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139 Research products, page 1 of 14

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  • 2017-2021
  • French National Research Agency (ANR)
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  • Open Access English
    Authors: 
    Alleon, Julien; Bernard, Sylvain; Le Guillou, Corentin; Daval, Damien; Skouri-Pane, Feriel; Kuga, Maïa; Robert, François;
    Publisher: HAL CCSD
    Countries: France, Switzerland
    Project: CIHR , ANR | DECore (ANR-07-BLAN-0124), NSERC

    Reconstructing the original biogeochemistry of organic fossils requires quantifying the extent of the chemical transformations that they underwent during burial-induced maturation processes. Here, we performed laboratory experiments on chemically different organic materials in order to simulate the thermal maturation processes that occur during diagenesis. Starting organic materials were microorganisms and organic aerosols. Scanning transmission X-ray microscopy (STXM) was used to collect X-ray absorption near edge spectroscopy (XANES) data of the organic residues. Results indicate that even after having been submitted to 250 °C and 250 bars for 100 days, the molecular signatures of microorganisms and aerosols remain different in terms of nitrogen-to-carbon atomic ratio and carbon and nitrogen speciation. These observations suggest that burial-induced thermal degradation processes may not completely obliterate the chemical and molecular signatures of organic molecules. In other words, the present study suggests that organic molecular heterogeneities can withstand diagenesis and be recognized in the fossil record. Scientific Reports, 7 ISSN:2045-2322

  • Open Access
    Authors: 
    Xiao-Fei Kong; Rubén Martínez-Barricarte; J. Kennedy; Federico Mele; Tomi Lazarov; Elissa K. Deenick; Cindy S. Ma; Gaëlle Breton; Kimberly Lucero; David Langlais; +31 more
    Publisher: Springer Science and Business Media LLC
    Project: NIH | A genetic dissection of M... (5R01AI089970-02), NIH | Clinical Core (1U19AI118626-01), ANR | GENMSMD (ANR-16-CE17-0005), SNSF | Studies on T cell activat... (170213), ANR | IFNGPHOX (ANR-13-ISV3-0001), NIH | Transforming Translationa... (3UL1TR000043-07S1), EC | PREDICT (323183), NIH | Nramp1 in macrophage defe... (5R01AI035237-12), NIH | Genome-Wide Dissection of... (5R37AI095983-07)

    Human inborn errors of IFN-γ immunity underlie mycobacterial diseases. We describe patients with Mycobacterium bovis (BCG) disease who are homozygous for loss-of-function mutations of SPPL2A. This gene encodes a transmembrane protease that degrades the N-terminal fragment (NTF) of CD74 (HLA invariant chain) in antigen-presenting cells. The CD74 NTF therefore accumulates in the HLA class II+ myeloid and lymphoid cells of SPPL2a-deficient patients. This toxic fragment selectively depletes IL-12- and IL-23-producing CD1c+ conventional dendritic cells (cDC2s) and their circulating progenitors. Moreover, SPPL2a-deficient memory TH1* cells selectively fail to produce IFN-γ when stimulated with mycobacterial antigens in vitro. Finally, Sppl2a–/– mice lack cDC2s, have CD4+ T cells that produce small amounts of IFN-γ after BCG infection, and are highly susceptible to infection with BCG or Mycobacterium tuberculosis. These findings suggest that inherited SPPL2a deficiency in humans underlies mycobacterial disease by decreasing the numbers of cDC2s and impairing IFN-γ production by mycobacterium-specific memory TH1* cells. Primary immunodeficiency can predispose patients to mycobacterial disease. Casanova and colleagues identify novel human mutations in the enzyme SPPL2A that result in selective accumulation of CD74 in a dendritic cell subset and lead to their death and the failure to mount effective TH1 responses.

  • Open Access English
    Authors: 
    Combrisson, Etienne; Vallat, Raphael; Eichenlaub, Jean-Baptiste; O'Reilly, Christian; Lajnef, Tarek; Guillot, Aymeric; Ruby, Perrine; Jerbi, Karim;
    Publisher: Frontiers Media S.A.
    Countries: Switzerland, United States, France
    Project: ANR | Avenir L.S.E. (ANR-11-IDEX-0007), NSERC , ANR | CORTEX (ANR-11-LABX-0042)

    We introduce Sleep, a new Python open-source graphical user interface (GUI) dedicated to visualization, scoring and analyses of sleep data. Among its most prominent features are: (1) Dynamic display of polysomnographic data, spectrogram, hypnogram and topographic maps with several customizable parameters, (2) Implementation of several automatic detection of sleep features such as spindles, K-complexes, slow waves, and rapid eye movements (REM), (3) Implementation of practical signal processing tools such as re-referencing or filtering, and (4) Display of main descriptive statistics including publication-ready tables and figures. The software package supports loading and reading raw EEG data from standard file formats such as European Data Format, in addition to a range of commercial data formats. Most importantly, Sleep is built on top of the VisPy library, which provides GPU-based fast and high-level visualization. As a result, it is capable of efficiently handling and displaying large sleep datasets. Sleep is freely available (http://visbrain. org/sleep) and comes with sample datasets and an extensive documentation. Novel functionalities will continue to be added and open-science community efforts are expected to enhance the capacities of this module.

