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Culture-Driven Plasticity and Imprints of Body-Movement Pace on Musical Rhythm Processing
No full textInternational audienceMusic naturally induces human movement through its rhythmic structure. Conversely, synchronised body movement can shape rhythm perception – a short-term effect that is likely influenced itself by lifelong cultural exposure. Yet, direct experimental evidence for both short- and long-term modulation of rhythm processing through movement remains limited.To address this, we present a registered report using electroencephalography (EEG) and hand-clapping responses to a highly syncopated, metrically ambiguous rhythm derived from West/Central African musical traditions (N = 80). These neural and behavioural responses were recorded separately in participants from West/Central Africa and Western Europe (N = 60) before and after a body-movement session involving stepping and clapping to a cued beat (either three- or four-beats meter, the latter concurring with original music-cultural conventions).African participants exhibited a significant short-term effect, clapping more consistently and in closer alignment with the beat as cued in the body-movement session. They also more reliably interpreted the rhythm in line with cultural conventions, both before and after movement. In contrast, European participants showed no significant short-term movement effect. A sibling study was then conducted on an additional Western cohort (N = 80), where the body movement session was replaced by watching while staying still audiovisual clips of individuals performing the same body movement as in the first study. In contrast with Study 1, behavioural responses to the cued beat were found to be significantly more consistent after the training session, suggesting that multisensory inputs, possibly activating motor representation without actual movement production, can elicit a short-term effect even when production of actual movement does not.Finally, inconsistencies between neural and behavioural data in both studies suggest that a brief training session alone may not robustly stabilise a beat interpretation that can be automatically reactivated in neural activity after the movement cessation, particularly in response to a complex, syncopated rhythm. Nonetheless, when participants are compelled to move to such a rhythm, they can draw on learnt beat–rhythm association to guide movement timing
Les enjeux du changement climatique pour les activités récréatives, ludiques et sportives en zone littorale
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The intersection of technological trajectories : The case of medical instrumentation and artificial intelligence
No full textInternational audienceThis article examines the interaction between the technological trajectories of artificial intelligence (AI) and medical instrumentation (MI) from 2010 to 2020. Using patent data, we created a cumulative graph of technological codes and measured the direction and intensity of the two fields’ interactions. The results reveal three things. First, there was a rapid expansion of AI/MI interaction, with a tendency toward a center/periphery structure in which AI technologies are dominant. Second, cognitive flows are highly asymmetrical, with AI transferring many more new combinations to MI than vice versa. Third, our prediction method had a very high success rate at the beginning of the decade; however, its advantage eroded as the structure solidified, reflecting the transition from a logic of exploration to a logic of exploitation
Regard croisé entre villes portuaires méditerranéennes. Quelle évolution et emprise spatiale de la croisière ?
No full textInternational audienceLa mer Méditerranée, avec plus de 4,4 millions de passagers soit une augmentation de 19% depuis 2019 (avant la crise COVID), est le second pôle mondial pour la croisière après les Caraïbes (CLIA, 2022). Ce secteur d’activité a connu une croissance rapide à partir de la fin des années 1960 et cela malgré les événements divers qui ont mis en crise ce secteur ces dernières années (naufrage du Costa Concordia en 2012, pandémie Covid-19 en 2020 et 2021). Ce développement rapide repose sur des facteurs classiques comme la présence d’infrastructures dédiées à l’accueil de ces flux au cœur de villes et donc en proximité des sites culturels et historiques ou encore un climat chaud. Les ports majeurs, souvent connectés à des villes touristiquement attractives, se sont imposés comme des hubs importants pour le marché de la croisière dépassant le million de passagers annuel (Barcelone, Marseille, Venise ou encore Le Pirée). Toutefois aujourd’hui la situation