Linked Life Data

2262634

Source:http://linkedlifedata.com/resource/pubmed/id/2262634

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1991-2-1
pubmed:abstractText
Amplitude and frequency fluctuations of spontaneous otoacoustic emissions have been studied. Spontaneous otoacoustic emissions were recorded from eight human ears and two frog ears (Rana esculenta). Record length typically was 80 s. For a recorded emission signal, the amplitude signal A(t) (average A0) and time intervals T(ti) between successive positive-going zero crossings (i counts zero crossings) were determined. Emission amplitude and period both showed small fluctuations: delta Arms/A0 ranged from 0.7 X 10(-2) to 6.3 X 10(-2) for human emissions and was 24 X 10(-2) for both frog emissions; delta Trms ranged from 1.4 to 6.9 X 10(-7) s for human emission and was 50.0 and 55.0 X 10(-7) s for the two frog emissions. There was a positive correlation between delta Arms/A0 and delta Trms as determined for different emissions (R = 0.9). Spectra of A(t) and T(ti) revealed that amplitude and period were slowly fluctuating functions: cutoff frequency delta f delta A of the amplitude spectrum ranged from 3 to 18 Hz; delta f delta T ranged from 7 to 32 Hz. Results have been compared to amplitude and frequency fluctuations of a second-order oscillator, that interacts with a noise source. It has been concluded that an oscillator with linear stiffness (for example a Van der Pol oscillator) driven by white Gaussian noise, cannot account for all experimental results. Other possible oscillators (e.g., nonlinear stiffness) and noise sources (e.g., narrow-band noise), that may account for the observed phenomena, are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0001-4966
pubmed:author
pubmed:issnType
Print
pubmed:volume
88
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1779-93
pubmed:dateRevised
2006-12-27
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Amplitude and frequency fluctuations of spontaneous otoacoustic emissions.
pubmed:affiliation
Institute of Audiology, University Hospital, Groningen, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't