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In Vitro and In Vivo Evaluation of Wound Dressing Based on PCL Nanofibers Loaded With Linum usitatissimum Extract
No full textInternational audienceIn the present study, we fabricated nanofibers‐based wound dressing containing Linum usitatissimum (LOH) extract. The nanofibers were fabricated and characterized using electrospinning (applied voltage: 20 kV, feeding rate: 0.5 mL/min, and tip‐to‐collector distance: 10 cm). The SEM results indicated that the fabricated nanofibers have a straight and uniform morphology, and the diameter of PCL nanofibers loaded with 5%, 10%, and 15% of extract was 335 ± 45 nm, 438 ± 79 nm, and 471 ± 76 nm, respectively. Moreover, the nanofibers have porosity values in the range of 40%–55%. The in vitro biological evaluations revealed that adding the extract improved the biological performance (antioxidant, hemocompatibility, and cytocompatibility) of the pure PCL nanofibers. The in vivo study showed that the fabricated nanofibers improved the induced wound's healing process and enhanced the tissue's antioxidant state. These observations showed that combining electrospun nanofibers with LOH extract resulted in interactive and bioactive wound dressing nanofibers
Versatile coordination of iron dichloride with N-(fluoro)-aryl-substituted iminopyridine ligands: Synthesis, structures, magnetic properties and polymerization of isoprene
No full textInternational audienceAs iron is one of the most abundant resources on earth and a low toxicity transition metal, it is only natural that chemical reactions and catalysis revolving around this resource have attracted attention. Over the past three decades, considerable progress has been made in the field of coordination insertion polymerization using iron catalysts.[1] Of particular interest is a type of iron-based complexes supported by iminopyridine ligands, which enables the stereoselective cis or trans polymerization of conjugated dienes depending on the substituent on the N-imino group.[2] In this study, we focus on this particular family of complexes, more precisely on iminopyridine N-aryl fluorinated iron complexes {with iminopyridine 2-[(Ar)N=C(R)]C5H4N, where Ar = 3,5-(CF3)2C6H3 and R = H (L1) or CH3 (L3); Ar = C6H5 and R = H (L2) or CH3 (L4)}. Four complexes were isolated as single crystals, and their molecular structures were elucidated by X-ray diffraction, revealing distinct coordination depending on the nature of the ligand (Fig. 1). Mössbauer spectroscopy and magnetic susceptibility measurements confirmed the presence of Fe(II) in a high-spin state across all complexes, which was further supported by DFT calculations
Functional distance and US global banks’ foreign branch lending
No full textInternational audienceThis paper examines the significance of functional distance in explaining the lending behavior of foreign branches of global banks. We operationalize functional distance, or the distance between the global bank's headquarters and the host country of the foreign branch, along a geographic, linguistic, and cultural dimension. Analyzing the lending activities of US global banks' foreign branches in 38 countries from 2001 to 2020, we find that geographic and linguistic functional distance has an adverse effect on local lending. We further find that a host country's institutional quality can moderate the effect of functional distance on local lending
Climate Shocks and U.S. Bank Stability
No full textThis paper investigates the effects of systemic climate variability on U.S. banking stability using the El Niño-Southern Oscillation (ENSO) as a quasi-natural experiment. In contrast to studies focusing on rare, localized natural disasters, we examine how persistent and spatially heterogeneous ENSO-induced climate anomalies-especially those associated with the often-overlooked La Niña phase-affect banks across the continental United States. ENSO is the most influential source of interannual climate variation on Earth and provides a compelling setting to study the transmission of exogenous physical risks to the financial sector. We construct a 30-year quarterly panel of over 800,000 bank-quarter observations (1994-2023), combining detailed financial data with geolocated branch networks and high-resolution teleconnection estimates of local temperature anomalies. Our empirical strategy combines three key elements: a regime-based climate shock identification grounded in recent climate science, a granular spatial matching of institutions to localized exposure, and a dynamic panel framework based on local projections. Our results show that strong La Niña shocks reduce the distance to default by roughly 20%, with effects peaking between 7 and 11 quarters after the shock. These disruptions operate primarily through rising credit risk, lower profitability, and weaker solvency-particularly in banks with large real estate exposure, broad but climate-sensitive geographic footprints, and sizable balance sheets. These findings underscore the need for prudential regulation to incorporate granular, forward-looking metrics of physical climate risk, especially as ongoing climate change is expected to increase the frequency and intensity of ENSO events
Interactive Exploration of Plan Spaces
No full textInternational audienceMany planning applications require not only a single solution but benefit substantially from having a set of possible plans from which users can select, for example, when explaining plans. For decades, research in classical AI planning has primarily focused on quickly finding single plans. Only recently researchers have started to investigate preferences, enumerate plans by top-k planning, or count plans to reason about the plan space. Unfortunately, reasoning about the plan space is computationally extremely hard and feeding many similar plans to the user is hardly practical. To circumvent computational shortcomings while still being able to reason about variability in plans, faceted actions have been introduced very recently. These are meaningful actions that can be used by some plan but are not required by all plans. Enforcing or forbidding such facets allows for navigating even large plan spaces while ensuring desired properties quickly and step by step. In this paper, we illustrate an industrial challenge, the Beluga logistics problem of Airbus, where reasoning with facets enables targeted plan space navigation. We present an approach to handle large plan spaces iteratively and interactively and present a tool that we call PlanPilot
