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We simulate nitrogen deposition over the US in 2006-2008 by using the GEOS-Chem global chemical transport model at 1/2deg; x 2/3° horizontal resolution over North America and adjacent oceans. US emissions of NOx and NH3 in the model are 6.7 and 2.9 Tg Na-1 respectively, including a 20% natural contribution for each. Ammonia emissions are a factor of 3 lower in winter than summer, providing a good match to US network observations of NHx (≡NH3 gas + ammonium aerosol) and ammonium wet deposition fluxes. Model comparisons to observed deposition fluxes and surface air concentrations of oxidized nitrogen species (NOy) show overall good agreement but excessive wintertime HNO3 production over the US Midwest and Northeast. This suggests a model overestimate N2O5 hydrolysis in aerosols, and a possible factor is inhibition by aerosol nitrate. Model results indicate a total nitrogen deposition flux of 6.5 TgNa-1 over the contiguous US, including 4.2 as NOy and 2.3 as NHx. Domestic anthropogenic, foreign anthropogenic, and natural sources contribute respectively 78 %, 6 %, and 16% of total nitrogen deposition over the contiguous US in the model. The domestic anthropogenic contribution generally exceeds 70% in the east and in populated areas of the west, and is typically 50-70% in remote areas of the west. Total nitrogen deposition in the model exceeds 10 kgNha-1 a-1 over 35% of the contiguous US. [ABSTRACT FROM AUTHOR]

In 1965, the specialty of paediatric nephrology was in its infancy. Following the development of a landmark collaborative research study, the International Study of Kidney Disease in Childhood in the mid-1960s, the first specialist societies were formed: the European Society of Pediatric Nephrology in 1967 and the American Society of Pediatric Nephrology in 1969. The extraordinary improvements in care delivered to children with kidney disease over the past 50 years are too broad to cover in any one paper. They traverse the spectrum of diagnosis, classification, therapeutics, social well-being and transition to adult care. We have selected four case scenarios to highlight these changes in key areas of paediatric nephrology: post-streptococcal glomerulonephritis, nephrotic syndrome, haemolytic uraemic syndrome and neonatal dialysis and childhood transplantation., (© 2014 The Authors. Journal of Paediatrics and Child Health © 2014 Paediatrics and Child Health Division (Royal Australasian College of Physicians).)