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Tectonic accommodation of the northern Antilles strike slip to subduction transition along the Porto-Rico – Anegada – Lesser Antilles Margin
No full textInternational audiencePlate motion along concave (toward the upper plate) strike slip to subduction transition (SSST) where the down going plate does not tear, results over time in a lengthening of the subduction zone while the downgoing plate is transported along the transform margin. In the northern Antilles such a transition has developed since the late Paleogene while the Bahamas bank swept the northern Antilles margin and collided with Hispaniola westward. Tectonic record along the Puerto-Rico (PR), Anegada and the northern Lesser Antilles (NLA) margin reveals the modalities of the SSST evolution and gives insights into the interaction between the subducting North America oceanic plate and the overriding Caribbean plate.We present a detailed structural map from eastern PR to southern Anguilla platform in the Lesser Antilles based on interpretation of multibeam bathymetry and multichannel seismic data.We confirm that plate motion partitioning between a trench parallel strike slip fault and thrusting along the interplate is exclusively restricted to the margin tip east of the Bunce Fault. Further upslope, the Virgin Islands northern margin is affected by trench-parallel, trenchward dipping normal faults. These faults accommodate the deepening of the margin interpreted as the result of basal tectonic erosion. From NLA westward to St Croix and southern Virgin Islands, the margin is dislocated by a cross cutting pattern of NE-SW and E-W normal fault systems, bounding elongated E-W throughs, rhomboidal basins and S-shaped ridges. Formally interpreted as either slip sense strike-slip system along the Anegada Passage, the structural pattern that we describe, supported by our seismic interpretation, reveals limited left lateral displacement restricted to the EW basins. Instead, the cross fault system appears to accommodate NW-SE extensional tectonics. At a regional scale along the SSST, from the Lesser Antilles margin to Hispaniola collision zone, the strain pattern along the margin progressively evolves from NNW-SSE extension responsible for V-shaped basins open toward the trench, to NW-SE extension along the Anegada passage and increasing shortening along the Muertos through from Southeastern Puerto Rico westward. Such a pattern attests for a progressive bending of the margin in a context of low interplate coupling along the evolving SSST
Dust emission from the bulk of galaxies in the Epoch of Reionisation
No full textInternational audienceThe excess of UV-bright galaxies observed at z > 10 has been one of the major surprises of the early JWST observations. Several explanations have been proposed to understand the mild change in space density of the UV-bright galaxies at these high redshifts, among them an evolution of dust attenuation properties in galaxies. However, our view of dust in primordial galaxies is limited towards a few tens of z ∼ 7 galaxies, pre-selected from UV-optical observations, and are thus not necessarily representative of the bulk of the sources at these redshifts. In this work, we aim to constrain the dust properties of galaxies at 6 < z < 12 by making the most of the A 3 COSMOS database in the JADES/GOODS-South field. We stacked ALMA band 6 and 7 observations of 4464 JADES galaxies covered by the A 3 COSMOS database and used the measurements as constraints to perform UV-to-FIR SED modelling. We obtained tentative signals for the brightest UV galaxies (M UV < -19 mag) as well as for the most massive ones (log M /M > 9) at 6 < z < 7, and upper limits for fainter (M UV > -19 mag), lower-mass sources (log M /M < 9), or ones at higher redshift (z > 7). Fitting these 6 < z < 7 galaxies with ALMA constraints results in lower star formation rates (-0.4 dex) and FUV attenuation (-0.5 mag) for galaxies with log M /M > 8, compared to the fit without FIR. We extend the L IR vs M UV relation down to M UV = -19 mag and show a tentative breakdown of the relation at fainter UV magnitudes. The positions of the JADES z ∼ 6.5 sample on the infrared excess (IRX) versus β and IRX versus M diagrams are consistent with the ones of the ALPINE (z ∼ 5.5) and REBELS (z ∼ 6.5) samples, suggesting that the dust composition and content of our mass-selected sample are similar to the ones of these UV-selected galaxies. Extending our analysis of the infrared properties to z > 7 galaxies, we find a non-evolution of β in the M UV range probed by our sample (-17.24 +0.54 -0.62 ), and highlight the fact that samples from the literature are not representative of the bulk of galaxy populations at z > 6. We confirm a linear relation between A V and sSFR -1 with a flatter slope than previously reported due to the use of ALMA constraints. Our results suggest that rapid and significant dust production has already happened by z ∼ 7.</div
