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The collateral channel within and between countries
No full textWe examine the response of investment to real estate prices among French firms from 1994 to 2015. Using newly introduced methods and specifications, we find that investment sensitivity to real estate prices decreases with firm size: The smallest firms are at least three times more responsive to changes in collateral value compared to the largest firms. We impute these estimates onto other countries where available data lack firm-level detail. This approach allows us to assess the aggregate sensitivity of investment to real estate prices across different countries. Our results indicate significant variation in the sensitivity of aggregate investment to real estate shocks, driven by cross country differences in the size distribution of firm
The Kerbernez long-term experiment: A dataset on crop yield and soil organic matter evolution in forage crop rotations and permanent grasslands in a temperate oceanic climate
No full textInternational audienceForage crop rotations including grasslands, common in dairy systems, are known to ensure good productivity and limit the decrease of soil organic matter frequently observed in permanent arable land. A dataset was built to compile data from the Kerbernez long-term experiment, conducted in Brittany(France) from 1978 to 2005. This experiment compared the effect of different forage crop rotations fertilized with ammonium nitrate and/or slurry, with or without grassland, on forage production (quantity, quality) and changes in soil physio-chemical characteristics. These forage crop rotations were based on silage maize and cut monospecific grasslands of Italian ryegrass (Lolium multiflorum L.) or perennial ryegrass (Lolium perenne L.). More precisely, the experiment compared silage maize monocultures, rotations with silage maize and Italian ryegrass established for 6 to 18 months, and rotations with silage maize and perennial ryegrass established for three to more than 10 years. They are representative of the forage crop rotations and permanent grasslands that were at the heart of Brittany's forage revolution in the 1970s. The dataset includes information about the climate and soil conditions, the management of crops and grasslands, the evolution of topsoil organic carbon and nitrogen stocks, the inter-annual variations in crop and grassland dry matter yields and nitrogen contents. The dataset also includes characterisation of soil structural stability, particle-size soil organic matter fractions and potential soil carbon and nitrogen mineralisation at the end of the trial. It consists of fourteen csv files. This dataset can be used for a variety of purposes, namely for assessing the ability of mechanistic models to simulate soil organic matter dynamics and associated fluxes, and to estimate the influence of grassland presence and duration in forage crop rotations on such fluxes
Discrete-Element Method Study of the Effect of Ballast Layer Depth on the Performance of Railway Ballast Bed
No full textInternational audienc
On the Mechanism of Acrylate and Propionate Silyl Esters Synthesis by Ruthenium-Catalyzed Coupling of CO<sub>2</sub> with C<sub>2</sub>H<sub>4</sub> in the Presence of Hydrosilanes: Combined Experimental and Computational Investigations
No full textInternational audienceThe upcycling of CO2 to value-added chemicals using catalytic approaches constitutes a challenge in the topical area of sustainable development and use of renewable resources. We report herein on a Ru(II)-catalyzed reductive carboxylation of ethylene in the presence of hydrosilane (Et3SiH) affording acrylate and propionate silyl esters. Upon using high-throughput screening (HTS) and batch-reactor techniques, some promising catalyst systems incorporating 1,4-bis(dicyclohexylphosphino)butane (DCPB) as ligand, namely monohydrido-chloro complex Ru(H)(Cl)(CO)(DCPB)(PPh3) (Ru-2) or dihydride complex Ru(H)2(CO)(DCPB)(PPh3) (Ru-5), were identified among a few others. Detailed mechanistic studies involving the isolation of a Ru(II)-acrylate intermediate and computational investigations unveiled the possible operational mechanism leading to the construction of the acrylate platform from CO2 and ethylene. The selectivity toward the desired silyl esters is affected by side-processes (mainly CO2 hydrosilylation, ethylene hydrosilylation and dehydrogenative coupling of ethylene with hydrosilane) and could be improved by varying the substrates' concentrations (CO2/ethylene/ hydrosilane ratios), while the acrylate vs. propionate selectivity depends on the processes producing in situ H2, which is responsible for the reduction of the acrylate C=C double bond. In particular, a marked role of water on the selectivity was rationalized as a potential H2 source when used in combination with hydrosilane. A better selectivity towards the production of triethylsilyl acrylate could be achieved using dihydride complex Ru-5 as discrete precatalyst (up to 47% vs. 15% with Ru-1/DCPB), in line with the mechanistic studies
The effect of online social networks on theory of mind development among digital natives
No full textInternational audienc
Quality assessment of Ivory Coast smoked herring (Madeiran sardinella) produced by three smoking processes by physico-chemical and mid infrared spectroscopy coupled with chemometric tools: a preliminary study