  • Open Access English
    Authors: 
    Aalseth, C. E.; Abdelhakim, S.; Acerbi, F.; Agnes, P.; Ajaj, R.; Albuquerque, I. F. M.; Alexander, T.; Alici, A.; Alton, A. K.; Amaudruz, P.; +190 more
    Countries: Poland, France, Spain, Italy, France, United Kingdom, France
    Project: NSF | Collaborative Research: R... (1242585), ANR | USPC (ANR-11-IDEX-0005), NSF | Particle Astrophysics wit... (1211308), NSF | Collaborative Research: A... (1004054), NSF | Collaborative Research: D... (1314483), NSF | MAX - Multi-ton Argon and... (0919363), NSF | Collaborative Research: D... (1314507), NSF | Collaborative Research: A... (1004072), ANR | UnivEarthS (ANR-10-LABX-0023)

    Large liquid argon detectors offer one of the best avenues for the detection of galactic weakly interacting massive particles (WIMPs) via their scattering on atomic nuclei. The liquid argon target allows exquisite discrimination between nuclear and electron recoil signals via pulse-shape discrimination of the scintillation signals. Atmospheric argon (AAr), however, has a naturally occurring radioactive isotope, $^{39}$Ar, a $\beta$ emitter of cosmogenic origin. For large detectors, the atmospheric $^{39}$Ar activity poses pile-up concerns. The use of argon extracted from underground wells, deprived of $^{39}$Ar, is key to the physics potential of these experiments. The DarkSide-20k dark matter search experiment will operate a dual-phase time projection chamber with 50 tonnes of radio-pure underground argon (UAr), that was shown to be depleted of $^{39}$Ar with respect to AAr by a factor larger than 1400. Assessing the $^{39}$Ar content of the UAr during extraction is crucial for the success of DarkSide-20k, as well as for future experiments of the Global Argon Dark Matter Collaboration (GADMC). This will be carried out by the DArT in ArDM experiment, a small chamber made with extremely radio-pure materials that will be placed at the centre of the ArDM detector, in the Canfranc Underground Laboratory (LSC) in Spain. The ArDM LAr volume acts as an active veto for background radioactivity, mostly $\gamma$-rays from the ArDM detector materials and the surrounding rock. This article describes the DArT in ArDM project, including the chamber design and construction, and reviews the background required to achieve the expected performance of the detector. Comment: 13 pages, 8 figures. Corresponding author: E. S\'anchez Garc\'ia

  • Open Access English
    Authors: 
    Jesús Revuelto; Grégoire Lecourt; Matthieu Lafaysse; Isabella Zin; Luc Charrois; Vincent Vionnet; Marie Dumont; Antoine Rabatel; Delphine Six; Thomas Condom; +3 more
    Publisher: HAL CCSD
    Country: France
    Project: ANR | EBONI (ANR-16-CE01-0006)

    This work presents an extensive evaluation of the Crocus snowpack model over a rugged and highly glacierized mountain catchment (Arve valley, Western Alps, France) from 1989 to 2015. The simulations were compared and evaluated using in-situ point snow depth measurements, in-situ seasonal and annual glacier surface mass balance, snow covered area evolution based on optical satellite imagery at 250 m resolution (MODIS sensor), and the annual equilibrium-line altitude of glaciers, derived from satellite images (Landsat, SPOT, and ASTER). The snowpack simulations were obtained using the Crocus snowpack model driven by the same, originally semi-distributed, meteorological forcing (SAFRAN) reanalysis using the native semi-distributed configuration, but also a fully distributed configuration. The semi-distributed approach addresses land surface simulations for discrete topographic classes characterized by elevation range, aspect, and slope. The distributed approach operates on a 250-m grid, enabling inclusion of terrain shadowing effects, based on the same original meteorological dataset. Despite the fact that the two simulations use the same snowpack model, being potentially subjected to same potential deviation from the parametrization of certain physical processes, the results showed that both approaches accurately reproduced the snowpack distribution over the study period. Slightly (although statistically significantly) better results were obtained by using the distributed approach. The evaluation of the snow cover area with MODIS sensor has shown, on average, a reduction of the Root Mean Squared Error (RMSE) from 15.2% with the semi-distributed approach to 12.6% with the distributed one. Similarly, surface glacier mass balance RMSE decreased from 1.475 m of water equivalent (W.E.) for the semi-distributed simulation to 1.375 m W.E. for the distribution. The improvement, observed with a much higher computational time, does not justify the recommendation of this approach for all applications however, for simulations that require a precise representation of snowpack distribution, the distributed approach is suggested.

