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Consumer Information and the Cybernetic Control of Markets: A Model Explored in the Beauty Market
No full textInternational audienceThe unprecedented access to consumer information through digital technologiesseems to have had two unrelated consequences on markets for final goods. It has been usedto enhance product innovation and accelerate commodity circulation. Building on a multi-disciplinary literature on these phenomena, from marketing and management to industrialeconomics, this article proposes to model them as “feedback processes” that complementone another to allow markets to expand and profit to be accumulated. We explore thishypothesis in a qualitative study of the beauty market, which shows the tight relationshipbetween devices operationalizing innovation and circulation
Quantum properties of NV centers in diamond: towards optimized industrial protocols
No full textInternational audienceBecause of their high sensitivity, quantum materials are extremely promising for new technologies. The main challenge lies in maintaining a sufficiently quantum coherence times for quantum computation or quantum sensing systems. NV centers in diamond which are point defects consisting of a substitutional nitrogen atom neighboring an atomic vacancy, where an electron pair can reside in a triplet state – are ideal candidates for the development of industrial-scale quantum systems. These spin states exhibit ms-long coherence times at room temperature and can be manipulated optically, hence opening interesting perspectives for sending magnetic fields with high sensitivity1.At HiQuTe Diamond, we take up the challenge of mastering the entire nitrogen-doped diamond production chain synthesized by Microwave Plasma-Assisted Chemical Vapor Deposition (MPACVD). We aim at creating affordable diamonds specially engineered to achieve long coherence times with high NV density and high doping uniformity. This quest require to overcome the impact of several external factors that contribute to electron spin decoherence. First, the chemical composition of the diamond, specifically the types and concentrations of impurities within the diamond matrix (such as substitutional nitrogen NS, NV centres, mono-vacancies and clusters, hydrogen, etc.), as well as their electrical charge states (NS⁰, NS⁺, NV⁰, NV⁻) should be carefully controlled. Thanks to extensive scientific research conducted over the past decade, combined with our own R&D efforts, we are now able to quantify these parameters using experimental techniques compatible with industrial applications (Raman and UV-Vis spectroscopy) and compare our results with key performance indicators2. Second, we study the relationship between coherence (T2*) and strain inhomogeneities in our diamond layers, which we analyse using birefringence measurements. Our findings demonstrate our capability to produce CVD diamond layers with reduced strain and extended defect and confirm that strain could be a critical limiting factor for T2*.In this poster, I will review the efforts carried out at HiQuTe Diamond to develop specific material that is well suited for quantum sensing applications.References1.Barry, J. F., Schloss, J. M., Bauch, E., Turner, M. J., Hart, C. A., Pham, L. M., & Walsworth, R. L. (2020). Sensitivity optimization for NV-diamond magnetometry. Reviews of Modern Physics, 92(1), 015004.2.Langer, J. (2022). Quantum-grade diamond for cavity-based solutions. Fraunhofer Verlag
Credibility assessment of a mechanistic model of atherosclerosis to predict cardiovascular outcomes under lipid-lowering therapy
No full textInternational audienceDemonstrating cardiovascular (CV) benefits with lipid-lowering therapy (LLT) requires long-term randomized clinical trials (RCTs) with thousands of patients. Innovative approaches such as in silico trials applying a disease computational model to virtual patients receiving multiple treatments offer a complementary approach to rapidly generate comparative effectiveness data. A mechanistic computational model of atherosclerotic cardiovascular disease (ASCVD) was built from knowledge, describing lipoprotein homeostasis, LLT effects, and the progression of atherosclerotic plaques leading to myocardial infarction, ischemic stroke, major acute limb event and CV death. The ASCVD model was successfully calibrated and validated, and reproduced LLT effects observed in selected RCTs (ORION-10 and FOURIER for calibration; ORION-11, ODYSSEY-OUTCOMES and FOURIER-OLE for validation) on lipoproteins and ASCVD event incidence at both population and subgroup levels. This enables the future use of the model to conduct the SIRIUS programme, which intends to predict CV event reduction with inclisiran, an siRNA targeting hepatic PCSK9 mRNA
Asymptotic blow-up behavior for the semilinear heat equation with non scale invariant nonlinearity
No full textWe characterize the asymptotic behavior near blowup points for positive solutions of the semilinear heat equation \begin{equation*} \partial_t u-\Delta u =f(u), \end{equation*} for nonlinearities which are genuinely non scale invariant, unlike in the standard case . Indeed, our results apply to a large class of nonlinearities of the form , where p>1 is Sobolev subcritical and is a slowly varying function at infinity (which includes for instance logarithms and their powers and iterates, as well as some strongly oscillating functions). More precisely, denoting by the unique positive solution of the corresponding ODE which blows up at the same time , we show that if is a blowup point of , then \begin{equation*} \lim_{t\to T}\frac{u(a+y\sqrt{T-t},t)}{\psi(t)}= 1,\quad \text{uniformly for bounded.} \end{equation*} Additional blow-up properties are obtained, including the compactness of the blow-up set for the Cauchy problem with decaying initial data
Design of control laws to meet generalized mutual exclusion constraints in a network of timed event graphs with disturbances using dioid algebra.
