<?xml version='1.0' encoding='UTF-8'?>
<MorpheusModel version="4">
    <Description>
        <Title>Somitogenesis</Title>
        <Details>Full title: A Multi-cell, Multi-scale Model of Vertebrate Segmentation and Somite Formation
Date:	18.08.2023
Authors:	Susann D. Hester, Julio M. Belmonte, J. Scott Gens, Sherry G. Clendenon, James A. Glazier
Curators:	Justin Buerger, Lutz Brusch
Software:	Morpheus (open source). Download from: https://morpheus.gitlab.io
Model ID:	https://identifiers.org/morpheus/M6696
Units:	[time] = 0.015 min
	[space] = 1.43 µm
This model reproduces the model and results obtained with CompuCell3D in the original publication.
Reference:
	Susann D. Hester, Julio M. Belmonte, J. Scott Gens, Sherry G. Clendenon, James A. Glazier: A Multi-cell, Multi-scale Model of Vertebrate Segmentation and Somite Formation. PLoS Comput. Biol. 7(10): e1002155, 2011.
	https://doi.org/10.1371/journal.pcbi.1002155
    </Details>
    </Description>
    <Space>
        <Lattice class="square">
            <Neighborhood>
                <Order>4</Order>
            </Neighborhood>
            <Size symbol="size" value="2*margin + 2*wall + 10*cD, 145*cD, 0.0"/>
            <BoundaryConditions>
                <Condition type="noflux" boundary="x"/>
                <Condition type="noflux" boundary="-x"/>
                <Condition type="noflux" boundary="y"/>
                <Condition type="noflux" boundary="-y"/>
            </BoundaryConditions>
        </Lattice>
        <SpaceSymbol symbol="space"/>
    </Space>
    <Time>
        <StartTime value="0"/>
        <StopTime value="120000"/>
        <TimeSymbol symbol="time"/>
    </Time>
    <Analysis>
        <ModelGraph include-tags="#untagged" format="dot" reduced="false"/>
        <Gnuplotter time-step="200">
            <Terminal name="png" size="1600, 1600, 0"/>
            <Plot title="Cell type">
                <Cells value="cell.type">
                    <ColorMap adaptive-range="false">
                        <Color color="orange" value="0"/>
                        <Color color="gray" value="1"/>
                        <Color color="gray" value="2"/>
                        <Color color="light-salmon" value="3"/>
                        <Color color="light-blue" value="4"/>
                        <Color color="light-green" value="5"/>
                        <Color color="red" value="6"/>
                        <Color color="blue" value="7"/>
                        <Color color="dark-green" value="8"/>
                        <Color color="green" value="9"/>
                        <Color color="white" value="10"/>
                    </ColorMap>
                </Cells>
            </Plot>
            <Plot title="FGF8">
                <Field symbol-ref="FGF" max="45" min="0">
                    <ColorMap adaptive-range="false">
                        <Color color="red" value="45"/>
                        <Color color="yellow" value="33.75"/>
                        <Color color="green" value="22.5"/>
                        <Color color="cyan" value="11.25"/>
                        <Color color="blue" value="0"/>
                    </ColorMap>
                </Field>
            </Plot>
            <Plot title="Lfng">
                <Cells max="2.6" min="0" value="F">
                    <ColorMap adaptive-range="false">
                        <Color color="red" value="2.6"/>
                        <Color color="yellow" value="1.95"/>
                        <Color color="green" value="1.3"/>
                        <Color color="cyan" value="0.65"/>
                        <Color color="blue" value="0"/>
                    </ColorMap>
                </Cells>
            </Plot>
        </Gnuplotter>
    </Analysis>
    <CellTypes>
        <CellType name="Source" class="biological">
            <CellDivision daughterID="daughter" division-plane="oriented" orientation="0.0, -1.0, 0.0">