  • Open Access English
    Authors: 
    Julia V. Seidel; Monika Lendl; Vincent Bourrier; David Ehrenreich; Romain Allart; S. G. Sousa; Heather M. Cegla; Xavier Bonfils; U. Conod; A. Grandjean; +10 more
    Project: SNSF | Exploring exoplanets with... (152721), SNSF | Observations d'atmosphère... (186765), FCT | UIDP/04434/2020 (UIDP/04434/2020), SNSF | Exploring exoplanets with... (184618), EC | FOUR ACES (724427), FCT | UID/FIS/04434/2019 (UID/FIS/04434/2019), SNSF | Exploring exoplanets with... (140649), FCT | UIDB/04434/2020 (UIDB/04434/2020), ANR | GIPSE (ANR-14-CE33-0018)

    WASP-127b is one of the puffiest exoplanets found to date, with a mass only $3.4$ Neptune masses, but a radius larger than Jupiter. It is also located at the border of the Neptune desert, which describes the lack of highly-irradiated Neptune-sized planets, and which remains poorly understood. Its large scale height and bright host star make the transiting WASP-127b a valuable target to characterise in transmission spectroscopy. We use combined EulerCam and TESS light curves to recalculate the system's parameters. Additionally, we present an in-depth search for sodium in four transit observations of WASP-127b, obtained as part of the Hot Exoplanet Atmosphere Resolved with Transit Spectroscopy (HEARTS) survey with the High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph. Two nights from this dataset were analysed independently by another team, claiming a detection of sodium incompatible with previous studies of data from both ground and space. We show that this large sodium detection is actually due to contamination from telluric sodium emissions and the low S/N in the core of the deep stellar sodium lines. When properly accounting for these effects, the previous sodium signal is reduced to an absorption of $0.46\pm0.20\%$ ($2.3\sigma$), which is compatible with analyses of WASP-127b transits carried out with other instruments. We can fit a Gaussian to the D2 line, however, the D1 line was not detected, indicating an unusual line ratio if sodium exists in the atmosphere. Follow-up of WASP-127 at both high-resolution and with high sensitivity will be required to firmly establish the presence of sodium and analyse its line shape. Comment: 11 pages, 11 figures, published in A&A

  • Open Access English
    Authors: 
    Chiara Uboldi; Marcos Sanles Sobrido; E. Bernard; Virginie Tassistro; Nathalie Herlin-Boime; Dominique Vrel; Sébastien Garcia-Argote; Stéphane Roche; Frédérique Magdinier; Gheorghe Dinescu; +7 more
    Publisher: MDPI AG
    Country: France
    Project: ANR | Amidex (ANR-11-IDEX-0001)

    International audience; Tungsten was chosen as a wall component to interact with the plasma generated by the International Thermonuclear Experimental fusion Reactor (ITER). Nevertheless, during plasma operation tritiated tungsten nanoparticles (W-NPs) will be formed and potentially released into the environment following a Loss-Of-Vacuum-Accident, causing occupational or accidental exposure. We therefore investigated, in the bronchial human-derived BEAS-2B cell line, the cytotoxic and epigenotoxic effects of two types of ITER-like W-NPs (plasma sputtering or laser ablation), in their pristine, hydrogenated, and tritiated forms. Long exposures (24 h) induced significant cytotoxicity, especially for the hydrogenated ones. Plasma W-NPs impaired cytostasis more severely than the laser ones and both types and forms of W-NPs induced significant micronuclei formation, as shown by cytokinesis-block micronucleus assay. Single DNA strand breaks, potentially triggered by oxidative stress, occurred upon exposure to W-NPs and independently of their form, as observed by alkaline comet assay. After 24 h it was shown that more than 50% of W was dissolved via oxidative dissolution. Overall, our results indicate that W-NPs can affect the in vitro viability of BEAS-2B cells and induce epigenotoxic alterations. We could not observe significant differences between plasma and laser W-NPs so their toxicity might not be triggered by the synthesis method.

