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Summary: Impact of the UPR pathway on the establishment of the UVB-induced senescent phenotype Skin aging, influenced by a combination of intrinsic and extrinsic factors, leads to damage capable of altering skin functions. Among extrinsic factors, ultraviolet (UV) radiation is responsible for skin photoaging. In particular, these elements lead to an accumulation of senescent cells capable of contributing to the development of age-related pathologies such as skin cancers. Indeed, senescence is accompanied by profound morphological and molecular changes within the cell. This includes a modification of its secretome, which becomes enriched with pro-inflammatory cytokines, growth factors and extracellular matrix remodeling enzymes, altering the characteristics of tissues as they age. Nevertheless, the precise mechanisms leading to the senescent phenotype induced by UVB remain largely unknown. In this context, the main objective of this work was to identify molecular mechanisms underlying the establishment of UVB-induced senescence in normal human dermal fibroblasts (NHDFs), mechanisms that could contribute to skin aging. In vitro, we confirmed that repeated UVB exposures induce premature senescence in NHDFs and that this state is associated with activation of the three branches of the UPR (Unfolded Protein Response) pathway responsible for maintaining homeostasis of the endoplasmic reticulum (ER), the primary secretory compartment. These observations were supported by transcriptomic analysis, revealing regulatory elements linked to major senescence pathways and ER functions in UVB-exposed NHDFs. Subsequently, we showed that the ATF6α branch plays a central role in the occurrence of biomarkers of the UVB-induced senescent phenotype. Indeed, ATF6α invalidation not only protects against UVB-induced morphological changes, but reduces the percentage of SA-βgalactosidase (SA-βgal)-positive cells, prevents persistent DNA damage, and alters the expression of major factors of the senescence-associated secretory phenotype (SASP). As SASP exerts, among other things, a pro-tumoral action, we sought to assess whether the conditioned medium (CM) of UVB-exposed fibroblasts invalidated for ATF6α could impact the migration and invasion potential of melanoma-derived cells. However, we did not observe any ATF6α-dependent pro-migratory or pro-invasive effects.To highlight a potential role for ATF6α in another biological process, we exploited our transcriptomic and secretomic analyses and identified a possible effect of ATF6α on the paracrine control of the skin environment. To explore this, we focused on SASP factors (cytokines and metalloproteases) regulated by ATF6α and whose impact on the tissue environment was known. Next, we treated a reconstructed human epidermis (RHE) model with MC derived from NHDFs exposed to UVB or not, and invalidated or not for ATF6α. Surprisingly, we observed that MC from UVB-exposed NHDFs increased RHE thickness and basal keratinocyte proliferation, via an ATF6α-dependent mechanism. Finally, we identified IL8 as a major paracrine factor involved in this process, since IL-8 blockade by neutralizing antibodies prevents excessive keratinocyte proliferation. In conclusion, we report the role of ATF6α in UVB-induced senescence as well as its impact on the preservation of skin homeostasis under stress conditions notably through the regulation of the expression of SASP components. This suggests that ATF6α and its effectors could be promising targets controlling the effects of skin aging.Abstract: Impact of the UPR pathway on the establishment of the senescent phenotype induced by UVBSkin aging, influenced by a combination of intrinsic and extrinsic factors, can result in damage that has the potential to alter skin functions. Among extrinsic factors, ultraviolet (UV) radiation is responsible for skin photoaging. These factors notably contribute to the accumulation of senescent cells which in turn can contribute to the development of age-related pathologies, including skin cancers. Indeed, senescence is characterized by profound morphological and molecular changes within the cell. This includes a modification of its secretome, which becomes enriched in pro-inflammatory cytokines, growth factors, and matrix-remodeling enzymes, altering tissue characteristics during aging. However, the exact mechanisms driving the senescent phenotype induced by UVB remain largely unknown. In this context, the main objective of this work was to identify the underlying molecular mechanisms responsible for the establishment of UVB-induced senescence in normal human dermal fibroblasts (NHDFs), mechanisms that may play a role in skin aging. In vitro, we confirmed that repeated exposures to UVB induce premature senescence of NHDFs and that this state is associated with the activation of the three branches of the Unfolded Protein Response (UPR), which are responsible for maintaining endoplasmic reticulum (ER) homeostasis, the primary cellular secretion compartment. These observations were supported by transcriptomic analysis, revealing regulatory elements related to major senescence pathways and ER functions in UVB-exposed NHDFs. Subsequently, we demonstrated that the ATF6α branch plays a central role in the development of the UVB-induced senescent phenotype. Indeed, the silencing of ATF6α not only protects against morphological changes induced by UVB, but also reduces the percentage of senescence-associated β-galactosidase (SA-βgal) positive cells, prevents the persistence of DNA damage, and alters the expression of major factors associated with the senescence-associated secretory phenotype (SASP).The SASP, exerting a pro-tumoral action, led us to assess whether the conditioned medium (CM) from UVB-exposed fibroblasts invalidated for ATF6α could impact the migration and invasion potential of melanoma cells. However, we did not observe any ATF6α-dependent pro-migratory or pro-invasive effects. To highlight a potential role of ATF6α in another biological process, we further analyzed our transcriptomic and secretomic analyses and identified a possible effect of ATF6α on the paracrine control of the skin environment. To explore this, we focused on SASP factors (cytokines and metalloproteinases) regulated by ATF6α and whose impact on tissue environment was known. Subsequently, we treated a reconstructed human epidermis (RHE) model with CM from NHDFs exposed or not to UVB and invalidated or not for ATF6α. Surprisingly, we observed that the CM from UVB-exposed NHDFs increased the thickness of the RHE as well as the proliferation of basal keratinocytes, via an ATF6α-dependent mechanism. Finally, we identified IL8 as a major paracrine factor involved in this process, as blocking IL-8 with neutralizing antibodies prevented excessive proliferation of keratinocytes. In conclusion, we report the role of ATF6α in UVB-induced senescence and its impact on the preservation of skin homeostasis under stress conditions, particularly through the regulation of the expression of SASP components. This suggests that ATF6α and its effectors could be promising targets for controlling the effects of skin aging. Jury Prof. Yves POUMAY (Department of Medicine, UNamur), chairmanProf. Florence CHAINIAUX (Department of Biology, UNamur), promoter and secretaryProf. Olivier PLUQUET (Canther, University of Lille), co-promoterProf. Isabelle PETROPULOS (Adaptation Biologique et Vieillissement, Sorbonne Université)Prof. Jérôme LAMARTINE (Laboratoire de Biologie Tissulaire et d'Ingénierie thérapeutique, Université Claude Bernard Lyon 1)Prof. Fabienne FOUFELLE (Maladies métaboliques, diabète et comorbidités, Sorbonne Université)