Euclid preparation. LXXIV. Euclidised observations of Hubble Frontier Fields and CLASH galaxy clusters
No full textInternational audienceWe present HST2EUCLID, a novel Python code to generate Euclid realistic mock images in the , , , and photometric bands based on panchromatic Hubble Space Telescope observations. The software was used to create a simulated database of Euclid images for the 27 galaxy clusters observed during the Cluster Lensing And Supernova survey with Hubble (CLASH) and the Hubble Frontier Fields (HFF) program. Since the mock images were generated from real observations, they incorporate, by construction, all the complexity of the observed galaxy clusters. The simulated Euclid data of the galaxy cluster MACS J0416.12403 were then used to explore the possibility of developing strong lensing models based on the Euclid data. In this context, complementary photometric or spectroscopic follow-up campaigns are required to measure the redshifts of multiple images and cluster member galaxies. By Euclidising six parallel blank fields obtained during the HFF program, we provide an estimate of the number of galaxies detectable in Euclid images per per magnitude bin (number counts) and the distribution of the galaxy sizes. Finally, we present a preview of the Chandra Deep Field South that will be observed during the Euclid Deep Survey and two examples of galaxy-scale strong lensing systems residing in regions of the sky covered by the Euclid Wide Survey. The methodology developed in this work lends itself to several additional applications, as simulated Euclid fields based on HST (or JWST) imaging with extensive spectroscopic information can be used to validate the feasibility of legacy science cases or to train deep learning techniques in advance, thus preparing for a timely exploitation of the Euclid Survey data
Probing moire excitons in MoSe2/WSe2 heterobilayers by combined micro-photoluminescence and lateral force microscopy
No full text10 pages, 10 figure
Les Hospitaliers provençaux à Rhodes et Malte (XIVe-XVIIe siècles)
No full textInternational audienceThis article examines the long history of the Hospitallers belonging to the Langue de Provence who resided in Rhodes and then Malta. It first considers their numbers, in absolute terms and relative weight, based on previously unpublished data. Their numbers fluctuated between forty and one hundred knights. The knights' varied careers are examined, particularly their role on the Order's ships. There were also numerous local positions held by Provençals, who were reserved the posts of Grand Commander, Commander of Artillery, and Commissioner of Granaries, while the Grand Priors of Saint-Gilles and Toulouse, as well as the Bailiff of Manosque, often resided overseas. The Auberge de Provence is one of the most important buildings in Rhodes and Malta. However, many knights have their own homes, with some even enjoying a family residence in Valletta, a sign of their deep roots in the areaCet article étudie dans la longue durée les chevaliers de l’ordre de l’Hôpital faisant partie de la Langue de Provence et résidant à Rhodes puis à Malte. Il envisage d’abord leur nombre, en valeur absolue et en poids relatif, à partir de données inédites. L’effectif fluctue entre une quarantaine et une centaine de chevaliers. Les carrières très variées des chevaliers sont étudiées, notamment leur rôle sur les vaisseaux de l’Ordre. Il existe par ailleurs de nombreuses charges locales occupées par les Provençaux à qui sont réservés les postes de grand commandeur, de commandeur de l’artillerie, de commissaire des greniers, tandis que les grands prieurs de Saint-Gilles et de Toulouse, ainsi que le bailli de Manosque, résident souvent outremer. L’Auberge de Provence figure parmi les bâtiments importants de Rhodes et de Malte. Cependant beaucoup de chevaliers disposent de leur propre maison ; certains bénéficiant même d’une demeure familiale à La Valette, signe de leur enracinement
Adaptive Gene Expression Induced by a Combination of IL-1β and LPS in Primary Cultures of Mouse Astrocytes
No full textInternational audienceAstrocytes are vital cells within the central nervous system (CNS), as they perform a critical role in supporting neurons by providing nutrients, such as lactate for energy, and safeguarding them against the toxicity of excessive neurotransmitters, such as glutamate. This study investigates astrocyte adaptive mechanisms in response to chronic inflammation. The primary aim is to assess the long-term effects of an inflammation-induced environment using a combination of lipopolysaccharide (LPS) and interleukin-1β (IL-1β), on the expression of key genes involved in essential metabolic pathways for astrocyte function, including glutamate metabolism and clearance, lactate synthesis and transport, and glucose metabolism. We observed an upregulation of the glutamate transporter eaat2 (but not eaat1), leading to glutamate accumulation and altered glutamate-glutamine cycling, as well as increased glycolytic activity and lactate production/export via hexokinases (hk1 and hk2) and the mct4 lactate transporter. Interestingly, these mechanisms are reversible, indicating a precisely controlled adaptive system. This investigation facilitated the identification of the signaling pathways involved in astrocyte adaptive responses to stress. This will further guide our investigations towards the more complex domain of resistance and adaptation of CNS in pathophysiological conditions
