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The use of climate reanalysis data to understand historical storm impacts recorded in coastal environments with geomorphological methods
No full textInternational audienceIn the current context of climate change, extreme coastal events are becoming a major environmental challenge. According to the latest findings from the Intergovernmental Panel on Climate Change (IPCC), rising sea levels could ultimately displace 280 million people worldwide (Pörtner et al., 2019). With nearly 60% of the global population living within 150 km of the coast, as reported by the International Union for Conservation of Nature (IUCN), coastal flooding poses a significant and ongoing threat to nearshore societies. While the influence of climate change on tropical cyclones is well-documented, its impact on extratropical storms remains uncertain (Masson-Delmotte et al., 2021). The IPCC has observed a poleward drift in extratropical storm trajectories over recent decades in both hemispheres but highlights the difficulty of assessing the future effects of rising greenhouse gas emissions on these storms (Wang et al., 2006). Currently, only the increase in associated precipitation is widely accepted by the scientific community (Semmler et al., 2004). Although European coastal extreme events are becoming more frequent due to global mean sea-level rise, the long-term climatological dynamics of storms affecting Europe remain poorly understood. To address this gap, historical storm records are essential. For instance, new digital approaches based on a 1996–2015 dataset have been applied to predict storm characteristics and occurrences in Western France (Frifra et al., 2024).To support these new digital methods, this study aims to improve the precision of historical storm archives using reanalysis data. Geomorphological methods, such as sedimentology and dendrochronology (Pouzet et al., 2018), have been used to understand short- and long-term storm variability in western France, supplemented by detailed written archives. These environmental methods extend storm chronologies back several decades or even centuries, providing greater temporal depth for predictive models. However, the accuracy of dating decreases with the age of the archives, increasing uncertainty for older records. To address this limitation, climate reanalysis data are used to improve dating precision and identify specific weather and/or marine parameters that played key roles in generating the environmental impacts recorded in geomorphological archives (Pouzet and Idier, 2024).This study explores the potential of reanalysis data to understand how historical storms have impacted coastal physical and societal environments. Using ERA5 ocean-atmosphere data (Hersback et al., 2020) provided by the European Centre for Medium-Range Weather Forecasts (ECMWF), we present new methodologies to apprehend the evolution of historical storm activity in western Europe. These approaches are tested on major storms that impacted coastal environments during the XIXth and the XXth centuries, within the temporal scope of the ERA5 reanalysis data. The storm tracks of historical events that caused geomorphological marks detected in the environment are estimated based on their wind gust records. A spatial analysis model, utilizing GIS techniques, is employed to understand the overall extent of the most intense winds per storm. This model helps identify potential physical and societal impacts of historical storms and refines historical spatial storm parameters, including their precise “impact trajectories”. Additionally, we present new methods to detect the specific ocean-atmospheric parameters that induced geomorphological imprints on coastal environments and impacted nearshore societies. Our findings indicate that wave height is one of the main oceanographic parameters explaining marine impacts along the coastline, while maximum wind gusts play a key role in storm impacts inland.This study demonstrates that climatic reanalysis data are essential for understanding historical storm dynamics recorded during the reanalysis timespan, reducing dating uncertainties, and confirming the hazardousness of these storms in relation to current coastal issues. Combining reanalysis data with geomorphological archives is crucial, as environmental dating remains subject to significant error margins. In future research, extending climatic reanalysis datasets to earlier periods could provide critical insights for interpreting geomorphological data, as sedimentological and dendrochronological archives now offer storm records spanning millennia. By obtaining more accurate and ancient historical data through these methods, future models will be able to make precise predictions in the context of ongoing climate change. Given the high uncertainty surrounding extratropical storm dynamics, this research addresses a major contemporary issue
ICMJE Should Create a Certification System to Identify Predatory Journals
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Key role of extracellular vesicles in the induction of necroptosis and apoptosis by a mixture of polycyclic aromatic hydrocarbons in the context of a steatohepatitis-like state
