Dependence of aerosol-borne influenza A virus infectivity on relative humidity and aerosol composition.

We describe a novel biosafety aerosol chamber equipped with state-of-the-art instrumentation for bubble-bursting aerosol generation, size distribution measurement, and condensation-growth collection to minimize sampling artifacts when measuring virus infectivity in aerosol particles. Using this facility, we investigated the effect of relative humidity (RH) in very clean air without trace gases (except ∼400 ppm CO) on the preservation of influenza A virus (IAV) infectivity in saline aerosol particles. We characterized infectivity in terms of 99%-inactivation time, , a metric we consider most relevant to airborne virus transmission.

Predicted Concentrations and Optical Properties of Brown Carbon from Biomass Burning over Europe.

Black carbon (BC) and brown carbon (BrC) are light-absorbing carbonaceous aerosol components that can contribute to radiative forcing and thus affect the climate. In this study, we focus on the modification of aerosol optical properties associated with BrC emissions from biomass burning. BrC is simulated with the introduction of three new species in the three-dimensional chemical transport model PMCAMx-SR, two primary-absorbing (inert and reactive BrC) species, and one "photobleached" BrC species.

Calibration and Inter-Unit Consistency Assessment of an Electrochemical Sensor System Using Machine Learning.

This paper addresses the challenges of calibrating low-cost electrochemical sensor systems for air quality monitoring. The proliferation of pollutants in the atmosphere necessitates efficient monitoring systems, and low-cost sensors offer a promising solution. However, issues such as drift, cross-sensitivity, and inter-unit consistency have raised concerns about their accuracy and reliability.

The effect of functional groups on the glass transition temperature of atmospheric organic compounds: a molecular dynamics study.

Organic compounds constitute a substantial part of atmospheric particulate matter not only in terms of mass concentration but also in terms of distinct functional groups. The glass transition temperature provides an indirect way to investigate the phase state of the organic compounds, playing a crucial role in understanding their behavior and influence on aerosol processes. Molecular dynamics (MD) simulations were implemented here to predict the glass transition temperature () of atmospherically relevant organic compounds as well as the influence of their functional groups and length of their carbon chain.