English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Recent epidemiological evidence supports the hypothesis that health effectsfrom inhalation of ambient particulate matter (PM) are governed by more thanjust the mass of PM inhaled. Both specific chemical components and sourceshave been identified as important contributors to mortality and hospitaladmissions, even when these end points are unrelated to PM mass. Sources maycause adverse health effects via their ability to produce reactive oxygenspecies in the body, possibly due to the transition metal content of the PM.Our goal is to quantify the oxidative potential of ambient particle sourcescollected during two seasons in Fresno, CA, using the dithiothreitol (DTT)assay. We collected PM from different sources or source combinations intodifferent ChemVol (CV) samplers in real time using a novel source-orientedsampling technique based on single-particle mass spectrometry. We segregatedthe particles from each source-oriented mixture into two size fractions –ultrafine Dp ≤ 0.17 μm) and submicron fine(0.17 μm ≤ Dp ≤ 1.0 μm) – and measuredmetals and the rate of DTT loss in each PM extract. We find that themass-normalized oxidative potential of different sources varies by up to afactor of 8 and that submicron fine PM typically has a larger mass-normalizedoxidative potential than ultrafine PM from the same source. Vehicularemissions, regional source mix, commute hours, daytime mixed layer, andnighttime inversion sources exhibit the highest mass-normalized oxidativepotential. When we apportion DTT activity for total PM sampled to specificchemical compounds, soluble copper accounts for roughly 50% of totalair-volume-normalized oxidative potential, soluble manganese accounts for20%, and other unknown species, likely including quinones and otherorganics, account for 30%. During nighttime, soluble copper andmanganese largely explain the oxidative potential of PM, while daytime has alarger contribution from unknown (likely organic) species

Oxidant production from source-oriented particulate matter – Part 1: Oxidative potential using the dithiothreitol (DTT) assay