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The Future of Whale Conservation: Harnessing Distributed Acoustic Sensing for Real-Time Monitoring
No full textInternational audienceWhale distribution is a key indicator of ocean health and ecosystem stability, highlighting the need for informed conservation efforts. Yet, current monitoring methods such as visual surveys or autonomous passive acoustic monitoring, lack the spatial and temporal resolution necessary for detailed and continuous surveys at scale.Distributed Acoustic Sensing (DAS) is a game-changing innovative technology that transforms optical fibers into a dense network of sensors for geophysical and acoustic measurements. By emitting laser pulses propagating along the fiber, DAS detects signals reflected back from various points along the cable, providing high-resolution spatial data, over tens of kms. At the cost of massive amounts of data that require fast, optimized algorithms, this technology can operate on any optical fiber, including the hundreds of telecom cables already crisscrossing the world’s oceans.In this presentation, we will illustrate how DAS implemented on seafloor cables along the French Mediterranean coast enables whale detection and localization. This innovative project aims to track the presence, migration patterns, and locations of whales, contributing valuable insights into their behavior and movement patterns. Moreover, with the ability to collect and process data in real-time opens up the possibility of sharing the cetacean locations with relevant stakeholders, including nearby vessels.This information can enable vessel operators to adjust their speed, thereby reducing the risk of collisions and protecting marine mammals from the impacts of human activities
Insight into rifampicin resistance behind discordant mutations in RpoB of Mycobacterium tuberculosis: A molecular dynamics simulations study
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Single-photon detection enabled by negative differential conductivity in moiré superlattices
No full textInternational audienceDetecting individual light quanta is essential for quantum information, space exploration, advanced machine vision, and fundamental science. In this work, we introduce a single-photon detection mechanism using highly photosensitive nonequilibrium electron phases in moiré materials. Using tunable bands in bilayer graphene/hexagonal boron nitride superlattices, we engineer negative differential conductance and a sensitive bistable state capable of detecting single photons. Operating in this regime, we demonstrate single-photon counting at mid-infrared (11.3 micrometers) and visible wavelengths (675 nanometers) and temperatures up to 25 kelvin. This detector offers prospects for broadband, high-temperature quantum technologies with complementary metal-oxide semiconductor compatibility and seamless integration into photonic-integrated circuits. Our analysis suggests that the underlying mechanism originates from superlattice-induced negative differential velocity
Penser à partir des pratiques improvisées en danse ou repenser la subjectivité et l'événement en philosophie : Vers une nouvelle approche de la créativité artistique
No full textIn the collective imagination, improvisation is generally associated with various forms of lack: a lack of organization and order, of effort and rigor, of technique and mastery. Likewise, it has often been discredited, if not entirely dismissed, within philosophy, which on this point does not appear to have clearly distinguished itself from popular opinion. Considered a scarcely philosophical topic—and putting aside the differences that do exist between everyday improvisation and deliberately artistic improvisation—it has often been criticized for its supposedly diminished artistic value. The improviser is said to deceive their audience by adopting the guise of a brilliant artist struck by sudden inspiration, while merely concealing a lack of skill, style, and creativity. This thesis aims to challenge that perspective by revaluing improvised practices, focusing on the relatively understudied case of dance. It takes as a starting point the practices of American postmodern dance in the 1960s and 70s, which, for the first time, conceived of and practiced improvisation for its own sake, rather than reducing it to the embellishment of a movement or to novel material intended for the composition of a later choreography. In what way does the lack of reference points that an improviser intentionally seeks, not hinder creativity, but on the contrary, open the door to a new approach to artistic creativity? In attempting to answer this question, this work proposes to think “from within” improvised practices themselves—that is, to draw from lived experience and the testimonies of improvisers, understood as “situated” and “embodied knowledge”—in order to develop a philosophical theory of improvisation in dance. We believe that while philosophical methods and tools can help articulate what is at stake when a dancer improvises, improvisational practices, in turn, help us rethink our philosophical concepts. Given this framework, the first phase of our research analyzes the improviser's creative spontaneity, which necessitates a depersonalized expression of their gestures—that is, a stepping back from the ego in order to open oneself to the unpredictable. This stands in contrast to the traditional view that an artist invests something of themselves in their creations and expresses themselves personally through their work. This