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Organic aerosol (OA) from natural or anthropogenic origin can be directly emitted into the atmosphere (primary organic aerosols, POA) or formed by secondary processes via the oxidation of volatile organic compounds (VOC). However, the formation pathways and their chemical composition of these secondary organic aerosols (SOA), which may contribute up to 90% of the OA mass, are not well understood to date, which is problematic due to the relevance of SOA on climate. To address this issue, this study uses a tracer-based approach to identify and quantify the contribution of different anthropogenic/biogenic VOCs precursors to the SOA formation. To do so, we combine experiments in a large scale atmospheric simulations chamber, CESAM (which means Multiphase Atmospheric Experimental Simulation Chamber), and field measurements during the ACROSS (Atmospheric ChemistRy Of the Suburban foreSt) campaign conducted in the Paris area in summer 2022. This approach provides both a mechanistic study of the oxidation of targeted VOCs in simulated and controlled rural/urban atmospheres and the identification of targeted tracers in the real atmosphere, to quantify their concentrations in ambient air.The ACROSS dataset consists in atmospheric samples of submicron aerosols collected twice a day (day and night) in the urban area of Paris and the Rambouillet forest on the south-west of Paris, as well as samples collected onboard the Safire ATR-42 research aircraft on low-level flights targeting the evolution and dilution of the Paris urban plume. The CESAM chamber dataset consists in samples of SOA generated by the OH oxidation of toluene/ m-xylene in various conditions.Filters are analyzed to provide with the chemical composition at the molecular scale by SFE-GC-MS (Supercritical Fluid Extraction Gas Chromatography- Mass Spectrometry) and UPLC-QTOF-MS (Ultra Performance Liquid Chromatography Time of Flight Mass Spectrometry). The organic mass and chemical speciation are obtained by aerosol mass spectrometry and the organic carbon (OC) concentrations by thermal-optical analysis.The first results of the ambient samples of Paris revealed that the OC concentration varied between 0.69 ± 0.07 and 9.48 ± 0.51 µgC/m3, which correspond to the 28% and 53% of the total mass of the submicron aerosols, for background and polluted (fire) conditions, respectively. These diverse conditions are favorable to trace the compounds identified during the simulation chamber experiments, such as benzoic acid, succinic acid, and 2-methyl-4-nitrophenol. These attempts will be presented and discussed in order to determine the contribution of specific precursors to SOA formation.

This study draws on lexical semantics to support a discourse analysis perspective (Gosselin 2018; Galatanu 2018). It examines the use of the French noun artère ‘artery’ (a common word from the lexicon (Maingueneau 2021)) to refer to a street-like entity (street, avenue, boulevard, etc.). The empirical investigation was based on an analysis of 150 utterances (extracted from three full-text databases). On the one hand, the study shows that selecting artère to refer to a street-like entity is a discursive strategy targeting a significant representation of the referent, especially when this referent is not a prototypical urban street. On the other hand, it supports the idea that this discursive choice strongly relies on the lexical signification of artère (Bertin 2018).

This study deals with meaning construction in idiomatic phrases (locutions figées/figements). We focus on three French idioms involving the word cœur (à contrecœur, de bon cœur, de tout cœur). To begin, we give a brief account of idiomaticity’s typical criteria, insisting on the common idea that idioms are semantically opaque (non-compositional): their meanings are not a combination of literal meanings (Gross 1996). We argue that another point of view is productive. Indeed, using the notion of “holistic compositionality” (Gosselin 2013), we investigate the way meaning may arise from the combination of words’ abstract semantic contributions (compositionality principle) and take shape contextually (contextuality principle). The primary goal of the study is to analyze the meaning of à contrecœur, de bon cœur, de tout cœur using this approach – which happens to be more accurate than the literal meaning combination approach. To achieve this goal for each of these three idioms: (1) we examine a sample of 200 utterances (and the contexts in which they occur) coming from a large data-source (frWaC) and (2) we take advantage of previous semantic descriptions of cœur (Bertin 2018, 2019), contre (Amiot & De Mulder 2003; Paillard 2003), bon (Katz 1964) and tout (Bat-Zeev Shyldkrot 1995). These two methodological tools shed light on the operation of the semantic mechanism and emphasize the relevance of the “holistic compositionality” approach when applied to idioms’ meaning construction.

From January 2011 to March 2018, 26 patients aged from 20 to 80 years old reported being sick in France after eating sea figs of the genus Microcosmus. The patients had symptoms evoking a cerebellar syndrome: blurred or double vision, ataxia and dizziness, asthenia, headache, muscle cramps, paresthesia and digestive disorders (nausea, vomiting and diarrhea). Three of the 18 food poisoning events recorded by the Poison Control Center in Marseille and involving four patients were further investigated as the meal leftovers were collected and analyzed. A previous study ruled out the presence of the regulated lipophilic marine toxins after high-resolution mass spectrometry, but further analyses were required to look for hydrophilic cyanotoxins. The sea fig leftovers from food poisoning case Numbers 1 (January 2011), 6 (December 2012) and 17 (March 2018) of this published case series were analyzed by hydrophilic interaction liquid chromatography coupled to low- and high-resolution mass spectrometry to investigate the presence of hydrophilic cyanotoxins. The sea fig samples showed anatoxin-a (ATX-a) concentrations ranging from 193.7 to 1240.2 &micro, g/kg. The sea fig control sample analyzed was also contaminated with ATX-a but in a much smaller concentration (22.5 &micro, g/kg). To the best of our knowledge, this is the first report of human food poisoning involving ATX-a as the possible causative toxin where the cyanotoxin could be unequivocally identified.

International audience; In the field of mass sensing, there is an ever growing interest in the development of ultrasensitive MEMS devices for agro-food, environment, safety or health. Within this context, mode localization in an array of coupled resonators has been studied and implemented for a fewyears due to its high sensitivity to mass perturbation. However, this phenomenon requires a few conditions often hard to gather mainly due to microfabrication flaws and the devices geometry. In this paper, we present a device able to generate mode localization using a single piezoelectric resonator connected in closed loop to a hardware that simulates in real time the other resonators. Its main strengths are its full tunability and adaptibility to the geometry of the resonators.