Heart rate variability (HRV), which means variation of beat-to-beat interval, is a noninvasive way to evaluate ANS functions.
Pulse pressure variation (PPV), systolic pressure variation (SPV) and SVV were estimated manually by the variation of beat-to-beat PP, SP and SV, respectively.
Embryos treated with terfenadine showed a significant increase in the variation of heart beat interval.
Terfenadine-treated embryos showed variation of heart beat, from about 1 Hz to 2.5 Hz. (data not shown).
The STFT analysis illustrated the changes of heart rate time by time which was similar to poincare plot, indicating the ability of our program to determine the variation of heart beat frequency.
Variation of heart beat interval was significantly increased from 0.0615 ± 0.0107 in control embryos to 0.1857 ± 0.0627 in terfenadine treated embryos (p < 0.01), illustrating the increased variation of heartbeat by terfenadine in zebrafish embryos.
Then, last thing at night, he goes through every variation of how to beat the goalkeeper.
Variation of the wing beat may also occur, not just amongst different species, but even among individuals at different times.
For example, SDANN (standard deviation of the average NN interval calculated over 5-min intervals within the entire period of recording) is a measure of longer term variation because the beat-to-beat variation is removed by the averaging process.
Chris Crenshaw, the Lincoln Center band's trombonist, was great in "Un Poco Loco," shouting abruptly through his solo as the rhythm went into some variation of a two-beat stomp; Rickey Woodard, Clayton-Hamilton's tenor saxophonist, blazed securely and sumptuously through "Squatty Roo".
The beat-to-beat variation of blood velocity in the descending aorta obtained by the minimally invasive transesophageal echo-doppler method is quite similar to the beat-to-beat variation of the pulse pressure.
