1.Effects of trajectory wind direction on ion concentration of PM10.
Biomedical and Environmental Sciences 2006;19(4):262-267
OBJECTIVETo study the characterization apportionment of main ion concentrations of PM10 under the influence of trajectory wind direction in London.
METHODSPM10 samples from 1 May 1995 to 30 October 1995 of Oxford Street of Central London were collected, the metals and anions of which were measured using atomic absorption spectrometry (AAS) and ion chromatography (IC). Composite trajectories representative of the air mass arriving in London at the same period were calculated based on basic routine back trajectories from the British Atmospheric Data Centre (BADC).
RESULTSConcentration apportionments of main ions were similar when the trajectory was plotted back at 6 h, 12 h, and 24 h, some were obviously different. Mg, Ba, Pb, and Cu had similar peak apportionments at the area 180 degrees-320 degrees, but Zn and Ni at the area of 90 degrees-270 degrees, NO3 and SO4(2-) at the area of 100 degrees-220 degrees. Cl- concentration peak apportionment was at the area of 220 degrees-300 degrees, which showed that Cl- mainly came from the North Sea.
CONCLUSIONTrajectory wind direction has important effect on ion concentration apportionment of PM10 in London. The ions have similar concentration peak apportionments or their correlation coefficients are statistically significant.
Air Pollutants ; analysis ; chemistry ; Anions ; analysis ; Cations ; analysis ; Environmental Monitoring ; London ; Particle Size ; Time Factors ; Wind
2.Facile synthesis of insulin fusion derivatives through sortase A ligation.
Maria M DISOTUAR ; Jake A SMITH ; Jinze LI ; Steve ALAM ; Nai-Pin LIN ; Danny Hung-Chieh CHOU
Acta Pharmaceutica Sinica B 2021;11(9):2719-2725
Insulin derivatives such as insulin detemir and insulin degludec are U.S. Food and Drug Administration (FDA)-approved long-acting insulin currently used by millions of people with diabetes. These derivatives are modified in C-terminal B29 lysine to retain insulin bioactivity. New and efficient methods for facile synthesis of insulin derivatives may lead to new discovery of therapeutic insulin. Herein, we report a new method using sortase A (SrtA)-mediated ligation for the synthesis of insulin derivatives with high efficiency and functional group tolerance in the C-terminal B chain. This new insulin molecule (Ins-SA) with an SrtA-recognizing motif can be conjugated to diverse groups with N-terminal oligoglycines to generate new insulin derivatives. We further demonstrated that a new insulin derivative synthesized by this SrtA-mediated ligation shows strong cellular and