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Table 1 Overview of state variables, variables, parameters and constants used in this paper

From: Diagnostic markers based on a computational model of lipoprotein metabolism

   State Variables - determine the system state
d i, j nm Lipoprotein particle diameter in the i-th step of a lipolysis cascade, in the j-th subclass of the size range covered by that cascade step
Q ss (d i, j ) Particles * dL-1 Steady-state particle pool size in a pool with mean particle diameter d i, j
   Variables - specify processes and output
d i , j r nm the radius of the subclass with average diameter d i, j
J l (d i, j ) Particles *
dL-1 * day-1
Particle flux into the pool with mean particle diameter d i, j due to extrahepatic lipolysis
J l, liver (d i, j ) Particles *
dL-1 * day-1
Particle flux into the pool with mean particle diameter d i, j due to hepatic lipolysis
k l (d) day-1 Particle size dependent extrahepatic lipolysis rate
k a, liver day-1 Particle size dependent liver attachment rate
(attachment is followed by either lipolysis or uptake)
k l, liver (d) day-1 Particle size dependent liver lipolysis rate
k u, liver (d) day-1 Particle size dependent liver uptake rate
n tg (d i, j ) Molecules * particle-1 Number of triglyceride molecules in a lipoprotein particle with diameter d i, j
Q * Particles * dL-1 Steady-state particle pool size in the size range called *
k u , l i v e r * ¯ day-1 Particle size dependent liver uptake rate, averaged per particle over the size range called *
k l ¯ day-1 Particle size dependent extrahepatic lipolysis rate, averaged per particle over all particles in the model
k a , l i v e r ¯ day-1 Particle size dependent liver attachment rate, averaged per particle over all particles in the model
J p,* Particles * dL-1*day-1 Particle production flux into the size range called *
J in, * Particles *
dL-1 * day-1
Particle production influx (production + lipolysis) into the size range called *
Q out ([d a d b ]) Particles * dL-1 Steady state particle pool size in interval from d a todbin the final particle concentration profile.
   Parameters - are optimized using data
k l, max day-1 maximum rate at which extrahepatic lipolysis takes place
k a, apoEmax day-1 maximum rate at which liver binding mediated by ApoE takes place
k a, apoB day-1 rate at which liver binding mediated by ApoB takes place
A nm shape parameter for liver binding mediated by ApoE
B - shape parameter for liver binding mediated by ApoE
σ u, liver nm shape parameter describing fraction of liver attachment which is taken up (instead of lipolyzed) - with changing particle size
   Model constants and derived variables - calibrated in this paper
d a, apoEmin 17 nm minimum particle diameter at which liver binding mediated by ApoE takes place
dhl, peak 31.33 nm Hepatic lipase lipolysis peak size (see Eq. 5)
s u, liver 7.87 Liver uptake shape constant (see Eq. 2)
d l, min 25.13 nm minimum size at which extrahepatic lipolysis occurs (see Eq. 4 in [13])
σ l 77.35 nm shape constant for extrahepatic lipolysis (see Eq. 4 in [13])