A system and method for dual energy CT spectral imaging that provides for accurate blood vessel stenosis visualization and quantification is disclosed. A backrest is rotatable provided to bearing members at a rear of a base, an operating shaft is laid across a back of the backrest, a lever is provided to a center of the operating shaft. The log data includes a plurality of input values that are input to a specified input field on a specified screen and transmitted to a server in each of the plurality of tests that use the specified screen displayed on a client device. A via hole is formed over and in the substrate and in the metal layers within the spirally patterned conductor layer, the via hole being formed by a through silicon via process. The not-under-printing fingernail is a fingernail not under printing performed by the print head. The device includes a cut surface formed by dicing and constituted by only the substrate and the sealant.