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Communicating the risk of erosion: the effects of map-based communication on risk perception and affect
No full textInternational audienceThis study firstly aims to understand the impacts of map representations of coastal erosion on risk perception and affects of lay citizens. Secondly, it aims to study the effect of differing design of cartographic features on observation and interpretation of the message conveyed by different maps. Seven maps were presented to the participants (N = 50), varying according endogenous (abstraction, regalian cartridge) and exogenous characteristics (background, colours). A questionnaire interrogated risk perception and affect before and after observation, while eye-tracking data were recorded during the observation of each map. This experiment shows that communicating erosion risk by maps reduces perceived knowledge of risk but also reduces fear of the risk. The abstraction level significantly impacts observation patterns: correlation maps seem to guide visual attention in a more relevant way and to convey the message more clearly and effectively than other types of maps. But there is no influence of the other characteristics even if interviews show that colours seem to influence the message interpretatio
Combining morphological and molecular data to study past foraminiferal communities from a temperate coastal sediment core
No full textInternational audienceThis paper presents the results of a dual approach for assessing fossil benthic foraminiferal communities using both traditional morphology‐based analyses and sedimentary ancient DNA ( seda DNA) metabarcoding. The main objectives are to test the feasibility of seda DNA analyses to assess foraminiferal biodiversity in temperate shelf sediments (Le Croisic, France) off a major river system through time (Mid‐ to Late Holocene), and to point out the similarities and differences between classical and molecular methods. Our results show that, in contrast to the high foraminiferal diversity obtained from classic morphological analysis (over 140 taxa), the seda DNA analysis yielded only 20 operational taxonomic units (OTUs), which can be considered as equivalent to species. This strongly suggests a bad preservation of foraminiferal DNA downcore, likely due to the relatively ‘high’ temperature of the study site (14 °C) and/or to a methodological bias (e.g. insufficient amount of extracted sediment). In the total seda DNA, more than 90% of the reads were assigned to monothalamids (organic‐shelled foraminifera). In contrast, only a small number of mineralized taxa, highly dominant when identified using the morphological approach, were detected. This could be due to the naturally higher abundance of monothalamids compared to hard‐shelled foraminifera. While this abundance is reflected in seda DNA, it is not preserved in fossil morphological assemblages. In addition, the seda DNA of monothalamids might be easier to extract and their barcode to amplify than hard‐shelled foraminifera. The discrepancies between the microfossil data and seda DNA also include several species (e.g. Ammonia confertitesta (T6), Elphidium oceanense (S3), Nonionella sp. T4 and Nonionella sp. T6) that were rarely or not at all found in the fossil material which might be an indication of the presence of propagules, morphologically undetected in the >63 μm size fraction used. Finally, the presence of sequences of A. confertitesta and fossil specimens in the deep layers of the study cores suggests that this species, considered until now as recently invasive on the European coast, could have been present in the Atlantic coast several thousand years ago, much before any anthropogenic activity involving international shipping and commercial trades
Impaired cytotoxic function and exhausted phenotype of natural killer cells in VEXAS syndrome
