The values included by default represents the iodine biokinetic model -see the figure - where compartment 1 is the blood, compartment 2 is the thyroid , compartment 3 is the rest of the body, and "0" mean "out of the system" . The rate transfer values (clearance), in days^-1, taken from ICRP 78 are k10 = 1.9404, k12= 0.8316, k23 = Log[2]/80, k30 = 0.01155 and k31= 0.0462, k30 = 0.01155 and k40 = 12. Them the compartmental matrix is defined:{{1, 2, 0.83}, {1, 4, 1.94}, {2, 3, Log[2]/80}, {3, 0, 0.01155}, {3, 1, 0.0462}, {4, 0, 12}} . Also it assumed the radioactive decay constant of I-131 that is Log[2]/8.02 (days^-1). It assumed a continuouos input "1.2 Exp[-0.2 t]" in compartment 1, then the input is written: {1.2 Exp[-0.2 t], 0, 0, 0}. Also it is supossed as initial contition {1, 0, 0, 0}.

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