Lactic acid fermentation enhances antioxidant potential of chicory by-products for functional food applications
No full textInternational audienceChicory (Cichorium intybus) processing generates substantial volumes of underutilized by-products, including peelings and roots, which are rich in polyphenols and other bioactive compounds with potential health benefits. This study explored the use of lactic acid fermentation as a sustainable strategy to valorize these residues into functional food ingredients. Eight strains of Lactiplantibacillus plantarum and Lactobacillus reuteri, including two isolates from the native Witloof chicory (Belgian endive) microbiota, were screened for their ability to ferment four types of chicory-derived by-products. Belgian endive peelings (EPBU) emerged as the most promising matrix based on bacterial growth, antioxidant potential, and hepatoprotective activity in ethanol-stressed hepatic cells. Antioxidant capacity was evaluated using both a biochemical assay (DPPH) and a cell-based ROS assay in hepatic and intestinal cell lines. While the DPPH assay confirmed the high baseline antioxidant activity of EPBU maceration, fermentation with strain 31c significantly enhanced cellular ROS scavenging, achieving up to a 17-fold reduction, among the more pronounced antioxidant enhancements observed for fermented plant-based matrices. Metabolomic analysis of fermented EPBU revealed the presence of chlorogenic acid and consistent elevation of compounds associated with fermentation pathways. These findings demonstrate the potential of lactic acid fermentation to improve the bioactivity of chicory by-products, supporting their use in sustainable food and nutraceutical applications
Enhancing photovoltaic panel efficiency through Water-Cooling: A parametric comparative evaluation of energetic, economic, and environmental benefits
No full textInternational audienceThe pressing need for more effective solar technology is highlighted by the global transition away from fossil fuels and toward renewable energy sources. Despite the enormous potential of photovoltaic (PV) panels, efficiency losses in high-temperature conditions limit their performance. The purpose of this study is to theoretically evaluate the energy, financial, and environmental advantages of different water-cooling techniques intended to improve the sustainability and operating efficiency of PV panels. In contrast to traditional research, this work quantifies increases in energy output, cost savings, and CO2 emission reductions across various cooling configurations by a thorough parametric analysis inside a single theoretical framework. To simulate how various water-cooling methods affect PV panel performance, a mathematical parametric model was created. Energy production, cost savings, and carbon footprint reduction were among the key performance metrics computed and compared for PV applications in relation to the consumption ratio R, which is defined as the ratio of the actual building load to the maximum PV power output, or the amount of energy consumed by the house from the PV panels. With an annual energy gain of 1354.10R kWh per panel, cost savings of 582.26R USD, and CO2 emission reductions of 785.37R kg, jet water impingement cooling (JWPV) outperformed the other technologies under evaluation. However, with energy gains of 1061.53R kWh, savings of 456.46R USD, and CO2 reductions of 615.68R kg, evaporative cooling (EPV) produced the least amount of improvement. These results highlight how important efficient cooling is to improving PV panel performance and developing sustainable solar energy solutions
Optimization of the tooth geometry for axial flux machine with Non-Grain Oriented and Grain Oriented electrical steel
No full textInternational audienceAxial flux permanent magnet machines (AFPMM) are characterized by a very good torque-to-weight ratio and high energy efficiency, which makes them extremely attractive for applications such as electric vehicles, drones or even wind turbines. They are often compared with the best radial flux motors in terms of energy consumption as they can operate at over 95% efficiency. Taking as a reference an already studied AFPMM, this paper aims to improve its global performances, by segmenting the magnetic circuit and by using high-performance materials. A mixed structure constituted of a yoke made with Non-Oriented Grain Electrical Steel and teeth using Grain Oriented Electrical Steel is proposed. The optimization concerns the tooth geometry, considering the strong GOES anisotropy
Evidence for Methylaluminoxane (MAO) Molecular Structure and Reactivity from Ultrahigh Magnetic Field <sup>27</sup>Al MAS NMR Spectroscopy Combined with DFT Calculations
No full textInternational audienceThe structure and reactivity of methylaluminoxane (MAO), a reagent of major interest for olefin polymerization, both industrially and academically, has been probed using ultrahigh magnetic field solid‐state NMR (28.2 T, 1200 MHz for 1H Larmor frequency). High resolution methods combined with density functional calculations allowed for the identification and quantification of five major aluminum sites, providing precise information on the structure of MAO at the molecular level. Based on reactivity studies with THF and [ZrCp2AlMe2], the main reactive centers are identified as bismethyl aluminum species stabilized via a bridging methyl group from a neighboring Al center, featuring both high chemical shift and quadrupolar coupling constants (162 ppm and 27.4 MHz, respectively). This approach demonstrates the ability to monitor the chemistry of MAO with unprecedented precision, enabling a state‐of‐the‐art understanding of its structure and reactivity