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The rise and fall of neoliberalism: Evidences from an ecological and regulationist analysis of France (1960–2020)
No full textInternational audienceThis article explores the critical role of energy in shaping capitalist modes of development, and their entry into crisis, in France between 1960 and 2020. This analysis challenges traditional views that regard energy primarily as an exogenous shock and instead posits energy as a fundamental metabolic constraint in capitalist accumulation regimes. To demonstrate this, we integrate energy flows into the analysis of capitalists' regimes by crossing two bodies of knowledge: ecological economics and regulation theory. We enrich regulation theory with three key ecological macroeconomics indicators: thermodynamic efficiency, exosomatic metabolic rate and the weight of energy expenditures. Using descriptive statistics, we show that the weight of energy expenditures is the most significant variable: it must be contained if the rate of profit is to be maintained and if capital accumulation is to continue. Neoliberalism responded to the metabolic exhaustion of Fordism but eventually encountered its own limits in managing energy constraints. Neoliberal recipes for reconfiguring the metabolism have generated major imbalances likely to call into question the reproduction of this regime (financial crises, trade imbalances). We conclude that neoliberalism's structural crisis is rooted in the exhaustion of past energy management strategies, opening the door to the emergence of post-liberal capitalism
What is personalized lung poromechanical modeling and how can it improve the understanding and management of fibrotic interstitial lung diseases?
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Streaming Platforms, Filter Bubbles, and Cultural Inequalities. How Online Services Increase Consumption Diversity
No full textInternational audienceDo digital technologies affect diversity in cultural tastes? Digital sociologists have warned of “filter bubbles,” whereas sociologists of culture have shown that diversity in consumption is valued as a marker of upper-middle-class status. We estimate the effect of using streaming platforms on the diversity of cultural consumption using a matching technique applied to 2018 survey data from France. We find a statistically significant positive effect of using streaming platforms on the diversity of cultural consumption as well as on cosmopolitanism, on three domains, music, movies, and TV shows. The magnitude of this effect is much higher for TV shows. The study brings new evidence against the filter bubble thesis; it shows that platforms do reinforce cultural inequalities by increasing the social gap in consumption diversity. It further suggests that the effect of technology on cultural consumption might mainly operate through its impact on cultural markets rather than changes in cultural experience
Representing improved tropospheric ozone distribution over the Northern Hemisphere by including lightning NO x emissions in CHIMERE
No full textInternational audienceAbstract. Estimating nitrogen oxide emissions from lightning (LNOx) in models is highly uncertain, affecting the accuracy of atmospheric composition and air quality assessments. Still, it is essential to include these emissions in models to increase the realism of representing the gases and aerosols. LNOx emissions have recently been incorporated into the updated version of the CHIMERE model (v2023r2). In this study, we evaluate the present state of modelling the lightning flashes over the Northern Hemisphere (NH), using a classical scheme based on cloud-top height (CTH) and an updated ice-flux-based scheme (ICEFLUX). We conduct a comprehensive 3D comparison of model outputs, including in situ measurements and satellite data, to rigorously assess the robustness and applicability of these parameterizations. The comparative analysis reveals that the CTH scheme provides a more accurate spatial variability of lightning flashes over lands and tropical oceans. Both parameterizations accurately capture the magnitude of lightning flashes over the tropics, while the ICEFLUX scheme is more effective in representing mid-latitudinal flashes. However, both schemes perform well in capturing the seasonal variation of lightning flashes. The estimated flash frequencies over the NH from the experiments closely align with satellite observations, and the LNOx emissions fall within the range reported in previous modelling studies. There is an overall increase in ozone (O3) concentration due to inclusion of LNOx, which substantially improves the tropospheric O3 distribution, specifically in the tropical free troposphere. The LNOx emissions hence critically influence the O3 burden as well as the hydroxyl radicals, which further impact the atmospheric lifetime of trace gas methane
Measurement of branching fractions and asymmetries in decays
No full textInternational audienceA study of and baryon decays to the final states and is performed using collision data collected by the LHCb experiment, corresponding to an integrated luminosity of . The decays and are observed for the first time, with significances reaching eight standard deviations. The branching fractions and integrated asymmetries are measured for the , , and decays. For the decay , the asymmetries are measured in different regions of the Dalitz plot. No evidence of violation is observed
Online Combinatorial Allocation with Interdependent Values
No full textInternational audienceWe study online combinatorial allocation problems in the secretary setting, under interdependent values. In the interdependent model, introduced by Milgrom and Weber (1982), each agent possesses a private signal that captures her information about an item for sale, and the value of every agent depends on the signals held by all agents. Mauras, Mohan, and Reiffenhäuser (2024) were the first to study interdependent values in online settings, providing constant-approximation guarantees for secretary settings, where agents arrive online along with their signals and values, and the goal is to select the agent with the highest value.In this work, we extend this framework to combinatorial secretary problems, where agents have interdependent valuations over bundles of items, introducing additional challenges due to both combinatorial structure and interdependence. We provide 2e-competitive algorithms for a broad class of valuation functions, including submodular and XOS functions, matching the approximation guarantees in the single-choice secretary setting. Furthermore, our results cover the same range of valuation classes for which constant-factor algorithms exist in classical (non-interdependent) secretary settings, while incurring only an additional factor of 2 due to interdependence. Finally, we extend our study to strategic settings, and provide a 4e-competitive truthful mechanism for online bipartite matching with interdependent valuations, again meeting the frontier of what is known, even without interdependence