Contextualizing Toxicity: An Annotation Framework for Unveiling Pragmatics in Conversations of Online Discussion Forums
No full textThe role of context has attracted increasing attention in research on toxicity detection. Interpreting toxic language remains a complex and multifaceted challenge, shaped by numerous linguistic, contextual, and social factors. However, current approaches often define "context" narrowly, focusing primarily on surface lexical cues such as hate lexicons, profanity markers, or sentiment polarity. These features, while useful, are insufficient to capture the interactional dynamics, user behaviors, and intentionality that shape such phenomena. To address this gap, this paper introduces a novel and systematic annotation framework, grounded in Speech Act Theory (Austin, 1962), aimed at deciphering the illocutionary and perlocutionary dimensions of conversation, which are unexplored in existing studies. We apply this framework to a new dataset of complete Reddit conversation threads, sampled to include discussions that turn toxic (124 conversations, 1990 messages). We evaluate the performance of GPT models (GPT-3, GPT-4, and GPT-5) on this challenging annotation task, providing insights into how large language models capture pragmatic and contextual dimensions of online toxicity
Determinants of return to performance and recovery time in elite alpine skiers after ACL surgery
No full textInternational audienceAbstract Purpose Return to performance (RTPerf) after anterior cruciate ligament (ACL) surgery remains difficult to predict in elite alpine skiers, as general criteria may not fully apply. This study aimed to identify determinants and the time needed to achieve RTPerf at the same competitive level. Methods A prospective cohort of 71 elite alpine skiers (mean age: 23.6 ± 5.2 years; height: 173.0 ± 7.8 cm; weight: 72.0 ± 12.1 kg) who underwent ACL surgery was analysed. Demographic and contextual variables, including sex, age, world ranking and type of injury, were collected. Isokinetic knee muscle strength was assessed six months postsurgery. RTPerf (YES/NO) and time to return were evaluated 2 years postoperatively using the International Ski and Snowboard Federation points system. Associations with categorical and quantitative variables were assessed using χ 2 and t ‐ or Mann–Whitney U tests. Variables with p < 0.2 were included in multivariable logistic regression. Predictors of return time were analysed using Cox regression and receiving operating characteristic (ROC) curves. Statistical significance was set at p < 0.05. Results Seventy‐nine percent of skiers returned to preinjury performance within 2 years. Primary ACL injury (vs. revision) (odds ratio [OR]: 6.6; 95% confidence interval [CI]: 1.85–23.6; p = 0.004) and isolated injury (vs. complex) (OR: 5.35; 95% CI: 1.39–20.48; p = 0.014) were significant predictors. Average return time was 348 ± 51.6 days. Greater relative knee extensor strength was associated with earlier return. Limb symmetry in knee extension at 60°/s predicted return within 1 year, while the hamstring‐to‐quadriceps functional ratio at 90°/s predicted later return (area under the curve [AUC]: 0.78; p < 0.01). Conclusions Primary and isolated ACL injuries were linked to higher RTPerf rates, while greater knee extensor isokinetic strength was associated with shorter time to RTPerf in elite alpine skiers. Level of Evidence Level II
AM4DSP: Argumentation Mining in Structured Decentralized Discussion Platforms for Deliberative Democracy
No full textInternational audienceArgument(ation) mining (AM) is the automated process of identification and extraction of argumentative structures in natural language. This field has seen rapid advancements, offering powerful tools to analyze and interpret complex and large discourse in diverse domains (political debates, medical reports, etc.). In this paper we introduce an AM-boosted version of BCause, a large-scale deliberation platform. The system enables the extraction and analysis of arguments from online discussions in the context of deliberative democracy, which aims to enhance the understanding and accessibility of structured argumentation in large-scale deliberation processes