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An inquiry into Search Engine Neutrality: the case of movements against police violence in France and the U.S.
No full textInternational audienceThe digital transformation has revolutionized information consumption, with search engines playing a pivotal role in shaping user access to diverse media. Employing algorithms, these engines influence content visibility and aggregate news sources, significantly molding public opinion. As gatekeepers of information, search engines impact media outlet visibility, affecting online traffic, revenue, and journalistic diversity. In breaking news and societal issues, search engines expedite information dissemination, influencing initial narratives. Understanding their role is crucial for transparency and user access to diverse information. Focusing on movements against police violence, our paper conducts a comparative analysis across 12 search engines for terms "Black Lives Matter" and "Justice pour Adama". Our innovative methodology identifies biases in information diversity, providing insights into the dynamics shaping visibility of societal issues.</div
The polytope of all -rank functions
No full textA -rank function is a real-valued function defined on the subspace lattice that is non-negative, upper bounded by the dimension function, non-drecreasing, and satisfies the submodularity law. Each such function corresponds to the rank function of a -polymatroid. In this paper, we identify these functions with points in a polytope. We show that this polytope contains no interior lattice points, implying that the points corresponding to -matroids are among its vertices. We investigate several properties of convex combinations of two lattice points in this polytope, particularly in terms of independence, flats, and cyclic flats. Special attention is given to the convex combinations of paving and uniform -matroids
From Elements to Isotopes: Fingerprinting Consumer Plastics
No full textInternational audiencePolymer identification alone rarely informs on additive provenance or metal interactions. We tested whether multi-element profiles and selected metal isotopes provide complementary and reproducible fingerprints of consumer plastics. We analyzed 119 items spanning major polymers and colors after microwave digestion. Forty-one elements were quantified by ICP-MS; Cu, Sr, and Pb isotope ratios were measured by MC-ICP-MS on selected purified subsets. Elemental concentrations span over eight orders of magnitude (from Rare Earth Elements (REE) at µg kg⁻¹ to Ca at >10 8 µg kg⁻¹). Non-parametric statistics reveal significant polymer and color effects; polypropylene (PP) shows higher Mg, Si, Cr, and Ni than polyethylene (PE), while color modulates Cu and some REE. Strontium isotope ratios vary widely (⁸⁷Sr/⁸⁶Sr = 0.70765-0.71320), consistent with contributions from disparate mineral fillers and pigments. Copper isotopes are systematically enriched in 65 Cu with variable values (δ⁶⁵Cu = +0.18‰ to +1.35‰), supporting the influence of distinct Cu-based pigment formulations. Lead isotope ratios further discriminate legacy Pb-bearing additives observed in a subset of items, consistent with distinct manufacturing and/or recycled streams. Overall, combined elemental-isotopic fingerprints thus provide complementary, integrated and transferable markers of additive provenance beyond spectroscopic polymer identification. These signatures open new avenues for source apportionment and understanding the fate of environmental plastics
Incentives for self-isolation based on incidence rather than prevalence could help to flatten the curve: A modeling study
No full textNational audienceIn recent years, numerous advances have been made in understanding how epidemic dynamics are affected by changes in individual behaviors. We propose a Susceptible-Infected-Susceptible (SIS) based compartmental model to tackle the simultaneous and coupled evolution of an outbreak and of the adoption by individuals of the isolation measure. The compliance with self-isolation is described with the help of the imitation dynamics framework. Individuals are incentivized to isolate based on the prevalence and the incidence rate of the outbreak, and are tempted to defy isolation recommendations depending on the duration of the isolation and on the cost of putting social interactions on hold. We are able to derive analytical results on the equilibria of the model under the homogeneous mean-field approximation. Simulating the compartmental model on empirical networks, we also perform a preliminary check of the impact of a network structure on our analytical predictions. We find that the dynamics collapse to surprisingly simple regimes where either the imitation dynamics no longer plays a role or the equilibrium prevalence depends on only two parameters of the model, namely the cost and the relative time spent in isolation. Whether individuals prioritize disease prevalence or incidence as an indicator of the state of the outbreak appears to play no role on the equilibria of the dynamics. However, it turns out that favoring incidence may help to flatten the curve in the transient phase of the dynamics. We also find a fair agreement between our analytical predictions and simulations run on an empirical multiplex network
New directions for interconnector research: drawing from social sciences and humanities perspectives to explore the Celtic Interconnector
