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We propose a new Fourier-transform spectroscopy technique based on the rotational Doppler effect. The technique offers an application for optical vortex frequency combs, where each frequency component carries a unique amount of orbital angular momentum (OAM). Here, we emulate a vortex comb using a tunable single frequency laser and a collection of spiral phase plates, generating up to 11 distinct OAM modes. Unlike in traditional Fourier-transform spectroscopy based on the Michelson interferometer (linear Doppler effect), the spectral resolution of vortex-comb spectroscopy is not limited by the mechanical scan distance of the instrument, but the instrument can be operated continuously without interruptions, leading to fast mode-resolved measurements. [ABSTRACT FROM AUTHOR]

The study investigated whether number magnitude can influence vocal responses. Participants produced either short or long version of the vowel [ɑ] (Experiment 1), or high or low-pitched version of that vowel (Experiment 2), according to the parity of a visually presented number. In addition to measuring reaction times (RT) of vocal responses, we measured the intensity, the fundamental frequency (f0) and the first and second formants of the vocalization. The RTs showed that the long and high-pitched vocal responses were associated with large numbers, while short and low-pitched vocal responses were associated with small numbers. It was also found that high-pitched vocalizations were mapped with the odd numbers, while the low-pitched vocalizations were mapped with the even numbers. Finally, large numbers increased the f0 values. The study shows systematic interactions between the processes that represent number magnitude and produce vocal responses. [ABSTRACT FROM AUTHOR]

Aim We studied whether available oxygen without induced mechanical stretch regulates the release of the biologically active B-type natriuretic peptide ( BNP) from Langendorff heart. Methods Rat hearts were isolated and perfused with a physiological Krebs-Henseleit solution at a constant hydrostatic pressure in Langendorff set-up. The basal O2 level of perfusate (24.4 ± 0.04 mg L−1) was gradually lowered to 3.0 ± 0.01 mg L−1 over 20 min using N2 gas ( n = 7). BNP and O2 level were measured from coronary flow. During control perfusions ( n = 5), the O2 concentration was kept at 26.6 ± 0.3 mg L−1. Results A low oxygen concentration in the perfusate was associated with a significant increase in BNP release ( F = 40.4, P < 0.001). Heart rate decreased when the oxygen concentration in the perfusate reached 9.1 ± 0.02 mg L−1 and continued to fall in lower oxygen concentrations ( F = 14.8 , P < 0.001). There was also a significant but inverse correlation between BNP and oxygen in the coronary flow ( R2 = 0.27, P < 0.001). Conclusion In the spontaneously beating Langendorff rat heart, a decreasing concentration of oxygen in the ingoing perfusion increased the secretion of BNP. The effect of oxygen was independent of mechanical stretch of the heart as it occurred even when the heart rate decreased but the pressure conditions remained constant. The difference in the oxygen capacitance of blood and Krebs-Henseleit solution appears to be a major factor affecting secretion of BNP, which is correlated with the oxygen tension of myocardial cells and affected both by the oxygen concentration and capacitance of solution perfusing the heart and by the coronary flow. [ABSTRACT FROM AUTHOR]