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From Wisconsin Institutionalism to American Macroeconomics: The Issue behind Unemployment Insurance (1910-1940) in the United States
No full textInternational audienceSocial policy has been a field of analytical and political debates during the New Deal. While historians of economic thought have studied this period in depth, the field of social policy has been somehow neglected. This paper focuses on the quarrel (as it was named by US American historians) which occurred during the genesis of unemployment insurance in the United-States during the 1930's. This historical debate opposes Wisconsin's Institutionalism led by John R. Commons and a diffuse group composed of reformers and economists developing some "Keynesian elements" in American thought. The paper argues that, while there is clearly a link between Commons and Keynes's thinking, the fact is that on the specific subject of employment, Commons charts his own course and advocates a "structural supply-side policy" centered on institutional reform in the implementation of unemployment insurance in the United-States.We highlight the lessons from this debate that took place among advocates of social security, revealing two conceptions of the social control of capitalism and two institutional designs for unemployment assurance. By completing the historiography of this period, the paper challenges the conventional wisdom by arguing that the New Deal in social policy does not really embody Commons' specific philosophy and economics
Er3+-doped (Lu,Y,Sc)2O3 mixed sesquioxide crystal fiber: Fabrication and spectroscopic characterization
No full textInternational audienceAbstract: Er3+-doped (Lu,Y,Sc)2O3 mixed sesquioxide crystal fiber, along with Lu2O3, Y2O3,and Sc2O3 crystal fibers were fabricated using the laser-heated pedestal growth (LHPG) method.XRD characterization revealed that Er:(Lu,Y,Sc)2O3 crystal fiber maintains a single-phasecubic structure with the Ia-3 space group. The absorption and emission spectra, along withfluorescence lifetimes, were systematically investigated. Judd-Ofelt (JO) analysis wasemployed to determine the spontaneous emission probabilities, branching ratios, and radiativelifetimes. The material exhibits an absorption cross-section of 2.12×10−21 cm2 at 983 nm, withemission cross-sections reaching 0.90×10−20 cm2 at 2742 nm (4I11/2 → 4I13/2 transition) and0.93×10−20 cm2 at 1558 nm (4I13/2 → 4I15/2 transition). The measured fluorescence lifetimes were1.04 ms for the 4I11/2 upper laser level and 5.76 ms for the 4I13/2 lower level. These resultshighlight the promising potential of Er:(Lu,Y,Sc)2O3 crystal fibers for 2.7 μm laser applications
Renaming in distributed certification
No full textInternational audienceLocal certification is the area of distributed network computing asking the following question: How to certify to the nodes of a network that a global property holds, if they are limited to a local verification? In this area, it is often essential to have identifiers, that is, unique integers assigned to the nodes. In this short paper, we show how to reduce the range of the identifiers, in three different settings. More precisely, we show how to rename identifiers in the classical local certification setting, when we can (resp. cannot) choose the new identifiers, and we show how a global certificate can help to encode very compactly a new identifier assignment that is not injective in general, but still useful. We conclude with a number of applications of these three results
Going beyond ‘predation’ and ‘survival’: The importance of demographic changes for understanding snowshoe hare cycles
No full textInternational audienceEcologists have long been intrigued by cycles in population abundances characterizing the dynamics of some wild species. Abundance may follow surprisingly regular cycles, with an increase phase, a peak phase and then a decline phase of more or less the same length. Predator‐induced mortality has long been proposed as the main demographic mechanism inducing population cycles, leading most of cycle theory to consider that population cycles result from survival changes only. In this paper, Oli et al. (2025) assessed how the cycles in population abundance of the snowshoe hare ( Lepus americanus ) in Yukon, observed during 43 years, are driven by survival or reproductive rates of some specific age classes and how their contributions differ according to the cyclic phase. Thanks to the individual monitoring of more than 7000 snowshoe hares and a state‐of‐the‐art capture‐mark‐recapture modelling framework, they showed different contributions of age‐specific vital rates to the population growth rate, depending on the cyclic phase (increase, peak, decline and low phases) and the breeding period considered (early, mid, late and non‐breeding periods). For instance, improved breeding probability, litter size and pre‐weaning survival played a major role during the increase phases, whereas lower pre‐weaning survival explained population decline. They also highlighted a strong interaction between season and cyclic phases, with, for example, at mid‐breeding season, a survival in low phases that is close to the survival observed in increase phases. This led to different life‐history strategies over the seasons and the phases: the population had a fast strategy in the early breeding season in the increase phase and a slow strategy in the late breeding season and decline phase, demonstrating a high level of plasticity across phases and seasons. The enigma of population cycles is not fully solved yet, but the study by Oli et al. (2025) clearly contributes to improving our mechanistic understanding of population cycles
