According to the PHS, the term "significant financial interest" includes royalty income paid to an investigator except if that income is from the investigator's current employing institution.
Generally, epithelial cells serve the function of protection of the inner layers of the structure they are on. The fact that these columbar epithelium and transitional epithelium cells have smooth walls and are dome shaped allows them to stretch. This stretching helps the bladder retain more urine than it would be able to if the epithelial cells were rigid.
It serves to polarization by transmission through a filter. <span>A Polaroid filter is a device used to polarize light. The device filters out one-half of the vibrations of unpolarized light as the light passes through the filter. Unpolarized light enters the Polaroid filter and the polarized light goes out from the filter. The unpolarized light becomes polarized.</span>