  • Publication . Article . Other literature type . 2018
    Open Access English
    Authors: 
    Alessandro Genoni; Lukáš Bučinský; Nicolas Claiser; Julia Contreras-García; Birger Dittrich; Paulina M. Dominiak; Enrique Espinosa; Carlo Gatti; Paolo Giannozzi; Jean-Michel Gillet; +12 more
    Publisher: HAL CCSD
    Countries: Italy, France, Sweden, Italy
    Project: EC | MaX (676598), NSERC , SNSF | Physical and chemical pro... (160157), ANR | HalX-Bond (ANR-08-BLAN-0091), ANR | QuMacroRef (ANR-17-CE29-0005), ARC | Interatomic bonding in al... (FT110100427)

    International audience; Crystallography and quantum mechanics have always been tightly connected because reliable quantum mechanical models are needed to determine crystal structures. Due to this natural synergy, nowadays accurate distributions of electrons in space can be obtained from diffraction and scattering experiments. In the original definition of quantum crystallography (QCr) given by Massa, Karle and Huang, direct extraction of wavefunctions or density matrices from measured intensities of reflections or, conversely, ad hoc quantum mechanical calculations to enhance the accuracy of the crystallographic refinement are implicated. Nevertheless, many other active and emerging research areas involving quantum mechanics and scattering experiments are not covered by the original definition although they enable to observe and explain quantum phenomena as accurately and successfully as the original strategies. Therefore, we give an overview over current research that is related to a broader notion of QCr, and discuss options how QCr can evolve to become a complete and independent domain of natural sciences. The goal of this paper is to initiate discussions around QCr, but not to find a final definition of the field.

  • Open Access English
    Authors: 
    Andreea Manole; Stephanie Efthymiou; Emer O'Connor; Marisa I. Mendes; Matthew J. Jennings; Reza Maroofian; Indran Davagnanam; Kshitij Mankad; Maria Rodriguez Lopez; Vincenzo Salpietro; +82 more
    Publisher: Elsevier
    Countries: France, Netherlands, Turkey
    Project: WT | Exploring novel molecular... (109915), UKRI | MRC Centre for Neuromuscu... (G0601943), ANR | UNISTRA (ANR-10-IDEX-0002), WT | Strengthening the neuromu... (201064), EC | REVERSIBLECOX (309548), EC | HUCNC (249968)

    Aminoacyl-tRNA synthetases (ARSs) are ubiquitous, ancient enzymes that charge amino acids to cognate tRNA molecules, the essential first step of protein translation. Here, we describe 32 individuals from 21 families, presenting with microcephaly, neurodevelopmental delay, seizures, peripheral neuropathy, and ataxia, with de novo heterozygous and bi-allelic mutations in asparaginyl-tRNA synthetase (NARS1). We demonstrate a reduction in NARS1 mRNA expression as well as in NARS1 enzyme levels and activity in both individual fibroblasts and induced neural progenitor cells (iNPCs). Molecular modeling of the recessive c.1633C>T (p.Arg545Cys) variant shows weaker spatial positioning and tRNA selectivity. We conclude that de novo and bi-allelic mutations in NARS1 are a significant cause of neurodevelopmental disease, where the mechanism for de novo variants could be toxic gain-of-function and for recessive variants, partial loss-of-function.

  • Open Access English
    Authors: 
    Wilfried Thuiller; Dominique Gravel; Gentile Francesco Ficetola; Sébastien Lavergne; Tamara Münkemüller; Laura J. Pollock; Niklaus E. Zimmermann; Florent Mazel;
    Publisher: HAL CCSD
    Country: France
    Project: ANR | FutureWeb (ANR-18-EBI4-0009), SNSF | FutureWeb (184131)

    International audience; Aim: The positive effect of primary productivity on animal species richness is one of the most conspicuous ecological features on Earth. However, less is known about the relationship between ecosystems primary productivity and the evolutionary history of biota. Here, we analyse how global primary productivity relates to the phylogenetic structure of vertebrate assemblages, and to the distribution of the most distinct lineages and recently diversified clades.Location: Global.Taxon: Amphibians, birds and mammals.Methods: We calculated relative phylogenetic diversity (i.e. phylogenetic diversity corrected for species richness), standardized effect size of the richness of top 25% evolutionary distinct species and of top 25% species‐level lineage diversification rates. We related these three metrics to mean net primary productivity (NPP) at the global scale, and for each zoogeographic region. We also tested the influence of the spatial scaling of species pool on the overall analyses (global, hemispheric and zoogeographic regions‐based species pools).Results: Phylogenetic diversity (corrected for species richness) of the three taxa decreases with NPP (in contrast with species richness) and varies considerably in space. High productivity sites harbour more closely related species than low productivity sites consistently across zoogeographic zones. However, the phylogenetically most distinct species are also found in high productivity sites, while the top most rapidly diversifying lineages are found in the least productive sites. Modifying the spatial extent of the species pool did not affect the results much.Conclusions: Benign conditions in high productivity sites (a) result in denser niche packing and thus allow for the coexistence of many closely‐related species and (b) protect the persistence of evolutionary distinct species. Low productivity sites may harbour fewer, more distinct and temporarily more variable niches that allow maintenance of unique lineages for longer periods of time.