No full textInternational audienceThe current discourse on interconnectors primarily centers on the technical and economic aspects necessary for delivering a stable grid infrastructure powered by renewable sources and for integrating energy markets. This article, therefore, explores opportunities to broaden definitions of energy grid interconnectivity beyond the techno-economic sphere. It considers multidisciplinary perspectives and presents novel exploratory viewpoints from the social sciences and humanities. It examines ideas of interconnection by drawing on the Celtic Interconnector, an Irish-French initiative, to explore the cultural, historical, political, and geographical dimensions of interconnectivity. Insights are derived from two workshops with academics in Ireland and France, encouraging a more contextual understanding of energy interconnections beyond their physical and economic dimensions. The article builds on these insights to set out an agenda for future research and reflect on frames of reference for describing, analysing, and engaging with emerging interconnector processes and the multiple stakeholders involved
Refining patient selection for transcatheter tricuspid interventions: the role of the GLIDE Score in the evolving therapeutic landscape
No full textInternational audienc
Differing responses of functional and taxonomic waterbird diversity to vegetation height and water level variation in a coastal wetland
No full textInternational audienceThe conservation of wetland biodiversity is a major global issue. In anthropogenic landscapes, it requires the identification of environmental conditions and management practices that sustainably maintain the diversity of the communities. We carried out a six-year survey over 18 sites (78 ha) in the Marais Breton, lowland grazing marshes on the western coast of Europe in France. We tested the influence of the spatio-temporal dynamic of vegetation heights, water depth and the proportion of flooded areas on the taxonomic and functional diversity of wading birds and ducks at the site scale. Taxonomic diversity was enhanced by higher spatial heterogeneity of water level and reduced by higher spatial heterogeneity of vegetation height. In sharp contrast, functional diversity was not influenced by spatial heterogeneity of water level and increased with spatial heterogeneity of vegetation height. Additionally, the effect of the spatio-temporal heterogeneity of water level and vegetation height was guild-dependent. Based on our results we encourage a management at the landscape scale integrating multiple land ownerships to promote a taxonomic and functional diversity rather than at the site scale only
Mitral Annulus Calcification: Pathophysiology, Outcome, and Imaging Evaluation
No full textInternational audienceMitral annulus calcification (MAC) is a chronic, degenerative process characterized by calcium deposition in the mitral annulus. It is commonly observed in elderly individuals and those with chronic kidney disease, hypertension, and metabolic disorders. MAC has been increasingly recognized as a marker of cardiovascular disease and is associated with adverse clinical outcomes, including mitral valve dysfunction, arrhythmias, and increased cardiovascular mortality. The pathophysiology of MAC involves endothelial dysfunction, chronic inflammation, and osteogenic differentiation of valvular interstitial cells, driven by risk factors such as aging, chronic kidney disease, diabetes mellitus, and hypertension. Imaging modalities, including echocardiography and computed tomography (CT) play a crucial role in the diagnosis, assessment, and risk stratification of MAC. The presence of MAC complicates mitral valve interventions, making surgical and transcatheter approaches challenging. Despite advancements in imaging and therapeutic strategies, MAC remains a significant challenge in cardiovascular medicine, necessitating further research into its pathophysiology, optimal management strategies, and long-term outcomes
La grande enquête agricole de 1866-1870. De l'état des lieux du progrès agricole à l'expertise impériale (France-Espagne)
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The new ethical challenges raised by the authorization of elective egg freezing in France since 2021
No full textInternational audiencePurpose: Since 2021, elective egg freezing (EEF) without medical indication has been authorized and fully reimbursed in France for women aged 29 to 37. While this regulatory change represents a significant advancement in reproductive rights, it also raises new ethical and organizational challenges. This study aimed to explore the ethical issues experienced by infertility specialists involved in the clinical implementation of EEF in France.Methods: This prospective, qualitative, monocentric study was conducted in a university-based ART center. All physicians involved in EEF at the center were invited to participate in semi-structured interviews. Data were analyzed inductively using Grounded Theory methodology.Results: Eight practitioners participated. Four main themes emerged: (1) challenges in accessing EEF due to resource constraints and growing demand; (2) a new relationship between caregiver and patient in a context where care is no longer strictly medical; (3) a need to redefine the role of EEF in society, including the terminology used and funding mechanisms; and (4) questions about the future of EEF, including prioritization criteria, equitable access, and sustainability of the current model.Conclusions: While EEF is widely supported by healthcare professionals, its integration into routine practice reveals tensions between autonomy, justice, beneficence, and public resource management. National guidelines, improved access to information, and further research-particularly incorporating women's perspectives-are essential to ensure ethically sound implementation