                <Condition>cell.volume >= 2*tV</Condition>
                <Annotation>Cell Division: as soon as the source cell reaches double its default target volume</Annotation>
                <Triggers>
                    <Rule symbol-ref="targetVolume">
                        <Expression>tV</Expression>
                    </Rule>
                    <Rule symbol-ref="targetSurface">
                        <Expression>tS</Expression>
                    </Rule>
                </Triggers>
            </CellDivision>
            <ChangeCellType time-step="1" newCellType="PSM" name="to PSM">
                <Condition>MediumNeighbor == 0</Condition>
            </ChangeCellType>
            <Property symbol="targetVolume" value="tV"/>
            <Property symbol="targetSurface" value="tS"/>
            <System time-step="1.0" name="Source cell growth" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="targetVolume">
                    <Expression>if((targetVolume &lt; 3*tV), (targetVolume+gR), targetVolume)</Expression>
                </Rule>
                <Rule symbol-ref="targetSurface">
                    <Expression>if((targetVolume &lt; 3*tV), 5*sqrt(targetVolume), targetSurface)</Expression>
                </Rule>
            </System>
            <VolumeConstraint target="targetVolume" strength="LamV"/>
            <SurfaceConstraint target="targetSurface" strength="LamS" mode="surface"/>
            <Property symbol="MediumNeighbor" value="0.0"/>
            <NeighborhoodReporter>
                <Input scaling="cell" value="cell.type == celltype.Medium.id"/>
                <Output symbol-ref="MediumNeighbor" mapping="sum"/>
            </NeighborhoodReporter>
            <Mapper time-step="1.0" name="sense FGF8 at cell center">
                <Input value="if((space.x-1&lt;=cell.center.x &amp;&amp; space.x+1>=cell.center.x &amp;&amp; space.y-1&lt;=cell.center.y &amp;&amp; space.y+1>=cell.center.y),FGF,0)"/>
                <Output symbol-ref="FGF_center" mapping="maximum"/>
            </Mapper>
            <Property symbol="FGF_center" value="45"/>
            <Property symbol="N" name="Notch in the membrane" value="0.1144"/>
            <Property symbol="N_a" name="activated Notch" value="0.7745"/>
            <Property symbol="N_an" name="Activated Notch in the nucleus" value="0.00243"/>
            <Property symbol="N_ap" name="phosphorylated notch" value="0.0013"/>
            <Property symbol="MF" name="lunatic fringe mRNA" value="1.2464"/>
            <Property symbol="F" name="lunatic fringe protein" value="2.3795"/>
            <Property symbol="MDMF" name="delta modification factor mRNA" value="0.0011"/>
            <Property symbol="DMF" name="delta modification factor protein" value="0.2090"/>
            <Property symbol="DL_c" name="delta protein in cytoplasm" value="0.1255"/>
            <Property symbol="DL_m" name="delta protein in the membrane" value="0.0906"/>
            <Property symbol="DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="Sum_DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="PSM_Neighbors" name="Delta outside the cell" value="1"/>
            <NeighborhoodReporter time-step="1.0" name="Delta/Notch from neighboring cells">
                <Input scaling="cell" value="DL_m"/>
                <Output symbol-ref="Sum_DL_mExt" mapping="sum"/>
            </NeighborhoodReporter>
            <NeighborhoodReporter time-step="1.0" name="Neighboring PSM cells">
                <Input scaling="cell" value="(cell.type == celltype.Source.id) + (cell.type == celltype.PSM.id) + (cell.type == celltype.preEphA4.id) + (cell.type == celltype.preCore.id) + (cell.type == celltype.preEphrinB2.id)"/>
                <Output symbol-ref="PSM_Neighbors" mapping="sum"/>
            </NeighborhoodReporter>
            <System time-step="1.0" name="Delta/Notch signaling" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="DL_mExt">