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The following results are related to Canada. Are you interested to view more results? Visit OpenAIRE - Explore.
139 Research products, page 1 of 14
  • Open Access English
    Authors: 
    Alleon, Julien; Bernard, Sylvain; Le Guillou, Corentin; Daval, Damien; Skouri-Pane, Feriel; Kuga, Maïa; Robert, François;
    Publisher: HAL CCSD
    Countries: France, Switzerland
    Project: CIHR , ANR | DECore (ANR-07-BLAN-0124), NSERC

    Reconstructing the original biogeochemistry of organic fossils requires quantifying the extent of the chemical transformations that they underwent during burial-induced maturation processes. Here, we performed laboratory experiments on chemically different organic materials in order to simulate the thermal maturation processes that occur during diagenesis. Starting organic materials were microorganisms and organic aerosols. Scanning transmission X-ray microscopy (STXM) was used to collect X-ray absorption near edge spectroscopy (XANES) data of the organic residues. Results indicate that even after having been submitted to 250 °C and 250 bars for 100 days, the molecular signatures of microorganisms and aerosols remain different in terms of nitrogen-to-carbon atomic ratio and carbon and nitrogen speciation. These observations suggest that burial-induced thermal degradation processes may not completely obliterate the chemical and molecular signatures of organic molecules. In other words, the present study suggests that organic molecular heterogeneities can withstand diagenesis and be recognized in the fossil record. Scientific Reports, 7 ISSN:2045-2322

  • Open Access
    Authors: 
    Xiao-Fei Kong; Rubén Martínez-Barricarte; J. Kennedy; Federico Mele; Tomi Lazarov; Elissa K. Deenick; Cindy S. Ma; Gaëlle Breton; Kimberly Lucero; David Langlais; +31 more
    Publisher: Springer Science and Business Media LLC
    Project: NIH | A genetic dissection of M... (5R01AI089970-02), NIH | Clinical Core (1U19AI118626-01), ANR | GENMSMD (ANR-16-CE17-0005), SNSF | Studies on T cell activat... (170213), ANR | IFNGPHOX (ANR-13-ISV3-0001), NIH | Transforming Translationa... (3UL1TR000043-07S1), EC | PREDICT (323183), NIH | Nramp1 in macrophage defe... (5R01AI035237-12), NIH | Genome-Wide Dissection of... (5R37AI095983-07)

    Human inborn errors of IFN-γ immunity underlie mycobacterial diseases. We describe patients with Mycobacterium bovis (BCG) disease who are homozygous for loss-of-function mutations of SPPL2A. This gene encodes a transmembrane protease that degrades the N-terminal fragment (NTF) of CD74 (HLA invariant chain) in antigen-presenting cells. The CD74 NTF therefore accumulates in the HLA class II+ myeloid and lymphoid cells of SPPL2a-deficient patients. This toxic fragment selectively depletes IL-12- and IL-23-producing CD1c+ conventional dendritic cells (cDC2s) and their circulating progenitors. Moreover, SPPL2a-deficient memory TH1* cells selectively fail to produce IFN-γ when stimulated with mycobacterial antigens in vitro. Finally, Sppl2a–/– mice lack cDC2s, have CD4+ T cells that produce small amounts of IFN-γ after BCG infection, and are highly susceptible to infection with BCG or Mycobacterium tuberculosis. These findings suggest that inherited SPPL2a deficiency in humans underlies mycobacterial disease by decreasing the numbers of cDC2s and impairing IFN-γ production by mycobacterium-specific memory TH1* cells. Primary immunodeficiency can predispose patients to mycobacterial disease. Casanova and colleagues identify novel human mutations in the enzyme SPPL2A that result in selective accumulation of CD74 in a dendritic cell subset and lead to their death and the failure to mount effective TH1 responses.

  • Open Access English
    Authors: 
    Combrisson, Etienne; Vallat, Raphael; Eichenlaub, Jean-Baptiste; O'Reilly, Christian; Lajnef, Tarek; Guillot, Aymeric; Ruby, Perrine; Jerbi, Karim;
    Publisher: Frontiers Media S.A.
    Countries: Switzerland, United States, France
    Project: ANR | Avenir L.S.E. (ANR-11-IDEX-0007), NSERC , ANR | CORTEX (ANR-11-LABX-0042)

    We introduce Sleep, a new Python open-source graphical user interface (GUI) dedicated to visualization, scoring and analyses of sleep data. Among its most prominent features are: (1) Dynamic display of polysomnographic data, spectrogram, hypnogram and topographic maps with several customizable parameters, (2) Implementation of several automatic detection of sleep features such as spindles, K-complexes, slow waves, and rapid eye movements (REM), (3) Implementation of practical signal processing tools such as re-referencing or filtering, and (4) Display of main descriptive statistics including publication-ready tables and figures. The software package supports loading and reading raw EEG data from standard file formats such as European Data Format, in addition to a range of commercial data formats. Most importantly, Sleep is built on top of the VisPy library, which provides GPU-based fast and high-level visualization. As a result, it is capable of efficiently handling and displaying large sleep datasets. Sleep is freely available (http://visbrain. org/sleep) and comes with sample datasets and an extensive documentation. Novel functionalities will continue to be added and open-science community efforts are expected to enhance the capacities of this module.

