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Missed Opportunity for Fibrinolysis in ST-Segment–Elevation Myocardial Infarction: The Nationwide France-PCI Registry
No full textInternational audienceBackground Timely reperfusion is a key quality-of-care target in ST-segment–elevation myocardial infarction (STEMI). When primary percutaneous coronary intervention (PPCI) cannot be delivered within 120 minutes from first medical contact (FMC), guidelines recommend fibrinolysis as early as possible within 12 hours of symptom onset in eligible patients. We quantified missed opportunities for fibrinolysis in a nationwide STEMI network. Methods We analysed consecutive STEMI patients enrolled ≤24 hours from symptom onset in the France-PCI registry (2014–2022). FMC was approximated by the first diagnostic ECG. Initial reperfusion was classified as timely PPCI (FMC-to-device ≤120 min), delayed PPCI (>120 min), or fibrinolysis. Among delayed PPCI, eligibility for fibrinolysis required no oral anticoagulant, no prior stroke, and no documented contraindication. We evaluated temporal trends, regional variation, and outcomes. Results Among 19,472 patients, 12,633 (64.9%) underwent timely PPCI, 5,895 (30.3%) delayed PPCI, and 944 (4.8%) fibrinolysis. Timely PPCI increased over time, whereas fibrinolysis declined. Among delayed PPCI, 3,279/5,895 (55.6%) presented within the prespecified early-presenter window (symptom-to-ECG ≤3 h) and met our strict fibrinolysis-eligibility criteria, yet underwent delayed PPCI; this proportion remained stable across years, with marked regional heterogeneity. Fibrinolysis use was favoured by mobile intensive care units, helicopter transport, and longer distance to PPCI centres, whereas older age was associated with delayed PPCI without fibrinolysis. Conclusions In this national STEMI network, more than half of delayed PPCI in eligible early presenters represented a persistent missed-fibrinolysis gap. Routine audit of delayed PCI and missed fibrinolysis as system-level quality metrics should guide time-based pre-hospital triage and align reperfusion with guideline-recommended targets
Variability and trend analysis of temperature and height in the upper troposphere and stratosphere region over the tropics (Réunion), by combining balloon-sonde and satellite measurements
No full textInternational audienceTropopause height and temperature play a crucial role in atmospheric chemistry and radiative forcing and serve as key indicators of anthropogenic climate change. However, accurately determining this parameter requires advanced remote sensing techniques. This study compares tropopause height and temperature estimated from in-situ and remote sensing instruments (SHADOZ and COSMIC-1) with reanalysis data from MERRA-2 over Réunion from 2006 to 2020. The results reveal strong agreement between vertical temperature profiles obtained from SHADOZ and COSMIC-1, demonstrating that both can reliably estimate tropopause height using the Cold Point Temperature (CPT) and/or Lapse Rate Temperature (LRT) methods. Conversely, while MERRA-2 assimilates data from these sources, its fixed vertical resolution limits its ability to capture tropopause height variations accurately. Given the consistency between SHADOZ and COSMIC-1, their data were combined to construct a more refined dataset, which was then used to assess temperature trends. The analysis indicates a high influence of annual and semi-annual oscillations in Tropopause height dynamics, as well as, a decreasing trend in CPT and a slight increase in the Lapse Rate Tropopause (LRT) height
Global stability in an age-structured SIRS malaria transmission model
No full textThis paper proposes and analyzes a malaria transmission model structured by the chronological age of the human host population. The model couples an age-structured SIRS system for humans, incorporating waning immunity, with an SI system for mosquitoes under mass-action transmissions. Using integrated semigroup theory and spectral analysis, we establish the well-posedness of the model, derive the basic reproduction number, and prove the global asymptotic stability of the parasite-free equilibrium by using a Lyapunov functional, when , thereby excluding the possibility of backward bifurcation. Numerical simulations further suggest the global stability of the endemic equilibrium when R_0>1
Faisabilité d’une méthode de marquage-recapture par apparentement proche pour l’évaluation des stocks d’espadon de l’océan Indien (Xiphias gladius).
