Causes of T-Wave Abnormality on an EKG. Abnormal T-Waves on an EKG aren't necessarily an indicator of a problem. However, they could cause your doctor to want to do further testing. The heart has its independent electrical systemâ a network of nerves located throughout all its chambers, which mediate electrical impulses that enable chambers to contract in a synchronized rhythm and sequence.
Chronometric definition, a timepiece or timing device with a special mechanism for ensuring and adjusting its accuracy, for use in determining longitude at sea or for any purpose where very exact measurement of time is required. See more.
The term chronometer was coined by Jeremy Thacker of Beverley, England in 1714, referring to his invention of a clock ensconced in a vacuum chamber. The term chronometer is also used to describe a marine chronometer used for celestial navigation and determination of longitude. The marine chronometer was invented by John Harrison in 1730. This was the first of a series of chronometers that enabled accurate marine navigation. From then on, an accurate chronometer was essential to deep sea marine or air navigation out of sight of land.