Inter-beat (RR) Intervals. The time intervals between consecutive heart beats are customarily measured in the electrocardiogram from the beginning of a QRS complex to the beginning of the next QRS complex, so these intervals might be called QQ intervals, but they are conventionally named RR intervals.
Dubuque County, Iowa. Dubuque County is a county located in the U.S. state of Iowa. As of the 2010 census, the population was 93,653. The county seat is Dubuque. The county is named for Julien Dubuque, the first European settler of Iowa. Dubuque County comprises the Dubuque, IA Metropolitan Statistical Area, and is the seventh largest county by population in the state.
Olin, IA. Olin is a city in Jones County, Iowa, United States. The population was 716 at the 2000 census. It is part of the Cedar Rapids Metropolitan Statistical Area. Olin is located at 41Â°59â²51â³N 91Â°8â²24â³W / 41.9975Â°N 91.14Â°W / 41.9975; -91.14 (41.997599, -91.139924). According to the United States Census Bureau, the city has a total area of 1.0 square miles (2.6 kmÂ²), of which, 1.0 square miles (2.6 kmÂ²) of it is land and 1.00% is water.