  • Open Access English
    Authors: 
    Aalseth, C. E.; Abdelhakim, S.; Acerbi, F.; Agnes, P.; Ajaj, R.; Albuquerque, I. F. M.; Alexander, T.; Alici, A.; Alton, A. K.; Amaudruz, P.; +190 more
    Countries: Poland, France, Spain, Italy, France, United Kingdom, France
    Project: NSF | Collaborative Research: R... (1242585), ANR | USPC (ANR-11-IDEX-0005), NSF | Particle Astrophysics wit... (1211308), NSF | Collaborative Research: A... (1004054), NSF | Collaborative Research: D... (1314483), NSF | MAX - Multi-ton Argon and... (0919363), NSF | Collaborative Research: D... (1314507), NSF | Collaborative Research: A... (1004072), ANR | UnivEarthS (ANR-10-LABX-0023)

    Large liquid argon detectors offer one of the best avenues for the detection of galactic weakly interacting massive particles (WIMPs) via their scattering on atomic nuclei. The liquid argon target allows exquisite discrimination between nuclear and electron recoil signals via pulse-shape discrimination of the scintillation signals. Atmospheric argon (AAr), however, has a naturally occurring radioactive isotope, $^{39}$Ar, a $\beta$ emitter of cosmogenic origin. For large detectors, the atmospheric $^{39}$Ar activity poses pile-up concerns. The use of argon extracted from underground wells, deprived of $^{39}$Ar, is key to the physics potential of these experiments. The DarkSide-20k dark matter search experiment will operate a dual-phase time projection chamber with 50 tonnes of radio-pure underground argon (UAr), that was shown to be depleted of $^{39}$Ar with respect to AAr by a factor larger than 1400. Assessing the $^{39}$Ar content of the UAr during extraction is crucial for the success of DarkSide-20k, as well as for future experiments of the Global Argon Dark Matter Collaboration (GADMC). This will be carried out by the DArT in ArDM experiment, a small chamber made with extremely radio-pure materials that will be placed at the centre of the ArDM detector, in the Canfranc Underground Laboratory (LSC) in Spain. The ArDM LAr volume acts as an active veto for background radioactivity, mostly $\gamma$-rays from the ArDM detector materials and the surrounding rock. This article describes the DArT in ArDM project, including the chamber design and construction, and reviews the background required to achieve the expected performance of the detector. Comment: 13 pages, 8 figures. Corresponding author: E. S\'anchez Garc\'ia

  • Open Access English
    Authors: 
    Jesús Revuelto; Grégoire Lecourt; Matthieu Lafaysse; Isabella Zin; Luc Charrois; Vincent Vionnet; Marie Dumont; Antoine Rabatel; Delphine Six; Thomas Condom; +3 more
    Publisher: HAL CCSD
    Country: France
    Project: ANR | EBONI (ANR-16-CE01-0006)

    This work presents an extensive evaluation of the Crocus snowpack model over a rugged and highly glacierized mountain catchment (Arve valley, Western Alps, France) from 1989 to 2015. The simulations were compared and evaluated using in-situ point snow depth measurements, in-situ seasonal and annual glacier surface mass balance, snow covered area evolution based on optical satellite imagery at 250 m resolution (MODIS sensor), and the annual equilibrium-line altitude of glaciers, derived from satellite images (Landsat, SPOT, and ASTER). The snowpack simulations were obtained using the Crocus snowpack model driven by the same, originally semi-distributed, meteorological forcing (SAFRAN) reanalysis using the native semi-distributed configuration, but also a fully distributed configuration. The semi-distributed approach addresses land surface simulations for discrete topographic classes characterized by elevation range, aspect, and slope. The distributed approach operates on a 250-m grid, enabling inclusion of terrain shadowing effects, based on the same original meteorological dataset. Despite the fact that the two simulations use the same snowpack model, being potentially subjected to same potential deviation from the parametrization of certain physical processes, the results showed that both approaches accurately reproduced the snowpack distribution over the study period. Slightly (although statistically significantly) better results were obtained by using the distributed approach. The evaluation of the snow cover area with MODIS sensor has shown, on average, a reduction of the Root Mean Squared Error (RMSE) from 15.2% with the semi-distributed approach to 12.6% with the distributed one. Similarly, surface glacier mass balance RMSE decreased from 1.475 m of water equivalent (W.E.) for the semi-distributed simulation to 1.375 m W.E. for the distribution. The improvement, observed with a much higher computational time, does not justify the recommendation of this approach for all applications however, for simulations that require a precise representation of snowpack distribution, the distributed approach is suggested.

