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The Interplay of Public and Private Debts: Evidence on Business Cycles and Growth
No full textPrivate credit and public debt levels have reached unprecedented levels in many economies. This paper examines their joint dynamics over multiple horizons, focusing on a sample predominantly composed of high-and upper-middle-income countries with relatively mature financial systems. Using disaggregated data on debt recipients from 1970 to 2018, the analysis shows that treating private credit and public debt in isolation masks important interactions. At the business cycle frequency, credit-intensive expansions are a key precursor to financial distress and slower recoveries, with high public debt at the onset of a crisis further amplifying these effects by constraining fiscal space. At the medium-run horizon, the results are consistent with a trade-off between the growth benefits of financial deepening and rising macro-financial vulnerabilities: private credit supports growth at lower levels of financial development, but its contribution diminishes-and can turn negative-as economies become more financially advanced. The adverse effects of private credit surges are compounded by high public debt, offering new insight into why financial expansion may fail to sustain long-term growth under certain macroeconomic conditions. This adverse medium-run association is largely conditional on crisis episodes and credit composition, particularly household credit
ENTRE MYTHE ET PHARMACIE : PEUT-ON CROIRE AU REISHI ?
No full textInternational audienceBetween myth and pharmacy: can we trust Reishi?Ganoderma lucidum (Reishi/Lingzhi) is a flagship species of traditional Asian medicines and is increasingly marketed worldwide as an “adaptogenic” dietary supplement. However, the taxonomic accuracy and scientific validity of products sold under this name remain questionable. We conducted a literature survey (PubMed, 2010–2025) and a taxonomic reassessment of ITS sequences deposited in GenBank as G. lucidum (n = 814), complemented by our own taxonomic and pharmacochemical studies. Although 69% of publications on Ganoderma claim to investigate G. lucidum, the main research topics concern its purported pharmacological properties: immunomodulatory and anticancer effects (34%), metabolic and cardiovascular disorders (12%), neuroprotection and anti-aging (3%). These activities are commonly attributed to bioactive metabolites such as polysaccharides, triterpenes and phenolic compounds. However, only 0.5% of the published sequences actually match G. lucidum sensu stricto, mostly of European origin. The vast majority correspond to closely related Asian species, mainly G. sichuanense (= G. lingzhi), for which chemical and biological data remain limited. In total, at least 27 different species are marketed or studied under the name “Reishi”.Our results highlight that morphology alone cannot ensure the authenticity, composition or expected effects of Ganoderma-based supplements. Genetic authentication should become a standard requirement for both scientific studies and industrial products. Regulatory frameworks for Reishi must rely on accurate species identification to guarantee product quality and consumer safety.Le Reishi (Ganoderma lucidum), champignon emblématique des médecines traditionnelles asiatiques, connaît un essor commercial majeur en tant que complément alimentaire dit « adaptogène ». Toutefois, la fiabilité des produits vendus sous ce nom reste discutée. Nous avons conduit une analyse de la littérature scientifique (PubMed, 2010-2025) et une révision taxonomique des séquences ITS déposées dans GenBank sous l’appellation G. lucidum (n = 814), complétées par nos propres travaux en taxonomie et pharmacochimie. Si 69 % des publications sur Ganoderma prétendent étudier G. lucidum, ces recherches se concentrent principalement sur ses effets pharmacologiques : immunomodulation et anticancéreux (34 %), maladies métaboliques et cardiovasculaires (12 %), neuroprotection et vieillissement (3 %). Ces propriétés sont attribuées à divers métabolites bioactifs (polysaccharides, triterpènes, composés phénoliques). Néanmoins, seules 0,5 % des séquences publiées correspondent réellement à G. lucidum sensu stricto, majoritairement européen. La très grande majorité relève en réalité d’espèces asiatiques proches, notamment G. sichuanense (= G. lingzhi), pour lesquelles les données chimiques et biologiques demeurent lacunaires. Ainsi, au moins 27 espèces différentes sont impliquées sous le nom « Reishi ».Nos résultats soulignent l’insuffisance des critères morphologiques pour garantir l’identité et l’activité des produits commercialisés. Une authentification génétique systématique des souches étudiées ou utilisées industriellement est indispensable. Une réglementation du marché du Reishi doit s’appuyer sur une identification précise des espèces afin d’assurer la qualité et la sécurité des consommateurs
Lagrange’s Three Methods and Langrangean in Maxwell’s A Treatise on Electricity and Magnetism (1873)
No full textInternational audienc
La délinquance des enfants : quelles responsabilités pour quelles réponses ?: Rapport de synthèse
