55 research outputs found

    Appréhender le stock de métal monnayé au ive siÚcle aprÚs J.-C.

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    Parmi les thĂ©matiques abordĂ©es en numismatique Ă  l’aide de l’archĂ©omĂ©trie, les recherches spĂ©cifiques sur le stock de mĂ©tal monnayĂ© au ive siĂšcle s’avĂšrent fascinantes mais dĂ©licates. Afflux de nouvelles ressources mĂ©talliques, refontes volontaires de monnaies : tous ces phĂ©nomĂšnes sont de grande consĂ©quence pour les monnayages produits dans les diffĂ©rents ateliers de l’Empire romain tardif. Certaines donnĂ©es de ce type sont mesurables. Les alliages mĂ©talliques (donc ici monĂ©taires) contiennent en effet des Ă©lĂ©ments mineurs ou en traces, constituant la « carte d’identité » de l’approvisionnement des ateliers monĂ©taires. Il y a 10 ans Isabelle Bollard et Jean-NoĂ«l Barrandon rĂ©unissaient plusieurs analyses de monnaies en alliage cuivreux Ă©mises au cours du ive siĂšcle. Nos propres observations, obtenues dans le cadre d’un projet de recherche financĂ© par la rĂ©gion Normandie (intitulĂ© FANUM), sur 14 528 monnaies (nummi) de la pĂ©riode constantinienne contenues dans un trĂ©sor dĂ©couvert fortuitement Ă  Saint-Germain-de-Varreville (Manche), nous ont incitĂ©s Ă  reprendre, de façon plus approfondie, l’étude des alliages utilisĂ©s au cours de cette pĂ©riode, en portant notamment notre attention sur les teneurs en or et en argent. En effet, la grande variĂ©tĂ© des ateliers reprĂ©sentĂ©s au sein du trĂ©sor favorisait idĂ©alement une telle enquĂȘte. Le choix de la fluorescence X portable a permis d’élaborer un protocole d’analyse prĂ©cis et adaptĂ© Ă  un grand nombre de monnaies. L’exploitation de 774 analyses rĂ©alisĂ©es sur des nummi frappĂ©s dans les ateliers occidentaux a permis de complĂ©ter les travaux antĂ©rieurs, mais Ă©galement de mettre en Ă©vidence l’utilisation de stocks mĂ©talliques diffĂ©rents Ă  partir des annĂ©es 320.Among the thematics studied in numismatics using archeometry, specific research on the stock of metal struck in the 4th century turns out to be fascinating but complex. Influx of new metallic resources, voluntary recasts of coins: these phenomena have great consequences for the coinage produced in all the workshops throughout the late Roman Empire. Some of these data can be measurable. Metallic alloys (coins in this case) contain minor or trace elements that constitute a kind of “identity card” for the supply of monetary workshops. Ten years ago, Isabelle Bollard and Jean-NoĂ«l Barrandon collected several analyzes of bronzes struck during the 4th century. Our own observations, obtained within the FANUM project, funded by the Normandy region, on 14 528 coins (nummi) of the Constantinian period, contained in a fortuitously discovered treasure in Saint-Germain-de-Varreville (Manche) have motivated a thorough new study of the alloys used during this period, focusing on the traces of gold and silver. Indeed, the variety of workshops represented in the treasure has encouraged such an inquiry. The choice of portable X-ray fluorescence has enabled to develop a protocol of analysis adapted to a large number of coins. The use of 774 analyzes carried out on nummi struck in the Western workshops has completed previous works, but also enabled to highlight the use of different metal stocks from the 320s

    Multi-disciplinary investigation of fluid seepage on an unstable margin: The case of the Central Nile deep sea fan

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    We report on a multidisciplinary study of cold seeps explored in the Central Nile deep-sea fan of the Egyptian margin. Our approach combines in situ seafloor observation, geophysics, sedimentological data, measurement of bottom-water methane anomalies, pore-water and sediment geochemistry, and 230Th/U dating of authigenic carbonates. Two areas were investigated, which correspond to different sedimentary provinces. The lower slope, at ∌ 2100 m water depth, indicates deformation of sediments by gravitational processes, exhibiting slope-parallel elongated ridges and seafloor depressions. In contrast, the middle slope, at ∌ 1650 m water depth, exhibits a series of debris-flow deposits not remobilized by post-depositional gravity processes. Significant differences exist between fluid-escape structures from the two studied areas. At the lower slope, methane anomalies were detected in bottom-waters above the depressions, whereas the adjacent ridges show a frequent coverage of fractured carbonate pavements associated with chemosynthetic vent communities. Carbonate U/Th age dates (∌ 8 kyr BP), pore-water sulphate and solid phase sediment data suggest that seepage activity at those carbonate ridges has decreased over the recent past. In contrast, large (∌ 1 km2) carbonate-paved areas were discovered in the middle slope, with U/Th isotope evidence for ongoing carbonate precipitation during the Late Holocene (since ∌ 5 kyr BP at least). Our results suggest that fluid venting is closely related to sediment deformation in the Central Nile margin. It is proposed that slope instability leads to focused fluid flow in the lower slope and exposure of ‘fossil’ carbonate ridges, whereas pervasive diffuse flow prevails at the unfailed middle slope