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How does hospital organisation influence the use of intrapartum caesarean sections in low-and middle-income countries? A cross-sectional survey in Argentina, Burkina Faso, Thailand and Vietnam for the QUALI-DEC project
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Isolated singularities of solutions of a 2-D diffusion equation with mixed reaction
No full textInternational audienceWe study the local properties of positive solutions of the equation -∆u + ae bu = m |∇u| q in a punctured domain Ω \ {0} of R 2 where m, a, b are positive parameters and q > 1. We study particularly the existence of solutions with an isolated singularity and the local behaviour of such singular solutions.</div
How to manage antivirals in critically ill patients with influenza?
No full textInternational audienceBackground: Influenza is a significant cause of morbidity and mortality, particularly in critically ill patients. The availability of effective antiviral therapies is pivotal in mitigating the severity and complications associated with influenza.Objectives: This review evaluates the antivirals available for the treatment of severe influenza in critically ill patients, focusing on the strength of recommendations and levels of evidence derived from clinical trials, observational studies, and guidelines. The aim is to provide clinicians with evidence-based insights to optimize antiviral strategies in the intensive care unit setting.Sources: A comprehensive literature search was conducted using PubMed, Embase, and Cochrane Library databases for studies published up to January 2025. Keywords included "antiviral therapy," "influenza," "critically ill patients," "oseltamivir," "peramivir," "zanamivir," "lanimavir," "baloxavir," and "favipiravir." Additional references were identified from the bibliographies of relevant articles.Content: The following topics are covered: antivirals available for treating influenza and evidence supporting their use in critically ill patients, pharmacokinetic issues of enteral oseltamivir administration in critically ill patients, and neuraminidase inhibitors resistance. Implications: Neuraminidase inhibitors constitute the vast majority of antivirals currently prescribed for influenza. The most commonly prescribed neuraminidase inhibitor to date is oseltamivir. Although its efficacy in nonsevere cases of influenza is well established, the evidence for its efficacy in critically ill patients is based on less robust studies, as no randomized controlled trials have been conducted in this population. Limited data on oseltamivir pharmacokinetics is available in critically ill patients. The selection of A(H1N1)pdm09 resistant variants to oseltamivir is particularly problematic in critically ill patients hospitalized in intensive care units. Data on other antivirals, such as neuraminidase inhibitors (i.e. zanamivir, peramivir and laninamivir) or baloxavir marboxil in critically ill patients are scarce. Further research is needed to develop new drugs and assess their efficacy in critically ill patients and to better assess the effect of oseltamivir in this population
Corps super-héroïques et regards queers : Réceptions comparées des productions Marvel et DC par les publics français et états-uniens
No full textThis dissertation explores the relationships between audiences and the portrayals of diversity—particularly queer representations—within the Marvel and DC universes. It compares how these works are received in France and the United States by fan communities and LGBTQIA+ audiences. The study highlights complex and often conflicting reception processes related to gender and sexuality, revealing tensions and mutual misunderstandings between audiences and producers that go beyond a binary conflict between supporters and oppositionists. The research is based on an initial online questionnaire, disseminated through fan pages and LGBTQIA+ associations, followed by a series of interviews conducted between 2022 and 2023. Audience receptions are further examined through ethnographic observations of online practices (fan pages, fandoms, fanfiction, social media) and in-person events (notably during festivals). In parallel, a representative corpus of works (comics, films, series) was analyzed to assess how hegemonic narratives are