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Auto-LSN: fully automated liver surface nodularity quantification in CT based on deep learning for the evaluation of advanced chronic liver disease
No full textInternational audienceAbstract Objective This study evaluated the applicability and performance of the SDR4MR method at 1.5 T and 3 T across different acquisition scenarios in a clinical environment. Materials and methods The SDR4MR hardware consists of a broadband receiver coil connected to a software-defined radio (SDR) via optional RF attenuators. The SDR stick is plugged into the computer's USB port, which runs the SDR software and a Mathematica script to decode the RF pulse sequence. Several MRI pulse sequences were recorded: (i) a multi-echo multi-slice spin echo sequence to check the SDR4MR configuration on a well-known simple sequence; (ii) 2D and 3D sequences for which detailed information is not available in the user interface. Results The measured RF pulse sequences have been drawn in the style of illustrations found in MRI textbooks. Sequence times and amplitudes were estimated, and sequence details not described in the MRI user interface were retrieved. Conclusion The present study demonstrated the implementation of SDR4MR on clinical scanners. This easy-to-use configuration enables precise monitoring of RF pulse sequences. This method could be further improved by taking advantage of advances in SDR hardware and software
Oceanic δ<sup>13</sup> C Fingerprints Caused by Laurentice Ice Sheet Discharges: Model‐Data Comparison During Heinrich Event 4
No full textInternational audienceAbstract This study investigates the sensitivity of the oceanic circulation and of the dissolved inorganic carbon to ice discharge events from the Laurentide ice sheet (LIS), using an isotope‐enabled and coupled climate–ice sheet model, and observations. The ice discharges are triggered by either reduced friction at the ice sheet‐bedrock interface or increased oceanic melt rates in the Hudson Strait ice stream region. The simulated decreases in both scenarios, following freshwater release and the weakening of the Atlantic Meridional Overturning Circulation. The best agreement with the observed anomalies is achieved with large ice volume loss, by reducing ice sheet basal friction. In our model, the freshwater discharges from the LIS need to be amplified to better represent the observed changes. The LIS alone does not seem able to explain the observed oceanic variations, which may indicate that additional processes are required to account for these changes
Jëfandikoo model ngir seetlu tukki yi ñeel nappum Senegal bu artisanal bi
No full textThe North-West African coast is enriched by the Canary current, which sustain a very produc- tive marine ecosystem. The Senegalese artisanal fishing fleet, the largest in West Africa, ben- efit from this particularly productive ecosystem. It has survived the ages with remarkable adaptability, and has great flexibility allowing it to react quickly to changes, in particular by changing fishing gear and performing migrations. However, since the 1980s, the increasing fishing effort led to a progressive fish depletion, increasing fisher’s migration distances to access new fishing grounds. Since 2007 many fishers even started to navigate to Canary archi- pelago in order to find a more lucrative job in Europe, carrying candidate to emigration in their canoes. This phenomenon further increased since 2022 due to a new drop in fishery yields, consecutive to the development of fishmeal factories along the coast that amplified overfishing. Climate change may also impact fish habitat, and by consequence the distribution of fishing grounds. The question addressed in this research was how climate change, fishing effort and socio-economic parameters interact and determine the artisanal fishery dynamics. An interdisciplinary approach allowed us to collect data and qualitative information on cli- mate, fishing effort and socio-economic parameters. This served as a basis to build a multi- agent model of the mobility of Senegalese artisanal fishing. We implemented a first version of the model and presented some preliminary simulations with contrasted fishing effort and climate scenario. The results suggested that first, climate change should have only a slight impact on artisanal fishing, even in the most extreme climate scenario considered. Second, if fishing effort was maintained at current levels, we found a collapse of the fishery with massive fishers migrations whatever the climate scenario. Third, with reduced fishing effort, a sustain- able fishery equilibrium emerges in which Senegal's artisanal fishery catches ~250,000 tons of fish a year mostly in Senegal, approaching the 2000s catches records. This sustainable equi- librium maintained with the two-climate change scenario tested. Fishers migrations provide clues of the