A discrete absorbent insert includes a first sheet, a second sheet in facing relation with the first sheet, and an absorbent core positioned between the first sheet and the second sheet. The dielectric membrane can have a thickness substantially smaller than a wavelength of operation of the traveling wave device. for determining a physiological state of a subject, embodied by a method as well as a kit with an immittance measuring circuit and electrodes with contact electrolyte. The method selects glyphs corresponding to intensities of regions in the source image.