No full textInternational audienceThe aim of this study was to explore the potential of mid infrared spectroscopy (MIR) and physico-chemical methods to determine the effect of smoking processes on fish quality. A total of 45 herring (Madeiran sardinella) samples collected from the Ebrié lagoon (Ivory Coast) were submitted to smoking using three different smoking conditions (improved system smoking (ISMWC), traditional oven smoking with mangrove wood (ASMW) and traditional oven smoking with rubber wood (ASRW). Physicochemical results revealed that the highest amounts for water content (46.97 ± 3.66), peroxide value: PV (29.37 ± 0.91), thiobarbituric acid reactive substances: TBARS (6.72 ± 1.22) and total volatile basic nitrogen:TVB-N (66.01 ± 2.10) were found in smoked samples with traditional smoking systems using rubberwood. Factorial discriminant analysis (FDA) with leave one-out-cross validation of MIR spectra showed clear discrimination between the three smoking techniques according to the fuel used. Samples from the ASRW group had the best discrimination, with 73.33% correct classification, while those belonging to ISMWC group presented the lowest discrimination, with 66.67% correct classification. The results obtained in this study showed that mid-infrared spectroscopy coupled with chemometric tools could be used as a rapid tool for discriminating herring samples according to the smoking process
Instrumentation and Characterisation of Mixed GO Electrical Steel Magnetic Cores
No full textInternational audienceThis paper investigates the performance implications of mixing grain-oriented electrical steel (GOES) grades in a single-phase transformer core through comprehensive characterization and instrumentation. An extensive measurement setup using B-coils and H-coils enables detailed mapping of local magnetic flux density and field strength distributions. Experimental results demonstratethat strategic grade mixing can enhance core performance, with improvements dependent on the magnetic property differences between selected grades. The findings provide insights into local magnetic behavior within mixed-grade cores, contributing to the optimization of power transformer design
Hybrid Calculation of PWM Flux Density Harmonics in a PMSM with a damper system
No full textInternational audienc
Topical Application of Cannabidiol for Muscle Recovery : A randomized, double-blinded Pilot Study on Recovery of Muscle Function After Exercise-Induced Muscle Damage
No full textInternational audienceCannabidiol (CBD), a non-psychoactive cannabinoid from the cannabis plant, has gained popularity for its anti-inflammatory, analgesic, and neuroprotective properties, along with a favorable safety profile (Gamelin et al., 2020). Since the World Anti-Doping Agency (WADA) removed CBD from its list of prohibited substances in 2018, and given its identified pharmacological effects, this compound has attracted growing interest among athletes, with its use steadily increasing in recent years (Leas et al., 2019). While some studies report positive effects of oral CBD on muscle damage markers and performance recovery, findings remain inconsistent, and the effects of topical CBD application in a sports recovery context remain largely unexplored. This pilot study aimed to investigate the effects of a topical CBD gel on muscle function, delayed-onset muscle soreness (DOMS), and blood marker of muscle damage (Myoglobin) rarely assessed in previous CBD studies following strenuous exercise designed to induce muscle damage
Accretion of the anomalous CR2 chondrite Northwest Africa 14674: Implications for the complexities of the CR parent bodies
No full textInternational audienceAn understanding of the differences between ungrouped, or anomalous, and normal carbonaceous chondrites could provide information on the population of parent bodies required to explain a chondrite group and on first solid accretion and evolution in the outer protoplanetary disk. The CR chondrites are key in this respect, as they display a unique formation history that distinguishes them from other groups. They are known to have formed between 4.1 and 4.6 Myr after CAI, with two generations of chondrules. Northwest Africa (NWA) 14674 is a CR2 anomalous (CR2-an) chondrite with very similar oxygen isotope composition, dark inclusion (DI) content, and serpentine-magnetite matrix to Al Rais (CR2-an). Both are petrologic subtype 2.3 with fresh magnesian olivine, and partly altered ferroan olivine, pyroxene, and metal. Additionally, NWA 14674 contains residual GEMS-like material at the nanoscale within preserved moderately altered areas. DI and matrix in NWA 14674 are mineralogically similar but they have different fabrics, and matrix is more porous than both DI and fine-grained rims (FGR). Matrix has aligned framboidal magnetite aggregates swathing the chondrules, suggesting slight compaction of the chondrite. Some DI have inner chondrule fragments and concentric layers richer and poorer in magnetite, indicating formation as accretionary pellets and lapilli: they are pebbles rather than clasts. The framboidal magnetite abundance is consistent with an alkaline alteration fluid potentially due to NH3 ice mixed with the more common water ice, which implies late distal accretion. Comparison with the CR chondrites Bells (regolith-like) and NWA 801 (with high-pressure clasts) indicates that a complex history involving inward drift, disruption of the grandparent body, and reaccretion of debris along with chondrules, DI pebbles, and dust is required to explain CR chondrite formation. The diverse facies observed in CR chondrites may be explained by the formation of relatively large parent bodies, comprising distinct layers (core to regolith). Some material has been inherited from a chondritic protoplanet that formed during the oligarchic growth phase of planetary formation. Subsequently, this initial body underwent disruption and partial reaccretion into the CR parent body