  • Open Access English
    Authors: 
    Julia V. Seidel; Monika Lendl; Vincent Bourrier; David Ehrenreich; Romain Allart; S. G. Sousa; Heather M. Cegla; Xavier Bonfils; U. Conod; A. Grandjean; +10 more
    Project: SNSF | Exploring exoplanets with... (152721), SNSF | Observations d'atmosphère... (186765), FCT | UIDP/04434/2020 (UIDP/04434/2020), SNSF | Exploring exoplanets with... (184618), EC | FOUR ACES (724427), FCT | UID/FIS/04434/2019 (UID/FIS/04434/2019), SNSF | Exploring exoplanets with... (140649), FCT | UIDB/04434/2020 (UIDB/04434/2020), ANR | GIPSE (ANR-14-CE33-0018)

    WASP-127b is one of the puffiest exoplanets found to date, with a mass only $3.4$ Neptune masses, but a radius larger than Jupiter. It is also located at the border of the Neptune desert, which describes the lack of highly-irradiated Neptune-sized planets, and which remains poorly understood. Its large scale height and bright host star make the transiting WASP-127b a valuable target to characterise in transmission spectroscopy. We use combined EulerCam and TESS light curves to recalculate the system's parameters. Additionally, we present an in-depth search for sodium in four transit observations of WASP-127b, obtained as part of the Hot Exoplanet Atmosphere Resolved with Transit Spectroscopy (HEARTS) survey with the High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph. Two nights from this dataset were analysed independently by another team, claiming a detection of sodium incompatible with previous studies of data from both ground and space. We show that this large sodium detection is actually due to contamination from telluric sodium emissions and the low S/N in the core of the deep stellar sodium lines. When properly accounting for these effects, the previous sodium signal is reduced to an absorption of $0.46\pm0.20\%$ ($2.3\sigma$), which is compatible with analyses of WASP-127b transits carried out with other instruments. We can fit a Gaussian to the D2 line, however, the D1 line was not detected, indicating an unusual line ratio if sodium exists in the atmosphere. Follow-up of WASP-127 at both high-resolution and with high sensitivity will be required to firmly establish the presence of sodium and analyse its line shape. Comment: 11 pages, 11 figures, published in A&A

  • Open Access English
    Authors: 
    Chiara Uboldi; Marcos Sanles Sobrido; E. Bernard; Virginie Tassistro; Nathalie Herlin-Boime; Dominique Vrel; Sébastien Garcia-Argote; Stéphane Roche; Frédérique Magdinier; Gheorghe Dinescu; +7 more
    Publisher: MDPI AG
    Country: France
    Project: ANR | Amidex (ANR-11-IDEX-0001)

    International audience; Tungsten was chosen as a wall component to interact with the plasma generated by the International Thermonuclear Experimental fusion Reactor (ITER). Nevertheless, during plasma operation tritiated tungsten nanoparticles (W-NPs) will be formed and potentially released into the environment following a Loss-Of-Vacuum-Accident, causing occupational or accidental exposure. We therefore investigated, in the bronchial human-derived BEAS-2B cell line, the cytotoxic and epigenotoxic effects of two types of ITER-like W-NPs (plasma sputtering or laser ablation), in their pristine, hydrogenated, and tritiated forms. Long exposures (24 h) induced significant cytotoxicity, especially for the hydrogenated ones. Plasma W-NPs impaired cytostasis more severely than the laser ones and both types and forms of W-NPs induced significant micronuclei formation, as shown by cytokinesis-block micronucleus assay. Single DNA strand breaks, potentially triggered by oxidative stress, occurred upon exposure to W-NPs and independently of their form, as observed by alkaline comet assay. After 24 h it was shown that more than 50% of W was dissolved via oxidative dissolution. Overall, our results indicate that W-NPs can affect the in vitro viability of BEAS-2B cells and induce epigenotoxic alterations. We could not observe significant differences between plasma and laser W-NPs so their toxicity might not be triggered by the synthesis method.

