Table 1.

Description of the different thicknesses (cm) of the regions of interest on the calibration phantom. Four protein concentrations (5%, 10%, 20%, and 30%) were created by placing Delrin on top of some lipid∕water stack. This created 26 regions of interest with unique compositions.

Thicknesses (cm)	4-cm stack				2-cm stack
t_water+t_lipid	4	4	4	4	4	2	2	2
t_water	4	3	2	1	0	2	1	0
t_lipid	0	1	2	3	4	0	1	2
t_protein ∼30%	0.959	0.661	0.486	0.236	0	0.486	0.236	0
t_protein ∼20%	0.661	0.486	0.317	0.159	0	0.317	0.159	0
t_protein ∼10%	0.317	0.236	0.159	0.078	0	0.159	0.078	0
t_protein ∼5%	0.159	0.099	0.078	0.041	0	0.078	0.041	0