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Corrigendum to ‘Application of Ventilated Solar Façades to enhance the energy efficiency of buildings: A comprehensive review’ Energy Rep. 13 (June) (2025) 1266–1292/2352–4847
No full textInternational audienceEnhancing building energy performance, driven by growing concerns about energy conservation and sustainable development, is renewing interest in passive solar systems. Among the various passive technologies, the strategic development of ventilated solar façade has received increasing attention from engineers and architects in recent years. Depending on their configurations and associated design principles, ventilated solar façade haveproven to reduce heating and cooling loads by harnessing solar energy. This article provides a comprehensive review of the state-of-the-art research on passive ventilated solar façade and their integration into building envelopes, focusing on their respective enhancements in terms of energy efficiency and limiting the use of conventional space heating and cooling methods. The different works are divided into four categories based on air circulation techniques. This study is intended to be a valuable resource for academic researchers and a source of inspiration for architects and engineering designers in the development of façade and thermal systems
Experimental and simulated data for crop and grassland production and carbon-nitrogen fluxes
No full textInternational audienceMulti-year datasets from field experiments and simulations at five agricultural sites in the Northern Hemisphere were developed for three cropland sites in Ottawa (Canada), Grignon (France) and Delhi (India) and two grassland sites at Laqueuille Sándor et al. 2024, Open Data Journal for Agricultural Research, vol. 10, p. 22-27 23 (France) and Easter Bush (UK). The cropland sites have rotations with wheat, triticale, maize, rapeseed, soybean, phacelia and rice, as well as periods of bare fallow. Cattle (Laqueuille) or mixed cattle and sheep (Easter Bush) graze in the two grassland sites. Fielddata were collected between 2003 and 2012 for three to eight years, including grain yield/above‐ground net primary productivity, nitrous oxide emissions, carbon fluxes (gross primary production, net ecosystem exchange, ecosystem respiration), together with daily weather data (solar radiation, maximum and minimum temperatures, precipitation, windspeed, relative humidity, vapour pressure), soil properties, and records of crop and grassland management. Simulated outputs are from 23 models: 11 crop models, eight grassland models and four models simulating both systems
Potential of Bio-Sourced Oligogalacturonides in Crop Protection
No full textInternational audienceDuring plant development or interactions with pathogens, modifications of the plant cell wall occur. Among the enzymes involved, pectinases, particularly polygalacturonases (PGases), play a crucial role in the controlled hydrolysis of cell wall polysaccharides, leading to the formation of oligogalacturonides (OGs). These pectin-derived fragments act as key elicitors of plant defense responses, stimulating innate immunity and enhancing resistance to pathogens by modulating the expression of genes involved in immune responses and inducing the production of defense compounds. OGs are of particular interest for plant protection as a natural alternative to conventional phytosanitary products as they can be obtained through chemical, thermal, or enzymatic degradation of plant biomass. In a sustainable approach, agricultural by-products rich in pectin, such as citrus peels, apple pomace, or sugar beet pulp, offer an eco-friendly and cost-effective alternative for OG production. Thus, the current review aims to (i) update the state of the art about the different methods used to produce OGs, (ii) explore the potential of OGs as bio-based biocontrol molecules, and (iii) examine the relevance of new pectin sources for OG production
Novel approach based on removal of Metalaxyl by Advanced Oxidation process and hybrid-process: identification and mechanism pathway
No full textInternational audienceIn this study, three processes, Fenton, photo-Fenton, and photo-Fenton/adsorption hybrid, were evaluated for their ability to remove the fungicide Metalaxyl (MTX) from water. For the photo-Fenton and Fenton processes, three parameters (i.e. ferrous ion concentration, hydrogen peroxide and the pH of the aquatic medium) were optimized using the Doehlert three-parameter experimental design and response surface methodology. Metalaxyl degradation was determined by Liquid chromatography instrument coupled with a diode array detector. The mathematical models obtained were validated for each process. The optimal conditions were 225 mg L−1, mg L−1 and pH = 3.4 for the both Fenton and photo-Fenton process. Under these conditions, 22% of Metalaxyl degraded during the photo-Fenton process and 20% during the Fenton process. The adsorption/photo-Fenton hybrid process was developed to achieve total removal of Metalaxyl using activated carbon elaborate from vegetable waste. This objective was reached after 240 min using a two-stage process, 120 min per stage, under the following conditions: =25 mg L−1, 382 mg L−1and =100 mg L−1 for the first stage and =10 mg L−1, 133 mg L−1and = 34 mg L−1 for the second one. A novel combination of a quick, easy, cheap, effective, rugged, and safe extraction method, pre-concentration by evaporation and Gas Chromatography coupled with triple quadrupole Mass Spectrometry analysis was used to identify the photo-degradation by-products at ultra-trace levels. Five by-products were identified and three possible degradation pathways were also proposed
