Material that can serve both as a conductor and as an insulator of electricity.

Shimadzu, established in 1875, produced Japan's first x-ray apparatus for medical use in 1909. Today Shimadzu provides a broad range of diagnostic imaging equipment that includes digital x-ray systems, PET systems, CT scanners and diagnostic ultrasound systems.

The range of diagnostics and imaging systems of Siemens Medical Systems covers ultrasound, nuclear medicine, angiography, magnetic resonance, computer tomography and patient monitoring.

(Sv) The sievert is the SI unit of a dose equivalent, which accounts for relative sensitivities of different tissues and organs exposed to radiation. The effective dose, usually measured in millisievert (mSv), attempts to reflect the biological effects of radiation. One sievert equals an ionizing x-ray or gamma radiation energy loss of 1 joule per kilogram of body tissue (1 gray). One sievert is equivalent to 100 rem.
It is named after Rolf Sievert, a Swedish medical physicist.

The signal to noise ratio is a ratio of the signal strength to the noise level (the standard deviation of the signal).