Archives ouvertes de Paris-Saclay
Not a member yet
272730 research outputs found
Sort by
Markups, Markdowns, and Bargaining in a Vertical Supply Chain
No full textThis article bridges monopoly, monopsony, and countervailing power theories to analyze their welfare implications in a vertical supply chain. We develop a bilateral monopoly model with bargaining that accommodates upstream monopsony and downstream monopoly power. In equilibrium, the ‘‘short-side rule'' applies: the quantity exchanged is determined by the firm willing to trade less. Welfare is maximized when each firm's bargaining power exactly countervails the other's market power. Otherwise, double marginalization arises in the form of double markdownization under excessive downstream bargaining power, or double markupization under excessive upstream bargaining power. We offer novel insights for price regulation (e.g., price floors) and competition policy
Study of SIDIS Unpolarized Cross Sections from a He Target with the Solenoidal Large Intensity Device at JLab
No full textInternational audienceIn this paper we present a detailed impact study of semi-inclusive deep inelastic scattering unpolarized cross sections' measurements using the proposed SoLID apparatus at Jefferson Lab. This type of data, collected at large Bjorken , moderate values of and small values of the transverse momentum of produced hadrons, , allows to study transverse momentum dependent (TMD) parton distribution and fragmentation functions in a still poorly explored region. We present the projected results for charged light mesons based on simulated data. For the azimuthal-angle integrated cross sections we adopt the TMD framework up to the next-to-next-to-next-to-leading-logarithmic (N3LL) accuracy, while a simpler TMD parton model is employed for the study of azimuthal angular dependencies
Psychosocial outcomes among adults with type 1 diabetes using a tubeless automated insulin delivery system compared with sensor augmented pump therapy: A randomised, parallel‐group clinical trial sub‐study
No full textInternational audienceAims: Beyond their glycaemic benefits, automated insulin delivery (AID) systems can provide psychosocial benefits for people with type 1 diabetes (T1D) and improve quality of life. In this study, we evaluated psychosocial outcomes in adults with T1D using the tubeless Omnipod® 5 AID System compared with sensor augmented pump (SAP) therapy.Materials and methods: As part of a 13-week multicentre, parallel-group, randomised controlled trial comparing intervention (tubeless AID) and control (SAP) groups (2:1), adults aged 18-70 years with T1D completed validated psychosocial questionnaires assessing health-related quality of life (European Quality of Life 5 Dimensions 3 Level Version [EQ-5D-3L] index score and visual analogue scale [VAS]), the impact of diabetes on quality of life (DAWN2 Impact of Diabetes Profile [DIDP]), sleep quality (Pittsburgh Sleep Quality Index [PSQI]), system usability (System Usability Scale [SUS]) and perceptions before and experiences after using AID systems (INsulin Dosing Systems: Perceptions, Ideas, Reflections and Expectations [INSPIRE]).Results: The intervention group saw greater score improvements than the control group for all measures evaluated, including health-related quality of life (EQ-5D-3L VAS, p = 0.01; EQ-5D-3L index score, p = 0.002), impact of diabetes on quality of life (DIDP, p = 0.004), perceived system usability (SUS, p < 0.0001) and sleep quality (PSQI, p = 0.03). INSPIRE scores, determined only for the intervention group, were high at baseline and follow-up, suggesting positive perceptions of tubeless AID.Conclusions: This randomised controlled trial demonstrated that the use of a tubeless AID system improved psychosocial measures to a greater extent than SAP therapy. These results contribute to the growing body of evidence demonstrating that AID may improve quality of life and alleviate some of the burden associated with diabetes self-management in adults with T1D
Polypyrrole-Hemicellulose Composite Based Electrochemical Sensor for Pb(II) Detection and Quantification in Water
