Abstract: An access door for a vehicle including an open bed assembly including a front wall, two side walls and a rear wall. A door portion on one of the side walls of the liftgate opening on a substantially vertical hinged axis for providing side access to the truck bed.

Abstract: The invention provides a method for determining a measure of FRET comprising obtaining sequential fluorescent intensity readings from a specimen, such as a cell using three filter cubes. Simple equations manipulate readings from each of the filter sets or cubes to specify a unitless index of FRET called the FRET ratio (FR). FR bears a linear relation to FRET efficiency E. The method also provides for determining the fraction of acceptor-tagged molecules bound by donor-tagged molecules; the relative affinity of binding; and the strength of FRET interactions when all acceptor-tagged molecules are bound by donor. The latter determination enables estimates of the physical distance and/or orientation between interacting fluorophore molecules. The method can be used to detect analytes or inter- or intramolecular interactions. In a preferred aspect, the method is used in an HTS assay to identify modulators of such interactions.