No full textInternational audienceThe Indian Ocean Tuna Commission (IOTC) manages swordfish, Xiphias gladius, a species of high economic importance in the Indian Ocean. Current stock assessments rely on catch per unit effort indices, which can be biased, complicating reliable abundance estimates. We explored alternative approaches by assessing the feasibility of the close-kin mark– recapture (CKMR) method, a powerful genetic-based approach. This pilot study aimed to validate protocols and guide future CKMR implementation at the IOTC scale. CKMR simulations were conducted to estimate the sample sizes required to detect sufficient kin pairs. Kinship analyses assumed a single panmictic population across the Indian Ocean, consistent with current IOTC management. A total of 2068 individuals were genotyped using SNP markers, identifying one parent-offspring pair (POP) and at least two half-sibling pairs (HSPs). As predicted by simulations, this sampling scale precludes robust estimation. However, results indicate that robust CKMR-based estimates could be achieved by sampling at least 18,000 swordfish over three years, representing about 20% of the current sampling effort already undertaken by contracting parties. The annual cost of genomic data generation for CKMR represents less than 0.5% of the first-sale market of swordfish in the Indian Ocean. Overall, this study supports the feasibility of CKMR for swordfish and provides a foundation for scaling up future programs to improve Indian Ocean stock assessments
3D Imaging Contribution in Pediatric Surgical Oncology: A Multistakeholder Assessment Study
No full textInternational audienceIntroduction: Medical imaging is crucial for surgical planning, yet surgeons struggle with mental transformation of 2D images into 3D representations, particularly in complex pediatric pelvic anatomy. This study evaluated perceived benefits of 3D imaging with tractography compared to conventional 2D MRI in pediatric pelvic tumor surgery.Methods: A nationwide study assessed three groups: non-medical personnel (n=30), medical trainees (residents and fellows; primary analysis n=61, excluding 3 medical students), and senior pediatric surgeons (n=12). Using 3-Tesla MRI with specialized protocols including highresolution CoroT2cube and diffusion tensor imaging, participants evaluated five clinical cases in both 2D and 3D formats using 7-point Likert scales. Statistical analysis employed Wilcoxon paired tests with Bonferroni correction.Results: All groups showed significant improvements in perceived understanding with 3D imaging. Non-medical personnel scores increased from 4.24 (±0.69) to 6.27 (±0.28) (p<0.001), particularly in understanding disease and surgical objectives. Medical trainees improved from 5.08 (±0.61) to 6.42 (±0.49) (p<0.001), with enhanced understanding of surgical objectives and anatomical relationships. Senior surgeons' scores increased from 5.02 (±0.69) to 6.33 (±0.52) (p<0.001), showing significant improvements in preoperative planning and family communication. Effect sizes were substantial across groups (Cohen's d: 2.80, 1.90, and 1.52 respectively), though the within-subject design likely contributes to effect size inflation.Discussion: This study provides preliminary evidence for perceived 3D imaging value in pediatric pelvic tumor surgery. Improved anatomical comprehension among non-medical personnel may benefit informed consent, while enhanced visualization aids surgical education and planning. High surgeon acceptance (92%) suggests strong acceptability, though these exploratory findings require validation before implementation recommendations can be made.Prospective studies evaluating objective clinical outcomes, workflow integration and costeffectiveness require further study.</p
Growth of the seaweed Eucheuma denticulatum (N.L. Burman) Collins & Hervey in response to local seasonal and abiotic factors variations in Madagascar in the context of climate change