No full textInternational audienceA screen-printed carbon electrode SPCE was modified by the incorporation of polypyrrole (Ppy), as a conductive polymeric matrix and hemicellulose extract from Cactus as a hydrophilic biopolymer. This polypyrrole-hemicellulose composite film (Ppy-HEM@SPCE) was designed for the selective and sensitive detection of Pb(II) trace in aqueous media by square wave anodic stripping voltammetry (SWASV). The porous structure of the Ppy film immobilized hemicellulose homogeneously, providing an even distribution of hydroxyl and carboxyl groups throughout the coating. These functional groups allowed the coordination of Pb(II) ions. The Ppy-HEM@SPCE composite film was characterized by different electrochemical and physicochemical techniques revealing the efficient association and improved coordination properties. Under optimized conditions, a linear relationship was obtained between the redox current and metal ion concentrations ranging from 1 pM to 1 μM and a detection limit of 1 pM was determined. The Ppy-HEM@SPCE composite film demonstrated excellent repeatability, reproducibility as well as long-term stability and potential of regeneration. In addition, the detection of Pb(II) was successfully performed in various real water samples as demonstrated by comparison with ICP/MS as a classical detection method
Reconstruction of SINR Maps from Sparse Measurements using Group Equivariant Non-Expansive Operators
No full textAs sixth generation (6G) wireless networks evolve, accurate signal-to-interference-noise ratio (SINR) maps are becoming increasingly critical for effective resource management and optimization. However, acquiring such maps at high resolution is often cost-prohibitive, creating a severe data scarcity challenge. This necessitates machine learning (ML) approaches capable of robustly reconstructing the full map from extremely sparse measurements. To address this, we introduce a novel reconstruction framework based on Group Equivariant Non-Expansive Operators (GENEOs). Unlike data-hungry ML models, GENEOs are low-complexity operators that embed domain-specific geometric priors, such as translation invariance, directly into their structure. This provides a strong inductive bias, enabling effective reconstruction from very few samples. Our key insight is that for network management, preserving the topological structure of the SINR map, such as the geometry of coverage holes and interference patterns, is often more critical than minimizing pixel-wise error. We validate our approach on realistic ray-tracingbased urban scenarios, evaluating performance with both traditional statistical metrics (mean squared error (MSE)) and, crucially, a topological metric (1-Wasserstein distance). Results show that while maintaining competitive MSE, our method dramatically outperforms established ML baselines in topological fidelity. This demonstrates the practical advantage of GENEOs for creating structurally accurate SINR maps that are more reliable for downstream network optimization tasks
Panorama rapide de l’actualité « Numérique » des semaines du 15 décembre 2025 au 5 janvier 2026
No full textNational audiencePrésentation et analyse de l'actualité du droit du numérique :Données personnes-RGPD : le système de caméras-piétons correspond à une collecte directe et non indirecte: Arrêt de la Cour de justice dans l'affaire C-422/24 Storstockholms Lokaltrafik- Surveillance au travail : le Conseil d’État valide partiellement les outils de suivi d’Amazon : CE, N° 492830, 23 décembre 2025- 3. Logiciels de gestion sociale et RGPD : la CNIL sanctionne NEXPUBLICA France : Délibération de la formation restreinte n° SAN – 2025-015 du 22 décembre 2025- 4. L’Arcep face au projet de loi DADUE : un avis sans portée contraignante mais stratégique : Avis ARCEP du 5 janvier 2026II. IA-Quand l’IA invente la jurisprudence : : un avertissement explicite du juge aux praticiens : TJ de Périgueux, pôle social, n° RG 23/00452, n° Portalis DBXP-W-B7H-EJLQIII. Plateforme- Affaire Shein : la justice refuse le blocage, l’État ne désarme pas : Tribunal judiciaire de Paris, 19 décembre 2025, n° RG252/786- Affaires Airbnb : la société n’a pas la qualité d’hébergeur et ne bénéficie pas du régime de responsabilité des hébergeurs de contenus : Cass. Com. 7 janvier 2026, n°23-22.723 et Cass. Com 7 janvier 2026, n° D 24-13.163- Affaire Jean Pormanove / Kick : Le TJ de Paris rejette le blocage de la plateforme Kick.com mais ordonne la suppression des contenus violents: TJ Paris, 19 décembre 2025, N° RG 25/57054 - N°Portalis : 352J-W-B7J-DAY6
Holocene climatic changes in the Kerguelen archipelago (South Indian Ocean) based on marine and lacustrine palaeoclimatic archives
