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Earthquake Source Spectra and Site Attenuation in Northwestern France
No full textInternational audienceABSTRACT Northwestern France is a stable continental region submitted to a high rate of low-to-moderate-magnitude earthquakes for which source characteristics are not well known. The deployment of permanent seismological networks during the last decade allows, for the first time in this region, to study their source spectra to determine their seismic moment M0, associated magnitude Mw, corner frequency fc, and stress drop Δσ. In France, two national agencies, RéNaSS and CEA-LDG, provide local magnitudes. The spectra of 108 events of 2.0≤MLRéNaSS≤5.3 that occurred between 2015 and 2024 are analyzed in the frequency range [0.01–50] Hz under the assumption of an omega-square source model. The effect of attenuation on fc is tested by correcting the observations with two different absorption-band models, and an empirical parameter κ‾0 is assessed at each station to account for the near-site loss of energy above ∼5 Hz. Linear relationships MLRéNaSS∝1.13Mw−0.21 and MLLDG∝1.20Mw−0.19 are obtained for 1.7≤Mw≤5.0. A Brune Δσ in the range [5.4–9.4] MPa is derived for the largest magnitude (Mw 5) of the data set, which is similar to results obtained in other intraplate regions. When combined with the M0−fc relations, the regressions between local magnitudes and Mw indicate that the slope of the MLLDG−Mw relation is governed by attenuation effects, whereas the MLRéNaSS−Mw relation may be explained either by attenuation effects or by an increase of Δσ with M0. However, a more precise description of the attenuation is required before concluding about a possible deviation from self-similarity between small- and large-magnitude earthquakes
Du spa nordique à la retraite en pleine nature : le Québec au coeur de la révolution du tourisme de bien-être
No full textThis article, published in The Conversation, highlights the growth and challenges of wellness tourism in Quebec, a trend that addresses the search for reconnection and meaning in a world driven by an accelerated pace of life. Drawing on Hartmut Rosa’s concept of “resonance,” the article shows how wellness tourism practices (Nordic spas, forest retreats, meditation, thermotherapy, etc.) aim to slow things down and re-center visitors on their bodies and surroundings.Quebec stands out for its vast and diverse natural environment, its climate favoring hot-cold contrasts, and its adaptation of the Scandinavian model to the local context. Beyond simple relaxation, these offerings are part of a holistic approach that involves both psychological balance and the valorization of natural resources and regional economic vitality. Despite promising growth, the sector remains loosely structured and faces challenges such as the lack of official certification, the need for well-trained professionals, and the sustainable management of fragile sites. Nevertheless, the article emphasizes that this “gentle revolution” is not merely a passing fad; it reflects a profound shift in the way people travel and perceive well-being, where slowing down and connecting with nature become essential antidotes to the over-stimulation of modern life.Il s’agit d’un article publié dans The Conversation qui met en lumière la croissance et les enjeux du tourisme de bien-être au Québec, une tendance qui répond à la quête de reconnexion et de sens dans un monde soumis à un rythme de vie accéléré. S’appuyant sur le concept de « résonance » (Hartmut Rosa), l’article montre comment les pratiques de tourisme de bien-être (spas nordiques, retraites en forêt, méditation, thermothérapie, etc.) visent à ralentir la cadence et à recentrer les visiteurs sur leur corps et leur environnement.Le Québec se démarque par sa nature vaste et diversifiée, ses conditions climatiques favorisant le contraste chaud-froid, et l’adaptation du modèle scandinave au contexte local. Outre la simple détente, ces offres s’inscrivent dans une logique holistique qui engage tout autant l’équilibre psychologique que la valorisation des ressources naturelles et la vitalité économique des régions. Malgré cette dynamique prometteuse, le secteur reste peu structuré et fait face à des défis comme l’absence de certification officielle, le besoin de former des professionnels qualifiés et la gestion durable de sites fragiles. Toutefois, l’article souligne que cette « révolution douce » ne se réduit pas à une mode : elle traduit un changement profond dans la manière de voyager et de percevoir le bien-être, où l’expérience de la lenteur et de la connexion à la nature devient un antidote essentiel à la sursollicitation de la vie moderne
