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SummaryAt a time when a stream of research was striving to reformulate quantum mechanics by abolishing operators and substituting functions, Wigner and Szilard proposed in 1932 a quasi-probability distribution defined on phase space thanks to wave functions. They did not explain its genesis.The first part of our thesis proposes a genesis of this quasi-distribution, based on the natural conditions it must fulfill. It briefly examines a pathology it suffers from: exhibiting negative values in certain subdomains of the phase space (hence the "quasi"), a pathology that does no harm to the calculation of mean values. She then shows how, if we take spin into account, with wave functions giving way to spinners, we are led, thanks to the calculation of mean values of observables, to a generalization of this quasi-distribution in the form of a Hermitian matrix. This approach is extended to the Wigner cross transform, i.e. to weak values.An important theorem, which has been the subject of a publication, is proved in the second part of our thesis. Using harmonic analysis, this result expresses weak values in terms of an integral over a Lie group acting on the Hilbert space under consideration. We give two particular examples: SU(2) and SO(3). The case of a quotient group is briefly discussed.In a third section, we recall the well-known link between Clifford algebras and two important equations of quantum physics: the Klein-Gordon and Dirac equations, and its generalization to Riemannian spacetimes.Finally, in a fourth section we introduce spin groups, and use the spin group Spin(3,2) in the context of the Wigner cross transform discussed in the first section.JuryProf. André FÜZFA (UNamur), PresidentProf. Yves CAUDANO (UNamur), SecretaryDr. Thomas DURT (Institut Fresnel and Ecole Centrale Marseille, Marseille, France)Prof. Romain MURENZI (Worcester Polytecnic Institute)Prof. Dominique LAMBERT (UNamur)Prof. Bertrand HESPEL (UNamur)Prof. André HARDY (UNamur)

A team of American researchers, with the help of Frédérik De Laender, professor in the Department of Biology at UNamur, has just published in the prestigious journal Nature. Their study describes how changing stream temperatures and human introductions of fish can alter river biodiversity in the USA.

Two researchers from the University of Namur's Department of Physics, Professor Michaël Lobet and his PhD student Adrien Debacq, are taking a close look at a subject that fascinates the scientific community : superradiance in media with a refractive index close to zero. In an article published this summer in Nature's prestigious journal Light: science & applications, in collaboration with Harvard University (USA), Michigan Technological University (MTU) and Sparrow Quantum, they contribute to the development of quantum computing.

Essay topic Essays on the Empirical Analysis of Crypto-Assets: Market Efficiency, Peg Failures, and Financial Flights Composition of the Jury Promoter: Prof. Jean-Yves Gnabo (UNamur)Other jury members: Prof. Sophie Béreau (UNamur)Prof. Kris Boudt (UGent)Prof. Sarah Bouraga (EM Normandie)Prof. Jérôme Lahaye (Fordham University)Jury president: Prof. Corentin Burnay (UNamur)

Rubber boots, overalls, the bleating of ewes, the smell of straw... The scene is set. On the farm of the Centre de Recherche Ovine, located in the Namur countryside, veterinary students live, for the space of a few days, to the rhythm of lamb births. An intense, formative experience, filled with technical gestures and emotions, supervised by veterinarians from the University of Namur.

Abstract Primarily described as an alarmone, secondary messenger (p)ppGpp, when accumulated, binds to many targets involved in DNA replication, translation, and transcription. In the asymmetrically-dividing a-proteobacterium Caulobacter crescentus, (p)ppGpp has been shown to strongly impact cell cycle progression and differentiation, promoting the non-replicating G1/swarmer phase. Mutations in the major subunits of transcriptional complex, b or b' subunits, were able to display the (p)ppGpp-related phenotypes even in the absence of the alarmone. We identified that the transcriptional holo-enzyme, RNA polymerase (RNAP) is a primary target of (p)ppGpp in C. crescentus. Furthermore, mutations that inactivate (p)ppGpp binding to RNAP annihilated the (p)ppGpp-related phenotypes and phenocopied a (p)ppGpp0 strain. Our RNAseq analysis further elucidated the changes in the transcriptional landscape of C. crescentus cells displaying different (p)ppGpp levels and expressing RNAP mutants. Since the DNA replication initiation protein DnaA is required to exit the G1 phase, we observed that it was significantly less abundant in cells accumulating (p)ppGpp. We further explored its proteolysis under the influence of (p)ppGpp. Our work suggests that (p)ppGpp regulates cell cycle and differentiation in C. crescentus by reprogramming transcription and triggering proteolytic degradation of key cell cycle regulators by yet unknown mechanisms. In Part II, we identified two σ factors belonging to the ECF family that might be involved in this (p)ppGpp-accompanied phenotypes. In Part III, we propose an overlapping role of the ω subunit, RpoZ, and the heat shock subunit, RpoH, in carbon metabolism.JuryProf. Gipsi LIMA MENDEZ (UNamur), PresidentProf Régis HALLEZ (UNamur), SecretaryDr Emanuele BIONDI (CNRS-Université Paris-Saclay)Prof. Justine COLLIER (University of Lausanne)Dr Marie DELABY (Université de Montréal)

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)

The team of professor Xavier De Bolle has just published an article in the prestigious EMBO Journal published by Springer Nature.  His discovery? A lipid transport channel through the cell membrane of Brucella, the bacteria responsible for Brucellosis in cattle. This finding could be used to generate attenuated strains of the bacteria; a process used in vaccine manufacturing. 