    Relationship between moderate-to-vigorous, light intensity physical activity and sedentary behavior in a prospective cohort of older French adults: a 18-year follow-up of mortality and cardiovascular events ─ the PROOF cohort study

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    BackgroundIt is well documented that moderate-to-vigorous intensity physical activity (MVPA) is effective in the prevention of major chronic diseases. Even though the current international physical activity (PA) guidelines still mainly focus on MVPA, the topic of the most recent epidemiological studies has shifted from MVPA to light intensity physical activity (LPA), owing to the necessity of promoting all activities vs. sedentary behavior (SB). However, the evidence remains currently limited. Thus, the clarification of the effects of LPA and the close relationship with SB is crucial to promote public health.MethodPA and SB were assessed by a validated self-administered questionnaire (POPAQ) investigating 5 different types of PA during the 7 previous days. PA was measured in metabolic equivalent of task (MET)-h, which refers to the amount of energy (calories) expended per hour of PA. SB was measured in hour/day. Medical histories and examinations were taken during each clinical visit to determine clinical events. All-cause mortality was established using the same procedure and by checking local death registries. The relationships between the intensity of PA (light, moderate to vigorous) and mortality and between the periods of SB and mortality or CV events were analyzed by splines and COX models, adjusted for sex and year of birth.ResultsFrom the 1011 65-year-old subjects initially included in 2001 (60% women), the last 18-year follow-up has been currently completed since 2019. A total of 197 deaths (19.2%, including 77 CV deaths) and 195 CV events (19.3%) were reported. Averages (standard deviation) of MVPA, LPA and SB were, respectively, 1.2 h/d (0.3), 5.8 h/d (1.1), and 6.6 h/d (2.3). For all-cause deaths, as well as CV deaths, the splines were significant for LPA (p = 0.04 and p = 0.01), and MVPA (p < 0.001 and p < 0.001), but not for SB (p = 0.24 and p = 0.90). There was a significant reduction in CV events when SB was decreasing from 10.9 to 3.3 h/d.ConclusionThe PROOF cohort study shows a clear dose–response between the dose of LPA, MVPA, SB and risk of mortality. These findings provide additional evidence to support the inclusion of LPA in future PA guidelines

    Multidisciplinary investigation on cold seeps with vigorous gas emissions in the Sea of Marmara (MarsiteCruise): Strategy for site detection and sampling and first scientific outcome

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    MarsiteCruise was undertaken in October/November 2014 in the Sea of Marmara to gain detailed insight into the fate of fluids migrating within the sedimentary column and partially released into the water column. The overall objective of the project was to achieve a more global understanding of cold-seep dynamics in the context of a major active strike-slip fault. Five remotely operated vehicle (ROV) dives were performed at selected areas along the North Anatolian Fault and inherited faults. To efficiently detect, select and sample the gas seeps, we applied an original procedure. It combines sequentially (1) the acquisition of ship-borne multibeam acoustic data from the water column prior to each dive to detect gas emission sites and to design the tracks of the ROV dives, (2) in situ and real-time Raman spectroscopy analysis of the gas stream, and (3) onboard determination of molecular and isotopic compositions of the collected gas bubbles. The in situ Raman spectroscopy was used as a decision-making tool to evaluate the need for continuing with the sampling of gases from the discovered seep, or to move to another one. Push cores were gathered to study buried carbonates and pore waters at the surficial sediment, while CTD-Rosette allowed collecting samples to measure dissolved-methane concentration within the water column followed by a comparison with measurements from samples collected with the submersible Nautile during the Marnaut cruise in 2007. Overall, the visited sites were characterized by a wide diversity of seeps. CO2- and oil-rich seeps were found at the westernmost part of the sea in the Tekirdag Basin, while amphipods, anemones and coral populated the sites visited at the easternmost part in the Cinarcik Basin. Methane-derived authigenic carbonates and bacterial mats were widespread on the seafloor at all sites with variable size and distributions. The measured methane concentrations in the water column were up to 377 ÎŒmol, and the dissolved pore-water profiles indicated the occurrence of sulfate depleting processes accompanied with carbonate precipitation. The pore-water profiles display evidence of biogeochemical transformations leading to the fast depletion of seawater sulfate within the first 25-cm depth of the sediment. These results show that the North Anatolian Fault and inherited faults are important migration paths for fluids for which a significant part is discharged into the water column, contributing to the increase of methane concentration at the bottom seawater and favoring the development of specific ecosystems