No full textInternational audienceVEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is an autoinflammatory disorder caused by acquired somatic UBA1 mutations in hematopoietic stem cells, affecting peripheral myeloid and natural killer (NK) cells. Given the high rate of severe infections observed in VEXAS patients, we hypothesized that NK cell dysfunction contributes to this increased susceptibility. We conducted a comprehensive immune characterization of peripheral NK cells in patients with VEXAS (n=40), patients with autoinflammatory diseases without UBA1 mutations (n=22), and elderly gender-matched healthy controls (HCs) (n=16). Multiparameter phenotyping was performed using CyTOF, scRNAseq, whole blood stimulation assays and in vitro NK cell cytotoxic assay. Peripheral NK cells in VEXAS were quantitatively and qualitatively impaired. Mass cytometry revealed reduced frequencies of mature cytotoxic CD56dim NK cells and an expansion of the CD56high CD16dim subset. NK cells exhibited features of exhaustion, including increased PD-1 expression, and reduced levels of cytotoxic markers such as NKp46 and CD8α. scRNAseq analysis showed decreased signatures of cytotoxicity and IL-2 and IFN-γ production, alongside increased inflammatory signatures. Whole blood stimulation assays confirmed impaired IL-2, IFN-γ, and granzyme B production following TLR3, TLR4, and TLR7/TLR8 agonist stimulation. Extended NK phenotyping by flow cytometry confirmed reduced activating receptors' expression and impaired IFN-γ production in VEXAS. Moreover, in vitro UBA1 inhibitors impaired NK cell cytotoxic capacity and promote cell death. Finally, reduced NK cell frequencies were independently associated with an increased risk of severe infections. These findings suggest that NK cell dysfunction in VEXAS syndrome contributes to increased susceptibility to severe infections
The dithiocarbamate pesticides maneb and mancozeb disturb the metabolism of lipids and xenobiotics in an in vitro model of metabolic dysfunction-associated steatotic liver disease
No full textInternational audiencePesticides are increasingly recognized to be hepatotoxic, but less is known about their toxicity in metabolic dysfunction-associated steatotic liver disease (MASLD). Herein, differentiated HepaRG cells cultured for 2 weeks without (-FA) or with (+FA) a mixture of fatty acids were treated with different pesticides, including maneb and mancozeb, during the same period. While maneb and mancozeb did not induce neutral lipid accumulation in -FA-HepaRG cells, they worsened steatosis in +FA-HepaRG cells. MnCl 2 treatment reproduced these effects. Maneb or MnCl 2 impaired very low-density lipoprotein (VLDL) secretion and increased fatty acid uptake. Zinc supplementation restored VLDL secretion, reduced fatty acid uptake, and prevented steatosis worsening in +FA-Hep-aRG cells treated with mancozeb or MnCl 2 . Maneb, or MnCl 2, also reduced the mRNA expression and activity of several cytochromes P450 in +FA-and -FA-HepaRG cells. This was associated with impaired biotransformation of diazinon. These findings could have major pathophysiological consequences in dithiocarbamate-exposed individuals with MASL
REFINEMENT OF THE INFINITESIMAL VARIATION OF HODGE STRUCTURE: THE CASE OF CANONICAL CURVES
No full textLet C be a a smooth complex projective curve with the canonical line bundle K_C very ample.The paper studies the relation between the Kodaira-Spencer(K-S) classes and the geometryof C. A nonzero K-S class is viewed, via the differential of the period map, as a linear mapfrom to . The basic IVHS invariant is its kernel. The refinement is a distinguished filtration of that space. The refinement connects to the theory of special divisors, rational normal curves in the canonical embedding of the curve C. But it also reveals new features: quiver representations, Fano toric varieties, dimer models.The quiver emmerges from the construction and the properties of the refinement; the Fano variety arises from the graph underlying the quiver and is related to the Higgs structures. The graph becomes an important part of the theory: it connects to topics such as Topological Quantum field theory, moduli spaces of elliptic curves with marked points, modular curves, higher categorical structures
EXISTE-T-IL UNE GÉOGRAPHIE CULTURELLE MULTILINGUE EN FRANCOPHONIE ?