A New Prognostic Parameterization of Subgrid Ice Supersaturation and Cirrus Clouds in the ICOLMDZ AGCM
No full textInternational audienceA new cirrus cloud parameterization for the ICOLMDZ atmospheric general circulation model (AGCM) is presented. Prognostic equations for cloud fraction, ice water content and cloudy water vapor are introduced, and the processes that affect these quantities are parameterized. In particular, the tendency in ice crystal mass concentration due to changes in water phases is calculated, as is the macroscale mixing of cirrus clouds with their environment. The parameterization simulates ice supersaturation in clear sky, an ubiquitous metastable phenomenon in the upper troposphere that is necessary for the formation of in situ cirrus clouds. Our parameterization also allows for cirrus clouds to be sub-and supersaturated with respect to ice. It is evaluated on a case study of a warm conveyor belt cirrus cloud forming and dissipating above the Paris region. The representation of high cloud cover is improved with the new parameterization relative to the default version of the cloud scheme in comparison to observations, as is the representation of water vapor. In particular, the upper tropospheric dry bias from ICOLMDZ is corrected, although it is replaced by a wet bias in some cases. Global simulations show similar results. Contrarily to the default parameterization, ice water content and high cloud cover can be tuned separately, but the ice fall velocity parameter, that controls the intensity of ice autoconversion, remains the most determining parameter controlling the overall ice water content.</div
Synthesis of Diarylmethanes by Cobalt-Catalyzed Reductive Cross-Coupling via Csp3–S Bond Activation
No full textInternational audienceAbstract Various diarylmethane derivatives were synthesized by cobalt-catalyzed cross-electrophilic coupling of benzylsulfonium salts with various aryl bromides in moderate to good yields. This simple protocol exhibited good tolerance for various functional groups. We demonstrated that low-valent cobalt was able to activate both aryl halides and C–S bonds from stable benzyl sulfonium salts, readily available from alcohols. Preliminary mechanistic studies suggested the involvement of benzyl radicals generated from C–S bond cleavage through a single electron transfer
A Systematic Search for MeV-GeV Pulsar Wind Nebulae without Gamma-ray Detected Pulsars
No full textInternational audienceAn increasing number of pulsar wind nebulae (PWNe) are being identified in the TeV band by ground-based Imaging Air Cherenkov Telescopes such that they constitute the dominant source class of Galactic TeV emitters. However, MeV-GeV PWN counterparts are still largely lacking. To date, only a dozen PWNe are identified by the Fermi-Large Area Telescope (LAT) in the MeV-GeV band. Most PWNe are located along the Galactic plane embedded within the prominent, diffuse Galactic gamma-ray emission, which makes these sources difficult to disentangle from the bright diffuse background. We present a systematic search for gamma-ray counterparts to known PWNe in the 300MeV-2TeV energy band using the Fermi-LAT. We target locations of previously identified PWNe that lack detected Fermi-LAT pulsars to minimize associated pulsar contamination. The sample includes 6 previously identified Fermi-LAT PWNe and 8 Fermi-LAT sources associated with PWNe. We report the analysis of 58 regions of interest and classify detected sources as either a likely PWN or a candidate PWN counterpart based on their morphological and spectral characteristics across the broadband spectrum. There are 9 unidentified Fermi-LAT sources that we consider as likely PWN counterparts, which, if confirmed to be PWNe, would greatly increase the PWN population detected by the Fermi-LAT from 12 to 21. The remaining Fermi-LAT detected sources are considered weaker PWN candidates. A second approach in the systematic search for gamma-ray emitting PWNe will involve studying the off-pulse phases of Fermi-LAT pulsars for the presence of an obscured PWN and will be reported in a subsequent paper
Hot off the Press: First Steps Towards a Runtime Analysis When Starting With a Good Solution
No full textInternational audienceThe mathematical runtime analysis of evolutionary algorithms traditionally regards the time an algorithm needs to find a solution of a certain quality when initialized with a random population. In practical applications it may be possible to guess solutions that are better than random ones. We start a mathematical runtime analysis for such situations. We observe that different algorithms profit to a very different degree from a better initialization. We also show that the optimal parameterization of an algorithm can depend strongly on the quality of the initial solutions. To overcome this difficulty, self-adjusting and randomized heavy-tailed parameter choices can be profitable. Finally, we observe a larger gap between the performance of the best evolutionary algorithm we found and the corresponding black-box complexity. This could suggest that evolutionary algorithms better exploiting good initial solutions are still to be found. These first findings stem from analyzing the performance of the (1 + 1) evolutionary algorithm and the static, self-adjusting, and heavy-tailed (1 + (λ,λ)) genetic algorithms on the OneMax benchmark. We are optimistic that the question of how to profit from good initial solutions is interesting beyond these first examples.This paper for the hot-off-the-press track at GECCO 2025 summarizes the work [1]