    The FANCM:p.Arg658* truncating variant is associated with risk of triple-negative breast cancer

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    Abstract: Breast cancer is a common disease partially caused by genetic risk factors. Germline pathogenic variants in DNA repair genes BRCA1, BRCA2, PALB2, ATM, and CHEK2 are associated with breast cancer risk. FANCM, which encodes for a DNA translocase, has been proposed as a breast cancer predisposition gene, with greater effects for the ER-negative and triple-negative breast cancer (TNBC) subtypes. We tested the three recurrent protein-truncating variants FANCM:p.Arg658*, p.Gln1701*, and p.Arg1931* for association with breast cancer risk in 67,112 cases, 53,766 controls, and 26,662 carriers of pathogenic variants of BRCA1 or BRCA2. These three variants were also studied functionally by measuring survival and chromosome fragility in FANCM−/− patient-derived immortalized fibroblasts treated with diepoxybutane or olaparib. We observed that FANCM:p.Arg658* was associated with increased risk of ER-negative disease and TNBC (OR = 2.44, P = 0.034 and OR = 3.79; P = 0.009, respectively). In a country-restricted analysis, we confirmed the associations detected for FANCM:p.Arg658* and found that also FANCM:p.Arg1931* was associated with ER-negative breast cancer risk (OR = 1.96; P = 0.006). The functional results indicated that all three variants were deleterious affecting cell survival and chromosome stability with FANCM:p.Arg658* causing more severe phenotypes. In conclusion, we confirmed that the two rare FANCM deleterious variants p.Arg658* and p.Arg1931* are risk factors for ER-negative and TNBC subtypes. Overall our data suggest that the effect of truncating variants on breast cancer risk may depend on their position in the gene. Cell sensitivity to olaparib exposure, identifies a possible therapeutic option to treat FANCM-associated tumors

    A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

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    Abstract: Breast cancer (BC) risk for BRCA1 and BRCA2 mutation carriers varies by genetic and familial factors. About 50 common variants have been shown to modify BC risk for mutation carriers. All but three, were identified in general population studies. Other mutation carrier-specific susceptibility variants may exist but studies of mutation carriers have so far been underpowered. We conduct a novel case-only genome-wide association study comparing genotype frequencies between 60,212 general population BC cases and 13,007 cases with BRCA1 or BRCA2 mutations. We identify robust novel associations for 2 variants with BC for BRCA1 and 3 for BRCA2 mutation carriers, P < 10−8, at 5 loci, which are not associated with risk in the general population. They include rs60882887 at 11p11.2 where MADD, SP11 and EIF1, genes previously implicated in BC biology, are predicted as potential targets. These findings will contribute towards customising BC polygenic risk scores for BRCA1 and BRCA2 mutation carriers

    A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

    Get PDF
    Breast cancer (BC) risk for BRCA1 and BRCA2 mutation carriers varies by genetic and familial factors. About 50 common variants have been shown to modify BC risk for mutation carriers. All but three, were identified in general population studies. Other mutation carrier-specific susceptibility variants may exist but studies of mutation carriers have so far been underpowered. We conduct a novel case-only genome-wide association study comparing genotype frequencies between 60,212 general population BC cases and 13,007 cases with BRCA1 or BRCA2 mutations. We identify robust novel associations for 2 variants with BC for BRCA1 and 3 for BRCA2 mutation carriers, P < 10−8, at 5 loci, which are not associated with risk in the general population. They include rs60882887 at 11p11.2 where MADD, SP11 and EIF1, genes previously implicated in BC biology, are predicted as potential targets. These findings will contribute towards customising BC polygenic risk scores for BRCA1 and BRCA2 mutation carriers

    Étude de la dĂ©tonation de composĂ©s endothermiques gazeux

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    Les célérités de détonation de N3Cl gazeux, pur ou dilué par He, Ar et N2 sont mesurées dans des tubes cylindriques de différents diamÚtres en fonction de la pression initiale. Les célérités de détonation, extrapolées pour un tube de rayon infini, sont comparées aux célérités théoriques. Les limites de détonation de N3C1 et HN3 sont déterminées en fonction de la pression initiale, de la nature du diluant et du rayon du tube
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