                    <Expression>if(PSM_Neighbors != 0, Sum_DL_mExt/PSM_Neighbors, 0)</Expression>
                </Rule>
            </System>
            <System time-step="1.0" name="Notch loop" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="N">
                    <Expression>eps*(mu_sN-mu_dN*N/(K_dN+N)-(k_c*N*(K_IF^2/(K_IF^2 + F^2))*((DL_mExt/(K_DL +DL_mExt))/(K_aDL + (DL_mExt/(K_DL +DL_mExt))))))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="N_a">
                    <Expression>eps*((k_c*N*(K_IF^2/(K_IF^2 + F^2))*((DL_mExt/(K_DL +DL_mExt))/(K_aDL + (DL_mExt/(K_DL +DL_mExt)))))-mu_dNa*N_a/(K_dNa +N_a)-(k_t1*N_a-k_t2*N_an))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="N_an">
                    <Expression>eps*((k_t1*N_a-k_t2*N_an)-mu_dNan*N_an/(K_dNan + N_an))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MF">
                    <Expression>eps*(mu_sF*(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2/(KA^2 +(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2)-mu_mF*MF/(K_dmF+MF))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="F">
                    <Expression>eps*(k_sF*MF -mu_dF*F/(K_dF+F))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MDMF">
                    <Expression>eps*(mu_s0MDMF*(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2/(K_aNDMF^2+(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2) - mu_dmDMF*MDMF/(K_dmDMF +MDMF))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="DMF">
                    <Expression>eps*(k_sDMF*MDMF - mu_dDMF*DMF/(K_dDMF + DMF))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="DL_c">
                    <Expression>eps*(k_sDL*MDL*(N_an -(mu_Nap*N_an*K/(K_pN+K)))/(K_Nan +(N_an-(mu_Nap*N_an*K/(K_pN+K)))) -k_tDL*DL_c - mu_dDLc*DL_c/(K_dDLc + DL_c))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="DL_m">
                    <Expression>eps*(k_tDL*DL_c - mu_dDLm*DL_m/(K_dDLm + DL_m))</Expression>
                </DiffEqn>
                <Constant symbol="mu_sN" name="maximum rate of notch synthesis" value="0.23*mpm"/>
                <Constant symbol="mu_dN" name="maximum rate of notch degradation" value="2.82*mpm"/>
                <Constant symbol="K_dN" name="michaelis constant for notch degradation" value="1.4"/>
                <Constant symbol="k_c" name="rate for notch cleavage" value="3.45*mpm"/>
                <Constant symbol="mu_dNa" name="maximum rate of cytoplasmic NICD degradation" value="0.01*mpm"/>
                <Constant symbol="K_dNa" name="michaelis constant for cytoplasmic NICD degradation" value="0.001"/>
                <Constant symbol="mu_dNan" name="maximum rate of nuclear NICD degradation" value="0.1*mpm"/>
                <Constant symbol="K_dNan" value="0.001"/>
                <Constant symbol="K_IF" name="threshold constant for inhibition of notch cleavage by Lfng" value="0.45"/>
                <Constant symbol="K_aDL" name="delta signaling threshold constant for notch cleavage" value="0.035"/>
                <Constant symbol="k_t1" name="rate constant for NICD entry into nucleus" value="0.1*mpm"/>
                <Constant symbol="k_t2" value="0.1*mpm"/>
                <Constant symbol="mu_Nap" name="maximum fraction of NICD phosphorylated" value="1.0"/>
                <Constant symbol="K_pN" name="Threshold constant for Gsk3Beta-mediated NICD phosphorylation" value="2.5"/>
                <Constant symbol="mu_sF" name="maximum rate of Lfng transcription" value="3.24*mpm"/>
                <Constant symbol="K_A" name="threshold constant for activation of Lfng gene by NICD" value="0.05"/>
                <Constant symbol="mu_mF" name="maximum rate of Lfng mRNA degradation" value="1.92*mpm"/>
                <Constant symbol="K_dmF" name="michaelis constant for Lfng mRNA degradation" value="0.768"/>