The workshop provides a forum for the discussion of new research directions and applications in Artificial Life, Evolutionary Computation and in related fields, where different disciplines and research areas could effectively meet. It was first held in 2007 in Sampieri (Ragusa), as the incorporation of two separate workshops (WIVA and GSICE).

Initiated in 1969 by Pullmann and Del Re, the congress is an annual meeting to promote collaboration and friendship between Latin-speaking theoretical chemists. In its early years, European researchers were the main contributors. Subsequently, the Latin American community has made a major contribution, with the emergence of teams whose international reputation now extends far beyond our own community.We are delighted to be holding this meeting at the University of Namur, 55 years after the first CHITEL was organised in Paris, France. We are sure that this 2024 edition will once again be an opportunity to take advantage of the good humour and dynamism of Latin to encourage, develop and strengthen scientific exchanges.We look forward to welcoming you at the University of Namur,The CHITEL 2024 Local Organising Committee. Website

EMBO Courses and Workshops are selected for their excellent scientific quality and timelines, provision of good networking activities for all participants and speaker gender diversity (at least 40% of speakers must be from the underrepresented gender). Organisers are encouraged to implement measures to make the meeting environmentally more sustainable.Upon registration - More info and registration on the EMBO website.

On Thursday May 30, for our last Chill&Sciences of the season, Candy Sonvaux and Alexis Coyette, mathematics researchers, invite you to discover the mathematics where the movements of the planets and the spread of viruses intertwine until they impact our society.Chill&Science: enriching encountersWith nearly 20 years' experience of scientific cafés, the Confluent des Savoirs has set up a new concept of scientific encounters. The Chill&Sciences are a unique opportunity for the public to come and discuss and ask questions of experts on research topics related to current affairs and citizen issues.Come and enjoy the unique, relaxed atmosphere of Quai22. Researchers and experts from the seven faculties of the University of Namur will present their research and discuss with you over a drink (or two, but never without exaggeration).In practiceThe meetings are open to everyone aged 16 and over. Evenings are limited to around 20 people to ensure a relaxed atmosphere and to facilitate discussions. Meetings take place if a minimum of 10 people are registered. Except in exceptional circumstances, meetings take place every 2 months at the University of Namur's cultural space, Quai22, located at n°22 Rue du Séminaire.Tarif Participation in a Chill&Sciences costs 5€. A discounted annual pass is available. Please note: preferential rate for students (discount code: PromoCDS).The booking fee includes a drink* (soft or beer), a snack (chips and cookies) and management fees linked to the organization Unless cancelled by us, bookings are non-refundable. (*additional drinks will be available upon electronic payment.)

