeneous, isotropic cosmological framework. By coupling Dirac spinners to classical gravity, we calculate weak values of the energy-impulse tensor, the Z component of spin and pure states. Extending the work of Finster and Hainzl on Einstein-Dirac cosmology, we show that the accelerated expansion of the Universe can be interpreted as a consequence of post-selection. We also demonstrate that weak measurements can amplify signals using simpler equipment, thanks to judicious selection of the initial and final state vectors. In addition, this procedure highlights certain geometric properties of the Cosmos' three-dimensional space, offering a new way of exploring the structure of the Universe.We also examine the mathematical structure on which the Dirac equation rests beyond the usual dimension and signature. This reveals a rich internal symmetry and gives rise to a particularly aesthetic diagrammatic representation. Abstract Probing the Universe with a Relativistic Light Sail or Einstein-Dirac FermionsHumanity's profound curiosity about the cosmos is both undeniable and fundamental. To demystify the Universe, humankind is compelled to develop both direct and indirect probing strategies: direct exploration through physical visits using probes, and indirect exploration by observing cosmic electromagnetic field, gravitational waves and particles such as fermions.Building on these two strategies, this thesis proposes two distinct approaches to probing the Universe. In the first approach, we present a relativistic kinematic and dynamic model of light sails with arbitrary reflectivity and absorptance, undergoing non-rectilinear motion as a method of interstellar exploration. The problem involves solving for the trajectory of the sail in a 4-dimensional Minkowski spacetime manifold. By detailed computation, we derive the worldline of the sail in the laser's frame in the sail's proper time.The second approach applies the Two-State Vector Formalism and weak measurements to a spatially homogeneous and isotropic cosmological framework. Coupling Dirac spinors with classical gravity, we compute weak values of the energy-momentum tensor, the Z-component of spin, and pure states. Extending the work of Finster and Hainzl on Einstein-Dirac cosmology, we demonstrate that the Universe's accelerated expansion can be interpreted as a consequence of post-selection. We also show that weak measurements can amplify signals with simpler equipment by carefully selecting initial and final state vectors. This process also reveals geometric properties of the spacelike three-manifold of the Cosmos, opening new way on probing the structure of the Universe.We explore also the mathematical framework underlying the Dirac equation beyond the standard dimension and signature. This enterprise reveals its symmetrically rich properties and aesthetic diagrammatic representation.

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)

The scientific programme will include 14 academics presenting their work during keynote lectures, a series of oral communications presented by tenured professors, experienced researchers, PhD students or postdoctoral fellows, and two poster sessions. More information and registration

Depuis son inauguration en 2019, l’observatoire astronomique de l’UNamur a déployé un programme pédagogique et de médiation scientifique ouvert à toutes et à tous, avec l’ambition de faire découvrir les sciences par le prisme de l’observation des merveilles du ciel. 5 ans plus tard, le pari est réussi ! La petite équipe qui anime les lieux multiplie les collaborations et les activités proposées aux étudiantes et aux étudiants, aux écoles et au grand public. Cet automne, l’Observatoire astronomique célébrera l’empreinte durable qu’il a construite dans les yeux et les cœurs de son public en fêtant son 5e anniversaire. Une occasion de rassembler la communauté qui s’est développée autour de ses projets passés, présents et futurs ! The program 11am-4pm: Tours of the observatoryUNamur - Faculté des sciences12pm-6pm: Opportunity to visit the Stellar Scape exhibitionLe Pavillon de la Citadelle de Namur6:30pm: Academic session and receptionUNamur - Faculty of Science (S01) Requested registration via ticketweb: https://www.billetweb.fr/5-ans-de-lobservatoire-antoine-thomas

A drink will be organized following the lecture.This lecture is proposed by "Kàp to UNIVERSEH", the kot-free space popularization project of the University of Namur, and Local Student Club of UNIVERSEH.When: Wednesday, February 26, 2025 at 7pmWhere: Faculty of Sciences - Auditorium S01Free I want to register

Practical info Date: Wednesday, March 12, 2025Location: PA01, entrance will be via the Faculty of Science lobby6:45pm: Doors open7:15pm: Show startsPrice and ticket sales: €5 pre-sale / €7 on the daySales: At lunchtime throughout the week of March 3 in the college hall!Payment: We prefer cash, but also accept payment by QR code or bank transfer. Read more

The IPCC warns of the growing impact of global warming on water, with more frequent droughts and floods threatening global supplies. By 2050, 42% of river basins will be severely affected, and flood damage could quadruple in the event of 4°C warming. Although they bear little responsibility, the most vulnerable populations suffer the worst consequences. In Wallonia, recent climatic disasters and water pollution illustrate the stakes. To raise public awareness, an event is being organized in Charleroi with debates and screenings.Program17:00 | Introductory session Head of UNESCO Belgium Mr Aurélien Dumont, Secretariat of UNESCO's Intergovernmental Hydrological Programme, World Water Situation17:40 | Screening of the film "H2O, water, life and us: the Emergency"18:30 | Break18:45 | Lectures and debate Prof. Dr. Marnik Vanclooster (U.K.). Marnik Vanclooster (UCLouvain), "Situation en Wallonnie" Prof. Alfred Bernard (UCLouvain), "Normes et toxicologie" Debate Moderated by Prof. Karim ZouaouiBouin (UCLouvain). Karim ZouaouiBoudjeltia (ULB), with the participation of Aurélien Dumont, Marnik Vanclooster, Alfred Bernard.20:30 | Cocktail dinnerGRATULAR : Registration required: f.amer@wbi.beThe members of the "exact and natural sciences" Sub-CommissionBernard Feltz (UCLouvain, Chairman), Bertrand Hespel (UNamur), Marie-Geneviève Pinsart (ULB, CIGB), René Rezsohazy (UCLouvain), Frédéric Rychter (Secrétaire général), Olivier Sartenaer (UNamur), Didier Serteyn (ULiège), Anne Staquet (UMons), Marnik Vanclooster (UCLouvain), Karim Zouaoui Boudjeltia (ULB)

Dear teachers, We are pleased to invite you to a unique educational experience at the Antoine Thomas Astronomical Observatory. Offer your students the opportunity to discover the Antoine Thomas Astronomical Observatory, an observatory built on the very site where the Jesuit fathers established their own observation, training and research dome in the 19th century. Located in downtown Namur, in the heart of the university, our observatory is equipped with state-of-the-art instruments, for both night-time and daytime observation, with one of Belgium's largest solar telescopes. A visit to the observatory allows you to discover how astronomy is practiced today and - weather conditions permitting - to observe the sun in complete safety. Plan your visit today! To organize a school visit, please complete the registration form available on our website. Practical information:Guided tour 1ère to 6ème secondaire 1:30 pm to 2:30 pm or 3:00 pm to 4:00 pm Faculty of Medicine - Place du Palais de Justice, Namur Gratuit - Sur inscription The observatory is not accessible to people with reduced mobility Next date:February 11, 2025This activity is organized with the support of Wallonie Recherche. Visit registration