No full textInternational audienceA positive association between human exposure to environmental pollutants and progression from benign hepatic steatosis to advanced chronic liver diseases has been documented. Among chemicals found in air pollution, polycyclic aromatic hydrocarbons (PAHs) are of particular concern, due to their omnipresence in the environment. Ingestion of contaminated food is the primary route of exposure. Previous studies on the ability of PAHs to induce the pathological progression of liver steatosis have been limited to the analysis of individual PAHs. The aim of this study was therefore to examine the effects of a mixture of PAHs whose composition closely recapitulates that of contaminated food. The PAH mixture elicited both a steatohepatitis-like state in steatotic WIF-B9 hepatocytes (100 nM for 72 hours) and the progression of steatohepatitis in rats fed a lipid-enriched diet (0.8 mg/kg for 90 days). The PAH mixture induced transient necroptosis at 5 hours followed by a gradual increase in cellular apoptosis. PAH metabolism-dependent necroptosis appeared to be responsible for the development of the secondary apoptosis. Hepatocyte exposure induced a necroptosis-dependent release of extracellular vesicles (EVs), that appeared to be protective against necroptosis; however, those necroptotic EVs triggered apoptosis in recipient hepatocytes. Blocking of ASGR EV receptors with asialofetuin inhibited the interaction of EVs with hepatocytes and hence apoptosis. In conclusion, EV release seems to be crucial to avoid necroptosis, but inhibition of EV uptake can protect against apoptosis
Offering a second-hand gift: An exploration of consumers’ profiles in the toys sector
No full textInternational audienceBuying second-hand products is now a significant societal trend established in the games and toys sector. With the growing awareness of environmental issues and the impact of inflation on families' purchasing power, second-hand toys are no longer purchased solely "for oneself" or exclusively within one's household. Today, second-hand toys are being "offered" as gifts. This research is based on a qualitative study conducted with 20 parents. Beyond the "resistors" who remain the majority among individuals who have experienced or anticipate this practice, the study identifies a typology with four profiles: "concealers”, "finders", "selectives", and "valuers". Managerial recommendations are provided to enable stakeholders to embrace this trend and support consumers in adopting this emerging practice
Peculiar Rainbows in Saturn's E Ring: Uncovering Luminous Bands Near Enceladus
No full textInternational audienceWe report observations of stripe-like features in Enceladus' plumes captured simultaneously by Cassini's VIMS-IR and ISS NAC instruments during flyby E17, with similar patterns seen in VIMS-IR data from flyby E13 and E19. These parallel stripes, inclined at approximately 16° to the ecliptic and 43° to Saturn's ring plane, appear continuous across images when projected in the J2000 frame. A bright stripe, most visible at wavelengths around 5 μm, acts as the zeroth-order diffraction peak of a reflection grating with an estimated groove spacing of 0.12-2.60 mm, while adjacent stripes are attributed to higher-order diffraction peaks. We suggest that this light-dispersing phenomenon originates from an inclined periodic structure within Saturn's E ring. This structure, constrained between Saturn's G-ring and Rhea's orbit, likely consists of fresh ice particles supplied by Enceladus' plumes
Étudier la part créative du supportérisme ultra. Proposition à partir du cas de Marseille dans les années 1980 et 1990
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Innovative Trajectory Analysis Reveals Dynamics and Risk Factors of Post‐Kidney Transplant Diabetes Mellitus in a French Cohort
No full textInternational audienceBackground and Hypothesis Post‐transplant diabetes mellitus (PTDM) is a common, dynamic complication after kidney transplantation (KT) that may resolve over time. To better understand and prevent PTDM, we analyzed its prevalence, evolution, and influencing factors. Methods Data from the French national ASTRE database at different post‐transplantation periods (P) were analyzed. PTDM was defined by fasting blood glucose (FBG) ≥1.26 g/L, HbA1c ≥ 6.5%, or the use of hypoglycemic medications in kidney transplant recipients without diabetes. Patient trajectories were identified using group‐based trajectory models (GBTM), and associated factors were examined. Results Among 2898 patients, PTDM prevalence was 27.3% at P1 (>M2, ≤M6), 21.3% at P2 (>M6, ≤M18), 19.8% at P3 (>M18, ≤M30), and 19.9% at P4 (>M30, ≤M42). Analysis of 1825 patients identified four trajectories: no PTDM (67%), late‐onset PTDM (6%), remission after P1 (10%), and early, persistent PTDM (17%). Late‐onset PTDM was linked to history of cardiovascular disease, higher BMI at transplantation, HCV positive status, and weight gain. Early, persistent PTDM was associated with older age, higher BMI, HVC positive status, history of cardiovascular disease, and tacrolimus use. PTDM remission was linked to lower BMI. Corticosteroids contributed to both late‐onset and persistent PTDM, while switching between tacrolimus and cyclosporine did not significantly affect progression. Conclusion This study confirmed the high prevalence and dynamic nature of PTDM after transplantation, emphasizing the critical role of pretransplant cardiovascular disease, BMI, and early post‐transplant weight gain in the onset or remission of PTDM
Use of mortality tables by level of deprivation in the study of social inequalities in cancer survival