  • Publication . Article . Other literature type . 2018
    Open Access English
    Authors: 
    Alessandro Genoni; Lukáš Bučinský; Nicolas Claiser; Julia Contreras-García; Birger Dittrich; Paulina M. Dominiak; Enrique Espinosa; Carlo Gatti; Paolo Giannozzi; Jean-Michel Gillet; +12 more
    Publisher: HAL CCSD
    Countries: Italy, France, Sweden, Italy
    Project: EC | MaX (676598), NSERC , SNSF | Physical and chemical pro... (160157), ANR | HalX-Bond (ANR-08-BLAN-0091), ANR | QuMacroRef (ANR-17-CE29-0005), ARC | Interatomic bonding in al... (FT110100427)

    International audience; Crystallography and quantum mechanics have always been tightly connected because reliable quantum mechanical models are needed to determine crystal structures. Due to this natural synergy, nowadays accurate distributions of electrons in space can be obtained from diffraction and scattering experiments. In the original definition of quantum crystallography (QCr) given by Massa, Karle and Huang, direct extraction of wavefunctions or density matrices from measured intensities of reflections or, conversely, ad hoc quantum mechanical calculations to enhance the accuracy of the crystallographic refinement are implicated. Nevertheless, many other active and emerging research areas involving quantum mechanics and scattering experiments are not covered by the original definition although they enable to observe and explain quantum phenomena as accurately and successfully as the original strategies. Therefore, we give an overview over current research that is related to a broader notion of QCr, and discuss options how QCr can evolve to become a complete and independent domain of natural sciences. The goal of this paper is to initiate discussions around QCr, but not to find a final definition of the field.

  • Open Access English
    Authors: 
    Andreea Manole; Stephanie Efthymiou; Emer O'Connor; Marisa I. Mendes; Matthew J. Jennings; Reza Maroofian; Indran Davagnanam; Kshitij Mankad; Maria Rodriguez Lopez; Vincenzo Salpietro; +82 more
    Publisher: Elsevier
    Countries: France, Netherlands, Turkey
    Project: WT | Exploring novel molecular... (109915), UKRI | MRC Centre for Neuromuscu... (G0601943), ANR | UNISTRA (ANR-10-IDEX-0002), WT | Strengthening the neuromu... (201064), EC | REVERSIBLECOX (309548), EC | HUCNC (249968)

    Aminoacyl-tRNA synthetases (ARSs) are ubiquitous, ancient enzymes that charge amino acids to cognate tRNA molecules, the essential first step of protein translation. Here, we describe 32 individuals from 21 families, presenting with microcephaly, neurodevelopmental delay, seizures, peripheral neuropathy, and ataxia, with de novo heterozygous and bi-allelic mutations in asparaginyl-tRNA synthetase (NARS1). We demonstrate a reduction in NARS1 mRNA expression as well as in NARS1 enzyme levels and activity in both individual fibroblasts and induced neural progenitor cells (iNPCs). Molecular modeling of the recessive c.1633C>T (p.Arg545Cys) variant shows weaker spatial positioning and tRNA selectivity. We conclude that de novo and bi-allelic mutations in NARS1 are a significant cause of neurodevelopmental disease, where the mechanism for de novo variants could be toxic gain-of-function and for recessive variants, partial loss-of-function.

  • Open Access English
    Authors: 
    Wilfried Thuiller; Dominique Gravel; Gentile Francesco Ficetola; Sébastien Lavergne; Tamara Münkemüller; Laura J. Pollock; Niklaus E. Zimmermann; Florent Mazel;
    Publisher: HAL CCSD
    Country: France
    Project: ANR | FutureWeb (ANR-18-EBI4-0009), SNSF | FutureWeb (184131)

    International audience; Aim: The positive effect of primary productivity on animal species richness is one of the most conspicuous ecological features on Earth. However, less is known about the relationship between ecosystems primary productivity and the evolutionary history of biota. Here, we analyse how global primary productivity relates to the phylogenetic structure of vertebrate assemblages, and to the distribution of the most distinct lineages and recently diversified clades.Location: Global.Taxon: Amphibians, birds and mammals.Methods: We calculated relative phylogenetic diversity (i.e. phylogenetic diversity corrected for species richness), standardized effect size of the richness of top 25% evolutionary distinct species and of top 25% species‐level lineage diversification rates. We related these three metrics to mean net primary productivity (NPP) at the global scale, and for each zoogeographic region. We also tested the influence of the spatial scaling of species pool on the overall analyses (global, hemispheric and zoogeographic regions‐based species pools).Results: Phylogenetic diversity (corrected for species richness) of the three taxa decreases with NPP (in contrast with species richness) and varies considerably in space. High productivity sites harbour more closely related species than low productivity sites consistently across zoogeographic zones. However, the phylogenetically most distinct species are also found in high productivity sites, while the top most rapidly diversifying lineages are found in the least productive sites. Modifying the spatial extent of the species pool did not affect the results much.Conclusions: Benign conditions in high productivity sites (a) result in denser niche packing and thus allow for the coexistence of many closely‐related species and (b) protect the persistence of evolutionary distinct species. Low productivity sites may harbour fewer, more distinct and temporarily more variable niches that allow maintenance of unique lineages for longer periods of time.