Title of the dissertation: Ion implantation in Low-E coatings Low-emissivity (Low-E) coating technology revolutionizes glass applications for windows, offering high optical transparency while reducing heat transfer. They consist of a silver-based thin film deposited on a glass panel by physical vapor deposition. However, these coatings are fragile and must be placed inside a double-glazing cavity where an inert gas resides. Otherwise, they can be easily degraded by bad atmospheric conditions.The thesis approach is to combine low-E technology with a post-treatment of ion implantation. The research question driving this thesis is: how does ion implantation enhance the durability of low-E coatings containing silver?The experiments conducted during the thesis show that implantation indeed increases the coating resistance while having a small impact on its color. However, the treatment degrades the thermal insulation properties. Hence, a series of hypotheses are formulated based on the literature to explain and control this behavior.A deeper investigation shows that implantation impacts the silver nanostructure. First by dewetting the film which allows reorganization into larger crystallites, second by forcing silver mixing at its interface through ballistic ejections. These two phenomena increase the toughness of the silver interface by interlocking effects. However, dewetting has also been linked to thermal insulation properties degradation. Nonetheless, it was shown that using light gas implantation limits the destructive effect (dewetting) while still inducing good durability (due to interface mixing).. Jury Prof. Julien COLAUX (UNamur), presidentProf. Stéphane LUCAS (UNamur), promoter and secretaryDr Amory JACQUES (Service Public de Wallonie)Dr Philippe ROQUINY (AGC Glass Europe)Prof. Rony SNYDERS (University of Mons)

The design of collective decision-making mechanisms for robot swarms engaged in tasks that require consensus among the robots is a challenging problem in swarm robotics. The complexity of this design problem increases with the number of options and the number of cues that robots have to consider to make a decision. The research work presented in this thesis addresses this challenge by exploring the potential of evolutionary robotics (ER) as a design tool for synthesising neural network controllers that underpin the robots' decision-making process. The main objective is to design individual mechanisms that support the emergence of robust, scalable, and effective collective decision-making strategies while avoiding common assumptions made in previous research. These assumptions include pre-defined correlations between environmental features and robot behaviour or the use of specific opinion formation mechanisms, such as the voter or majority rule, to update opinions.The thesis focuses on two fundamental collective decision-making scenarios: the collective perception scenario and the site selection scenario. The first scenario involves robots collectively identifying the most prevalent element in the environment, represented by the colour covering the largest portion of the arena floor. The second scenario requires the robots to collectively choose the best site among several options based on their quality. The Faculty of Computer Science at UNamur invites you to Ahmed ALMANSOORI's PhD Thesis "On the Evolution of Mechanisms for Collective Decision-making in a Swarm of Robots". Directed by Prof. Elio TUCI.In front of a jury composed of:Prof. Wim VANHOOF, President, University of NamurProf. Elio TUCI, Promoter, University of NamurProf. Patrick HEYMANS, Internal Member, University of NamurProf. Muhanad HAYDER MOHAMMED MOHAMMED, Internal Member, University of NamurProf. Yara KHALUF, External Member, Wageningen University (Netherlands)You are cordially invited to a drink, which will follow the public defense.For good organization, please give your answer by Thursday, October 10 by means of this link.Contact: Notaro Amelie - amelie.notaro@unamur.be

Human beings have always sought to surpass the limits of their bodies. The first prosthetic foot appeared in Egypt in 600 BC. The 13th century saw the appearance of spectacles in Italy. The 17th century saw the development of various "scopes" to enhance vision of the infinitely small and the infinitely large. In the industrial sector, the 19th and 20th centuries saw the development of mechanization and then automation, with the aim of making gestures formerly performed by human hands alone faster and more precise... Not to mention all the progress accumulated over the centuries in medicine and surgery, which are also aimed at repairing or surpassing the natural limits of the human body. We agree that the field is very vast and is part of the long history of mankind... It is therefore important to target what we are talking about when we invoke the terms 'Augmented Man' and to distinguish it, despite the continuity of the project, from the innovations of the past. As philosopher Emmanuelle Perrin-Huisman (2018) points out, to speak of augmentation is first and foremost to take a quantitative rather than a qualitative viewpoint. Augmenting Man, she tells us, "is wanting to increase his longevity, his performance, his power, his power over nature and others." Then, to speak of augmented Man in the 21st century is to target augmentations that rely on nanotechnologies, biotechnologies, computer and cognitive sciences (NBIC) and their increasingly advanced convergence in projects to surpass Man's physical, cognitive or emotional limits. Finally, it also means questioning the imaginaries of immortality and technological Darwinism that are part of transhumanist currents of thought heralding the gradual emergence of a post-human individual. More information

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

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 Free - On registration The observatory is not accessible to people with reduced mobility This activity is organized with the support of Wallonie Recherche. Visit registration

Come and discover the Observatoire Astronomique Antoine Thomas, 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 to observe the beauty of our starry sky. Join the list of future visitors today! Each month, we'll be offering a one-hour evening to discover the wonders of the night sky. The dates of the evenings will be communicated to those registered according to weather conditions. To subscribe to the contact list, please fill in the form available on our website. Practical information:Guided tour and observations From 10 years old 20:00 to 21:00 and 21:00 to 22:00 Faculty of Medicine - Place du Palais de Justice, Namur Free - On registration The observatory is not accessible to people with reduced mobility This activity is organized with the support of Wallonie Recherche. Registration

Several sessions are scheduled: November 5, 12, 19 and 26 from 5pm to 7pm. Sign up