fish populations state and have implications for the sustainable exploitation of fishing resources. Senegalese artisanal fishers’ migrations impact the regional distribution of the fishing effort, therefore must be taken into account in regional development and planning policies for this sector, particularly in a context of increasing infrastructure and spatial man- agement measures (e.g. marine protected areas). This work lays the foundations of a computer simulation tool for decision support.La flotte de pêche artisanale sénégalaise, composée de près de 20 000 pirogues, est la plus importante d’Afrique de l’Ouest. Elle a traversé les époques avec une remarquable adaptabilité, et possède une grande souplesse lui permettant de réagir rapidement aux changements, notamment par le changement des engins de pêche et par la mobilité à l’échelle sous régionale. Les dynamiques d’auto-organisation de ce secteur ont fait l’objet de nombreuses études qui visent à soutenir la cogestion. La mobilité de l’effort de pêche a des implications sur l’exploitation durable des ressources halieutique, et est donc un aspect à prendre en compte dans les politiques de développement et d’aménagement de ce secteur, notamment dans un contexte de multiplication des infrastructures et des mesures de gestions spatiales (e.g. aires marines protégées). Ici nous proposons une description détaillée d’un modèle multi-agent de la mobilité de la pêche artisanale sénégalaise. Nous tentons de positionner le modèle à un niveau de complexité intermédiaire, en synthétisant les éléments présents dans la littérature pour décrire une image simplifiée de la flotte de pêche artisanale. Ce travail jette ainsi les bases d’un outil informatique de simulation pour l’aide à la décision. Nous avons mis en œuvre une première version du modèle et présenté quelques simulations préliminaires avec des scénarios contrastés en matière d'effort de pêche et de climat. Les résultats suggèrent un impact modéré du changement climatique ne devrait avoir qu'un impact limité sur la pêche artisanale, du fait de la forte mobilité de celle-ci. Deuxièmement, si l'effort de pêche était maintenu à son niveau actuel, le modèle suggère un effondrement de la pêche accompagné d'une migration massive des pêcheurs, quel que soit le scénario climatique. Troisièmement, avec un effort de pêche réduit, un équilibre durable de la pêche émerge du model, dans lequel la pêche artisanale sénégalaise capture environ 250 000 tonnes de poissons par an, principalement au Sénégal, ce qui se rapproche des niveaux de captures des années 2000. Cet équilibre durable se maintient avec les deux scénarios de changement climatique testés. Les migrations des pêcheurs fournissent des indices sur l'état des populations de poissons et impactent la répartition régionale de l'effort de pêche. Ces migrations devraient donc être prises en compte dans les politiques régionales de développement et de planification de ce secteur, en particulier dans un contexte de renforcement des infrastructures et des mesures de gestion spatiale (par exemple, les aires marines protégées). Ce travail jette les bases d'un outil de simulation informatique pour l'aide à la décision
Sputtered species during ion irradiation of adenine: Implications for Titan's atmospheric chemistry
No full textCassini-Huygens detected complex molecules exceeding several thousand atomic mass units in Titan's atmosphere as well as energetic O+, OH+ and H2O+ ions in Saturn's magnetosphere. The heavy molecules are suggested to be nitrogenous polycyclic aromatic hydrocarbons (PANH). The energetic ions are thought to penetrate into Titan's atmosphere, potentially modifying the structure and chemistry of these macromolecules. This study investigates the composition of chemical species sputtered into the gas-phase once energetic ions impact said macromolecules. We have irradiated thin film samples of adenine (C5H5N5), a heterocyclic aromatic, at the HUN-REN Institute for Nuclear Research (ATOMKI) in Debrecen, Hungary. The experiments varied key parameters such as ion type (Neq+, Oq+, OHq+ and H2Oq+), energies (10 and 20 keV), temperatures (150 and 300 K) and fluences (up to 2 × 1015 ions . cm-2). In-situ quadrupole mass spectrometry measured the residual gas of the experimental chamber, analysing the material that was sputtered into the gas phase during irradiation. The deconvolution of these mass spectra was done using a Monte-Carlo approach, revealing a plethora of compounds including HCN, N2, C2N2, C2H3N, C3HN, CH2N2, NH3, C2H2 and CH4. Larger species like C5H5N5, C4H4N4 and C3H3N3 were only detected at the on-set of the irradiation. The sputtering of hydrocarbons and nitriles highlights a potential feedback mechanism in Titan's atmosphere. The direct formation of CO and CO2 from PANH irradiation appears unlikely
Long-lived Left-Right signals at the FCC-ee