No full textInternational audienceUne proposition de réponse à partir d'une épistémologie analytique visant la cumulativité des savoirs, et de terrains urbains de Rennes Journées d'Etudes GÉOGRAPHIES CULTURELLES : LES VOIX D'ICI ET D'AILLEURS, Milan (Italie), 19-20 juin 2025 Commissions de l'Association internationale de géographie francophone (AIGF) « Géographies culturelles : représentations, récits et écritures du monde » et « Histoire de la pensée géographique » «</div
Monuments ou champs de bataille ? Honorer les morts hors de Bretagne durant l’entre-deux-guerres
No full textInternational audienceFar from Brittany, numerous monuments honor the Bretons who fell in combat. This is true in places like Attichy and Moulin-sous-Touvent in France, as well as in Belgium at Arsimont, Boesinghe, Maissin, Auvelais, and Saint-Charles-de-Potyze. These monuments quickly became part of the landscape of memorial tourism, which developed shortly after the war ended. But how are these distant monuments perceived by the Bretons? This article, focusing on the interwar period, explores the role of these monuments and the perspectives of visitors from the Armorican peninsula, whether pilgrims or tourists. Do these visits serve as a personal tribute to a fallen loved one, or are they part of a broader collective memory of the conflict?Loin de la Bretagne, de nombreux monuments honorent les Bretons tombés au combat. C’est le cas à Attichy et à Moulin-sous-Touvent ; ou encore en Belgique, à Arsimont, à Boesinghe, à Maissin, à Auvelais et à Saint-Charles-de-Potyze. Ces derniers trouvent très rapidement leur place dans le cadre du tourisme mémoriel qui se développe dès la fin du conflit. Or, comment ces édifices lointains sont-ils perçus par les Bretons ? Cet article, centré sur l'Entre-deux-guerres, examine le rôle de ces monuments et leurs visiteurs venus de la péninsule armoricaine, qu'ils soient pèlerins ou touristes. Ces visites relèvent-elles d’un hommage à un proche disparu ou participent-elles d'une mémoire collective du conflit
Repositioning of moxidectin: a promising approach in cutaneous leishmaniasis therapy
No full textInternational audienceZusammenfassung Hintergrund Eine erythematös‐ceruminöse Otitis externa (ECOE) wird häufig mit Malassezia spp. und einer mikrobiellen Imbalance in Zusammenhang gesehen. Hypothese/Ziele Eine Untersuchung der klinischen Leistung eines Ohrreinigers bei Hunden, die eine ECOE mit einem Malassezia spp. Überwachstum haben und eine Messung dieses Einflusses auf die Mikrobiota. Tiere Dreißig Hunde in Privatbesitz mit einer mild‐bis‐moderaten ECOE im Zusammenhang mit einem Malassezia spp. Überwachstum. Materialien und Methoden Pruritus Wert (PS), klinischer Wert (0‐3 Otitis Index Score [OTIS3]: basierend auf Sekretion, Erythem, Hyperplasie und Ulzeration) und zytologischer Wert (CS) wurden am Tag (D)0, D7 und D14 erfasst. Es wurden am D0 und D14 sterile Ohrtupfer verwendet, um eine Pilzkultur durchzuführen. DNA‐Extraktion und PCR‐Amplifizierung des 18 ITS und 16S rRNA‐Gens wurden durchgeführt, um die Zusammensetzung und die Veränderungen im otischen Mikrobiom zu evaluieren. Die Ohren wurden je nach Sekretionswert täglich, jeden zweiten Tag oder zweimal wöchentlich mit einem ceruminolytischen Ohrreiniger gereinigt. Ergebnisse Siebenundfünfzig Ohren (30 Hunde) beendeten die Studie. PS, OTIS‐3 und CS waren am D7 bzw D14 (‐45%, ‐43%, ‐60% bzw ‐77%, ‐66%, ‐76%; p < 0,0001 Wilcoxon Test) signifikant vermindert. Die Pilzkulturen waren am D0 nur bei 34 Ohren positiv ( Malassezia spp.) und bei allen Ohren am D14 negativ. Die Mykobiota Zusammensetzung war vor und nach der Behandlung signifikant verschieden, wobei die Diversität der Pilze am D14 im Vergleich zu D0 zunahm (Shannon Index; p < 0,003 Wilcoxon Test). Bei der bakteriellen Zusammensetzung gab es keine Veränderung. Schlussfolgerungen und klinische Bedeutung Im Falle einer ECOE mit Malassezia spp. Überwachstum zeigte der getestete Ohrreiniger einen positiven Einfluss auf die Dysbiose der Pilze und das Überwachstum der Malassezia spp.Cutaneous leishmaniasis presents a significant challenge to public health due to its diverse clinical manifestations, resistance development, and treatment-related adverse effects. Here, we examined the efficacy of ivermectin, moxidectin (MOX), afoxolaner, and permethrin against all stages of Leishmania tropica