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European consensus-based interdisciplinary guideline for melanoma. Part 1: Diagnostics - Update 2024
No full textInternational audienceThis guideline was developed in close collaboration with multidisciplinary experts from the European Association of Dermato-Oncology (EADO), the European Dermatology Forum (EDF) and the European Organization for Research and Treatment of Cancer (EORTC). Recommendations for the diagnosis and treatment of melanoma were developed on the basis of systematic literature research and consensus conferences. Cutaneous melanoma (CM) is the most dangerous form of skin tumor and accounts for 90 % of skin cancer mortality. The diagnosis of melanoma can be made clinically and must always be confirmed by dermoscopy. If melanoma is suspected, a histopathological examination is always required. Sequential digital dermoscopy and whole-body photography can be used in high-risk patients to improve the detection of early-stage melanoma. If available, confocal reflectance microscopy can also improve the clinical diagnosis in special cases. Melanoma is classified according to the 8th version of the American Joint Committee on Cancer classification. For thin melanomas up to a tumor thickness of 0.8 mm, no further diagnostic imaging is required. From stage IB, lymph node sonography is recommended, but no further imaging examinations. From stage IIB/C, whole-body examinations with computed tomography or positron emission tomography CT in combination with magnetic resonance imaging of the brain are recommended. From stage IIB/C and higher, a mutation test is recommended, especially for the BRAF V600 mutation. It is important to perform a structured follow-up to detect relapses and secondary primary melanomas as early as possible. A stage-based follow-up regimen is proposed, which in the experience of the guideline group covers the optimal requirements, although further studies may be considered. This guideline is valid until the end of 2026
A Multi-Media Q Methodology Investigation of the Degrowth Concept Among Young Citizens
No full textInternational audienceThe acceleration of research efforts dedicated to degrowth has been noticeable since 2012, along with a growing public interest. While many definitions of the degrowth notion exist, Schneider et al. (2010) define it as “an equitable downscaling of production and consumption”. Many views and discourses on degrowth arise but we can wonder to what extent people perceive different aspects of degrowth and its implications. These views and representations of the concept can be sketched by verbal, visual or even auditory stimuli. For that reason, we describe a two-part multi-media Q-methodological investigation of degrowth based on statements, pictures and sounds. In the first part, citizens trained in sustainable development project management, completed three Q sorts with separate Q sets each comprising of statements, pictures or sounds. In the second part, a different set of participants completed a follow-up study with just a picture Q set. Eight subjective views of degrowth were identified: institutional, idealistic, back to nature and pacifist, consumption-aware, activist, analytical realistic, socio-degrowth and holistic. Two of them were captured only though non-verbal stimuli
Wildfire Smoke Exposure and Incident Dementia
No full textInternational audienceImportance Long-term exposure to total fine particulate matter (PM 2.5 ) is a recognized dementia risk factor, but less is known about wildfire-generated PM 2.5 , an increasingly common PM 2.5 source. Objective To assess the association between long-term wildfire and nonwildfire PM 2.5 exposure and risk of incident dementia. Design, Setting, and Participants This open cohort study was conducted using January 2008 to December 2019 electronic health record (EHR) data among members of Kaiser Permanente Southern California (KPSC), which serves 4.7 million people across 10 California counties. KPSC members aged 60 years or older were eligible for inclusion. Members were excluded if they did not meet eligibility criteria, if they had a dementia diagnosis before cohort entry, or if EHR data lacked address information. Data analysis was conducted from May 2023 to May 2024. Exposures Three-year rolling mean wildfire and nonwildfire PM 2.5 in member census tracts from January 2006 to December 2019, updated quarterly and estimated via monitoring and remote-sensing data and statistical techniques. Main Outcome and Measures The primary outcome was incident dementia, identified using diagnostic codes in the EHR. Odds of dementia diagnoses associated with 3-year mean wildfire and nonwildfire PM 2.5 exposure were estimated using a discrete-time approach with pooled logistic regression. Models adjusted for age, sex, race and ethnicity (considered as a social construct rather than as a biological determinant), marital status, smoking status, calendar year, and census tract–level poverty and population density. Stratified models assessed effect measure modification by age, sex, race and ethnicity, and census tract–level poverty. Results Among 1.64 million KPSC members aged 60 years or older during the study period, 1 223 107 members were eligible for inclusion in this study. The study