About: http://webisa.webdatacommons.org/297741250

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	This signal is a marker that is used to subtract the amplified signal from the underlying heart waveform so that the heart waveform can be detected in the presence of the much larger stimulating signal.
http://www.w3.org/ns/prov#wasQuotedFrom	google.co.uk