Tracing the Origin and Evolution of the Fungal Mycophenolic Acid Biosynthesis Pathway
No full textInternational audienceLike bacteria and plants, fungi produce a remarkable diversity of small molecules with potent activities for human health known as natural products or secondary metabolites. One such example is mycophenolic acid, a powerful immunosuppressant drug that is administered daily to millions of transplant recipients worldwide. Production of mycophenolic acid is restricted to a very limited number of filamentous fungi, and little is known about its biosynthetic modalities. It is therefore a particular challenge to improve our knowledge of the biosynthesis of this valuable natural compound, as this would contribute to a better understanding of the specialized metabolism of fungi and could also lead to the identification of new fungal producers for the supply of immunosuppressants. Here, we were interested in deciphering the origin and evolution of the fungal mycophenolic acid biosynthetic pathway. Large-scale analyses of fungal genomic resources led us to identify several new species that harbor a gene cluster for mycophenolic acid biosynthesis. Phylogenomic analysis suggests that the mycophenolic acid biosynthetic gene cluster originated early in a common ancestor of the fungal family Aspergillaceae but was repeatedly lost and it is now present in a narrow but diverse set of filamentous fungi. Moreover, a comparison of the inosine 5′-monophosphate dehydrogenase protein sequences that are the target of the mycophenolic acid drug as well as analysis of mycophenolic acid production and susceptibility suggest that all mycophenolic acid fungal producers are resistant to this toxic compound, but that this resistance is likely to be based on different molecular mechanisms. Our study provides new insight into the evolution of the biosynthesis of the important secondary metabolite mycophenolic acid in fungi
Ultra-trail : ce que révèle la science sur ce sport extrême
No full textInternational audienceThis popular science article, published in The Conversation under the title “Ultra-trail: What Science Reveals About This Extreme Sport,” reports on a groundbreaking study conducted during a 156 km ultra-trail in Clécy (Suisse normande, France). The aim was to observe, in 56 runners, the combined effects of fatigue, sleep deprivation, and prolonged exertion on physiological, psychological, and social dimensions.The research protocol included continuous monitoring of core temperature via a swallowed gastrointestinal capsule, blood glucose through subcutaneously implanted sensors, biomechanical parameters of running gait (using shoe-mounted sensors), as well as heart and respiratory rates. Cardiac ultrasound tests (led by a team at the Caen University Hospital) and various evaluations (muscular fatigue, alertness, balance assessments in virtual reality) provided deeper insights into this phenomenon. Findings show that ultra-trail performance hinges on a combination of factors: robust cardiorespiratory capacity, muscular endurance, careful pace and nutrition management, mental steadiness, and effective sleep strategies.Beyond the physiological perspective, the study also revealed a strong existential component. Trail running in nature fosters a profound sense of connection to one’s environment and heightened bodily awareness, as measured notably by the State Mindfulness Scale. This increased somatic consciousness, coupled with a drive for self-transcendence, helps explain the discipline’s growing popularity.In conclusion, this investigation opens up new avenues for research—by exploring the complex interplay between physiology and psychology—as well as for practitioners, who are encouraged to tailor their training individually, prioritize recovery, and remain alert to risky behaviors. It underscores the necessity of a multidisciplinary lens to grasp the full scope of ultra-trail, a genuine open-air laboratory positioned between athletic achievement and an introspective, transformative experience.Cet article grand public, publié dans The Conversation sous le titre « Ultra-trail : ce que révèle la science sur ce sport extrême », rend compte d’une étude inédite menée lors d’un ultra-trail de 156 km à Clécy (Suisse normande). L’objectif était d’observer, chez 56 coureurs, les effets combinés de la fatigue, de la privation de sommeil