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On board French imperial liners: Four transformative shades of intimacy in the Age of Steam
No full textInternational audienceThis article explores how ocean liners operated by the Compagnie des Messageries Maritimes became critical yet underexplored spaces where colonial and personal intimacies were renegotiated among first-class passengers. Positioned as imperial interstices, these ships served as liminal spaces where dominant social norms were tested and personal boundaries redefined. Drawing on travel accounts and company archives, the study reveals how the constrained environment of maritime crossings disrupted passengers’ sensory experiences and reshaped their intimate relationships – with themselves, each other and colonial hierarchies. Ships were arenas for voyeurism, political manoeuvring, and the reinforcement of racial and social divisions, functioning as both schools of domesticity and introductions to the colonial Other. They were also sites of health anxieties and mental distress, where practitioners diagnosed ‘anxious melancholy’ linked to the colonial journey. Ultimately, these crossings profoundly transformed passengers’ private lives, preparing and altering them long before they reached colonial shores
Exploration of Engagement and Interaction Patterns with Virtual vs Human Influencers: A 24-Month Comparison of Two Breton Personalities
No full textInternational audienceVirtual influencers, defined as computer-generated personas operated by creative teams, are reshaping influencer marketing, yet their reception compared to human influencers remains uncertain. While studies conducted in several countries suggest that novelty may stimulate engagement, evidence from the breton context, where authenticity and proximity are central evaluative criteria, remains limited. This exploratory study compares, over a 24month period, the performance of a virtual influencer and a human influencer with comparable audience size and thematic focus. Results show no statistically significant difference in engagement, including likes, comments and interaction rate. However, user interactions with the virtual influencer display slightly more polarized reactions, although negative comments remain extremely rare overall. These findings suggest that virtual influencers may integrate into the Breton digital landscape without clearly outperforming or underperforming human influencers. The study contributes to contextualizing virtual influencer effects in Europe and highlights the need for controlled experimental research to further examine the roles of authenticity and technological innovation.</div
Nonparametric simulation of multivariate extreme events via spectral bootstrap
No full textInternational audienceInference in extreme value theory (EVT) relies on a limited number of extreme observations, making estimation challenging. To address this limitation, we propose a nonparametric simulation scheme, the multivariate extreme events spectral bootstrap simulation procedure, relying on the spectral representation of multivariate generalized Pareto-distributed random vectors. Unlike standard bootstrap methods, our approach preserves the joint tail behavior of the data and generates additional synthetic extreme data, thereby improving the reliability of inference. We demonstrate the effectiveness of our procedure on the estimation of tail risk metrics, under both simulated and real data. The results highlight the potential of this method for enhancing risk assessment in high-dimensional extreme scenarios
Bast from the past: the fibre architectures and properties of Ancient Egyptian and Peruvian fishing nets
No full textInternational audienceBast fibres have been critical materials in the evolution of human history. In particular, their use in fishing technology as well as in maritime transport has enabled mobility, livelihoods, and the exchange of goods and transmission of cultures in human societies. Here, we compare fishing nets from two distant but contemporaneous groups at the end of the 4th millennium BCE: one from Neolithic period in Egypt and the other from the Middle Preceramic Peruvian Pacific coast. The fishing nets possess substantially similar textile architectures even though they use bast fibres from different species: domesticated cf. Linum usitatissimum L. (flax linen) by the Ancient Egyptians and cf. Asclepias . (milkweed) by the coastal Peruvian community. We examine these two fibre types and show that despite their distinct morphological and ultrastructural characteristics, their processing and manufacture share some similarities, both 2-ply with Z final torsion. Multiphoton, atomic force, and scanning electron microscopy are supplemented by 3D micro-computed X-ray phase-contrast tomography to investigate the unique architectures of the yarns and their fibres’ artefacts. We demonstrate the use of state-of-the-art micro-spectroscopy techniques for archaeobotanical studies and use fishing nets as a new lens to unravel the episteme and techne of fibre and textile production in the past
Enhancing the Thermal Performance of Solar Air Heaters Using Heat Storage Medium: An Experimental Study With Energy, Exergy, and Economic Approach