est assez contrastée et en cours de transition. Au sein de nombreuses places portuaires touristiques telles que Venise, Marseille ou Barcelone, le secteur de la croisière fut dénoncé par la société civile et le monde associatif pour son impact sociétal (nombreux touristes dans les villes) mais surtout environnemental et sanitaire. Face à ces contestations, les municipalités ont réagi souvent en limitant le nombre d’escales en instantanée par jour ou encore en développement des aménagements, parfois palliatifs, tel que le branchement des navires à quai. Cependant, la diminution du nombre d’escales peut être compensée par l’accroissement de la taille des paquebots et par un report des escales dans des ports secondaires. Le marché de la croisière en Méditerranée semble ainsi se diffuser vers de nouveaux ports plus petits comme Sète en France, Monopoli en Italie ou encore Tarragone en Espagne.L’objectif de ce chapitre est donc d’étudier l’évolution et la diffusion du marché de la croisière en mer Méditerranée. Pour cela, nous dresserons un diagnostic de l’évolution de la croisière dans les dix dernières années et nous établirons des liens entre petits ports et grandes villes touristiques afin de déterminer les phénomènes d’externalisation du marché de la croisière. Nous étudierons ces évolutions au regard des typologie des escales (taille des navires, fréquence dans l’année, etc.), des investissements en cours ou à venir (projets de nouveaux terminaux, etc.) et également en intégrant une dimension sur les stratégies spatiales des compagnies maritimes (ancrages territoriaux, liens avec le système de gouvernance des petits ports, logiques commerciales, etc.)
Analyse 3D de la forme des otolithes pour l'identification des stocks
No full textInternational audienceOtoliths, calcified structures located in the inner ear of fish are widely used for age determination and species identification. Beyond these functions, otolith morphology also encodes valuable information about environmental conditions, genetic background, life history traits, and ontogeny. Since otolith shape is influenced by these combined effects, understanding these sources of variation is essential for accurate biological interpretation.However, most existing studies rely on two-dimensional (2D) images, which represent only a single projection of the otolith’s inherently three-dimensional (3D) structure. This research advances beyond traditional 2D methods by employing 3D otolith imaging to more comprehensively capture external morphological features. The workflow incorporates standardized image acquisition ensuring consistent scale, position, and orientation followed by feature extraction using Fourier descriptors and principal component analysis (PCA). Both unsupervised and supervised machine learning techniques, including clustering and classification algorithms, are applied to categorize fish specimens.The 3D analysis demonstrates suitable performance in species identification and classification based on life-history traits and ontogenic variations. It also reveals potential for distinguishing biological and ecological factors such as sex, maturity stage, and otolith laterality (left/right). A multivariate mixed-effects model found no significant asymmetry between left and right otoliths in 2D analyses but detected clear geographical differentiation. In contrast, 3D shape analysis revealed significant effects of both otolith side and geographic origin. Furthermore, hierarchical clustering and Random Forest models based on 3D data outperformed their 2D counterparts in fish stock discrimination.While some classification challenges remain due to overlapping genetic, ontogenic, and environmental influences, the study concludes that 3D otolith shape analysis represents a major advancement in fisheries science. It provides richer and more precise morphological information, improving the accuracy of species classification, stock identification, and the understanding of life-history diversity
Temperature dependent kinetics and insights on the gas-phase products of the reaction between prenol and hydroxyl radicals
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Comparison of submerged and air liquid interface exposure : limitations and differences in the toxicological effects evaluated in bronchial epithelial cells