Japan is almost 10,000 kilometers from Belgium, a country that fascinates, not least for its rich culture full of contrasts. Researchers at UNamur maintain close ties with several Japanese institutions, particularly in the fields of computer science, mathematics and video games. Let's take a look at some of these collaborations..

A collaboration between UNamur - Hénallux - IFEC Image Image Image Since September 2022, Hénallux and UNamur have been collaborating with IFEC (Institut de Formation de l'Enseignement Catholique) with the aim of raising awareness and training those involved in secondary education in educational differentiation, advocated in the Pacte pour un enseignement d'excellence. To achieve this, various modalities have been devised and implemented: in-school pedagogical days, follow-ups in schools that request them, courses for differentiation referent teachers, courses for CSAs (support and accompaniment advisors).The convention is coordinated by Sandrine Biémar (UNamur) and Alain Bultot (Hénallux), and the team of researchers includes Anne Libert (UNamur), Virginie Meyer (UNamur) and Sylvie Van der Linden (Hénallux). Background This collaborative research is part of a wider project devoted to differentiation, which brings together several courses with different aims and audiences. These include in-school pedagogical training, the training of teacher-referents whose vocation is to be facilitators of the development of differentiation practices in their schools, training for all IFEC CSAs, as well as regular meetings with IFEC in-house trainers interested in this theme. Collaborative research is part of this continuity, with each path nourishing the others. It aims to anchor reflection on differentiation in classroom practices in a mutual enrichment of theory and practice. In practice School courses : pedagogical training and follow-up courses lasting from 1 to several days. CSA course : 4-day training for all CSAs and IFEC. Referent courses : Training of pairs of school referents for 4 days + 1 day. Trainers' courses : community of practice with IFEC internal differentiation trainers Collaborative research path : accompanying teachers over a school year in implementing differentiation practices. The objectives Fostering teachers' power to act by mobilizing and interpreting objective data gathered in the field.Collaborative research is built on negotiation between participants and researchers. Each stage of the research is therefore constructed together, in order to respond as closely as possible to the concerns and issues related to differentiation that are encountered in the specific contexts of each participant.For example, the research question and sub-questions are co-formulated to respond as closely as possible to the concerns and issues in the field regarding the impact of a differentiated teaching posture on student motivation and autonomy.. Methodology This research is inspired by the protocol developed by Schildkamp (2018, 2019) within "Data TEAMS". It aims to develop and foster teachers' power to act through decision-making based on data collection and evaluation of school practices.The data resulting from this research pathway will feed the referent and trainer pathways. In addition, data and productions resulting from this collaborative research will also be destined for colleagues and organizations from the various stakeholders (schools, CSA). Want to get involved? We are looking for pairs of teachers from the same school, which will facilitate the implementation of the process within each school concerned. The themeDevelop and regulate differentiation practices in light of classroom data.The objectivesUnderstand and actUnderstand, through analysis of available classroom data and exchanges of practice between professionals, the effects of a differentiated teacher posture on student motivation and autonomy.Objectivate one's intuition to act effectively.Terms and conditions7 meetings over the course of the year at the Salle des Pros (Rue Godefroid, 7 - in the center of Namur)Why participate?To enrich research by drawing on practices in the field.To enrich your practices thanks to the support of the researcher-trainers.To meet other teachers who share your concerns. Contact For further information, please contact the research teamAnne Libert : anne.libert@unamur.beVirginie Meyer : virginie.meyer@unamur.beSylvie Van der Linden : sylvie.vanderlinden@henallux.be Project coordinator Sandrine Biémar: sandrine.biemar@unamur.be

An international team of researchers has just published an article in the prestigious journal Light: Science & Applications (LSA) from the Nature group.  The teams led by Professors Michaël Lobet and Alexandre Mayer (University of Namur) collaborated with the team led by Professor Shanhui Fan, one of the leading experts in the field, from the prestigious Stanford University in California (USA).  The result: an article entitled ‘Twist-Induced Beam Steering and Blazing Effects in Photonic Crystal Devices’, or the study of beam deflection by twisting in photonic crystal devices.  Come on, let's twist light again at UNamur! 

Abstract This work demonstrates that polymer-coated gold nanoparticles can function not only as radiosensitizers but also as agents for macrophage reprogramming. Specifically, we show that these nanoparticles can repolarize tumor-associated macrophages from the immunosuppressive M2 phenotype to the pro-inflammatory M1 phenotype-a process further enhanced by clinically relevant doses of X-ray radiation. Among the four nanoparticle formulations tested, 50 nm PVP-coated gold nanoparticles were particularly effective in promoting macrophage repolarization and reducing pancreatic cancer cell viability in co-culture, both with and without radiation. These findings highlight a promising strategy to enhance the efficacy of cancer radiotherapy. Jury Prof. Julien COLAUX (UNamur), ChairmanProf. Anne-Catherine HEUSKIN (UNamur), SecretaryProf. Carine MICHIELS (UNamur)Prof. Henri-François RENARD (UNamur)Prof. Michel MOUTSCHEN (ULiège)Dr Dimitri STANICKI (UMons)Prof. Devika CHITHRANI (University of Victoria)