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[1] We study seismic velocity and attenuation structures in the top 400 km of the Earth’s inner core based on modeling of differential traveltimes, amplitude ratios, and waveforms of the PKiKP-PKIKP phases observed at the epicentral distance range of 120 –141 and the PKPbc-PKIKP phases observed at the distance range of 146 –160 along equatorial paths. Our(More)
We investigate the attenuation structure of the Earth's inner core and its relationship to the velocity structure globally and along various sampling directions, by studying the amplitude ratios and the differential travel times of the PKiKP–PKIKP and PKPbc– PKIKP phases. Our observations reveal that the amplitude ratios of these core phases, like the(More)
Abundant ions corresponding to the gas-phase cleavage of the Asp-Pro and Asp-Xxx bonds of peptides in the process of matrix-assisted laser desorption were observed using a time-of-flight mass spectrometer equipped with both linear and reflector mass analyzers. Peptides containing the N-terminal sequence, Asp-Pro ... from an endoproteinase Asp-N digest(More)
Matrix-assisted laser desorption-ionization (MALDI)-postsource decay (PSD) was used to differentiate glycoprotein-released N-linked oligosaccharide isomers directly from aliquots of glycosidase digests and peak fractions collected from high-pH anion exchange chromatography (HPAEC) with minimal sample handling and material. With the implementation of(More)
[1] We report complex seismic anisotropy in the top 80 km of the Earth’s inner core beneath Africa. The anisotropy in the top 80 km of the inner core is constrained using differential travel times, amplitude ratios, and waveforms of the PKiKP-PKIKP phases sampling Africa along various directions. The differential PKiKP-PKIKP time residuals (relative to the(More)
The utility of matrix-assisted laser desorption time-of-flight (MALD-TOF) mass spectrometry for the analysis of recombinant glycopeptides is discussed and compared to information which may be obtained by fast atom bombardment mass spectrometry (FABMS) and tandem mass spectrometry (MS/MS). MALD-TOF appears to be 10-100 times more sensitive than FAB MS for(More)
A comparative method for the quantitative analysis of the ratio of oxonium fragment (reporter) ions derived from sialic acid and N-acetylhexosamine residues on a large intact glycoprotein, the B domain of recombinant human factor VIII (rhFVIII), was developed. The method utilized liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS) on(More)
The fluorescent emission kinetics of spinach subchloroplast Photosystems I and II particles have been studied on a picosecond time scale. Using picosecond laser pulses and an optical Kerr gate, the fluorescent decay times are measured to be 60 plus or minus 10 ps, and 200 plus or minus 20 ps for Photosystems I and II, respectively. The quantum yields are(More)
The types, extent, and overall distribution of peptide fragmentation produced by matrix-assisted laser desorption-ionization-postsource decay (MALDI-PSD) on a reflector time-of-flight mass spectrometer were compared with those obtained from high and low energy collision-induced dissociation (CID) on a four-sector mass spectrometer and from liquid secondary(More)