et de l’effort prolongé sur le plan physiologique, psychologique et social.Le protocole a consisté en un suivi continu de la température centrale (gélule gastro-intestinale), de la glycémie (capteurs implantés sous-cutanés), des paramètres biomécaniques de la foulée (capteurs positionnés sur les chaussures) ainsi que de la fréquence cardiaque et respiratoire. Des tests d’échographie cardiaque (équipe du CHU de Caen) et plusieurs évaluations (fatigue musculaire, vigilance, équilibre en réalité virtuelle) ont permis d’approfondir la compréhension du phénomène. Les résultats montrent à quel point la performance en ultra-trail repose sur une combinaison d’aptitudes : robustesse cardio-respiratoire, endurance musculaire, gestion de l’allure et de l’alimentation, équilibre mental et bonne gestion du sommeil.Au-delà des aspects physiologiques, l’enquête fait apparaître une forte composante existentielle : la course en pleine nature favorise un profond sentiment de connexion à l’environnement et de présence à soi, mesuré notamment par la State Mindfulness Scale. Cette conscience corporelle accrue, ainsi que la recherche d’un dépassement de soi, explique en partie la popularité grandissante de la discipline.En conclusion, l’étude offre de nouvelles perspectives tant pour la recherche (exploration des interactions complexes entre physiologie et psychologie) que pour les pratiquants (importance de l’individualisation de l’entraînement, de la récupération et de la vigilance vis-à-vis des pratiques à risque). Elle illustre la nécessité d’un regard pluridisciplinaire pour comprendre l’ultra-trail, véritable laboratoire à ciel ouvert, à la frontière entre prouesse sportive et expérience introspective
Proteomic analysis of liver fibrosis reveals EFEMP1 as a new modulator of focal adhesion and migration of hepatic stellate cells
No full textInternational audienceLiver fibrosis is characterized by an excessive accumulation of extracellular matrix (ECM) leading to liver dysfunction. Proteomic approaches help to decipher ECM alterations during fibrosis progression. Using a decellularization method, we performed a proteomic analysis of 18 fibrotic human liver samples and identified 106 deregulated ECM proteins. Three members of the fibulin protein family (fibulin‐2, ‐3, and ‐5) expressed by hepatic stellate cells were significantly associated with fibrosis progression. Integrative analyses of protein–protein interaction networks highlighted different functional annotations for these three fibulins. Gene silencing studies showed that unlike fibulin‐2 (FBLN2), fibulin‐3 (EFEMP1) depletion impaired focal adhesions, FAK phosphorylation, the fibronectin network, and cell migration. These findings are the first to demonstrate the critical involvement of fibulin‐3 in the regulation of hepatic stellate cell focal adhesions and migration, emphasizing the intricate link between chronic liver disease progression and remodeling of the microenvironment
Monocation vs Dication 2D → 1D Dimensional Reduction Agent Affording Broad Band Emitters 1D Lead Bromide Perovskites
No full textInternational audienceThe synthesis, crystal structures and optical properties of the 2D perovskite (Cyst)PbBr4 (1) and two 1D perovskite hybrids Cs(Cyst)PbBr5 (2) and (Cyst)2PbBr5,Br (3) based on the cystaminium dication (Cyst2+) exhibiting a helical chiral conformation are described in this work. The 1D compounds can be conceptually described from the 2D mother structure by the dimensional reduction concept. Thus, the addition of one CsBr unit to one (Cyst)PbBr4 leads to Cs(Cyst)PbBr5 (2), whose structure can be described as organic-inorganic sheets [(Cyst)PbBr5] - separated by Cs+ monocation in the inter-sheet space, while the addition of one (Cyst),2Br unit to one (Cyst)PbBr4 leads to (Cyst)2PbBr5,Br (3) whose structure can be described as organicinorganic sheets [(Cyst)PbBr5] -separated by Cyst2+ dications and free bromides in the inter-sheet space. The acentric compound (2) crystallizing in the P21 space group exhibits SHG properties, while the three compounds emit light when excited in the UV-visible domain. The 2D compound exhibits two close excitonic narrow peaks in the blue region, certainly resulting from bulk and edges states as already observed. In contrast, the lower dimensional compounds (2) and (3) have a broad band emission type covering a good part of the visible range, illustrating the interest of such low dimensional 1D compounds compared to 2D mother compounds for white light type emission
