Publications by authors named "A Prevot"
Oxidative potential (OP) is increasingly recognized as a more health-relevant metric than particulate matter (PM) mass concentration because of its response to varying chemical compositions. Given the limited research on the OP of complex combustion aerosols, the effects of aging processes on their OP remain underexplored. We used online instruments to track the evolution of OP [via dithiothreitol (DTT) assays] during the aging of wood burning and coal combustion emissions by hydroxyl-radical-driven photooxidation and dark ozonolysis.
View Article and Find Full Text PDFCarbonaceous aerosols (CA), composed of black carbon (BC) and organic matter (OM), significantly impact the climate. Light absorption properties of CA, particularly of BC and brown carbon (BrC), are crucial due to their contribution to global and regional warming. We present the absorption properties of BC (b) and BrC (b) inferred using Aethalometer data from 44 European sites covering different environments (traffic (TR), urban (UB), suburban (SUB), regional background (RB) and mountain (M)).
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- Head and neck squamous cell carcinoma (HNSCC) shows significant genetic diversity within tumors, complicating targeted treatment approaches and making traditional imaging ineffective for detecting minimal residual disease (MRD).
- A study of 41 patients with resectable HNSCC found that circulating tumor DNA (ctDNA) can serve as a biomarker for assessing tumor heterogeneity and MRD, with notable detection rates at surgery and recurrence.
- The presence of ctDNA shortly after surgery correlated with disease recurrence, providing an early warning about potential relapse, thus supporting its role in post-operative monitoring and precision medicine strategies.
Biomass burning (BB) is a major source of aerosols and black carbon, thereby exerting an important impact on climate and air quality. Levoglucosan is the most well-recognized organic marker compound of BB and has been used to quantitatively assess BB's contribution to ambient aerosols. However, little is known about levoglucosan's evaporation under atmospheric conditions, primarily due to the uncertainty of its effective saturation vapor concentration (*) and its unknown activity coefficient (γ), in the complex BB emission matrix.
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- VOCs play a crucial role in forming secondary organic aerosol (SOA), but understanding this process, particularly regarding oxygenated VOCs (OVOCs) and SOA composition, remains complex.
- In summer 2016, researchers used advanced mass spectrometry techniques in Zurich to analyze VOCs and their oxidation products, identifying five sources of these compounds, primarily from traffic and local emissions, as well as various atmospheric oxidation processes.
- The findings revealed that both gas phase and aerosol phase OVOCs exhibited similar patterns and characteristics, particularly indicating that biogenic contributions dominated the SOA and that there were distinct differences in chemical behavior between day and night.