and THP-1 cells. We also assessed the potential for resistance acquisition after 15 rounds of artificial selection. To elucidate the mode of action of MOX, we employed RNA sequencing, molecular dynamics simulation, and chloride flux assays. Additionally, we evaluated the therapeutic index of MOX using the Galleria mellonella infection model. MOX demonstrated the highest selectivity index against leishmaniasis (promastigotes: 0.58 μM; amastigotes: 0.96 μM; host cells: 60.29 μM). Moreover, MOX exhibited the lowest resistance acquisition in both promastigotes and intracellular amastigotes after 15 rounds of artificial selection, with resistance ratios of 17.23 and 4.59, respectively. Post-exposure to MOX, differential gene expression profiles showed both stage-specific and stage-unspecific enrichment of gene families involved in crucial biological processes. Moreover, molecular dynamics simulations revealed a potential neutralizing effect of MOX on the chloride channel of L. tropica . Specifically, MOX binds to the selectivity filter, potentially disrupting the osmotic equilibrium and thereby killing the parasite. The in vivo introduction of MOX significantly inhibited the growth of L. tropica in G. mellonella larvae, resulting in decreased rates of mortality and melanization. These findings indicate that MOX is a promising candidate for the treatment of L. tropica infections, warranting further investigation and potential consideration for clinical use .RESUMEN Introducción La otitis externa eritematoceruminosa (ECOE) se asocia comúnmente con Malassezia spp . y desequilibrio microbiano. Hipótesis/Objetivo Evaluar el rendimiento clínico de un limpiador de oídos en perros con ECOE asociada a un sobrecrecimiento de Malassezia spp . y medir su impacto en la microbiota. Animales Treinta perros de propiedad privada con ECOE leve a moderada asociada a un sobrecrecimiento de Malassezia spp . Materiales y métodos Se evaluaron la puntuación de prurito (PS), la puntuación clínica (puntuación del índice de otitis [OTIS3] de 0 a 3 : basada en secreciones, eritema, hiperplasia y ulceración) y la puntuación citológica (CS) los días 0, 7 y 14. Se utilizaron hisopos óticos estériles los días D0 y D14 para extraer DNA del cultivo fúngico, y se realizó la amplificación por PCR de los genes 18 ITS y 16S rRNA para evaluar la composición y los cambios en el microbioma ótico. Los oídos se limpiaron con un limpiador cerumenolítico diariamente, cada dos días o dos veces por semana, según el nivel de secreción. Resultados Cincuenta y siete oídos (30 perros) completaron el estudio. PS, OTIS‐3 y CS disminuyeron significativamente los días D7 y D14 (–45 %, –43 %, –60 % y –77 %, –66 %, –76 %, respectivamente ; p < 0,0001 prueba de Wilcoxon). El cultivo fúngico fue positivo ( Malassezia spp .) solo en 34 oídos el día D0 y negativo en todos los oídos el día D14. La composición de la micobiota fue significativamente diferente antes y después del tratamiento, con un aumento de la diversidad fúngica (índice de Shannon ; p < 0,003 prueba de Wilcoxon) en el día 14 en comparación con el día 0. No se observaron cambios en la composición bacteriana. Conclusiones y relevancia clínica En el caso de ECOE asociada con sobrecrecimiento de Malassezia spp ., el uso del limpiador ótico evaluado mostró un impacto positivo en la disbiosis fúngica y el sobrecrecimiento de Malassezia spp .La leishmaniose cutanée représente un défi majeur de santé publique en raison de la diversité de ses manifestations cliniques, du développement de résistances et des effets indésirables liés au traitement. Nous avons examiné l’efficacité de l’ivermectine, de la moxidectine (MOX), de l’afoxolaner et de la perméthrine contre tous les stades de Leishmania tropica et les cellules THP-1. Nous avons également évalué le potentiel d’acquisition de résistance après 15 cycles de sélection artificielle. Pour élucider le mode d’action de la MOX, nous avons utilisé le séquençage de l’ARN, la simulation de dynamique moléculaire et des dosages de flux de chlorure. De plus, nous avons évalué l’indice thérapeutique de la MOX à l’aide du modèle d’infection chez Galleria mellonella . La MOX a montré l’indice de sélectivité le plus