No full textInternational audienceEucheuma denticulatum is a key resource in Madagascar for its iota-carrageenan production and it provides income to coastal communities. This study investigates the ecological and biochemical dynamics of E. denticulatum along the east coast of Madagascar in relation to seasonal variations and abiotic factors. Conducted between 2021 and 2022 on Sainte Marie Island, the research integrates environmental, physiological, and biochemical analyses to optimize cultivation practices. Results demonstrate that abiotic drivers (temperature, salinity, solar radiation, and nutrient availability) exert an influence on growth performance, biochemical composition, and reproductive cycles. The year 2022, characterized by warmer and more stable climatic conditions, recorded higher growth rates (+10% biomass) compared with 2021. Seasonal trends were also observed in biochemical composition: total sugars, particularly galactose, sulfate groups, and 3,6-anhydrogalactose, were identified as key indicators of carrageenan quality, with optimal values recorded during warmer months. Reproductive monitoring revealed a dominance of spermatangial thalli in October-November and the absence of cystocarps, suggesting a predominance of sporophytic reproduction under cultivation. Multivariate analyses further identified solar radiation and temperature as the main factors stimulating growth. These findings highlight the critical importance of aligning farming practices with seasonal cycles to maximize biomass yield and carrageenan quality. Beyond its industrial value, the sustainable development of E. denticulatum farming could also contribute to strengthening local food security in Madagascar in response to ongoing nutritional challenges
COMPRENDRE LA RECRUDESCENCE DES COUPS D’ETAT MILITAIRES EN AFRIQUE SUBSAHARIENNE
No full textThis article examines the resurgence of military coups in Africa as a political phenomenon embedded in contexts of institutional fragility, legitimacy crises of civilian regimes, and blocked democratic mechanisms. Drawing on both strategic interactionism and constructivist approaches, the study shows that military interventions result from calculated actions by actors operating in constrained environments, as well as from discursive efforts to legitimize power through narratives of national renewal. The analysis of transitional trajectories highlights a recurring tension between promises of rupture and dynamics of continuity, where military authorities gradually institutionalize themselves and reproduce some of the practices they initially opposed. Coups d’état thus appear less as stabilizing alternative mechanisms and more as indicators of structural dysfunctions in political orders, revealing the limitations of formal democratization processes and the need to strengthen civilian governance frameworks sustainably.Cet article analyse la résurgence des coups d'État militaires en Afrique comme un phénomène politique inscrit dans des contextes de fragilisation institutionnelle, de crise de légitimité des régimes civils et de blocage des mécanismes de régulation démocratique. En mobilisant conjointement l'interactionnisme stratégique et l'approche constructiviste, l'étude montre que les ruptures militaires résultent à la fois de calculs d'acteurs évoluant dans des environnements contraints et d'un travail de légitimation discursive fondé sur la rhétorique de la refondation nationale. L'examen des trajectoires de transition met en évidence une tension récurrente entre promesse de rupture et dynamiques de continuité, où les pouvoirs militaires tendent progressivement à s'institutionnaliser et à reproduire certaines pratiques qu'ils dénonçaient initialement. Les coups d'État apparaissent ainsi moins comme des mécanismes alternatifs stabilisateurs que comme des indicateurs de dysfonctionnements structurels des ordres politiques, révélant les limites des processus de démocratisation formelle et la nécessité de renforcer durablement les cadres de gouvernance civile
Étude nationale sur la prévalence des athlètes à risque et répercussions du syndrome de déficit énergétique relatif dans le sport (REDs) chez les traileurs et traileuses français(es) (REDs-TRAIL-Quest)
No full textIntroduction: Trail running is a demanding endurance sport characterized by high energy expenditure and sometimes inadequate nutritional practices. These factors expose athletes to low energy availability (LEA) and relative energy deficiency in sport (REDs). The main objective of this study was to assess the prevalence of REDs risk among French male and female trail runners, as well as its consequences and associated risk factors according to sex. Methods: A national cross-sectional observational study was conducted using an anonymous online questionnaire distributed between July and September 2025. REDs risk was assessed using the LEAF-Q for women and the LEAM-Q for men. Eating disorders and exercise dependence were screened using the EDE-QS and the EDS-R. Prevalence estimates were calculated with 