Conjugating time and frequency: hemispheric specialization, acoustic uncertainty, and the mustached bat.

A prominent hypothesis of hemispheric specialization for human speech and music states that the left and right auditory cortices (ACs) are respectively specialized for precise calculation of two canonically-conjugate variables: time and frequency. This spectral-temporal asymmetry does not account for sex, brain-volume, or handedness, and is in opposition to closed-system hypotheses that restrict this asymmetry to humans. Mustached bats have smaller brains, but greater ethological pressures to develop such a spectral-temporal asymmetry, than humans. Using the Heisenberg-Gabor Limit (i.e., the mathematical basis of the spectral-temporal asymmetry) to frame mustached bat literature, we show that recent findings in bat AC (1) support the notion that hemispheric specialization for speech and music is based on hemispheric differences in temporal and spectral resolution, (2) discredit closed-system, handedness, and brain-volume theories, (3) underscore the importance of sex differences, and (4) provide new avenues for phonological research.

A new computer program (GlycoX) to determine simultaneously the glycosylation sites and oligosaccharide heterogeneity of glycoproteins.

A new computer program, GlycoX, was developed to aid in the determination of the glycosylation sites and oligosaccharide heterogeneity in glycoproteins. After digestion with the nonspecific protease, each glycan at a specific glycosylation site contains a small peptide tag that identifies the location of the glycan. GlycoX was developed in MATLAB requiring the entry of the exact masses of the glycopeptide and the glycan spectra in the form of a mass-intensity table and taking advantage of the accurate mass capability of the mass analyzer, in this case a Fourier transform ion cyclotron resonance (FT ICR) mass spectrometer. This program computes not only the glycosylation site but also the composition of the glycans at each site. Several glycoproteins were used to determine the efficacy of GlycoX. These glycoproteins range from the simple, with one site of glycosylation, to the more complex, with multiple (three) sites of glycosylation. The results obtained using the computer program were the same as those determined manually. Model glycoproteins yielded the correct results, and new glycoproteins with unknown glycosylation were examined with the site of glycosylation and the corresponding glycans determined. Furthermore, other functions in GlycoX, including an auto-isotope filter to identify monoisotopic peaks and an oligosaccharide calculator to obtain the oligosaccharide composition, are demonstrated.