Search Results (2)

A semi-continuous monitoring system, a parallel plate wet denuder and particle into liquid sampler coupled with ion chromatography (PPWD-PILS-IC), was used to measure the hourly precursor gases and water-soluble inorganic ions in ambient particles smaller than 2.5 µm in diameter (PM_2.5) for investigating the thermodynamic equilibrium of aerosols using the ISORROPIA-II thermodynamic equilibrium model. The 24-h average PPWD-PILS-IC data showed very good agreement with the daily data of the manual 5 L/min porous-metal denuder sampler with R² ranging from 0.88 to 0.98 for inorganic ions (NH₄⁺, Na⁺, K⁺, NO₃⁻, SO₄²⁻, and Cl⁻) and 0.89 to 0.98 for precursor gases (NH₃, HNO₃, HONO, and SO₂) and slopes ranging from 0.94 to 1.17 for ions and 0.87 to 0.95 for gases, respectively. In addition, the predicted ISORROPIA-II results were in good agreement with the hourly observed data of the PPWD-PILS-IC system for SO₄²⁻ (R² = 0.99 and slope = 1.0) and NH₃ (R² = 0.97 and slope = 1.02). The correlation of the predicted results and observed data was further improved for NH₄⁺ and NO₃⁻ with the slope increasing from 0.90 to 0.96 and 0.95 to 1.09, respectively when the HNO₂ and NO₂⁻ were included in the total nitrate concentration (TN = [NO₃⁻] + [HNO₃] + [HONO] + [NO₂⁻]). The predicted HNO₃ data were comparable to the sum of the observed [HNO₃] and [HONO] indicating that HONO played an important role in the thermodynamic equilibrium of ambient PM_2.5 aerosols but has not been considered in the ISORROPIA-II thermodynamic equilibrium model. Full article

The peptidyl prolyl isomerases (PPI) of the cyclophilin type are distributed throughout human cells, including eight found solely in the nucleus. Nuclear cyclophilins are involved in complexes that regulate chromatin modification, transcription, and pre-mRNA splicing. This review collects what is known about the eight human nuclear cyclophilins: peptidyl prolyl isomerase H (PPIH), peptidyl prolyl isomerase E (PPIE), peptidyl prolyl isomerase-like 1 (PPIL1), peptidyl prolyl isomerase-like 2 (PPIL2), peptidyl prolyl isomerase-like 3 (PPIL3), peptidyl prolyl isomerase G (PPIG), spliceosome-associated protein CWC27 homolog (CWC27), and peptidyl prolyl isomerase domain and WD repeat-containing protein 1 (PPWD1). Each “spliceophilin” is evaluated in relation to the spliceosomal complex in which it has been studied, and current work studying the biological roles of these cyclophilins in the nucleus are discussed. The eight human splicing complexes available in the Protein Data Bank (PDB) are analyzed from the viewpoint of the human spliceophilins. Future directions in structural and cellular biology, and the importance of developing spliceophilin-specific inhibitors, are considered. Full article