population consisted of 644 766 female members (53.0%). In total, 319 521 members identified as Hispanic (26.0%), 601 334 members identified as non-Hispanic White (49.0%), and 80 993 members received a dementia diagnosis during follow-up (6.6%). In adjusted models, a 1-μg/m 3 increase in the 3-year mean of wildfire PM 2.5 exposure was associated with an 18% increase in the odds of dementia diagnosis (odds ratio [OR], 1.18; 95% CI, 1.03-1.34). In comparison, a 1-μg/m 3 increase in nonwildfire PM 2.5 exposure was associated with a 1% increase (OR, 1.01; 95% CI, 1.01-1.02). For wildfire PM 2.5 exposure, associations were stronger among members less than 75 years old upon cohort entry, members from racially minoritized subgroups, and those living in high-poverty vs low-poverty census tracts. Conclusions and Relevance In this cohort study, after adjusting for measured confounders, long-term exposure to wildfire and nonwildfire PM 2.5 over a 3-year period was associated with dementia diagnoses. As the climate changes, interventions focused on reducing wildfire PM 2.5 exposure may reduce dementia diagnoses and related inequities
On the Set-Estimation of Uncertain Max-Plus Linear Systems
No full textInternational audienceThe paper focuses on the set-estimation for uncertain Max-Plus Linear systems, with bounded random parameters. This estimation process involves determining the conditional reach set, which is a compact set of all possible states that can be reached from a previous set through the transition model (dynamics) and can lead to the observed measurements through the observation model. In the context of Bayesian estimation theory, this set represents the support of the posterior probability density function of the system's state. We compare two approaches, a disjunctive approach, presented in literature, and a concise approach, presented as a contribution of this paper, to exactly compute this set. Even if both approaches are with an exponential theoretical complexity, it is shown that the concise approach is more efficient
Pierre Emmanuel : « La vie terrestre ». Visages d’une oeuvre et d’une vie
No full textActes du colloque Pierre Emmanuel du Centenaire (organisé à l’Université Paris-Sorbonne par le Centre de Recherche Pierre Emmanuel, l’Association des Amis de Pierre Emmanuel et le CERIEC de l’Université d’Angers, le 10 décembre 2016) et des autres manifestations du centenaireInternational audienc
Motivic, logarithmic, and topological Milnor fibrations
No full textInternational audienceWe compare the topological Milnor fibration and the motivic Milnor fibre of a regular complex function with only normal crossing singularities by introducing their common extension: the complete Milnor fibration. We give two equivalent constructions: the first one extending the classical Kato-Nakayama log-space and the second one, more geometric, based on the real oriented multigraph construction, a version of the real oriented deformation to the normal cone. In particular we recover A'Campo's model of the topological Milnor fibration, by quotienting the motivic Milnor fibration with suitable powers of , and show that it determines the classical motivic Milnor fibre.We give precise formulae expressing how the introduced objects change under blowings-up thus showing, in particular, that the motivic Milnor fibre is well-defined as an element in a Grothendieck ring and not merely in its localisation
Comparaison des processus de sublimation de glaces de CO et d'HO lors du dégel de pergélisolimplications pour les processus de surface martiens
No full textInternational audienceComparison of CO2 and H2O ice sublimation processes during permafrost thaw - implications for Martian surface processesWe conducted the first experimental study on the formation of molards through sublimation processes. On Earth, permafrost molards are cones of loose debris found in landslide deposits, which can be used as indicators of permafrost retreat in mountainous regions (Morino et al., EPSL 2019). Molard candidates have also been identified on Mars, in the ejecta flows of the billion years old Hale crater. These structures exhibit a morphology and spatial distribution similar to those of terrestrial molards (Morino et al., Icarus 2022). Unlike on Earth, these Martian molards likely formed through sublimation, since liquid water is not stable there (Harbele et al., JGR 2001).To examine how molards formed by sublimation might differ from those formed by melting, we created cylindrical blocks (Ø13 cm) of frozen sediment composed of either H₂O or CO₂ ice, which we then degrade on a horizontal board in a Mars simulation chamber. We quantified the volume transport during the degradation phase using a time-lapse photogrammetry system, taking images every 15 minutes. We carried out experiments for both types of ice, under Earth and Mars pressures, using three types of sediment.We successfully recreated cone-shaped morphologies resembling terrestrial permafrost molards, with both CO₂ and H₂O ice, under Martian pressure.We found that the gas flux produced by ice sublimation causes main morphological differences across the experiments, especially for the finest sediments. We deduce that the higher the gas production, the more likely the grains are to be ejected rather than simply by falling. Our