No full textInternational audienceWe give an extensive discussion of the displaced signals of heavy Majorana neutrino production at future electron-positron colliders operating at various proposed energies in the context of the Left-Right symmetric model. A comprehensive collection of channels is taken into account, ranging from those featuring and mediation to those induced by scalar mixing and gauge/scalar boson fusion, with connections to the mechanism of neutrino mass origin. The emerging signatures feature possibly multiple displaced heavy neutrinos that are in some cases accompanied by prompt activity and forward leptons. We derive the corresponding total production rates and differential distributions, which allow us to differentiate the channels and have analytical estimates of the signal yield. We then develop realistic estimates of the selection efficiencies using a dedicated vertexing algorithm which establishes the displaced decay positions and supplies a reliable proxy for reconstructing the full four-momenta of long-lived particles. This allows to determine the realistic reaches in the parameter space of the Left-Right symmetric model across the various channels, and we show that these can strongly surpass the LHC ones, demonstrating that future lepton colliders are sensitive to left-right symmetry breaking scales in the deep multi-TeV regime
Seeing in the dark: Towards a broad construction of the access to data provisions of the DSA
No full textInternational audienceThe Digital Services Act (DSA) is the most ambitious effort taken by liberal democratic nations to regulate social media platforms. One of the main ways it does this is by establishing various transparency obligations applicable to all platforms and search engines, as well as a specific transparency and data-sharing regime for the largest platforms and search engines, defined by the number of users. Specifically, Article 40 of the DSA grants vetted researchers access to data "for the sole purpose of conducting research that contributes to the detection, identification and understanding of systemic risks in the Union. " This article argues that Article 40's requirement for the requested data to be "necessary and proportionate" to conduct a specific type of research may hinder effective research. Indeed, researchers have been denied broad access -or any access to data -on privacy or confidentiality grounds before (Bontcheva, 2024). Consequently, researchers have limited prior knowledge of social media impacts and thus may have limited knowledge about what data, exactly, they need. Drawing on cutting-edge social media research, we explain why vetted researchers may thus need broad access to social media data to meet the objectives of the DSA. More specifically, we argue that researchers need access to system-level data, meaning data that captures how an entire digital system or platform operates, not just the activity of individual users. Consequently, we propose an interpretation of the DSA's data request requirements that would enable researchers to study the online political landscape of EU member states effectively
Temporal evolution and origin of radionuclide fallout and contaminants recorded in sediment from the Kerguelen Archipelago fjord system
No full textInternational audienceDeposition of heavy metals and persistent organic pollutants (POPs) to fjord systems during ice melting was investigated with a sediment core collected in Table Fjord from Kerguelen Island (49° 33.8 S-69° 13.9 E) situated in the Southern Indian Ocean. Multiple radionuclides ( 210 Pbex, 137 Cs, 240 Pu/ 239 Pu) were used to establish an accurate age-depth model and show the occurrence of French nuclear weapon test fallout in this remote region for the first time. Environmental changes related to the retreat of the Cook Ice Cap since the 1960s were found to be one of the major factors dominating the dynamics of anthropogenic lead deposition flux in the fjord through the release of long-range transported legacy anthropogenic lead. The released legacy anthropogenic lead was likely transported across the proglacial Ampere Lake by a hypopycnal plume to the fjord. Backward trajectories and lead stable isotopic signatures suggest the southern part of South Africa as a major source of anthropogenic lead transported to Kerguelen Archipelago. In contrast, contamination by arsenic, molybdenum, antimony and POPs was found to be more recent (since 2001). Fractionation of rare earth elements was observed in the sediment due to the formation of proglacial Ampere Lake, which acts as a sediment trap
Association between in utero exposure to acetaminophen and external genital tract malformations in boys and girls: a systematic review and meta-analysis
