This study investigated the relationship between water-soluble organic compounds of ambient particulate matter (PM) and cellular redox activity collected from May 28 to June 20 of 2016 at the west coastal site in the Republic of Korea during the KORea-US Air Quality (KORUS-AQ) campaign. Automatic four-hour integrated samples operated at a flow rate of 92 L per minute for the analysis of organic...

Carbonaceous compounds comprise a substantial fraction of atmospheric particulate matter (PM). Particulate organic material can be emitted directly into the atmosphere or formed in the atmosphere when the oxidation products of certain volatile organic compounds condense. Such products have lower volatilities than their parent molecules as a result of the fact that adding oxygen and/or nitrogen ...

The yields of the tropical rivers of Southeast Asia supply large quantities of carbon to the ocean. The origin and dynamics of particulate organic matter were studied in the Houay Xon River catchment located in northern Laos during the first erosive flood of the rainy season in May 2012. This cultivated catchment is equipped with three successive gauging stations draining areas ranging between ...

I propose to compare two paleoproductivity indicators recording “opposite” aspects of primary productivity, organic carbon production at the sea surface (coccolith Sr/Ca ratios) and its consumption on the sea floor (benthic foraminiferal accumulation rates, BFAR). Calcification and growth rates of coccolithophores can be linked to particulate organic matter production in the photic zone (Balch ...

Biological degradation of terrestrially derived macromolecules including lignin and cellulose has been shown to produce a large number of environmentally relevant phenolic compounds. It has demonstrated that extracellular superoxide (O2 ) is produced by heterotrophic bacteria that are common in lakes, soil, hydrothermal vents, marine sediments, estuaries and oceans. Rates of superoxide producti...

Ammonium nitrate and several organic compounds such as dicarboxylic acids (e.g. succinic acid, glutaric acid), some Polycyclic Aromatic Hydrocarbon (PAHs) or some n-alkanes are semi-volatile. The transition of these compounds between the gas and particulate phase may significantly change the aerosol particles radiative properties, the heterogeneous chemical properties, and, naturally, the total...

As part of the Western Arctic Shelf–Basin Interactions (SBI) project, the production and fate of organic carbon and nitrogen from the Chukchi and Beaufort Sea shelves were investigated during spring (5 May–15 June) and summer (15 July–25 August) cruises in 2002. Seasonal observations of suspended particulate organic carbon (POC) and nitrogen (PON) and large-particle (453mm) size class suggest t...

Cold-water corals release organic matter, in particular mucus, but its role in the ecological functioning of reef ecosystems is still poorly understood. The present study investigates the planktonic microbial degradation of mucus released by Lophelia pertusa colonies from Tisler Reef, Skagerrak. Results are compared to the degradation of dissolved and particulate organic substrates, including t...

Phosphorus (P) regeneration and transformation in the oceanic water column and in marine sediments depends on the chemical nature of the sinking particulate P pool. For the first time, we have characterized the molecular composition of this pool, in various oceanic settings and water depths, using P nuclear magnetic resonance (NMR) spectroscopy. Both inorganic P (orthophosphate, pyrophosphate, ...

The relationship of bronchitic symptoms to ambient particulate matter and to particulate elemental and organic carbon (OC), nitrogen dioxide (NO2), and other gaseous pollutants was examined in a cohort of children with asthma in 12 Southern California communities. Symptoms, assessed yearly by questionnaire from 1996 to 1999, were associated with the yearly variability of particulate matter with...