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Reversible Strong Metal‐Support Interactions in Co/TiO 2 Catalysts Driven by CO 2
No full textInternational audienceStrong metal–support interactions can significantly influence catalytic performance. On titania supports, these interactions often involve the formation of a substoichiometric TiO X overlayer during high‐temperature reduction, which can be reversed by treatments under dioxygen. Under CO 2 hydrogenation conditions, where water is produced, complete removal of the TiO X overlayer has been reported, raising questions about its stability in the presence of a mild oxidant such as CO 2 . In this study, in situ and operando techniques were employed to examine the effect of varying conditions on both the titania overlayer and cobalt species in a Co/TiO 2 catalyst. After reduction at 350 °C, the overlayer consisted of stoichiometric anatase TiO 2 , while cobalt remained partially reduced. Exposure to CO 2 /H 2 at 220 °C enabled complete cobalt reduction without affecting the TiO 2 overlayer. In contrast, pure CO 2 at 220 °C caused overlayer removal and full cobalt oxidation. The impact of this CO 2 ‐mediated reversibility on CO 2 hydrogenation was also evaluated. Although steady‐state activity was largely unaffected, the transient regime showed substantial changes in selectivity and behavior. These results demonstrate that different treatments can strongly influence both the stability and reactivity of Co/TiO 2 catalysts, highlighting the importance of dynamic SMSI effects in CO 2 hydrogenation
Morpho-phonetic effects in <irr-> prefixed words in British and American English
No full textInternational audienceThis paper presents a large-scale study of the duration of the first two segments inwords beginning with the orthographic sequence (e.g., irrational, irremovable)using speech data from British English and American English. We investigate theeffects of several predictors encoding the extent to which these words are segmentableinto their constituent parts using a dataset of over 1,500 audio extracts. When usingcategorical predictors to code segmentability, we find effects that are consistent withthe literature: more segmentable words have longer segments in the prefix and at theprefix-base boundary. We also report mixed results regarding measures of frequencyas proxies of segmentability, in line with the available literature. We also report effectsof non-morphological factors: [ô] is overall longer in American English than in BritishEnglish, and we find longer [ô] durations for male speakers than for female speakers
Renormalization of bosonic quadratic Hamiltonians involving rank-one perturbations
No full textWe study the renormalization of a bosonic quadratic Hamiltonian with an ultraviolet divergence. The Hamiltonian is composed of the sum of a free part and the square of the smeared field operator. We explicitly diagonalize the Hamiltonian via Bogoliubov transformations, thus simplifying its definition as a self-adjoint operator. Depending on the field operator's smearing, we discuss different renormalizations, either of the energy alone, or the energy and coupling constant together
A novel glutathione transferase harboring an FMN redox cofactor
No full textInternational audienceGlutathione transferases (GSTs) constitute a widespread superfamily of multifunctional enzymes with roles in cellular detoxification and secondary metabolism. We report that the poorly characterized Iota‐class enzymes (GSTIs) are mainly found in photosynthetic prokaryotes and eukaryotes, excluding Spermatophyta, and in a few fungi of the order Chytridiomycota. GSTIs are distinguished from other GSTs by the presence of N‐ and C‐terminal extensions of unknown function flanking the central GST domain. Focusing on the GSTI enzyme (SynGSTI1) of the model cyanobacterium Synechocystis sp. PCC 6803 ( S.6803 ), we showed that recombinant SynGSTI1 protein purified from Escherichia coli and S.6803 exhibited thiol‐transferase and dehydroascorbate reductase activities consistent with the presence of a CPYC catalytic motif in its GST domain. SynGSTI1 was found to be monomeric and to exhibit a spectrophotometric signature between 300 and 500 nm, which was attributed to a flavin mononucleotide (FMN). The C‐terminal domain of SynGSTI1 contained a conserved PRDM/L motif involved in the binding of an FMN ligand and showed a structure similar to that of the α‐subunit of phycoerythrin components of the light‐harvesting antenna of some cyanobacteria, most red algae and some cryptophytes. The deletion of the SynGSTI1 encoding gene in S.6803 (i) caused a slight decrease in the photosynthetic pigment content without impairing growth in standard photoautotrophic conditions; (ii) increased sensitivity to moderate and high light intensities; (iii) reduced glutathione levels and consistently; (iv) decreased tolerance to oxidative and metal stresses triggered by H 2 O 2 , diamide and cobalt. Thus, SynGSTI1 defines a unique GST subclass with critical roles in redox homeostasis and stress tolerance
4MOST Cosmology Redshift Survey (CRS): Clustering properties of CRS BG and LRG target catalogues
