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Enhanced propene oxidation over yttrium-doped cryptomelane MnO<sub>2</sub> catalysts: synergistic effects of structural modification and oxygen mobility
No full textfffInternational audienceliste mot clef
Data Complexity of Querying Description Logic Knowledge Bases under Cost-Based Semantics
No full textInternational audienceIn this paper, we study the data complexity of querying inconsistent weighted description logic (DL) knowledge bases under recently-introduced cost-based semantics. In a nutshell, the idea is to assign each interpretation a cost based upon the weights of the violated axioms and assertions, and certain and possible query answers are determined by considering all (resp.\ some) interpretations having optimal or bounded cost. Whereas the initial study of cost-based semantics focused on DLs between and , we consider DLs that may contain inverse roles and role inclusions, thus covering prominent DL-Lite dialects. Our data complexity analysis goes significantly beyond existing results by sharpening several lower bounds and pinpointing the precise complexity of optimal-cost certain answer semantics (no non-trivial upper bound was known). Moreover, while all existing results show the intractability of cost-based semantics, our most challenging and surprising result establishes that if we consider ontologies and a fixed cost bound, certain answers for instance queries and possible answers for conjunctive queries can be computed using first-order rewriting and thus enjoy the lowest possible data complexity (). </div
Contrasting impacts of grazing and shrub encroachment on microbial resource limitation in arid grasslands
No full textInternational audienceGrazing and shrub encroachment are primary drivers of ecological change in arid grasslands, influencing biodiversity, plant productivity, and soil nutrient cycling. However, their impacts on soil functioning and microbial resource limitations remain largely unknown, particularly as carbon and nutrient limitations may differ between shrub- or herb-dominated grassland. To address this gap, we performed parallel grazing experiments in herbaceous and shrub communities in northern China to examine how grazing, shrub encroachment and their interactions influence soil microbial limitations by altering enzyme activities. Our results show that grazing alleviated microbial phosphorus limitation, likely due to nutrient inputs from grazers through excreta and trampling-induced soil disturbances that enhanced phosphorus availability. In contrast, shrub encroachment mitigated microbial carbon limitation, possibly driven by increased soil organic matter accumulation and root exudation. These effects were also mediated by indirect changes in soil total and available nutrient pools, which were crucial in regulating microbial resource limitations. However, we found interactive effects between grazing and shrub encroachment did not significantly impact microbial resource limitations, suggesting that these factors operate independently in shaping soil microbial dynamics. Our findings emphasize the distinct roles of grazing and shrub encroachment in regulating microbial nutrient constraints, highlighting the importance of soil nutrient availability over plant community attributes in driving microbial responses. These results provide valuable insights for grassland management under global change, underscoring the need for adaptive strategies that integrate both aboveground vegetation shifts and belowground nutrient cycling processes
Daily life of persons with chronic disorders of consciousness: advice of families and healthcare professionals
No full textInternational audienc
Tuning photochemical and biological properties of nitro-nitrosyl ruthenium complexes via nitrogen heterocycle geometry: Benzimidazole vs. Indazole
No full textInternational audienceTwo new nitrosyl ruthenium complexes [RuNO(L) 2 (NO 2 ) 2 OH] (where L = indazole (HInd), benzimidazole (Benz-im)) were synthesized and characterized. The XRD structural data were obtained for acetate salt of the indazole complex -[RuNO(HInd) 2 (NO 2 ) 2 OH 2 ]AcO•0.5HOAc (1a). Two crystal structures with different solvent environments were determined for the benzimidazole complex: [RuNO(Benzim) 2 (NO 2 ) 2 OH]•H 2 O•EtOH (2) and [RuNO(Benz-Im) 2 (NO 2 ) 2 OH]•2iPrOH (2a). The photolysis processes of NO release of the synthesized compounds in DMSO and phosphate-buffered saline (PBS, pH = 7.4) were investigated using a flow-through system coupled with simultaneous measurement of IR and optical absorption spectra under irradiation with 450 nm light. The quantum yields of NO release in DMSO were determined to be 11.4 ± 0.3% and 6.0 ± 0.2% for HInd and Benz-im complexes, respectively. DFT calculations of the optical absorption spectra and molecular orbitals revealed differences in the HOMO orbitals of the complexes, despite their structural similarity. This finding may explain their quantum yield difference. Complexes before and after photolysis in DMSO/acetonitrile mixture were investigated using the ESI-MS method. Prior to photolysis, the predominant species for both complexes were the initial molecular ions observed either as adducts with Na⁺ or through loss of H⁺, OH⁻, or NO₂⁻. Following photolysis, species resulting from NO loss substituted by water or DMSO were detected. Dark and photoinduced cytotoxicity were studied against human lung carcinoma cells (A549) and non-tumor human lung fibroblasts (MRC-5).Without irradiation, the IC 50 values were 27 ± 3 μM and >75 μM for the A549 line, and 24.9 ± 0.4 μM and >75 μM for the MRC-5 line, for Hind and Benz-im complexes, respectively. Irradiation did not lead to significant changes in cytotoxicity. The lipophilicity tests in PBS/n-octanol were conducted for both complexes to tackle their difference in cell membrane permeability. The logP₃₀₀ values for complexes with HInd and Benz-im were 1.21 and 0.32, respectively. This difference may partially account for the higher permeability of HInd complex resulting in higher cytotoxic effect.</div
A Logic-based Algorithmic Meta-Theorem for Treedepth: Single Exponential FPT Time and Polynomial Space
No full textAccepted at SODA 2026, it will be published soon.International audienc
A comprehensive study of Surface Water and Ocean Topography (SWOT) Pixel Cloud data for flood extent extraction
No full textInternational audienceCurrent disaster and emergency management services produce flood maps within hours using satellite data. To handle large-scale events efficiently, a reliable automated method is needed to generate an initial flood extent map, which can then be refined manually.Launched in December 2022, the Surface Water and Ocean Topography (SWOT) satellite, equipped with the Ka-band Radar Interferometer (KaRIn), provides high-resolution radar observations used here for flood detection. While not initially designed for detailed flood mapping in vegetated or urban regions, the performance of SWOT’s Pixel Cloud products was assessed during four major flood events in Greece, France, Brazil, and the USA. Each event is paired with Sentinel-1 or Sentinel-2 imagery within a 3-hour time frame, providing a valuable opportunity to compare and evaluate SWOT’s flood detection capabilities.Three radar variables of the Pixel Cloud products are studied for extracting flood extents: , coherent power, and interferometric coherence — which is computed from the two complex interferograms. They are compared to the built-in classification and flood masks computed from Sentinel-1/2. The study demonstrates the capabilities of the SWOT satellite in detecting flooded vegetation, flooded urban areas, and even regions with high snow cover. However, limitations are observed: (1) when high soil moisture is observed, causing signal saturation, (2) SWOT can be sensitive to the incidence angle, both of which lead to less reliable flood extent estimation. These findings highlight the potential of SWOT satellite for improving global flood mapping, as well as the need for further exploration to address current limitations and enhance flood monitoring capabilities in the near future
Improving Access to Nuclear Medicine in Island Regions: A Cost-Minimization Analysis of Radiopharmaceutical Supply Strategies
No full textInternational audienc