withdrawal of the ego leads, in various ways, to a certain deconstruction of individual subjectivity: through an action that places will—understood as the driving force of the body and as a form of control over a situation—in a secondary position, in order to embrace the idea of “willing the involuntary”; through ways of making and unmaking the body that soften the distinctive features of a “proper body”; and through an openness to forces of action that are not solely one's own, revealing the transindividual dimension inherent in all improvisations. This line of thought leads us, in a second phase, to consider the shift from I to We, from the individual to the collective, where we discover that if there is transcendence in any artistic creation—as something always inevitably escapes full control—then this transcendence takes on different forms within the collective creativity that gives rise to an improvisation. This transcendent character is not the result of a divine inspiration or innate predispositions, but rather of the excess or surplus that arises in the present moment from the individual actions of the improvisers and their interactions. We propose to call this “more-than” an event—an emergent phenomenon that renders certain moments of highly successful improvisation particularly magical—and which, through its relational and durational dimensions, opens the way to a new possible approach to the notion of the event in philosophy.Dans l'imaginaire collectif, l'improvisation est généralement associée à un manque aux formes multiples : un manque d'organisation et d'ordre, de travail et de rigueur, de technique et de maîtrise. De même, elle a été souvent discréditée sinon omise en philosophie laquelle sur ce point ne semble pas dès lors s'être nettement distinguée de la doxa populaire. Considérée comme un objet peu philosophique et abstraction faite des différences qui pourtant existent entre l'improvisation au quotidien et une improvisation délibérément artistique, elle a ainsi souvent été critiquée au regard de sa valeur artistique prétendument dégradée, car l'improvisateur illusionnerait son public en se donnant de faux airs d'un artiste génial qui serait en proie à une inspiration subite, alors qu'il ne ferait que dissimuler de cette façon son manque de savoir-faire, de style, de créativité. Cette thèse se propose de prendre le contrepied de cette acception pour revaloriser les pratiques improvisées, en prenant le cas de la danse qui a été relativement peu étudié, et en repartant des pratiques offertes par la danse postmoderne états-unienne des années 60 et 70 laquelle, pour la première fois, pense et pratique enfin l'improvisation pour elle-même sans la réduire à l'embellissement d'un geste ou à un matériau inédit servant l'écriture d'une chorégraphie ultérieure. En quoi le manque de repères qu'un improvisateur recherche intentionnellement ne ruine pas toute créativité mais au contraire ouvre la voie à une nouvelle approche de la créativité artistique ? Dans la tentative de répondre à cette question, nous proposons dans ce travail de penser « à partir des » pratiques improvisées elles-mêmes, c'est-à-dire de partir de notre expérience vécue ainsi que des témoignages des improvisateurs, comme « savoirs situés » et « incarnés », pour tenter d'élaborer une théorie philosophique de l'improvisation en danse. Nous croyons effectivement que si la méthode et les outils philosophiques peuvent aider à expliciter ce qui est en jeu quand un danseur improvise, les pratiques d'improvisation nous aident en retour à repenser nos concepts philosophiques. Ce cadre étant donné, le premier moment de notre recherche analyse la spontanéité créatrice de l'improvisateur qui rend nécessaire une expression dépersonnalisée de ses gestes, c'est-à-dire une mise à distance de son ego pour s'ouvrir à l'imprévisible, alors qu'il est traditionnellement reconnu qu'un artiste met du sien dans ses créations et s'exprime personnellement à travers ses œuvres. Cette mise en retrait de l'ego conduit de plusieurs manières à une certaine déconstruction de sa subjectivité individuelle : à travers une action qui secondarise la volonté comprise comme force motrice du corps et comme emprise sur une situation pour accepter de « vouloir l'involontaire », à travers des modes de faire et défaire son corps qui viennent nuancer les traits distinctifs d'un « corps propre », et à travers une ouverture à des forces d'agir autres que simplement miennes qui témoignent de l'aspect transindividuel de toute improvisation. Ce propos nous invite dans un second moment à envisager le passage du Je au Nous, de l'individuel au collectif, où nous y découvrons que si transcendance il y a par définition dans toute création artistique, car quelque chose échappe résolument, cette transcendance prend d'autres aspects dans la créativité collective qui sert à composer une improvisation. Ce caractère transcendant n'est pas dû à une inspiration divine ou à des prédispositions innées, mais à la surenchère, au surcroît qui émerge, sur le moment présent, des actions individuelles des improvisateurs et de leurs interactions. Nous proposons d'appeler ce « plus que » un événement qui prend la forme d'une émergence, qui rend particulièrement magiques certains moments d'improvisations très réussis et qui, dans ses aspects relationnels et durationnels, ouvre la voie à une nouvelle approche possible de l'événement en philosophie
Class conditional conformal prediction for multiple inputs by p-value aggregation