No full textInternational audienceThe 4MOST Cosmology Redshift Survey (CRS) will obtain nearly 5.4 million spectroscopic redshifts over deg to map large-scale structure and enable measurements of baryon acoustic oscillations (BAOs), growth rates via redshift-space distortions, and cross-correlations with weak-lensing surveys. We validate the target selections, photometry, masking, systematics and redshift distributions of the CRS Bright Galaxy (BG) and Luminous Red Galaxy (LRG) target catalogues selected from DESI Legacy Surveys DR10.1 imaging. We measure the angular two-point correlation function, test masking strategies, and recover redshift distributions via cross-correlation with DESI DR1 spectroscopy. For BG, we adopt Legacy Survey \texttt{MASKBITS} that veto bright stars, SGA large galaxies, and globular clusters; for LRG, we pair these with an unWISE W1 artefact mask. These choices suppress small-scale excess power without imprinting large-scale modes. A Limber-scaling test across BG -band magnitude slices shows that, after applying the scaling, the curves collapse to a near-common power law over the fitted angular range, demonstrating photometric uniformity with depth and consistency between the North (NGC) and South (SGC) Galactic Caps. Cross-correlations with DESI spectroscopy recover the expected , with higher shot noise at the brightest magnitudes. For LRGs, angular clustering in photo- slices () is mutually consistent between the DECaLS and DES footprints at fixed and is well described by an approximate power law once photo- smearing is accounted for; halo-occupation fits yield results consistent with recent LRG studies. Together, these tests indicate that the masks and target selections yield uniform clustering statistics, supporting precision large-scale structure analyses with 4MOST CRS
Cultural Production Reveals Transitions to Sustained Human Development in both European and Non-European Societies
No full textSustained human development is often seen as a recent phenomenon, primarily linked to Europe's Industrial Revolution. This perspective has shaped much of our historical understanding, but it relies on a limited set of economic indicators with restricted temporal and geographic coverage. In this article, we introduce Cultural Production as a complementary proxy for human development, particularly suited to long-term and cross-regional comparisons. Cultural production reflects the extent to which societies enable individuals to acquire knowledge, develop skills, and contribute to intellectual and artistic life-conditions closely tied to education, health, material security, and institutional support. We construct a global dataset tracking 122,634 distinct cultural producers (e.g., scientists, artists, writers) and apply ecological methods to estimate the number of unrecorded figures, correcting for differential survivorship bias. The resulting measure enables a broader and deeper reconstruction of human development across time and space. Our results challenge the prevailing view that meaningful development began only in modern Europe. We confirm that Western Europe experienced continuous gains from the 11th century onward, but we also uncover sustained growth in non-Western regions long before the 19th century. Japan shows multiple developmental phases, including a continuous rise after 1500 CE. In China, we trace human development back over 1,500 years, identifying major advances during the Han, Tang, and late imperial periods. In South and West Asia, we reveal marked progress under the Abbasid Caliphate and the Delhi Sultanate. Cultural Production also enables estimates of human development for Antiquity, showing developmental peaks in Classical Greece and Rome, though these were not sustained. Altogether, our findings suggest that all major regions, including non-European societies, transitioned from stagnation to sustained growth well before the Industrial Revolution-some as early as 1000 CE. These results suggest a more widespread and earlier pattern of human development across civilizations than previously recognized
Very High Deposition Rate Additive Manufacturing for Low Alloy Steel Parts : Ductility and Eligibility for Critical Applications
No full textInternational audienc
The Caravan Roads and Way Stations in North-West Arabia (CaRoWS) Project. Report on the 2025 Season.
No full textThis is the report of the 2025 fieldwork season undertaken by the CaRoWS project in the Saudi Arabian Ḥismā. It contains several chapters : on the Greek, Early Islamic, Ancient North Arabian and Nabataean as well Developing Arabic inscriptions. They are preceded by an introduction and followed by a general commentary. It contains also appendices, among which maps, a list of sites and a catalogue of the new Nabataean and Nabataeo-Arabic inscriptions. 33 plates illustrate the report.Ceci est le rapport de la campagne 2025 du projet CaRoWS dans la Ḥismā saoudienne. Il comprend plusieurs chapitres consacrés aux inscriptions grecques, arabes, nord-arabiques anciennes, nabatéennes et nabatéo-arabes. Il comprend également une introduction et un commentaire général.Le rapport contient aussi des annexes, parmi lesquelles des cartes, une liste des sites et un catalogue des nouvelles inscriptions nabatéennes et nabatéo-arabes. L'ensemble est par ailleurs illustré de 33 planches
Sémiotique du mythe
No full textInternational audienceLe mythe peut être appréhendé comme notion et forme discursive en sciences du langage et en sémiotique. Des lectures critiques (1858-2025) de courants variés (pré-saussuriens, structuralistes, etc.) permettent de proposer des cadres théoriques et méthodologiques pour étudier les mythes contemporains