                <Constant symbol="k_sF" name="rate constant for Lfng protein synthesis" value="0.3*mpm"/>
                <Constant symbol="mu_dF" name="maximum rate of Lfng protein degradation" value="0.39*mpm"/>
                <Constant symbol="K_dF" name="michaelis constant for Lfng protein degradation" value="0.37"/>
                <Constant symbol="mu_s0MDMF" name="maximum rate of DMF transcription" value="0.497*mpm"/>
                <Constant symbol="K_aNDMF" name="michaelis constant for notch activation of DMF" value="0.05"/>
                <Constant symbol="mu_dmDMF" name="maximum rate of DMF mRNA degradation" value="0.314*mpm"/>
                <Constant symbol="K_dmDMF" name="michaelis constant for DMD mRNA degradation" value="0.4"/>
                <Constant symbol="k_sDMF" name="rate constant for translation of DMF" value="0.1047*mpm"/>
                <Constant symbol="mu_dDMF" name="maximum rate of DMF protein degradation" value="0.209*mpm"/>
                <Constant symbol="K_dDMF" name="michaelis constant for DMF protein degradation" value="0.5"/>
                <Constant symbol="k_sDL" name="rate constant for delta protein synthesis" value="0.75*mpm"/>
                <Constant symbol="MDL" name="concentration of delta mRNA" value="0.5"/>
                <Constant symbol="K_Nan" name="michaelis constant for NICD stimulation of delta translation" value="0.04"/>
                <Constant symbol="k_tDL" name="rate constant for delta protein transport to membrane" value="0.5*mpm"/>
                <Constant symbol="mu_dDLc" name="maximum rate of delta proteind egradation in cytoplasm" value="0.5*mpm"/>
                <Constant symbol="K_dDLc" name="michaelis constant for delta protein degradation in cytoplasm" value="0.5"/>
                <Constant symbol="mu_dDLm" name="maximum rate of delta protein degradation on membrane" value="0.5*mpm"/>
                <Constant symbol="K_dDLm" name="michaelis constant for delta protein degradation on membrane" value="0.5"/>
                <Constant symbol="K_DL" name="Threshold for delta signaling" value="0.08"/>
                <Constant symbol="eps" name="scaling factor for notch loop" value="0.43"/>
                <Constant symbol="KA" value="0.05"/>
                <Annotation>ODEs for the Notch Loop</Annotation>
            </System>
            <Property symbol="Ras_a" name="Activated Ras protein" value="1.9888"/>
            <Property symbol="ERK_a" name="Activated ERK protein" value="0.01930"/>
            <Property symbol="X_a" name="Activated transcription factor X" value="1.9777"/>
            <Property symbol="MDusp" name="Dusp mRNA" value="2.1651"/>
            <Property symbol="Dusp" name="Dusp protein" value="8.5078"/>
            <Constant symbol="mFgf" name="FGF8 mRNA" value="5"/>
            <System time-step="1.0" name="FGF loop" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="Ras_a">
                    <Expression>eta*(V_MaRas*((FGF_center^2/(K_aFgf^2 + FGF_center^2))*((Ras_t-Ras_a)/(K_aRas + (Ras_t-Ras_a)))-V_MdRas*(Ras_a/(K_dRas+Ras_a))))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="ERK_a">
                    <Expression>eta*(V_MaErk*(Ras_a/Ras_t)*(ERK_t-ERK_a)/(K_aErk + (ERK_t-ERK_a))-K_cDusp*Dusp*ERK_a/(K_dErk+ERK_a))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="X_a">
                    <Expression>eta*(V_MaX*ERK_a/ERK_t*(X_t-X_a)/(K_aX +(X_t-X_a))-V_MdX*X_a/(K_dX + X_a))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MDusp">
                    <Expression>eta*(V_MsMDusp*(X_a^2/(K_aMDusp^2 + X_a^2))*(mu_DuspDMF*K_IMDusp/(K_IMDusp +DMF) +mu_DuspX) - V_MdMDusp*MDusp/(K_dMDusp +MDusp))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="Dusp">
                    <Expression>eta*(K_sDusp*MDusp-V_dDusp*Dusp/(K_dDusp + Dusp))</Expression>
                </DiffEqn>
                <Constant symbol="Ras_t" name="Total concentration of Ras protein" value="2.0"/>
