euromix.ant

function conc(q,vol)
  piecewise(q/vol, vol > 1e-5, 0)
end

function metab_MM(Vmax, Km, PC, q, vol)
  vol*Vmax*conc(q, vol) / (PC*Km+conc(q, vol))
end

function metab_MA(CLH, PC, q, vol)
  CLH*conc(q, vol)/PC
end

model euromix()

  # Parameters
  
  ## Physiology

  ### Body size
  BM = 70
  BSA = 190
  Height_sc = 0.0001
  Height_vs = 0.0122
  scVFat = 0.209
  scVRich = 0.105
  scVLiver = 0.024
  scVBlood = 0.068

  ### Flow rates
  scFBlood = 4.8
  scFFat = 0.085
  scFPoor = 0.12
  scFLiver = 0.27
  scFSkin = 0.05
  Falv = 2220
  
  ### Tissue density
  rho = 1

  ## Biochemical parameters

  ### Partition coefficients
  PCFat = 2.53
  PCLiver = 0.923
  PCRich = 0.875
  PCPoor = 0.647
  PCSkin_sc = 0.889
  PCSkin = 0.889

  PCAir = 1e+99

  ### Metabolism
  Km = 0
  Michaelis = 0
  Vmax = 0

  ### Others
  fub = 0.51
  fSA_exposed = 0.1
  Kp_sc_vs = 0.01

  ### Excretion
  kGut = 1
  CLH = 132
  Ke = 7.5

  # Assignments
  
  ## Physiology

  ### Body size
  const f_su := Kp_sc_vs * BSA * (1 - fSA_exposed)
  const f_se := Kp_sc_vs * BSA * fSA_exposed
  const VBlood := BM * scVBlood / rho

  ### Flow rates
  const FBlood := scFBlood * BM
  const FFat := FBlood * scFFat
  const FPoor := FBlood * scFPoor
  const FLiver := FBlood * scFLiver
  const FSkin := FBlood * scFSkin
  const FRich := FBlood - FFat - FPoor - FLiver - FSkin
  const FSkin_e := FSkin * fSA_exposed
  const FSkin_u := FSkin - FSkin_e

  # Compartments and Species
  compartment Air
  compartment Urine
  compartment Fat := BM * scVFat / rho
  compartment Rich := BM * scVRich / rho
  compartment Liver := BM * scVLiver / rho
  compartment Art := VBlood / 3.0
  compartment Ven := VBlood - Art
  compartment Skin_e := BSA * Height_vs * fSA_exposed
  compartment Skin_u := BSA * Height_vs * (1 - fSA_exposed)
  compartment Skin_sc_e := BSA * Height_sc * fSA_exposed
  compartment Skin_sc_u := BSA * Height_sc * (1 - fSA_exposed)
  compartment Poor := (BM / rho) - Fat - Rich - Liver - Skin_e - Skin_u - Skin_sc_e - Skin_sc_u - VBlood - 0.1 * (BM / rho)
  compartment Gut

  # Species
  substanceOnly species QFat in Fat
  substanceOnly species QRich in Rich
  substanceOnly species QPoor in Poor
  substanceOnly species QLiver in Liver
  substanceOnly species QMetab in Liver
  substanceOnly species QGut in Gut
  substanceOnly species QSkin_u in Skin_u
  substanceOnly species QSkin_e in Skin_e
  substanceOnly species QSkin_sc_u in Skin_sc_u
  substanceOnly species QSkin_sc_e in Skin_sc_e
  substanceOnly species QArt in Art
  substanceOnly species QVen in Ven
  substanceOnly species QExcret in Urine
  substanceOnly species QAir in Air

  QFat = 0
  QPoor = 0
  QRich = 0
  QGut = 0
  QMetab = 0
  QLiver = 0
  QSkin_u = 0
  QSkin_e = 0
  QSkin_sc_u = 0
  QSkin_sc_e = 0
  QArt = 0
  QVen = 0

  # Model

  ## Absorption
  # Should either be done by events
  # or by adding boundary species

  ## Distribution
  QArt -> QFat; FFat * conc(QArt, Art)
  QFat -> QVen; FFat * conc(QFat, Fat) / PCFat

  QArt -> QRich; FRich * conc(QArt, Art)
  QRich -> QVen; FRich * conc(QRich, Rich) / PCRich

  QArt -> QPoor; FPoor * conc(QArt, Art)
  QPoor -> QVen; FPoor * conc(QPoor, Poor) / PCPoor

  QArt -> QLiver; FLiver * conc(QArt, Art)
  QLiver -> QVen; FLiver * conc(QLiver, Liver) / PCLiver
  QGut -> QLiver; kGut * QGut

  QArt -> QSkin_u; FSkin_u * conc(QArt, Art)
  QSkin_u -> QVen; FSkin_u * conc(QSkin_u, Skin_u) / PCSkin
  QSkin_u -> QSkin_sc_u; f_su * conc(QSkin_u, Skin_u) / PCSkin_sc
  QSkin_sc_u -> QSkin_u; f_su * conc(QSkin_sc_u, Skin_sc_u)

  QArt -> QSkin_e; FSkin_e * conc(QArt, Art)
  QSkin_e -> QVen; FSkin_e * conc(QSkin_e, Skin_e) / PCSkin
  QSkin_e -> QSkin_sc_e; f_se * conc(QSkin_e, Skin_e) / PCSkin_sc
  QSkin_sc_e -> QSkin_e; f_se * conc(QSkin_sc_e, Skin_sc_e)

  QVen -> QArt; FBlood * conc(QVen, Ven)

  ## Metabolism
  QLiver -> QMetab; fub * piecewise(metab_MM(Vmax, Km, PCLiver, QLiver, Liver), Michaelis > 0.5, metab_MA(CLH, PCLiver, QLiver, Liver))

  ## Excretion
  QArt -> QExcret; Ke * fub * conc(QArt, Art)
  
  # Air exchange
  QArt -> QAir; Falv * conc(QArt, Art) / PCAir
  QAir -> QArt; FBlood * conc(QAir, Air)

end