Watt within the then-existing system of practical units as "the power conveyed by a current of an Ampère through the difference of potential of a Volt." In October 1908, at the International Conference on Electric Units and Standards in London, so-called "international" definitions were established for practical electrical units. Siemens' definition was adopted as the "international" watt. (Also used: 1 ampere x 1 ohm.) The watt was defined as equal to 10 units of power in the "practical system" of units. The "international units" were dominant from 1909 until 1948. After the 9th General Conference on Weights and Measures in 1948,
Transepithelial potential difference Transepithelial potential difference Transepithelial potential difference (TEPD) is the voltage across an epithelium, and is the sum of the membrane potentials for the outer and inner cell membranes. The diagnosis of Cystic Fibrosis (CF) is usually based on high sweat chloride concentrations, characteristic clinical findings (including sinopulmonary infections), and/or family history. However, a small portion of patients with Cystic Fibrosis especially those with "mild" mutations of the Cystic Fibrosis Transmembrane Regulator ion channel (CFTR), have near-normal sweat tests. In these cases, a useful diagnostic, adjunct involves measuring the nasal transepithelial potential difference (ie, the charge on the respiratory epithelial surface