No full textInternational audienceAirborne particulate matter (PM) is the primary environmental cause of death worldwide. The understanding ofthe toxicological mechanism has improved over the last decades, nonetheless now novel exposure systems allowthe possibility to mimic the in vivo interaction between particles or particle constituents and lung cells. Here wereport the results obtained after exposure to the organic extract of fine PM (PM2.5-0.3) of the BEAS-2B cellscultured in submerged or at the air liquid interface (ALI) conditions. Deposition efficiency of both PM and itsorganic extract was followed. Cell viability, inflammatory responses and gene expression were then evaluated.The comparison of submerged vs ALI exposure revealed significant differences in the expression of specific genessuch as CYP1A1 and NQO1 6h after exposure and CYP1B1 and NFkB1 24h post exposure. Also, the resultsdemonstrate the importance of evaluating the efficiency of deposition of the treatment to avoid misinterpretationof the results. PM particles determined an extremely low deposition efficiency, making it impossible to use thisparticle for ALI exposure tests. Although biological results, such as gene expression, may vary between the twoexposure approaches (submerged or ALI), the ALI exposure should be preferred as it is more representative ofhuman exposure via the respiratory route
CO2 methanation catalysts derived from Ni-alkaline earth metal carbonates
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Terahertz Frequency Comb High-Resolution Heterodyne Spectrometer
No full textInternational audienceWe demonstrate the advantages of THz frequency combs for high-resolution spectroscopy. This benefits from wide spectral coverage and the exact knowledge of the frequency position of each comb component. Heterodyne detection combined with a fast Fourier spectrometer enables rapid and simultaneous measurement of more than 80 frequency comb modes covering a 7.5 GHz bandwidth. A spectrum is obtained in under 20 minutes yielding a uniform resolution of 70 kHz. This new setup has been validated by recording more than 150 lines of methanol around 723 GHz, and represents a new solution to exploit THz frequency combs for high-resolution spectroscopy
Reliability and Accuracy of the Fitbit Charge 4 Photoplethysmography Heart Rate Sensor in Ecological Conditions : Validation Study
No full textInternational audienceBackground :Wrist-worn photoplethysmography (PPG) sensors allow for continuous heart rate (HR) measurement without the inconveniences of wearing a chest belt. Although green light PPG technology reduces HR measurement motion artifacts, only a limited number of studies have investigated the reliability and accuracy of wearables in non–laboratory-controlled conditions with actual specific and various physical activity movements. Objective : The purpose of this study was to (1) assess the reliability and accuracy of the PPG-based HR sensor of the Fitbit Charge 4 (FC4) in ecological conditions and (2) quantify the potential variability caused by the nature of activities. Methods :We collected HR data from participants who performed badminton, tennis, orienteering running, running, cycling, and soccer while simultaneously wearing the FC4 and the Polar H10 chest belt (criterion sensor). Skin tone was assessed with the Fitzpatrick Skin Scale. Once data from the FC4 and criterion data were synchronized, accuracy and reliability analyses were performed, using intraclass correlation coefficients (ICCs), Lin concordance correlation coefficients (CCCs), mean absolute percentage errors (MAPEs), and Bland-Altman tests. A linear univariate model was also used to evaluate the effect of skin tone on bias. All analyses were stratified by activity and pooled activity types (racket sports and running sports). Results :A total of 77.5 hours of HR recordings from 26 participants (age: mean 21.1, SD 5.8 years) were analyzed. The highest reliability was found for running sports, with ICCs and CCCs of 0.90 and 0.99 for running and 0.80 and 0.93 for orienteering running, respectively, whereas the ICCs and CCCs were 0.37 and 0.78, 0.42 and 0.88, 0.65 and 0.97, and 0.49 and 0.81 for badminton, tennis, cycling, and soccer, respectively. We found the highest accuracy for running (bias: 0.1 beats per minute [bpm]; MAPE 1.2%, SD 4.6%) and the lowest for badminton (bias: −16.5 bpm; MAPE 16.2%, SD 14.4%) and soccer (bias: −16.5 bpm; MAPE 17.5%, SD 20.8%). Limit of agreement (LOA) width and artifact rate followed the same trend. No effect of skin tone was observed on bias.Conclusions :LOA width, bias, and MAPE results found for racket sports and soccer suggest a high sensitivity to motion artifacts for activities that involve “sharp” and random arm movements. In this study, we did not measure arm motion, which limits our results. However, whereas individuals might benefit from using the FC4 for casual training in aerobic sports, we cannot recommend the use of the FC4 for specific purposes requiring high reliability and accuracy, such as research purposes