No full textInternational audienc
Emotional Content of Social Representations and Interpersonal Communication
No full textInternational audienc
Environmental Evaluation of Geopolymer Bricks Containing Phase Change Materials - A State-of-the-Art Review
No full textInternational audienceThe construction industry is a major contributor to global carbon emissions, primarily due to the energy-intensive production of traditional fired bricks. This study presents a comparative analysis between conventional and geopolymer bricks enhanced with phase change materials (PCMs), focusing on environmental, thermal, mechanical, and economic performance. Geopolymer bricks, synthesized from industrial by-products such as fly ash and PET waste, eliminate the need for high-temperature kiln firing, resulting in up to 80% lower CO₂ emissions[1]. The integration of PCMs further enhances their thermal regulation capabilities by absorbing and releasing heat, stabilizing indoor temperatures, and reducing energy consumption in buildings[2]. Life Cycle Assessment (LCA) confirms these traditional bricks offer a significantly smaller environmental footprint. Mechanically, geopolymer bricks maintain high compressive strength and durability, even with PCM inclusion[3]. Economically, they are cost-effective due to reduced energy use and the availability of low-cost raw materials[4]. Overall, geopolymer bricks with PCMs represent a sustainable, high-performance alternative to traditional bricks, aligning with global climate goals and offering a viable solution for energy-efficient and environmentally responsible construction
Counter-Resistant Digital Communities: The Impact of Truth Social in a Fragmented Society
No full textInternational audienceIn today’s digital landscape, social media platforms serve as central spaces for political communication and community building. However, the growing fragmentation of information has fostered ideological polarization and the emergence of closed environments, such as Truth Social, launched by Donald Trump following his exclusion from traditional channels. Focusing on the U.S. case, this study examines how Truth Social functions as a refuge for groups perceived as isolated from mainstream discourse, offering a context of cultural and political “resistance” that often conveys identitarian and exclusionary visions. The article explores communicative dynamics and the construction of political identity within this alternative digital space, where the algorithm rewards engagement regardless of the reliability of the content. The result is a progressive radicalization, fuelled by echo chambers and filter bubbles that strengthen internal cohesion and limit democratic dialogue. Through an illustrative comparative reading of significant posts published by Trump on Truth Social, X, Instagram, and TikTok during the 2024 presidential campaign, the study highlights differences in tone, political purpose, and rhetorical strategies. While Truth Social fosters a direct, intimate, and polarizing communication with Trump’s electoral base, the other platforms reveal a more strategic and performative use of language. The text technically emphasizes how Truth Social is not merely a distribution tool but rather a true space of ideological belonging, contributing to the formation of closed communities and the radicalization of public opinion. The article thus offers a critical reflection on the role of alternative platforms in reshaping the public sphere and the democratic implications of growing digital segmentation
Risk and uncertainty of mobility in the digital age: (In)security(ies) and non-knowledge at the EU’s borders
No full textInternational audienceThe increased use of biometric data, national and European databases and artificial intelligence to manage migration in Europe has created new uncertainties for exiles. While studies on security have focused mainly on the way in which states manage ‘border’ or ‘migration’ risks, this article examines exiles’ representations of the risks of mobility by comparing them with those produced by institutions in Europe. Using qualitative analysis of institutional documents and interviews with policymakers, NGOs, and exiles in France and Germany, the study questions what the unknowns or non-knowledge, inherent to datafication tools in border governance, produce on the perception of risk of migration candidates. While the institutions focus on controlling ‘migration’ and ‘terrorist’ threats, exiles see the risk of mobility as both a necessary survival strategy and a danger of deprivation of fundamental rights, while coming to relativise the lethal risks increasingly present at the EU’s borders. Although each actor has his or her own perspective, whether border police officer or exile, the rationality of control tends to standardise risk prevention practices, which at the same time produce more confusion and uncertainty. Thus, the study of the production of uncertainty and non-knowledge demonstrates its central role in the dynamics of power and governance at borders, which is achieved to the detriment of both exiles and the security at EU’s border