Reconstruct Anything Model: a lightweight foundation model for computational imaging
No full textInternational audienceMost existing learning-based methods for solving imaging inverse problems can be roughly divided into two classes: iterative algorithms, such as plug-and-play and diffusion methods leveraging pretrained denoisers, and unrolled architectures that are trained end-to-end for specific imaging problems. Iterative methods in the first class are computationally costly and often yield suboptimal reconstruction performance, whereas unrolled architectures are generally problem-specific and require expensive training. In this work, we propose a novel non-iterative, lightweight architecture that incorporates knowledge about the forward operator (acquisition physics and noise parameters) without relying on unrolling. Our model is trained to solve a wide range of inverse problems, such as deblurring, magnetic resonance imaging, computed tomography, inpainting, and super-resolution, and handles arbitrary image sizes and channels, such as grayscale, complex, and color data. The proposed model can be easily adapted to unseen inverse problems or datasets with a few fine-tuning steps (up to a few images) in a self-supervised way, without ground-truth references. Throughout a series of experiments, we demonstrate state-of-the-art performance from medical imaging to low-photon imaging and microscopy. Our code is available at https://github.com/matthieutrs/ram
Euclid preparation. Non-Gaussianity of 2-point statistics likelihood: Precise analysis of the matter power spectrum distribution
No full textInternational audienceWe investigate the non-Gaussian features in the distribution of the matter power spectrum multipoles. Using the COVMOS method, we generate 100 000 mock realisations of dark matter density fields in both real and redshift space across multiple redshifts and cosmological models. We derive an analytical framework linking the non-Gaussianity of the power spectrum distribution to higher-order statistics of the density field, including the trispectrum and pentaspectrum. We explore the effect of redshift-space distortions, the geometry of the survey, the Fourier binning, the integral constraint, and the shot noise on the skewness of the distribution of the power spectrum measurements. Our results demonstrate that the likelihood of the estimated matter power spectrum deviates significantly from a Gaussian assumption on nonlinear scales, particularly at low redshift. This departure is primarily driven by the pentaspectrum contribution, which dominates over the trispectrum at intermediate scales. We also examine the impact of the finiteness of the survey geometry in the context of the Euclid mission and find that both the shape of the survey and the integral constraint amplify the skewness
Determinants of successful completion and short-term benefits associated with temporary alcohol abstinence during Dry January in France: A prospective cohort study
No full textInternational audienceObjective: Temporary alcohol abstinence campaigns (TAAC), such as Dry January, aim to encourage behavioural change in the general population. Despite its popularity, a comprehensive evaluation of the French version has not yet been conducted. This prospective study aimed to identify characteristics associated with successful completion of the challenge (i.e., remaining alcohol-free throughout January), and to assess improvements in drinking refusal self-efficacy, sleep quality, and mental and physical health.Methods: A sample of 2123 French adults participating in Dry January 2024 completed both a baseline and a one-month follow-up questionnaire online. A broad range of variables were assessed, including demographic and contextual factors, alcohol use patterns and motives, drinking refusal self-efficacy, and health-related outcomes.Results: Key factors positively associated with successful completion included previous participation, registration, and higher baseline self-efficacy in resisting alcohol in social situations. Among registrants, greater engagement with support emails significantly increased the likelihood of abstinence. In contrast, smoking and identifying one's drinking as excessive were linked to lower odds of completion. The campaign was associated with improvements in drinking refusal self-efficacy, mental well-being, sleep quality, and physical health - particularly among participants who completed the full month without alcohol.Conclusions: This study offers the first evaluation of the French version of Dry January, highlighting the factors influencing challenge completion and short-term benefits of participation. The findings add support to the value of TAAC as scalable and impactful public health tools and underscore the importance of tailored support strategies to maximize participant success and behavioural change
Aux origines des écosystèmes entrepreneuriaux : L’entrepreneuriat, modèles d’organisation d’hier à aujourd’hui
No full textInternational audienceCe chapitre propose de revenir sur les origines, l’évolution et l’importance actuelle des écosystèmes entrepreneuriaux en plongeant au cœur de l’évolution des dynamiques entrepreneuriales, s’éloignant progressivement de la figure solitaire de l’entrepreneur pour embrasser la notion plus vaste et intégrative de l’écosystème entrepreneurial
Organization of French level 1 adult trauma centers: A national survey
No full textInternational audienceThe specialized care of acute trauma patients is increasingly organized within networks, with the most critical patients referred to level 1 trauma centers (TC1). This French national survey aimed to evaluate the organizational and structural characteristics of these centers