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Ashes to art: The glassmaking traditions of Königsfelden’s medieval windows
No full textInternational audienceThe chemical composition and optical properties of the stained-glass windows in the Königsfelden Abbey church (Aargau, Switzerland), which are among the oldest and best-preserved examples from the 14th century in the region, were analysed on site using portable X-ray fluorescence (pXRF) and optical absorption spectroscopy. A subset of loose fragments was further characterised by Raman spectroscopy and LA-ICP-MS, and these data were used to improve the calibration of the results obtained with in situ pXRF. A machine-learning classifier (GLORIA) was applied to assess the variability of the glasses and their provenance relative to a reference database of European stained-glass windows. The results demonstrate that the Königsfelden corpus consists of potash-based forest glasses, mostly attributed to Central Europe (59%), with additional inputs from the Rhine region (32%) and Northwestern France (9%). While the colouring mechanisms for cobalt blue, copper red, manganese purple, silver yellow and iron sulphide amber are relatively well understood, the colouring techniques of a distinctive bluish grey and rare Pb-rich green glass ( ∼10 wt% PbO) are unusual and have no clear published parallels. One hypothesis for the high PbO contents in green glass is that a CuO-PbO frit was deliberately employed to facilitate the dissolution of metallic copper in the silicate melt. The blue-grey glass, unique in hue and composition, appears to result from the combination of a manganese-cobalt glass with an additional, yet unidentified, contribution. Our study thus provides new insights into medieval glass recipes, trade networks, and workshop practices, while also validating the potential of calibrated pXRF combined with reference standards and machine learning for heritage science applications
Tropical salinity contrast strengthening in CMIP6: inter-model diversity and mechanisms
No full text\ₑprint: https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2025EF007346International audienceWe analyze projected tropical sea surface salinity (SSS) changes in 32 CMIP6 models' historical and SSP5-8.5 scenario simulations, examining both the multi-model mean (MMM) and inter-model diversity. By 2100, MMM inter-basin contrasts strengthen, with freshening in the tropical Indian Ocean (TIO) and equatorial-northern Pacific (ENPO), and saltening in the southern Pacific (SPO) and tropical Atlantic (TAO). Basin-scale future SSS changes are primarily driven by surface freshwater fluxes, with lateral advection redistributing anomalies within each basin. Precipitation dominates the freshwater flux changes, except in the tropical Atlantic where evaporation plays a key role. Two uncorrelated indices, contrasting SPO versus TIO and TAO versus ENPO, explain 76% of the variance across models. Physically, stronger relative warming of the Northern Hemisphere enhances rainfall over the TIO monsoon region (freshening) while suppressing rainfall along the South Pacific Convergence Zone (saltening). The increasing TAO–ENPO contrast arises from two distinct mechanisms: in the Pacific, an enhanced El Niño–like warming pattern reduces atmospheric stability, intensifying rainfall and freshening ENPO; in the Atlantic, saltening reflects stronger evaporation under warmer conditions, though at a weaker rate than predicted by Clausius–Clapeyron scaling ( \\vphantom\\\sim \\4.2 vs. \\vphantom\\\sim \\7% \\vphantom\\\mathrmK^-1\\). Previous studies linked strengthening of inter-basin salinity gradients to a thermodynamically intensified hydrological cycle. Our analysis highlights a more nuanced picture: Atlantic saltening reflects this thermodynamic control, while SSS changes elsewhere are mainly driven by atmospheric circulation and rainfall changes tied to uneven SST warming. The CMIP6 statistical analyses highlight dynamical mechanisms that motivate further testing through targeted ocean simulations
Media Review: One Battle after Another, The Past as a Safe House, and the Afterlives of Clandestine Organizing
No full textInternational audienceIn the United States, political violence circulates as a floating signifier invoked to harden policing, to delegitimize protest, and to sustain an anxious public dramaturgy.Many film critics have framed One Battle After Another, released worldwide in September 2025, as a political film that meets the moment head-on. Yet its most generative move lies elsewhere. Freely adapting Thomas Pynchon's Vineland (1990), the film treats revolution less as a program than as memory-work: clandestinity replayed like a beloved record, in the shelter of safe houses and code words, while the present stubbornly mutates its surveillance, its rhetorics, and its enemies. Read through an organizational lens, the film becomes less a manifesto than an inquiry into how underground collectives persist in the rear-view mirror: how secrecy is maintained, how partial organizations cohere, and how violence is organized, sensed, and survived. If the film feels timely, it is also because it insists on being out of sync: its politics is filtered through the afterlives of older struggles. The underground it depicts does not merely hide from the present; it shelters inside a past that keeps replaying itself.One Battle After Another compresses, at first, the story of a militant couple inside a farleft faction called the "French 75". Pat Calhoun (an anagrammatic wink to the director's initials "PTA") is played by Leonardo DiCaprio; his lover and comrade, Perfidia Beverly Hills, is played by Teyana Taylor.</p
Geometry of Sparsity-Inducing Norms