élevé contre la leishmaniose (promastigotes : 0,58 μM; amastigotes : 0,96 μM; cellules hôtes : 60,29 μM). De plus, la MOX a montré la plus faible acquisition de résistance chez les promastigotes et les amastigotes intracellulaires après 15 cycles de sélection artificielle, avec des ratios de résistance respectivement de 17,23 et 4,59. Après exposition à la MOX, les profils d’expression génique différentiels ont montré un enrichissement spécifique et non spécifique au stade des familles de gènes impliquées dans des processus biologiques cruciaux. De plus, les simulations de dynamique moléculaire ont révélé un effet neutralisant potentiel de la MOX sur le canal chlorure de L. tropica . Plus précisément, la MOX se lie au filtre de sélectivité, perturbant potentiellement l’équilibre osmotique et tuant ainsi le parasite. L’introduction in vivo de MOX a significativement inhibé la croissance de L. tropica chez les larves de G. mellonella , entraînant une diminution des taux de mortalité et de mélanisation. Ces résultats indiquent que la moxidectine est un candidat prometteur pour le traitement des infections à L. tropica , justifiant des recherches plus approfondies et une éventuelle utilisation clinique.要約 背景 紅斑性耳垢性外耳道炎(ECOE)は一般的にマラセチア属と微生物の不均衡と関連している。 仮説/目的 本研究の目的は、マラセチア属真菌の過剰増殖に関連するECOEに罹患している犬におけるイヤークリーナーの臨床的性能を評価し、微生物叢への影響を測定することであった。 対象動物 マラセチア属真菌の過剰増殖を伴う軽度から中等度のECOEに罹患している30頭のオーナー所有犬。 材料と方法 掻痒スコア(PS)、臨床スコア(0‐3 Otitis Index Score [OTIS3]:分泌物、紅斑、過形成および潰瘍形成に基づく)および細胞学的スコア(CS)をDay(D)0、D7およびD14に評価した。D0およびD14に滅菌耳スワブを用いて真菌培養DNA抽出し、18ITSおよび16S rRNA遺伝子のPCR増幅を実施して、耳微生物叢の構成と変化を評価した。耳は分泌物スコアに応じて、毎日、隔日または週2回、耳垢溶解性イヤークリーナーで洗浄した。 結果 57の耳(30頭)が研究を完了した。PS、OTIS‐3およびCSは、D7およびD14で有意に減少した(それぞれ‐45%、‐43%、‐60%および‐77%、‐66%、‐76%；p<0.0001 Wilcoxon検定)。真菌培養はD0ではわずか34耳で陽性( Malassezia spp.)であったが、D14ではすべての耳で陰性であった。真菌叢の組成は治療前後で有意に異なり、D0と比較してD14では真菌の多様性(Shannon index; p < 0.003ウィルコクソン検定)が増加した。細菌組成に変化はなかった。 結論および臨床的妥当性 マラセチア属真菌の過剰増殖を伴うECOEの場合、試験したイヤークリーナーの使用は、真菌のディスバイオーシスおよびマラセチア属の過剰増殖に好影響を示した。Resumo Contexto A otite externa eritemato‐ceruminosa (OECE) é comumente associada à infecção por Malassezia spp. e ao desequilíbrio microbiano. Hipótese/Objetivo Avaliar o desempenho clínico de uma solução de limpeza auricular em cães com OECE associada ao supercrescimento de Malassezia spp. e mensurar seu impacto na microbiota. Animais Trinta cães de propriedade particular com OECE leve a moderada associada ao crescimento excessivo de Malassezia spp. Materiais e Métodos O escore de prurido (EP), o escore clínico (0‐3, Escore do Índice de Otite [OTIS3]: baseado em secreções, eritema, hiperplasia e ulceração) e o escore citológico (EC) foram avaliados no Dia (D)0, D7 e D14. Swabs auriculares estéreis foram utilizados no D0 e D14 para extração de DNA da cultura fúngica, e amplificação por PCR dos genes 18 ITS e 16S rRNA foi realizada para avaliar a composição e as alterações do microbioma ótico. As orelhas foram limpas com um limpador auricular ceruminolítico diariamente, em dias alternados ou duas vezes por semana, dependendo da do escore de secreção. Resultados Cinquenta e sete orelhas (30 cães) completaram o estudo. EP, OTIS‐3 e EC diminuíram significativamente nos dias 7 e 14 (–45%, –43%, –60% e –77%, –66%, –76%, respectivamente; p < 0,0001 no teste de Wilcoxon). A cultura fúngica foi positiva ( Malassezia spp.) em apenas 34 orelhas no dia 0 e negativa em todas as orelhas no dia 14. A composição da micobiota foi significativamente diferente antes e depois do tratamento, com aumento da diversidade fúngica (índice de Shannon; p < 0,003 no teste de Wilcoxon) no D14 em comparação ao D0. Não houve alteração na composição bacteriana. Conclusões e Relevância Clínica Em caso de OECE associada ao supercrescimento de Malassezia spp., o uso do limpador auricular testado demonstrou um impacto positivo na disbiose fúngica e no supercrescimento de Malassezia spp
Faute de la victime et aggravation de son préjudice (illustration en matière environnementale et agricole)
No full textCass. civ. 3, 5 juin 2025, n° 23-23.775 : Si la victime n’est pas tenue de limiter son préjudice dans l’intérêt du responsable, sa faute, lorsqu’elle a contribué à l’aggravation du dommage, diminue son droit à réparation