95% confidence intervals, and sex comparisons were performed using appropriate statistical tests. Results: A total of 1,340 participants were included (956 women, 384 men; mean age 36.7 years). REDs risk was identified in 50.4% of women and 18.8% of men. The prevalence of eating disorders was higher in women (19.8% vs. 7.3%), whereas exercise dependence was similar between sexes (5.6%). Carbohydrate intake below recommendations was frequent (33.4% for efforts of 1–2.5 hours and 45.9% for longer durations). Stress fractures were reported by 12.5% of participants. Conclusion: Trail running carries a high risk of REDs, particularly in women. Early screening and nutritional education appear essential to prevent complications related to low energy availability.Introduction : Le trail running est une discipline d’endurance exigeante, caractérisée par une forte dépense énergétique et des pratiques nutritionnelles parfois inadaptées. Ces éléments exposent les athlètes à une faible disponibilité énergétique (LEA) et au syndrome de déficit énergétique relatif dans le sport (REDs). L’objectif principal de cette étude était d’évaluer la prévalence du risque de REDs chez les traileurs et traileuses français(es), ainsi que ses répercussions et les facteurs de risque associés selon le sexe.Méthodes : Une étude observationnelle transversale nationale a été menée à l’aide d’un questionnaire en ligne anonyme diffusé entre juillet et septembre 2025. Le risque de REDs a été évalué par le LEAF-Q chez les femmes et le LEAM-Q chez les hommes. Les troubles des conduites alimentaire et la dépendance à l’exercice ont été dépistés à l’aide de l’EDE-QS et de l’EDS-R. Les prévalences ont été estimées avec un IC à 95 %, et les comparaisons entre sexes ont reposés des tests statistiques adaptés.Résultats : Au total, 1 340 participants ont été inclus (956 femmes, 384 hommes ; âge moyen 36,7 ans). Un risque de REDs était identifié chez 50,4 % des femmes et 18,8 % des hommes. La prévalence des TCA était plus élevée chez les femmes (19,8 % vs 7,3 %), tandis que celle de la dépendance à l’exercice était comparable entre les sexes (5,6 %). Des apports glucidiques inférieurs aux recommandations étaient fréquents (33,4 % pour des efforts de 1 à 2,5 h et 45,9 % au-delà). Une fracture de fatigue était rapportée par 12,5 % des participants.Conclusion : Le trail running expose à un risque élevé de REDs, particulièrement chez les femmes. Le dépistage précoce et l’éducation nutritionnelle apparaissent essentiels pour prévenir les complications liées à une faible disponibilité énergétique
Growth of the seaweed Eucheuma denticulatum (N.L. Burman) Collins & Hervey in response to local seasonal and abiotic factors variations in Madagascar in the context of climate change
No full textInternational audienceEucheuma denticulatum is a key resource in Madagascar for its iota-carrageenan production and it provides in-come to coastal communities. This study investigates the ecological and biochemical dynamics of E. denticulatumalong the east coast of Madagascar in relation to seasonal variations and abiotic factors. Conducted between2021 and 2022 on Sainte Marie Island, the research integrates environmental, physiological, and biochemicalanalyses to optimize cultivation practices. Results demonstrate that abiotic drivers (temperature, salinity, solarradiation, and nutrient availability) exert an influence on growth performance, biochemical composition, andreproductive cycles. The year 2022, characterized by warmer and more stable climatic conditions, recordedhigher growth rates (+10% biomass) compared with 2021. Seasonal trends were also observed in biochemicalcomposition: total sugars, particularly galactose, sulfate groups, and 3,6-anhydrogalactose, were identified as keyindicators of carrageenan quality, with optimal values recorded during warmer months. Reproductive moni-toring revealed a dominance of spermatangial thalli in October-November and the absence of cystocarps, sug-gesting a predominance of sporophytic reproduction under cultivation. Multivariate analyses further identifiedsolar radiation and temperature as the main factors stimulating growth. These findings highlight the criticalimportance of aligning farming practices with seasonal cycles to maximize biomass yield and carrageenanquality. Beyond its industrial value, the sustainable development of E. denticulatum farming could also contributeto strengthening local food security in Madagascar in response to ongoing nutritional challenges