No full textInternational audienceBackground: Previous studies have reported lower net survival probabilities for socioeconomically deprived patients, using non-deprivation specific lifetables. Not accounting for the social gradient in background mortality could potentially overestimate the effect of deprivation on net survival. The aim of this study was to estimate the impact of taking into account the social gradient of expected mortality in the general population on the study of the social gradient of survival of people with cancer.Methods: French cancer registry data was analyzed, with 190,902 incident cases of nineteen cancer sites between 2013 and 2015. Deprivation was measured using the European deprivation index (EDI). Net survival was estimated thanks to additive models with French lifetables stratified on deprivation level with the EDI, using the non-parametric Pohar-perme method and flexible excess hazard modelling with multidimensional penalized splines, firstly with non-specific lifetables then with the deprivation specific-lifetables.Results: A significant effect of EDI on excess mortality hazard (EMH) remained when using the deprivation-specific lifetables for colorectal, lung cancer and melanoma in both sexes, and esophagus, bladder, head and neck and liver cancer for men, and breast, cervix and uterine cancer for women. The only site where the effect of EDI on EMH was no longer significant when using deprivation-specific lifetables was prostate cancer.Conclusions: The use of deprivation-specific lifetables confirms the existence of a social gradient in cancer survival, indicating that these inequalities do not result from inequalities in background mortality. Development of such deprivation-specific lifetables for future years is crucial to understand mechanisms of social inequalities and work towards reducing the social burden
Bocage et champs fleuris : les messicoles et leur symbolique
No full textEn ligne sur la chaîne YouTube de Radio Ondine sous le titre « Le secret des plantes messicoles »Emission de Radio Ondine dans le cadre de la seconde édition du festival Secrets de Nature à MédréacAs part of the second edition of the 'Secrets de Nature' festival in Médréac (Ille-et-Vilaine, France), Radio Ondine organized three round-table discussions. This one focused on messicolous plants. Margot Lyautey provided a historian's perspective on the relationship between biodiversity in the fields and the agricultural policies of the modernist turn in the mid-twentieth century. Emilie Stoll recalled the anthropological and political dimension of these flowers (poppy, cornflower and daisy as the three colors of the national flag), particularly in the French memory of the Great War. Yvon Le Caro proposed a geographical reading of messicolous plants as an example of commensal nature between wild and domestic, an argument for agro-ecology (land sharing rather than land sparing). Four chronicles enrich the program: Floriane Haquin presents the biographical background of Margot Lyautey; Jean-Philippe Dartois talks about his relationship with messicole plants as a local child; a CM2 pupil brilliantly places herself from the point of view of a field nigella; Martine Leruste offers a tempting book review.Dans le cadre de la seconde édition du festival ‘Secrets de Nature’ à Médréac (Ille-et-Vilaine, Radio Ondine a organisé trois tables rondes (ou plateaux radio). Celle-ci porte sur les messicoles. Margot Lyautey a apporté le point de vue de l’historienne sur les rapports entre la biodiversité des champs et les politiques agricoles du tournant moderniste du milieu du XXe siècle. Emilie Stoll a rappelé la dimension anthropologique et politique de ces fleurs (coquelicot, bleuet et marguerite comme les trois couleur du drapeau national) en particulier dans la mémoire française de la Grande Guerre. Yvon Le Caro a proposé une lecture géographique des messicoles comme exemple de nature commensale entre sauvage et domestique, argument pour l’agro-écologie (le land sharing plutôt que le land sparing). Quatre chroniques enrichissent l’emission : Floriane Haquin présente le parcours de Margot Lyautey ; Jean-Philippe Dartois témoigne de son rapport aux messicoles en tant qu’enfant du pays ; une élève de CM2 se place brillamment du point de vue d’une nigelle des champs ; Martine Leruste propose une alléchante revue de livres
La « médecine mitochondriale » à l’aune du quatrième plan national maladies rares (PNMR4)
No full textInternational audienceThe aim of the MITOMICS project is to establish a clinical database of patients diagnosed with mitochondrial diseases, combined with a « multiomics » integrated approach in order to gain a better understanding of the molecular mechanisms underlying these diseases, and ultimately, to offer better patient care. The MITOMICS project thus contributes to the consolidation of a French “mitochondrial medicine”, a notion that deserves to be examined. With the upcoming launch of the fourth national plan for rare diseases, it is an example of the study and management of rare and ultrarare diseases in France. This article traces the emergence of mitochondrial medicine since the early 1960s. It presents its main characteristics (genocentrism, strong techno-dependence), as well as its major technical and theoretical limitations, with a view to developing personalized mitochondrial medicine for the years to come.Le projet MITOMICS vise à développer une base de données cliniques et « multi-omiques » provenant de patients atteints de maladies mitochondriales, à l’échelle nationale, afin de mieux comprendre les mécanismes moléculaires responsables de ces maladies, et de proposer, à terme, une meilleure prise en charge. Il participe ainsi à la consolidation d’une « médecine mitochondriale » française qui, à la veille du lancement du quatrième Plan National Maladies Rares (PNMR4), est emblématique de l’étude et de la prise en charge de ces maladies, et mérite donc d’être examinée. L’article retrace l’histoire de l’émergence de cette médecine. Il en expose les principales caractéristiques (génocentrisme, techno-dépendance) ainsi que les limites, dans la perspective d’une « médecine mitochondriale » personnalisée