Early sensorimotor restriction in rats induces age-dependent mitochondrial alterations in skeletal muscles and brain structures
No full textInternational audienceA sedentary lifestyle can lead to motor and cognitive deficits, increasing the risk of neurodegenerative diseases in ageing. Emerging hypotheses suggest that these functional alterations may be related to energy metabolism. Indeed, ATP produced by mitochondria is essential for muscle contraction, neurotransmission and brain plasticity processes. Although a sedentary lifestyle has been associated with mitochondrial alterations in skeletal muscle, the potential effects on brain structures have yet to be investigated. The present study aimed to determine whether early sensorimotor restriction (SMR) alters mitochondrial metabolism in rat muscles and brain structures. Enzyme activities of citrate synthase (CS) and respiratory chain complexes I, II and IV were measured using a spectrophotometric technique and mitochondrial respiration was assessed using high-resolution respirometry in two hind limb muscles [soleus and extensor digitorum longus (EDL)] and four brain structures (sensorimotor cortex, striatum, prefrontal cortex and hippocampus) in control rats and rats experiencing early SMR from birth to day 28. Mitochondrial enzyme activities decreased in the soleus (complexes I and II), in the EDL (complex I) and in the hippocampus (complexes I and IV) in an age-dependent manner, whereas no effect was observed in other brain structures. CS activity decreases in the soleus and increases transiently in the striatum and sensorimotor cortex at postnatal day 15. Mitochondrial respiration was reduced in the soleus and in the sensorimotor cortex (CI and CI+CII). Early SMR appears to induce quantitative and qualitative mitochondrial alterations in skeletal muscles and certain brain structures involved in cognitive and motor processes
Les derniers musiciens du roi 1761-1792
No full textInternational audienceAlors que la monarchie lance ses derniers feux, la Musique du roi recherche l’excellence en regroupant, comme au Grand Siècle, les meilleurs artistes du royaume et recrute jusqu’au-delà des frontières. Castrats italiens, enfants de chœur et autres chanteurs aux voix puissantes composent un chœur formidable, admiré par Leopold Mozart. L’orchestre n’est pas en reste, dont les virtuoses parmi lesquels le jeune Rodolphe Kreutzer « emportent la musique à la première vue quelque difficile qu’elle soit ». Chaque jour, à la chapelle, à l’opéra ou dans les salons, la musique composée par les chefs de cet ensemble d’élite résonne dans les résidences royales. C’est à Versailles qu’habitent la plupart de ces musiciens. Ils constituent un groupe social homogène, soudé par des liens forts qui dépassent la complicité musicale : mariages heureux ou non, parrainages, amitiés s’y épanouissent en une sociabilité qui s’étend à l’ensemble des serviteurs de la Cour et au voisinage versaillais. Ces quelque 400 hommes et femmes laissent entrevoir l’intimité de leurs logis, entrouvrent la porte de leur culture et de leurs sentiments. Acteurs du cérémonial monarchique, ils permettent aussi une approche originale de la société urbaine des dernières décennies de l’Ancien Régime
Numerical modeling of hydrogel scaffold anisotropy during extrusion-based 3D printing for tissue engineering
No full textInternational audienceExtrusion-based 3D printing is a widely utilized tool in tissue engineering, offering precise 3D control of bioinks to construct organ-sized biomaterial objects with hierarchically organized cellularized scaffolds. The internal organization of scaffold constituents must replicate the structural anisotropy of the targeted tissue to effectively promote cellular behavior during 3D cell culture. The choice of polymers in the bioink and extrusion process topological properties significantly impact tissue engineering constructs' structural anisotropy and cellular response. Our study employed a hydrogel bioink consisting of fibrinogen, alginate, and gelatin, providing biocompatibility, printability, and shape retention post-printing. Topological properties in flowing polymers are determined by macromolecule conformation, namely orientation and stretch degree. We utilized the micro-macro approach to describe hydrogel macromolecule orientation during extrusion, offering a two-scale fluid behavior description. The study aimed to use the Fokker-Planck equation to represent constituent population (polymer chain) state within a hydrogel's representative elementary volume during extrusion-based 3D printing. Our findings indicate that a high shear rate drives constituent orientation in tubular nozzle syringe setups, overcoming fluid rheological behavior. Additionally, the interaction coefficient (C_i), representing microscopic fluid particle interaction, surpasses hydrogel behavior for constituent orientation prediction. This approach provides an initial but robust framework to model scaffold anisotropy, enabling optimization of the extrusion process while maintaining computational feasibility
