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Propriétés et économies entre matériel et immatériel XVIe-XXIe siècle
No full textInternational audienc
Global mild solutions in a critical setting for a forced fractional Boussinesq system
No full textWe study here mild solutions for the forced, incompressible fractional Boussinesq system. Under suitable estimates for the terms involved (in an adapted functional framework) we can invoque a fixed point argument in order to obtain mild solutions. Although many functional spaces can be considered, we are interested here in a critical setting which ensures the existence of global solutions and we will work in particular with parabolic Morrey spaces which provide one of the largest critical functional frameworks available for constructing mild solutions for the fractional Boussinesq equations
Ce que l’accélération du rythme fait de nous. Réflexions à partir de Jacques Derrida
No full textInternational audienc
ELIXIR Microbiome Community – 2025 face to face/hybrid meeting report
No full textThis document reports on the agenda, key points, and outcomes of the ELIXIR Microbiome Community's face-to-face and hybrid meeting, which took place on April 9-10, 2025, in Barcelona, Spain
Comptabilité et audit de cryptoactifs : quels enjeux, pratiques et perspectives ?
No full textCet article est issu des travaux réalisés dans le cadre de la convention de recherche avec l’Autorité des NormesComptables (ANC) sur la comptabilisation de cryptoactifs, nous remercions l’ANC pour le soutien apporté.International audienceThe objective of this study is threefold: deepen the knowledge of cryptoassets, their ecosystem and their regulatory framework; discuss current accounting issues related to cryptoassets; examine the audit practices of cryptoassets in order to issue recommendations on the due diligence to be implemented by the auditor.L'objectif de cette étude est triple : approfondir les connaissances sur les cryptoactifs, leur écosystème et leurcadre réglementaire (1) ; dresser un état des lieux des règles comptables actuelles liées aux cryptoactifs (2) ; examiner les pratiques en matière d’audit des cryptoactifs et les enjeux y liés afin d’émettre des recommandations sur les diligences à mettre en œuvre par le commissaire aux comptes (3)
Synergy of energy storage and transparency in KNN-based relaxor ceramics
No full textInternational audience(K0.5Na0.5)NbO3(KNN)-based ferroelectric ceramics demonstrate significant industrial potential due to their excellent ferroelectric properties, well-established fabrication methods, and inherent optical transparency—an advantage for emerging transparent electronics. This study introduces a lead-free relaxor ferroelectric ceramic (1-x)(((K0.5Na0.5)NbO3)0.87((K0.296Bi0.9)(Zn0.667Nb0.334)O3)0.13) - x(Ca(Ti0.8Ta0.16)O3) (x = 0.02, 0.04, 0.06, 0.08), synthesized by a solid state method. This synergistic engineering approach delivers outstanding energy storage performance, achieving a recoverable energy density of up to 2.34 J/cm3 and an efficiency of 74 %, along with optical transmittance reaching ∼67 % at 1800 nm. These results set a new benchmark for developing eco-friendly transparent energy-storage ceramics
Online multivariate changepoint detection: leveraging links with computational geometry
No full textInternational audienceThe increasing volume of data streams poses significant computational challenges for detecting changepoints online. Likelihood-based methods are effective, but a naive sequential implementation becomes impractical online due to high computational costs. We develop an online algorithm that exactly calculates the likelihood ratio test for a single changepoint in p-dimensional data streams by leveraging a fascinating connection with computational geometry. This connection straightforwardly allows us to exactly recover sparse likelihood ratio statistics: that is assuming only a subset of the dimensions are changing. Our algorithm is straightforward, fast, and apparently quasi-linear. A dyadic variant of our algorithm is provably quasi-linear, being O(nlog(n)p+1) for n data points and p less than 3, but slower in practice. These algorithms are computationally impractical when p is larger than 5, and we provide an approximate algorithm suitable for such p which is O(nplog(n)p~+1), for some user-specified p~≤5. We derive statistical guarantees for the proposed procedures in the Gaussian case, and confirm the good computational and statistical performance, and usefulness, of the algorithms on both empirical data and NBA data
Does privacy regulation harm content providers? A longitudinal analysis of the impact of the GDPR
No full textFNEGE 1*, ABS 4*International audienceConcerns that the European General Data Protection Regulation (GDPR) would adversely affect the ability of news and media websites to create new quality content have not been thoroughly investigated in the literature. We construct a longitudinal data set of European Union (EU) and U.S. news and media websites to study how online content providers responded to the GDPR over time and whether potential restrictions on online tracking enforced by the regulation affected their downstream outcomes. We find robust evidence that both EU and U.S. news and media websites responded to the regulation by altering their data collection practices, but did so differently, with EU websites reducing tracking and implementing consent mechanisms at higher rates than their U.S. counterparts. Although we detect a reduction in average page views per user on EU relative to U.S. websites, we do not find evidence of negative impacts, in both the short and long term, on EU websites’ provision of new content or on several proxies for quality of that content, such as social media engagement metrics, various traffic measures, and articles’ text analytics. We also find no evidence of differences in survival rates across EU and U.S. news and media websites, and no evidence that monetization strategies changed at higher rates on EU relative to U.S. websites. The analysis suggests that EU online content providers did implement changes to their data collection practices in response to the GDPR but were able to use data minimization and consent mechanism strategies that allowed them to keep producing content and engage audiences at degrees on par with their U.S. counterparts
Existence of optimal controls for stochastic Volterra equations
No full textInternational audienceWe provide sufficient conditions that guarantee the existence of relaxed optimal controls in the weak formulation of control problems for stochastic Volterra equations (SVEs). Our study can be applied to rough processes which arise when the kernel appearing in the controlled SVE is singular at zero. The proof of existence of relaxed optimal policies relies on the interaction between integrability hypotheses on the kernel, growth conditions on the running cost functional and on the coefficients of the controlled SVEs, and certain compactness properties of the class of Young measures on Suslin metrizable control sets. Under classical convexity assumptions, we also deduce the existence of optimal strict controls
The transcription factor NF-YA10 determines the area explored by Arabidopsis thaliana roots through direct regulation of LAZY and TAC genes
No full textInternational audienceRoot developmental plasticity relies on transcriptional reprogramming, which largely depends on the activity of transcription factors (TFs). NF-YA2 and NF-YA10 (Nuclear Factor A2 and A10) are down-regulated by the specific miRNA isoform miR169defg, in contrast to miR169a. Here, we analyzed the role of the Arabidopsis thaliana TF NF-YA10 in the regulation of lateral root development. Plants expressing a version of NF-YA10 resistant to miR169 cleavage showed a perturbation in the lateral root gravitropic response. By extracting novel features of root architecture using the ChronoRoot deep-learning-based phenotyping system, we uncovered a differential emergence angle of lateral roots over time when compared to Col-0. Detailed phenotyping of root growth dynamics revealed that NF-YA10 activity modulates the area explored by Arabidopsis roots. Furthermore, we found that NF-YA10 directly regulates TAC1 and LAZY genes by targeting their promoter regions, genes previously linked to gravitropism. Hence, the TF NF-YA10 is a new element in the control of LR gravitropism and root system architecture