Fig. 2
From: Model-based estimation of QT intervals of mouse fetal electrocardiogram
A fECG and pulsed Doppler images were obtained from the fetal mouse by using different systems. In order to match Doppler images with fECG records, a signal generator was connected to both systems to input pulsed signals. B The pulse signal that was recorded with fECG is aligned with the same signal that was recorded simultaneously with DUS. Q-Ac intervals were calculated by drawing vertical lines from the Ac timings of DUS to fECG. The red asterisks in fECG indicate the estimated end of T waves. End of T waves were calculated from R(t), Eq. 3. Ac timings were determined by drawing tangent lines where blood flow crosses the base line