No full textInternational audienceClimatic variability in the Southern Hemisphere is largely controlled by the latitudinal position of the Southern Hemisphere Westerly Winds (SHW), whose migration influences precipitation, temperature, and Antarctic upwelling. This study presents the results of analyses of two lacustrine sediment cores from Lake Armor, located on the subantarctic Kerguelen Islands (49 • 15′S, 69 • 10′E), within the SHW belt. Lipid biomarkers (Glycerol Dialkyl Glycerol Tetraethers, n-alkanes, and their hydrogen isotopes) were used to reconstruct mean annual air temperature above freezing (MAF) and humidity conditions. These records are compared with a high-resolution diatom-based summer sea surface temperature (SST) reconstruction from marine core MD11-3353, situated 150 km southwest of Lake Armor. In the late glacial and Early Holocene, our results reveal a period of warm air temperature, comparable to current values and very warm sea surface temperature, 5°C above the current values. Around 9000 cal a BP, an abrupt transition occurred, marked by a cooling of 5°C in SST and 1.5°C in MAF, interpreted as a northward migration of the SHW and associated oceanic fronts. The Mid-to-Late Holocene period is characterized by pronounced MAF variability, including a notably warm interval between 3000 and 2000 cal a BP, when n-alkane dD suggests the prevalence of wetter conditions. Since ~250 cal a BP, a southward migration of the SHW has produced a 2.5°C rise in MAF. Our findings are overall consistent with previous studies from the Indian Ocean, but permit us to go a step further as by comparing SSTs and air temperatures. This suggests that SST is not a reliable predictor of air temperature on the Kerguelen Islands, particularly during the Early Holocene. We hence argue that Kerguelen air temperature is predominantly controlled by the position of westerly winds, as an indicator of reorganisations in air mass trajectories
Simulating transgenerational hologenomes under selection with RITHMS
No full textInternational audienceA holobiont is made up of a host organism together with its microbiota. In the context of animal breeding, the holobiont can be viewed as the single unit upon which selection operates. Therefore, integrating microbiota data into genomic prediction models may be a promising approach to improve predictions of phenotypic and genetic values. Nevertheless, there is a paucity of hologenomic transgenerational data to address this hypothesis, and thus to fill this gap, we propose a new simulation framework. Our approach, an R Implementation of a Transgenerational Hologenomic Model-based Simulator (RITHMS) is an open-source package. It builds upon simulated transgenerational genotypes from the Modular Breeding Program Simulator (MoBPS) package and incorporates distinctive characteristics of the microbiota, notably vertical and horizontal transmission as well as modulation due to the environment and host genetics. In addition, RITHMS can account for a variety of selection strategies and is adaptable to different genetic architectures. We simulated transgenerational hologenomic data using RITHMS under a wide variety of scenarios, varying heritability, microbiability, and microbiota transmissibility. We found that simulated data accurately preserved key characteristics across generations, notably microbial diversity metrics, exhibited the expected behavior in terms of correlation between taxa and of modulation of vertical and horizontal transmission, response to environmental effects and the evolution of phenotypic values depending on selection strategy. Our results support the relevance of our simulation framework and illustrate its possible use for building a selection index balancing genetic gain and microbial diversity and for evaluating the impact of partially observed microbiota data. RITHMS is an advanced, flexible tool for generating transgenerational hologenomes under selection that incorporate the complex interplay between genetics, microbiota and environment
Bulletin de veille du réseau d'écotoxicologie terrestre et aquatique N°83
No full textINRAE, réseau ECOTOX → A paraîtreBulletin de veill
Optimal execution on Uniswap v2/v3 under transient price impact
No full textWe study the optimal liquidation of a large position on Uniswap v2 and Uniswap v3 in discrete time. The instantaneous price impact is derived from the AMM pricing rule. Transient impact is modeled to capture either exponential or approximately power-law decay, together with a permanent component. In the Uniswap v2 setting, we obtain optimal strategies in closed-form under general price dynamics. For Uniswap v3, we consider a two-layer liquidity framework, which naturally extends to multiple layers. We address the problem using dynamic programming under geometric Brownian motion dynamics and approximate the solution numerically using a discretization scheme. We obtain optimal strategies akin to classical ones in the LOB literature, with features specific to Uniswap. In particular, we show how the liquidity profile influences them