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The air quality of South Korea was the focus of the NASA/NIER KORean -United States Air Quality (KORUS-AQ) mission of 2016. KORUS-AQ was planned for the period after the spring peak in outbreaks of Asian dust. Regardless of this strategic planning, quantifiable dust was still observed via instrumentation on the NASA DC-8 in early May. A novel analysis of supermicron dust and associated supermicron ionic relationships was completed using two size dependent instruments. This supermicron dust provided surface area for heterogeneous chemistry between CaCO 3 , the gases HNO 3 , NO 2 , and SO 2 , and particulate (NH 4) 2 SO 4. Uptake of the pollutant gases is greatly enhanced by formation of an aqueous layer on the surface of the dust particles. More water is attracted to particles where uptake of HNO 3 has replaced surface CaCO 3 with Ca(NO 3) 2 generating a dynamic aqueous layer on the dust particle. We propose that particulate (NH 4) 2 SO 4 coagulated with dust to form (NH 4) 2 Ca(SO 4) 2 on the particle surface, which rapidly formed CaSO 4 and NH 4 + in a Ca(NO 3) 2 facilitated aqueous layer. A conceptual model is proposed to explain these dust uptake chemical processes. We define the nanoequivalent concentration of supermicron SO 4 2− plus NO 3 − over the nanoequivalent concentration of supermicron NH 4 + plus Ca2+ as the Dust Pollution Index (DPI), used to quantify the extent to which carbonate dust has been modified. DPI values range from 0 (pure dust) to 1 (completely reacted); thus, it represents the conversion of CaCO 3 into secondary salts. This mechanism should be used to better predict chemical dynamics in atmospheric models while also helping to further explain the importance of dust and secondary coating on cloud formation processes and dust optical properties. Air masses containing dust that traversed industrial China while mixing with polluted southern air had significantly higher DPI values (average = 0.82, 1σ = 0.10) compared to air masses that limited interaction with such pollution (average = 0.51, 1σ = 0.13). • Supermicron dust collected during KORUS-AQ was chemically modified during transport, taking up HNO 3 and (NH 4) 2 SO 4. • (NH 4) 2 SO 4 particles coagulated with dust while gas phase HNO 3 reacted and modified the dust to be hygroscopic. • A conceptual model and the Dust Pollution Index are proposed to explain these uptake mechanisms. [ABSTRACT FROM AUTHOR]

Nitric acid (HNO3) was reduced in a flow tube by volatile organic carbon compounds (VOCs) generated from engine oil vapor. The primary reaction product was believed to be HONO. The reaction was not enhanced when Teflon® Raschig rings were added to the flow tube to increase surface area, thereby showing the reaction to be homogeneous under the conditions studied. The HONO formation observed ranged between 0.1 and 0.6 ppb h−1, with a mean of 0.3 ± 0.1 ppb h−1, for typical HNO3 concentrations of 4–5 ppb and estimated concentrations of the reactive components in the engine oil vapor between 200 and 300 ppt. The observations in this study compare well to a recently published field study conducted in Houston that observed average formation rates of 0.6 ± 0.3 ppb h−1. Water vapor was found to decrease the HONO formation rate by ∼0.1 ppb h−1 for every 1% increase in the water mixing ratio. [ABSTRACT FROM AUTHOR]

Abstract: The number of patients in need of a liver transplant vastly exceeds the number of available organs; the demand worldwide for organs leads to increased waiting times and mortality of patients on the waiting list. The aim of our study was to assess the psychosocial well-being of transplant candidates and their need for psychosocial counselling. Methods: Sixty-nine liver transplant candidates were asked about their psychosocial well-being, quality of life, spirituality, and need for counselling assessed by interview and questionnaire (HADS-D, FLZ, LOT, SOC, SF-36, SBI-15R) during the initial evaluation procedure for organ transplantation as well as 3 and 6 months after listing. Results: Candidates for a liver transplant exhibited a significant limitation in the levels of their quality of life and psychological well-being, compared with the community normal samples. They showed significantly higher levels of anxiety, but lower levels of spirituality. Almost half of the candidates (47%) expressed a need for counselling during the evaluation procedure. Patients with advanced diseases reported a lower need. Age and the personality-related “Sense of Coherence” correlated negatively with need for counselling. On the waiting list, psychosocial parameters and functions remained largely stable; the need for counselling decreased significantly. Conclusions: There is a relevant need for psychosocial counselling during the process of liver transplant evaluation. Need for counselling is associated with personality and age, as well as with somatic parameters. [Copyright &y& Elsevier]