| Autor: |
Abrams, R.M., Gerhardt, K.J. |
| Zdroj: |
Seminars in Perinatology; February 1996, Vol. 20 Issue: 1 p30-37, 8p |
| Abstrakt: |
mechanical vibration of the abdominal wall results in a frequency-related distribution of intra-abdominal sound pressure levels. A greater attenuation of applied signals of equal dynamic force occurs as frequency increases. A broad resonance peak exists between 6 and 18 Hz. Transducers fixed to the fetal head show clear increases in acceleration levels during stimulation of the abdominal surface with the artificial electronic larynx. Sine-wave stimulation results in a frequency-dependent increase in vibration levels of the abdominal wall of 4% to 140% of the input levels. At the fetal head, a broad peak in response was noted between 6 and 12 Hz, but the overall levels never exceeded 4% of the input level. |
| Databáze: |
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| Externí odkaz: |
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