No full textInternational audienceSTUDY QUESTION: Is the use of acetaminophen during pregnancy associated with external genital tract malformations in boys and girls? SUMMARY ANSWER: This meta-analysis found no evidence linking in utero acetaminophen exposure to external genital malformations in boys but further research focusing on girls and considering relevant confounding factors is needed. WHAT IS KNOWN ALREADY: Acetaminophen is widely used by pregnant women, but findings are conflicting regarding a possible increased risk of genital malformations in the offspring of both sexes. STUDY DESIGN, SIZE, DURATION: In this systematic review and meta-analysis, we searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, International Clinical Trials Registry Platform, ClinicalTrials.gov on 18 April 2024, and subsequently updated the search on 20 September 2025 for randomized controlled trials and observational studies. This meta-analysis included randomized controlled trials and observational studies focusing on the association between in utero exposure to acetaminophen, with no restriction on publication dates and languages. PARTICIPANTS/MATERIALS, SETTING, METHODS: Two reviewers independently screened studies, extracted data, and assessed risk of bias. The two primary outcomes were a composite endpoint including cryptorchidism, hypospadias, and penile hypoplasia in boys, and a composite outcome including clitoral enlargement, labial fusion, vulvar malformations, and rectovaginal fistula in girls. Secondary outcomes included individual genital malformations and differences in anogenital distance (AGD). GRADE was used to evaluate the level of certainty. MAIN RESULTS AND THE ROLE OF CHANCE: Ten observational studies were included. Regarding boys, meta-analysis of the predefined primary outcome could not be performed as no studies reported penile hypoplasia. Another composite endpoint including cryptorchidism and/or hypospadias was reconstructed and no significant association was found with acetaminophen, pooled crude odds ratio (OR) 1.27 [95% CI (0.18, 8.94), studies = 2, participants = 155 362, I2=79%, phet=0.03, random-effects model (REM)]. No significant association was found for cryptorchidism or hypospadias separately based on adjusted estimates with pooled OR of 1.02 [95% CI (0.78, 1.35), studies = 3, participants = 155 852, I2=32%, phet=0.23, REM] and 1.02 [95% CI (0.89, 1.17), studies = 3, participants = 159 572, I2=40%, phet=0.19, REM], respectively. No significant difference was found for short AGD. No meta-analysis was possible for girls for any of the predefined outcomes due to lack of data. The level of certainty was low to very low. LIMITATIONS, REASONS FOR CAUTION: The predefined primary outcomes in boys and girls could not be fully evaluated. Small study effects could not be assessed as the number of included studies was limited. There was significant heterogeneity in the reporting of results and information regarding maternal characteristics was lacking. Lastly, all included studies had a serious or critical risk of bias due to the limited control of confounding factors and the level of certainty was low to very low. WIDER IMPLICATIONS OF THE FINDINGS: Acetaminophen remains an indispensable medication and abstaining from pain and fever treatment during pregnancy may have harmful effects on the developing fetus. Further research on external genital malformation risks following in utero exposure to acetaminophen should be directed toward developing validated and robust drug-exposure and outcome assessment tools, that control for confounding factors and confounding by indication. STUDY FUNDING/COMPETING INTEREST(S): No funding was used to conduct this study. No relationship or activity could appear to have influenced the submitted work
Dry electrode architecture design to push energy density limits at the cell level
No full textInternational audienceHigh-energy lithium batteries require electrode architectures that enable high areal capacity, high active material content, and stable high-voltage operation—requirements that conventional slurry-based electrodes struggle to meet due to inefficient electron percolation, parasitic reactions, and limited processing-architecture predictability. Here we design and validate a dry-processed electrode architecture that leverages molecular-level coupling between fibrous carbon and binder to promote efficient electronic conduction while suppressing high-voltage interfacial degradation. This architecture achieves areal loadings >5 mAh cm−2 with >99 wt% active material and supports stable operation up to 4.70 V without compromising rate capability. The 4.55 V NMC811||graphite pouch cells retain 78% capacity after 1,000 cycles at C/3-rate, with average Coulombic efficiency exceeding 99.9%. These results are achieved without material-level modifications or specialized electrolyte additives, highlighting the potential of electrode engineering alone to unlock the intrinsic performance of active materials even under demanding conditions of high areal loading and maximum active material content