No full textInternational audienceConformal prediction methods are statistical tools designed to quantify uncertainty and generate predictive sets with guaranteed coverage probabilities. This work introduces an innovative refinement to these methods for classification tasks, specifically tailored for scenarios where multiple observations (multi-inputs) of a single instance are available at prediction time. Our approach is particularly motivated by applications in citizen science, where multiple images of the same plant or animal are captured by individuals. Our method integrates the information from each observation into conformal prediction, enabling a reduction in the size of the predicted label set while preserving the required class-conditional coverage guarantee. The approach is based on the aggregation of conformal p-values computed from each observation of a multi-input. By exploiting the exact distribution of these p-values, we propose a general aggregation framework using an abstract scoring function, encompassing many classical statistical tools. Knowledge of this distribution also enables refined versions of standard strategies, such as majority voting. We evaluate our method on simulated and real data, with a particular focus on Pl@ntNet, a prominent citizen science platform that facilitates the collection and identification of plant species through user-submitted images
L’accueil de nouveau-nés évacués de Mayotte : tensions et redéfinition des pratiques et identités professionnelles en néonatologie à La Réunion
No full textInternational audienceDue to overcrowding at the neonatal unit in Mayotte, newborn babies are sometimes transferred to hospitals on Reunion Island, another French overseas territory. These transfers are by air via the EVASAN medical evacuation system. This article is based on research conducted in a Reunion neonatology ward that receives transferred newborns, accompanied or not by their mothers. The article explores the impact on the practices and professional identities of nurses and nursery auxiliaries. These new patients arrive in a ward with limited resources, resulting in an increased workload. The presence of the mothers is deemed necessary for the well-being of the children. However, their being there introduces a social dimension to the hospital. This creates ethical tensions and blurs professional boundaries within a context where these patients are not considered a priority. It is also assumed that their care will be temporary.En raison de la saturation du service de néonatologie du centre hospitalier de Mayotte, il arrive que des nouveau-nés de parents résidant à Mayotte soient transférés dans un centre hospitalier de La Réunion, par le dispositif d’évacuation sanitaire EVASAN. Cet article repose sur une recherche de terrain dans un service de néonatologie de La Réunion. Il explore les effets de l’accueil de ces nouveau-nés évacués, accompagnés ou non de leur mère, sur les pratiques et les identités professionnelles des infirmières et auxiliaires puéricultrices. L’arrivée de ces nouveaux publics, dans un service peu outillé pour les accueillir dans de bonnes conditions, se traduit par une surcharge de travail. La présence des mères, si elle est jugée nécessaire pour le bien-être de l’enfant, fait entrer la question du social à l’hôpital, engendrant tensions éthiques et brouillage des rôles professionnels, dans un contexte où ces publics apparaissent non prioritaires et où leur accueil est perçu comme provisoire
Renal tubular epithelial cells, hRPTEC-TERT1, as an effective in vitro repeated exposure model to evaluate low-dose uranium toxicity
No full textUranium is an environmentally ubiquitous radioactive heavy metal. Its widespread use in various civilian and military activities contributes to its redistribution in the environment and increases the risk of exposure. Since the specific radiological activity of natural uranium is low, it mainly causes chemical toxicity. Epidemiological and experimental studies have shown that exposure to this radionuclide can have multiple adverse health effects, particularly on the kidney, one of its main target organs [1]. However, the mechanisms of renal toxicity, especially in the case of chronic or repeated low-dose exposure, remains incompletely understood [2]. To fill these gaps, we have decided to adopt an experimental approach using models of increasing complexity ranging from human in vitro renal models (hRPTEC cell line and kidney organoids) to an in vivo murine model with a chronic uranium exposure (ANR BioCUBK). The hRPTEC-TERT1 cells, being a reference model of proximal tubule epithelial cells [3], the first stage of the project was to develop a protocol enabling functional differentiation of these cells and their repeated/chronic exposure to low doses of uranium. We observed that hRPTEC cultured for up to 14 days without passage, adopted a characteristic semi-three-dimensional dome-shape conformation and expressed specific markers of renal tubular epithelial phenotype and tubular function. The hRPTEC cells were then exposed to uranium for 8 days, with medium changes every 2-3 days. Under these conditions and using either 10µM, 100µM or 200µM uranium, no necrotic cell death was detected. Gene expression assays allowed to examine markers of mitochondrial integrity (MFN1/2, TFAM), oxidative stress (NOX4, NQO1, SOD2, CAT), and inflammation (TNF-α, IL-6, MCP-1, CXCL8) at different time points (days 2, 5 and 8) and uranium concentrations (10µM, 100µM and 200µM). In addition, protein array screening enabled to confirm the induction of biomarkers of inflammation pathways such as the NFκB-dependent one, and accumulation of autophagic biomarkers LC3-II and p62. Finally, we were also able to study functional alteration of proximal tubule cells by measuring γ-GT activity and its incidence on previous phenotypic markers.In conclusion, chronic low-dose exposure to uranium induces mitochondrial dysfunction associated with oxidative stress and inflammation events similar to acute exposure. Future analyses in more complex models (organoids and mouse) will help us to gain integrative knowledge of potential renal adverse effects. This work will contribute to a better assessment of the risk of renal pathologies associated with chronic low-dose uranium exposure and to the identification of potential biomarkers, useful for prevention strategies and therapeutic approaches