Development and validation of a thermal desorption method based on Py-GC-HRMS using in-house reference materials to quantify a set of additives in polypropylene
No full textInternational audienceBackgroundPlastic additives, such as plasticizers, flame retardants, and UV stabilizers, significantly enhance polymer properties but pose health and environmental risks due to their potential migration into food products. Current quantification methods commonly employ solvent extraction, which carries environmental and toxicity issues, as well as contamination issues. This study addresses the critical need for direct quantification of additives within plastic, using more sustainable, solvent-free, analytical methods.ResultsA thermal desorption technique combined with pyrolysis-gas chromatography-high resolution mass spectrometry (TD-GC-HRMS) is described to accurately quantify additives in food packaging. This method demonstrated excellent linearity (R2 > 0.99) within the concentration range of 0.01% to 0.2% w/w for additives including plasticizers (ATBC, BBP, DEHA, DEHP), flame retardants (TCEP, TDCIPP), and UV stabilizers (UV-326, UV-327). Limits of quantification ranged from 0.01% to 0.022% w/w, establishing robust analytical sensitivity. Method validation through an accuracy profile confirmed high reliability, with most additives exhibiting recovery rates above 97% in the first thermal desorption. Application to polypropylene food packaging samples revealed the presence of targeted additives below quantifiable levels, alongside other hazardous substances not regulated by current standards.SignificanceThe developed TD-GC-HRMS method provides a rapid, solvent-free, and reliable alternative for quantifying plastic additives in food packaging, significantly reducing environmental impact and operator exposure to hazardous chemicals
Phytochemical Profile, Genotoxicity, and In Silico Toxicity Assessment, Antioxidant, and Neuroprotective Effects of Clinopodium nepeta Essential Oil: Inhibition of Acetylcholinesterase, Butyrylcholinesterase, and Monoamine Oxidase
No full textInternational audienceThe aim of this study was to evaluate the chemical composition, genotoxicity, in silico predicted toxicity, antioxidant activity, and neuroprotective potential of essential oil (EO) extracted from the aromatic and medicinal plant Clinopodium nepeta , native to eastern Morocco. Chemical composition was assessed by gas chromatography‐mass spectrometry, revealing the presence of 19 compounds, the main ones being neoisomenthol (29.66%), dihydrocarvone (11.07%), and pulegone (9.4%). Infrared spectra obtained by the attenuated total reflection–Fourier‐transform infrared technique showed remarkable similarities with typical oxygenated monoterpene profiles, confirming the predominance of these compounds among the main constituents of the EO. In silico genotoxicity and predicted toxicity assessments indicated the absence of genotoxicity for this EO, suggesting its safe use. The antioxidant activity of the EO was assessed using three different methods. The neuroprotective potential of this EO was evaluated through its ability to inhibit key enzymes involved in neurodegenerative processes. The EO demonstrated significant inhibitory activity against acetylcholinesterase with an IC 50 of 31.88 ± 2.23 µg/mL, butyrylcholinesterase with an IC 50 of 29.90 ± 2.99 µg/mL, and monoamine oxidase with an IC 50 of 12.92 ± 1.22 µg/mL. These results highlight the potential applications of C. nepeta EO in pharmaceutical development, particularly for neurological conditions
Understanding the effect of tailored heat treatment on Zr-modified Al7075 fabricated by laser powder bed fusion
No full textInternational audienceDespite high-strength aluminium alloys now being widely processed by laser powder bed fusion (L-PBF), a specifically designed heat treatment (HT) for L-PBF Al7075 has yet to be identified and the microstructural features responsible for strengthening remain to be fully understood. In this study, fully dense Al7075+1.8%Zr was processed without hot cracking. High temperature heat treatments between 350°C and 525°C were adopted, attaining the highest hardness (162HV) at 425°C followed by an artificial ageing (AA). This heat treatment produced a yield strength of 515 MPa and an elongation at fracture of 12%. To understand the effect of this tailored low-temperature HT, comparisons were made with a classical T6 HT (1 h at 470°C followed by AA). Transmission electron microscopy analyses revealed a higher volume fraction of secondary precipitates with the 425°C HT than with the 470°C HT. These hardening precipitates were quantified as the main contributor to strengthening, accounting for 207 MPa. The 425°C HT prevented the over-ageing Zr precipitates generated by the 470°C HT, while inhibiting recrystallization. precipitates played a minor role in the tensile properties as they were nearly absent from the microstructure due to the excessive evaporation of Mg and Zn during L-PBF