No full textInternational audienceSparse optimization seeks an optimal solution with few nonzero entries. To achieve this, it is common to add to the criterion a penalty term proportional to the -norm, which is recognized as the archetype of sparsity-inducing norms. In this approach, the number of nonzero entries is not controlled a priori. By contrast, in this paper, our motivation is to find an optimal solution with at most~ nonzero coordinates (or for short, -sparse vectors), where is a given sparsity threshold (or ``sparsity budget''). For this purpose, we study the class of generalized -support dual~norms that arise from any given so-called source norm. When added as a penalty term, we provide conditions under which such generalized -support dual~norms promote -sparse solutions. The result follows from an analysis of the exposed faces of closed convex sets generated by -sparse vectors, and of how primal support identification can be deduced from dual information. Finally, we study some of the geometric properties of the unit balls for the -support dual~norms and their dual norms when the source norm belongs to the family of -norms. In particular, we show a striking structural property: every proper face of the unit balls for the -support dual~norms is a hypersimplex, i.e., the convex hull of -valued points with the same \lzero-norm
AVO-QP: Task-Adaptive Real-Time Obstacle Avoidance for Redundant Manipulators on Edge Platforms
No full textInternational audienceWe address real-time obstacle avoidance for redundant manipulators where tracking and safety constraints can conflict and render quadratic programs (QPs) infeasible. We propose AVO-QP, a sensor-guided velocity-level planner that fuses RGB-D depth with learned detection to maintain situational awareness, and executes the full perception–planning–control loop on edge platforms without centralized servers. A task-adaptive avoidance vector Uavo modifies the translational tracking constraint when obstacles enter a safety margin, reducing tracking–avoidance conflicts while preserving QP feasibility. A dual-objective cost balances joint-velocity magnitude and inter-step variation, and a projected primal–dual RNN solves the QP at control rate to produce smooth, feasible joint commands. Experiments on a 7-DOF Franka Panda (simulation) and a 6-DOF UR5 (hardware) with static and dynamic obstacles show an overall success rate of 84.09%, average planning times of 19.0–20.3 ms on edge devices, and terminal position errors down to 0.0001 m in static scenes while respecting distance constraints. These results suggest that AVO-QP enables responsive manipulation in cluttered workcells under tight latency budgets
Relativistic Feedback Discharges in Dielectric Solids
No full textInternational audienceThe photoelectric feedback processes leading to growth of relativistic runaway electron avalanches are believed to be responsible for extreme uxes of gamma rays produced from very compact regions of space with dimensions on the order of hundred meters in association with lightning activity in the Earths natural environment (Pasko et al., 2025, https://doi.org/10.1029/2025JD043897). Here we demonstrate for the rst time that the same photoelectric feedback discharges can be realized on centimeter scales in common solid state dielectric materials, like quartz, acrylic and bismuth germanate. These discharge can serve as new sources of high energy X-ray radiation
Temporal motif-based representation learning on continuous-time dynamic graphs
No full textInternational audienc
Concurrent heat waves and their linkage to large-scale meridional heat transports through planetary-scale waves
No full textInternational audienceWe investigate concurrent heatwaves across the Northern Hemisphere through the linkage between extremes in Meridional Heat Transport (MHT) and in hemispheric land surface temperature (LST). MHT provides fundamental insight on how large-scale thermodynamics links to atmospheric large-scale dynamics, especially through the action of the eddy planetary-scale circulation in the mid-latitudes. The phase and amplitude of these waves can in fact favor the simultaneous occurrence of heatwaves in remote regions, but how this relates to the amount of heat carried by them has not yet been discussed. In this work, we find that the conditional occurrence of extremely weak MHT and extremely warm hemispheric LSTs is significantly more frequent than other conditional occurrences, both in Summer (JJA) and in Winter (DJF). We argue that the combination of extremely weak, in some cases equatorward, MHTs and warm LSTs in JJA are associated with the reversal of the MHT contribution by zonal wavenumber 3, which is in turn associated with the frequency of atmospheric blocking in western Eurasia and the intensity of blockings and jet stream over the Northwestern Pacific. In DJF, the weak, albeit never equatorward, MHT – warm LST events are characterized by a suppression of the climatologically dominant wavenumber 2, which weakens the overall MHT. The flow is anomalously zonal across much of North America and Eurasia, with reduced frequency of atmospheric blockings and downstream displacement of the jet stream, advecting moist and mild air eastward into the continents. Overall, such dynamical pattern correspond to abnormally warm and widespread temperatures in North America, Eastern Europe, and China. The conditional occurrence of extremely weak MHTs and warm hemispheric LSTs is found to be related to between 30 % and over 40 % of extremely warm hemispheric LST days in both seasons
How I Met Your Snowclone: Unsupervised Discovery of Snowclone Patterns in Large Datasets
No full textInternational audienceSnowclones are a type of Multiword Expression (MWE) pattern that includes open slots, i.e. positions that can be filled with various words. For example, in the phrase "May the X be with you," the slot X can be replaced with virtually any noun. A key feature of snowclones is that the original MWE remains recognizable, carrying its meaning into the new form. However, previous work has not shown whether such substitutions are limited to fixed positions. In practice, variations such as "May the force \textbf{bee} with you" are also possible. In this paper, we propose to use Locality Sensitive Hashing (LSH) to automatically extract snowclone patterns from the non-commercial IMDb dataset. This process results in the creation of the \textsc{FROST} lexicon, comprising 30,826 pattern candidates and 1,059,824 snowclone candidates distributed in 30 languages. We then annotate 1,500 discovered patterns and 1,000 snowclones from the \textsc{FROST} lexicon to assess its quality. Our findings suggest that (i) most substitutions in snowclones occur at consistent positions and (ii) snowclones can be reliably discovered at scale using LSH and similarity-based metrics. This work provides the first large-scale lexicon of snowclone-based MWEs and a method that can support future research on MWEs and snowclones discovery