Strengthening Data Privacy and Interconnectivity of a Digital Twins Prototype: Application to a Heat Pump
No full textInternational audienceDigital Twins (DT) have become a groundbreaking technology in the industrial field. They provide numerous advantages that improve security strategy, sustainability, and decision-making quality. DT enable real-time monitoring, simulation, and optimization by creating virtual replicas of physical assets, leading to significant performance and resource management improvements. Adopting industrial Digital Twins encounters various research challenges that inhibit their seamless incorporation into the industrial environment. These gaps mainly focus on DT security and the requirement for improved interconnectivity for DT assets. Tackling these challenges is essential for maximizing the benefits of digital twins in Industry 4.0. Throughout our research, we identified the capabilities of the OPC UA Protocol in terms of interconnectivity and data privacy, allowing it to function as a bridge between industrial protocols for SCADA and conventional TCP/IP Protocols, thus facilitating the hosting of a DT in the cloud. Established on the Six-Step DT Design Framework outlined in the literature and aligned with the specifications of the International Organization for Standardization (ISO) standards on Digital Twins, we have developed a prototype of a Digital Twin for a geothermal Heat Pump (GeoHP DT Prototype) using the Node-RED platform. However, DT also presents numerous challenges, such as cybersecurity and real-time data transmission, which remain significant hurdles to widespread adoption in the industry.</div
Frugal Innovation and Entrepreneurial Identity in Morocco : Strategies for Resilience in Resource-Constrained Contexts
No full textInternational audienceFrugal innovation, characterized by its ability to create impactful solutions using minimalresources, has gained significant traction as a transformative approach in emergingmarkets. This study delves into the intersection of frugal innovation and entrepreneurialidentity within the Moroccan context, where resource constraints and socio-economiccomplexities demand adaptive and resilient business practices. Drawing from the onionmodel of identity, this research examines how entrepreneurs creatively navigate layeredidentities—cultural, familial, linguistic, and regional—to foster innovation, adapt toshifting economic landscapes, and overcome structural and institutional barriers.Employing an ethnographic approach centered on an in-depth interview with thefounder of MadNess, a Moroccan creative collective, this study explores howentrepreneurs leverage informal networks, cultural capital, and social ties to co-createvalue. MadNess serves as a prime case study of frugal innovation, exemplifying howlimited access to resources can inspire ingenuity in building sustainable, culturallyrelevant solutions. Through the lens of the founder’s lived experiences, the researchhighlights strategies such as repurposing available materials, tailoring solutions to meetlocal needs, and fostering grassroots collaborations that bridge gaps between formaland informal ecosystems.Findings emphasize the critical role of frugal innovation in empowering Moroccanentrepreneurs to navigate the dual economy—a hybrid environment of formal regulatorysystems and informal business practices. By embedding innovation within their socio-cultural contexts, these entrepreneurs demonstrate exceptional resilience and creativity,reshaping conventional notions of resource utilization and market engagement. Thestudy contributes to the growing discourse on everyday entrepreneurship in emergingmarkets, particularly by illuminating how frugal innovation not only enables businesssustainability but also promotes social inclusion and cultural preservation.This research advocates for the integration of frugal practices into policy frameworksand entrepreneurial support programs to strengthen inclusive ecosystems. Itunderscores the need to reimagine entrepreneurship as a culturally embedded practicethat thrives on adaptability, resourcefulness, and a deep understanding of localcontexts. Through its focus on ethnographic insights, the study provides a rich, nuancedunderstanding of how identity, culture, and innovation converge to shapeentrepreneurial resilience in Morocco’s dynamic business landscape. Ultimately, thiswork highlights the transformative potential of frugal innovation in fostering equitableand sustainable entrepreneurial ecosystems in the face of global and local challenges