results reveal that sublimation can alter expected morphologies when the gas flux is sufficient to transport sediment. This has implications for interpreting sublimation pit morphologies on Mars and other planetary bodies where sublimation is dominant (Mangold, Geomorphology 2011).Nous avons réalisé la première étude expérimentale sur la formation de molards par des processus de sublimation. Sur Terre, les molards induits par la dégradation du pergélisol sont des cônes de débris meubles présents dans les dépôts de glissements de terrain, qui peuvent être utilisés comme indicateurs du recul du pergélisol en montagne (Morino et al., EPSL 2019). Des candidats molards ont également été identifiés sur Mars, dans les écoulements d’éjectas du cratère Hale, vieux d’un milliard d’années. Ces structures présentent une morphologie et une distribution spatiale similaires à celles des molards terrestres (Morino et al., Icarus 2022). Contrairement à la Terre, ces molards martiens se seraient vraisemblablement formés par sublimation, car l’eau n’est pas stable sous forme liquide (Harbele et al., JGR 2001).Afin d’examiner comment les molards formés par sublimation pourraient différer de ceux formés par fonte, nous avons créé des blocs cylindriques (Ø13 cm) de sédiment gelé composés de glace H₂O ou CO₂, que nous avons laissés se dégrader sur une planche horizontale dans une chambre martienne. Nous avons quantifié le transport de volume durant la phase de dégradation à l’aide d’un système de photogrammétrie en time-lapse, avec une prise d’image toutes les 15 minutes. Nous avons réalisé des expériences pour les deux types de glace, sous pressions terrestre et martienne, avec trois types de sédiments.Nous avons réussi à recréer des morphologies coniques ressemblant aux molards de pergélisol terrestre, avec de la glace de CO₂ et d’H₂O, sous pression martienne.Nous avons constaté que, pour la sublimation de la glace, le débit de gaz résultant entraînait la plus grande différence morphologique entre les expériences, en particulier pour les sédiments les plus fins. Nous en déduisons que plus la production de gaz est élevée, plus les grains ont tendance à être éjectés, plutôt qu’à simplement s’effondrer. Nos résultats révèlent que la sublimation peut modifier les morphologies attendues lorsque le flux de gaz est capable d’emporter les sédiments. Cela a des implications pour l’interprétation des morphologies de puits de sublimation sur Mars et sur d’autres corps planétaires où la sublimation est dominante (Mangold, Geomorphology 2011)
Controls on CaCO3 Polymorphism: From Laboratory Precipitation to Biomineralization across Geological Time
No full textInternational audienceCalcium carbonate (CaCO3) forms various mineral polymorphs, including calcite, aragonite, and vaterite, each with distinct physicochemical properties. To benefit from these properties, marine organisms have evolved (some) control on the polymorphs from which their biomineral structures are built. This is achieved by modulating the conditions at their calcification sites and the nature of functional organic macromolecules that can serve as templates for carbonate crystallization. Environmental factors, such as seawater chemistry and ocean acidification, also affect polymorph selection, impacting organisms’ calcification pathways. Across geologic time, mass extinction events have influenced evolutionary-scale skeletal mineralogy trends. The organismal controls on CaCO3 polymorphism have significant implications for ecological and industrial applications, offering insights into the development of environmentally friendly materials with tailored properties
Les livres à venir : la bibliothèque « virtuelle » de François Grudé de La Croix du Maine
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Reusing clinical trial data to consolidate and advance medical knowledge
No full textInternational audienceWhile data sharing holds great potential to maximize the value of research and reduce waste, these benefits can only be fully realized if shared data are also effectively reused. Yet data reuse remains limited, and there is a notable lack of clear guidelines to support data reusers. Reusing existing data enables a wide range of valuable activities, including validating previous findings, identifying errors, conducting individual patient data meta-analyses, performing secondary analyses, and developing or testing new methods. However, the validity of such work depends on strict adherence to reproducible research practices-arguably even more so in the context of secondary use. Data reuse also involves practical constraints and specific challenges, such as addressing feasibility issues, that must be anticipated and managed from the outset. Researchers should remain aware of these considerations throughout the entire lifecycle of a reuse study. Ideally, this process should be supported by hands-on training tailored to the specific demands of data reuse. To that end, we propose a set of guiding principles to foster responsible and meaningful reuse of existing datasets-including, but not limited to, assembling a skilled multidisciplinary team, anticipating infrastructure and interoperability challenges, maintaining transparency throughout the research process, and incentivizing all stakeholders involved