critically received and to identify potential marginal or oppositional readings. Following an overview of production methods and the historical evolution of media— providing insight into national differences in reception—this dissertation investigates the emotional, intellectual, and cultural dimensions of the participants’ experiences. The chapters focus on their relationships with superhero narratives, from initial discovery of the genre to the various forms of negotiated or oppositional appropriation they develop, as well as the diverse uses they make of these texts. The aim is first to analyze the place these figures occupy in their cultural universe, and then to examine how superhero stories contribute to their identity construction and how they shape their relationship to the works themselves. Finally, the last chapter sheds light on the strategies of circumvention adopted in response to the limitations of identification, those representations being sometimes called out as articificial by the audience.Cette thèse explore les relations qu’entretiennent les publics avec les mises en scène de la diversité, et plus particulièrement des représentations queers, dans les univers Marvel et DC. Elle compare les réceptions de ces œuvres en France et aux États-Unis par des publics fans et LGBTQIA+. L’étude met en lumière des processus de réception liés au genre et à la sexualité, complexes et conflictuels, qui dépassent l’opposition binaire entre défense et rejet, révélant tensions et incompréhensions mutuelles entre publics et producteur·ice·s. L’enquête s’appuie sur un premier questionnaire en ligne, diffusé via des pages de fans et des associations LGBTQIA+, suivi d’une série d’entretiens menés entre 2022 et 2023. Ces réceptions sont également éclairées par une ethnographie des pratiques en ligne (pages de fans, fandoms, fanfictions, réseaux sociaux) et de terrain (notamment lors de festivals). En parallèle, un corpus représentatif d’œuvres (comics, films, séries) a été analysé afin d’étudier la réception critique des publics face aux narratifs hégémoniques et d’identifier d’éventuelles lectures minorées. Après un détour par l’évolution des méthodes de production et par l’histoire des médiums — permettant notamment de mieux comprendre les différences nationales de réception —, cette thèse s’intéresse aux dimensions émotionnelles, intellectuelles et culturelles des parcours des enquêté·e·s. Les chapitres se concentrent sur leur relation aux œuvres de super-héros, depuis la découverte du genre jusqu’aux formes de réappropriation négociées ou oppositionnelles qu’iels développent face à ces récits, en passant par les multiples usages produits par ces publics. Il s’agit d’abord d’analyser la place que ces figureso ccupent dans leur univers culturel, puis d’examiner comment les récits superhéroïques participent à la construction de leur identité et façonnent leur rapport aux œuvres elles-mêmes. Enfin, le dernier chapitre met en lumière les stratégies de contournement mises en œuvre face aux limites inhérentes à l’identification, liées à des représentations perçues comme artificielles
Computing Improved Explanations for Random Forests: k-Majoritary Reasons
No full textInternational audienceThis work focuses on improving explanations for random forests, which, although efficient and providing reliable predictions through the combination of multiple decision trees, are less interpretable than individual decision trees. To improve their interpretability, we introduce k-majoritary reasons, which are minimal implicants for inclusion supporting the decisions of at least k trees, where k is greater than or equal to the majority of the trees in the forest. These reasons are robust and provide a better explanation of the forest’s decision. However, due to their large size and our cognitive limitations, they may be too hard to interpret. To overcome this obstacle, we propose probabilistic majoritary explanations, which provide a more concise interpretation while maintaining a strict majority of trees. We identify the computational complexity of these explanations and propose algorithms to generate them. Our experiments demonstrate the effectiveness of these algorithms and the im provement in interpretability in terms of size provided by probabilistic majoritary explanations (δprobable majoritary reasons)