[1] Measurements of gaseous and particulate reactive nitrogen and sulfur species, as well as other chemical species, were made using the P-3B and DC-8 aircraft over the western Pacific during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) experiment, conducted between February and April 2001. These measurements provide a good opportunity to study the extent to which anthropogenic NO x and SO 2 emitted over the East Asian countries remain as NO y and SO x (=SO 2 + nssSO 4 2À) in the form of gas or fine particles when an air mass is transported into the western Pacific region. In this paper a method to estimate transport efficiencies, e(NO y ) and e(SO x ), in an air mass that has experienced multiple injection, mixing, and loss processes is described. In this analysis, CO and CO 2 are used as passive tracers of transport, and the emission inventories of CO, CO 2 , NO x , and SO 2 over the East Asia region are used. Results from the P-3B presented in this study indicate that 20-40% and 15% of NO x emitted over the northeastern part of China remained as NO y over the western Pacific in the boundary layer (BL) and free troposphere (FT), respectively. In the FT, PAN is found to have been the dominant form of NO y , while only 0.5% of emitted NO x remained as NO x . The transport efficiency of SO x is estimated to have been 25-45% and 15-20% in the BL and FT, respectively. Median values of the nssSO 4 2À /SO x ratio are 0.4-0.6 both in the BL and FT, however large variability is found in the FT. These results are generally consistent with those derived using DC-8 data. The results obtained in this study indicate that more than half of NO y and SO x were lost over the continent and that the vertical transport from the BL to FT further reduced their amounts by a factor of 2, likely due to wet removal. Budgets of NO y and SO x were also studied for air masses, which we sampled during TRACE-P and the flux out from the continent in these cases is estimated to be 20% of the emissions. Flux in the BL and FT is found to have a similar contribution.

Total reactive nitrogen (NOy) in the Arctic lower stratosphere was measured from the NASA DC‐8 aircraft during the SAGE III Ozone Loss and Validation Experiment (SOLVE) in the winter of 1999/2000. NOy‐N2O correlations obtained at altitudes of 10–12.5 km in December 1999 and January 2000 are comparable to the reported reference correlation established using the MkIV balloon measurements made during SOLVE prior to the onset of denitrification. Between late February and mid‐March, NOy values obtained from the DC‐8 were systematically higher than those observed in December and January by up to 1 part per billion by volume, although a compact correlation between NOy and N2O was maintained. Greater increases in NOy were generally observed in air masses with lower N2O values. The daily minimum temperatures at 450–500 K potential temperature (∼20–22 km) in the Arctic fell below the ice saturation temperature between late December and mid‐January. Correspondingly, intense denitrification and nitrified air masses were observed from the ER‐2 at 17–21 km and below 18 km, respectively, in January and March. The increases in NOy observed from the DC‐8 in late February/March indicate that influence from nitrification extended as low as 10–12.5 km over a wide area by that time. We show in this paper that the vertical structure of the temperature field during the winter was a critical factor in determining the vertical extent of the NOy redistribution. Results from the Reactive Processes Ruling the Ozone Budget in the Stratosphere (REPROBUS) three‐dimensional chemistry transport model, which reproduced the observed general features only when the NOy redistribution process is included, are also presented.

The conformation of tridecapeptide α‐mating factor from yeast Saccharomyces cerevisiae in aqueous solution was analyzed, in comparison with those of active analog and inactive analog peptides. 270‐MHz 1H‐NMR spectra of these peptides were observed and the spectral patterns of main‐chain N‐H proton resonances were classified into three groups, α‐mating factor and Trp1‐bearing active peptides belong to the group A1, active des‐Trp1‐peptides belong to the group A2 while the peptides of group B are inactive. The main‐chain N‐H proton resonances of the groups A1 and A2 and side‐chain N‐H proton resonances were all assigned to individual residues. The 13C‐NMR analysis of α‐mating factor indicates that the Lys7‐Pro8 and Gln10‐Pro11 peptide bonds exclusively take the trans form. From the temperature and pH dependences of chemical shifts and Gd(III)‐induced relaxation enhancements of amide proton resonances, α‐mating factor is found to take partly a folded conformation in aqueous solution, with an α‐helical form in the N‐terminal domain and two β‐turn forms in the central and C‐terminal domain. The pH dependence of fluorescence intensity indicates that, in this folded conformation, the C‐terminal carboxylate group lies close to the N‐terminal domain. The presence of the folded form in the N‐terminal domain and the β‐turn form in the central domain correlates with the biological activity of α‐mating factor and analog peptides. However, the folded conformation of α‐mating factor is in equilibrium with predominantly unordered form, as found from the circular dichroism and NMR analyses. The N‐H proton and C‐α proton resonances of free α‐mating factor as assigned in the present study allow the transferred nuclear Overhauser enhancement (NOE) analysis of the membrane‐bound conformation that is more directly related with the activity.

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