No full textInternational audienceAbstract A solar air heater (SAH) is a simple device that collects solar radiation and transfers it to the processed air generally used in several thermal engineering applications such as space and industrial process heating and food drying, but its utilization is only during sunny hours. Among the methods of ameliorating its employing to heat air during the off-sunshine period is through the addition of heat storage medium inside the SAH for storing the sun's radiation as thermal energy. The main objective of this experimental study is to predict the effect of the heat storage medium on the thermal performance of SAH. To achieve this goal, three different configurations of SAHs were designed and constructed in the Laboratory of Electro–Mechanic Systems, namely, traditional SAH with natural circulation (T-SAH), SAH with a centrifugal air blower (F-SAH), and SAH with a centrifugal air blower and coupled with an internal heat storage medium (FS-SAH). They were tested and compared under the same ambient conditions of Sfax, central-eastern Tunisia. Experimental results showed that the T-SAH gives higher temperatures than the F-SAH and FS-SAH during the period from 8 a.m. to 3 p.m. From 3 p.m. to 7 p.m., the temperatures of FS-SAH are the highest when compared with the other two SAHs. Through this period, the thermal energy per unit time obtained by FS-SAH, F-SAH, and T-SAH is 2.15 kW, 0.23 kW, and 0.22 kW, respectively. Due to the use of salt water as a heat storage medium, the thermal energy per unit time of FS-SAH is enhanced by 1.92 kW (corresponding to 89.3%) and 1.93 kW (corresponding to 89.77%) higher than the F-SAH and T-SAH, respectively. The FS-SAH offers higher thermal and exergy efficiency as compared to the T-SAH and F-SAH during the same period. The economic evaluation showed that the money saved by FS-SAH is 96% and 89.51% higher than the T-SAH and F-SAH, respectively. Therefore, the employ of salt water as a heat storage medium is a positive attempt to enhance the thermal performance of SAHs during the off-sunshine period of this experimental testing
Dating of Quaternary deposits on the Coast of Brittany (W France) by Optically Stimulated Luminescence and Terrestrial Cosmogenic Nuclides: Preliminary results of the cronBRET Project
No full textNational audienceThe Quaternary record along the Coast of Brittany (W France) is well represented, offering important information about the geomorphological processes that have shaped this coast during this period. However, chronological data using numerical dating methods are very scarce leading to uncertain hypotheses put forward on the basis of correlations and extrapolations. Thanks to the cronBRET Project (MSCA-Bienvenüe Bretagne COFUND 2023) from the Geo-Ocean Lab of the Université de Bretagne Sud and the RenDaL laboratory of Géosciences-Rennes (Univ. Renes), in collaboration with the Cosmogenic Laboratory of the Institute of Geology and Mineralogy of the University of Cologne (Germany) and the Institute of Geology of the University of Coruña (Spain), numerous sedimentary outcrops along the Bretagne Coast are currently dated. For the burial age calculation, the optically stimulated luminescence (OSL) signal of quartz sands included in the sedimentary matrix is analyzed, as well as the concentration of 10Be and 26Al produced in situ, as a consequence of cosmic-ray interaction with quartzite cobbles, by using the isochron method. The first results include those obtained in the Falaisse de La Mine D'Or at Pénestin (SE Brittany), with a lower unit dated at 2.7 My (Plio-Quaternary boundary). The upper unit has been dated by OSL between 410 and 260 ky (Middle Pleistocene). As for the coastal deposits dated in Morbihan (ie, Betahon, Rhuys, Ploemeur), ages between 265 and 125 ky have been obtained. These data will be complemented with the dating of several sedimentary deposits from Brittany's West Coast (Finisterre) and North Coast (Côtes d´Armor) to achieve a comprehensive analysis at regional scale. This study highlights the importance of numerical dating as an essential tool to constrain the formation of coastal sediments within a more accurate paleoclimatic framework and integrate them in the glacioeustatic and neotectonic processes linked to the Glacial-Interglacial cycles of the Quaternary, and more specifically during the last 500,000 years
Évolution du travail et du management des collaborateurs en cabinet comptable : analyse des effets sur le présentéisme, le conflit travail-hors travail et le stress au travail
No full textInternational audienc
"L’avis 1/94, spectateur et acteur d’une recomposition internationale et européenne.CJCE, avis 1/94 du 15 novembre 1994, Compétence de la Communauté européenne pour conclure l’Accord instituant l’Organisation mondiale du commerce"
No full textInternational audienceLe 15 novembre 1994, la Cour de justice des Communautés européennes a rendu un avis relatif à la compétence de la Communauté européenne pour conclure l’Accord instituant l’Organisation mondiale du commerce et notamment l’Accord général sur le commerce des services (GATS) et l’Accord relatif aux droits de propriété intellectuelle qui touchent au commerce, y compris le commerce des marchandises de contrefaçon (TRIPS). Cet avis a été à l'époque abondamment commenté, essentiellement pour analyser sa contribution à la notion de politique commerciale commune et, au-delà, à la théorie des compétences externes de la Communauté. Près de trente plus tard, quel regard porter sur l’avis 1/94 ? S’agissant de son objet, force est de constater que, malgré les précisions apportées par les traités de révision successifs , les questions relatives au contenu de la politique commerciale commune ainsi qu’à l’étendue des compétences externes de l’Union européenne continuent de soulever des difficultés juridiques dans la conclusion des accords internationaux . À cet égard, l’avis 1/94 reste « une grande décision », fondatrice d’une nouvelle manière d’appréhender les compétences externes de l’Union européenne