Roadmap: Emerging Platforms and Applications of Optical Frequency Combs and Dissipative Solitons
No full textThe discovery of optical frequency combs (OFCs) has revolutionised science and technology by bridging electronics and photonics, driving major advances in precision measurements, atomic clocks, spectroscopy, telecommunications, and astronomy. However, current OFC systems still require further development to enable broader adoption in fields such as communication, aerospace, defence, and healthcare. There is a growing need for compact, portable OFCs that deliver high output power, robust self-referencing, and application-specific spectral coverage. On the conceptual side, progress toward such systems is hindered by an incomplete understanding of the fundamental principles governing OFC generation in emerging devices and materials, as well as evolving insights into the interplay between soliton and mode-locking effects. This roadmap presents the vision of a diverse group of academic and industry researchers and educators from Europe, along with their collaborators, on the current status and future directions of OFC science. It highlights a multidisciplinary approach that integrates novel physics, engineering innovation, and advanced researcher training. Topics include advances in soliton science as it relates to OFCs, the extension of OFC spectra into the visible and mid-infrared ranges, metrology applications and noise performance of integrated OFC sources, new fibre-based OFC modules, OFC lasers and OFC applications in astronomy
The horse cardiac transcriptome: Moving towards a molecular understanding of atrial fibrillation
No full textInternational audienceAbstract Background High recurrence rates after atrial fibrillation (AF) treatment may be driven by myocardial changes induced by the arrhythmia itself. Understanding the molecular mechanisms behind these changes is crucial for developing targeted therapies and improving outcomes. Objectives To characterise the cardiac transcriptome of healthy horses and explore transcriptional changes associated with persistent AF (naturally occurring and tachypacing‐induced). Study Design Case–control study. Methods RNA ‐sequencing was performed on atrial and ventricular tissue samples collected from six horses with naturally occurring persistent AF (lasting 2–12 weeks) and six healthy controls. Differential gene expression and pathway enrichment analyses were conducted to identify chamber‐specific differences and molecular pathways associated with AF . Findings were integrated with proteomic data and compared with transcriptional changes in a separate cohort of 10 horses with tachypacing‐induced AF . Atrial metabolic remodelling was further investigated by evaluating the activity of AMP ‐activated protein kinase ( AMPK ), a central metabolic regulator and measuring local glycogen content. Results The transcriptomes of the four heart chambers had distinct molecular identities. Expression of ion channels and genes encoding calcium handling proteins was largely similar to humans, despite important differences in the ventricular expression of repolarising potassium channels. Persistent AF was associated with minimal ion channel changes but significant upregulation of metabolic, fibrotic and myofibrillar pathways. Metabolic remodeling included upregulation of fatty acid and glycolytic pathways, increased glycogen content in the left atrium and preserved AMPK activity in the right atrium. Transcriptomic profiles of naturally occurring persistent AF correlated well with those of tachypacing‐induced AF . Main Limitations The study cannot distinguish changes predisposing to AF from those caused by it. Conclusion Persistent AF was associated with changes in metabolic and fibrotic pathways in the atria, with minimal ion channel remodeling. Targeting these pathways, rather than focusing solely on the electrical disturbance, may improve treatment outcomes in equine AF
Estimating sound pressure levels from distributed acoustic sensing data using 20 Hz fin whale calls
No full textInternational audienceDistributed acoustic sensing (DAS) is a promising technology for underwater acoustics, but its instrumental response is still being investigated to enable quantitative measurements. We use fin whale 20 Hz calls to estimate the conversion between DAS-recorded strain and acoustic pressure. Our method is tested across three deployments on varied seafloor telecommunication cables and ocean basins. Results show that after accounting for well-established DAS response factors, a unique value for water compressibility provides a good estimate for the conversion. This work represents a significant step forward in characterizing DAS for marine monitoring and highlights potential limitations related to instrument noise floor