                <Constant symbol="V_MaRas" name="Maximum rate of Ras activation" value="4.968*mpm"/>
                <Constant symbol="K_aFgf" name="FGF8 threshold constant for activation of Ras" value="0.5"/>
                <Constant symbol="K_aRas" name="Inactie Ras threshold constant for activation of Ras" value="0.103"/>
                <Constant symbol="V_MdRas" name="Maximum rate of Ras activation" value="0.41*mpm"/>
                <Constant symbol="K_dRas" name="Michaelis constant of Ras activation" value="0.1"/>
                <Constant symbol="ERK_t" name="Total concentration of ERK protein kinase" value="2.0"/>
                <Constant symbol="V_MaErk" name="Maximum rate of Ras-mediated ERK activation" value="3.3*mpm"/>
                <Constant symbol="K_aErk" name="Inactive ERK threshold constant for ERK activation" value="0.05"/>
                <Constant symbol="K_cDusp" name="Rate constant for inactivation of ERK" value="1.35*mpm"/>
                <Constant symbol="K_dErk" name="Michaelis constant for inactivation of ERK" value="0.05"/>
                <Constant symbol="X_t" name="Total concentration of factor X" value="2.0"/>
                <Constant symbol="V_MaX" name="Maximum rate of ERK-activated X activation" value="1.6*mpm"/>
                <Constant symbol="K_aX" name="Threshold constant for ERK-mediated X activation" value="0.05"/>
                <Constant symbol="V_MdX" name="Maximum rate of X inactivation" value="0.5*mpm"/>
                <Constant symbol="K_dX" name="Michaelis constant for X inactivation" value="0.05"/>
                <Constant symbol="V_MsMDusp" name="maximum rate of Dusp6 transcription" value="0.9*mpm"/>
                <Constant symbol="K_aMDusp" name="Threshold constant for X-activated Dusp6-transcription" value="0.5"/>
                <Constant symbol="V_MdMDusp" name="maximum rate of Dusp6 mRNA degradation" value="0.5*mpm"/>
                <Constant symbol="K_dMDusp" name="Michaelis constant for Dusp6 mRNA degradation" value="0.5"/>
                <Constant symbol="K_sDusp" name="rate constant for Dusp6 translation" value="0.5*mpm"/>
                <Constant symbol="V_dDusp" name="Maximum rate of Dusp6protein degradation" value="2.0*mpm"/>
                <Constant symbol="K_dDusp" name="Michaelis constant for Dusp6 protein degradation" value="0.5"/>
                <Constant symbol="mu_DuspX" name="Fraction of Dusp6 transcription solely regulated by X" value="0.2"/>
                <Constant symbol="mu_DuspDMF" name="Fraction of Dusp6 transcription under regulation by DMF" value="0.8"/>
                <Constant symbol="K_IMDusp" name="Threshold constant for DMF-mediated inhibition of Dusp6" value="0.3"/>
                <Constant symbol="eta" name="Scaling factor for FGF8 loop" value="0.328"/>
                <Annotation>ODEs for the FGF Loop</Annotation>
            </System>
            <Property symbol="K" name="Free Gsk3 protein" value="1.4428"/>
            <Property symbol="B" name="Beta-Katenin" value="0.4705"/>
            <Property symbol="B_p" name="Phosphorylated beta catenin" value="0.0090"/>
            <Property symbol="B_n" value="0.2146"/>
            <Property symbol="MAx" name="Axin2 mRNA" value="0.1523"/>
            <Property symbol="A" name="Axin2 protein" value="0.0461"/>
            <System time-step="1.0" name="Wnt loop" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="K">
                    <Expression>teta*(d_1*(K_t-K)-a_1*A*K)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="B">
                    <Expression>teta*(mu_sB-(V_MK*K_ID/(K_ID+Wnt)*B/(K_1+B))*(K_t-K)/K_t+(V_MP*B_p/(K_2+B_p))+(k_t4*B_n-k_t3*B)-k_d1*B)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="B_p">
                    <Expression>teta*((V_MK*K_ID/(K_ID+Wnt)*B/(K_1+B))*(K_t-K)/K_t-(V_MP*B_p/(K_2+B_p))-k_d2*B_p)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="B_n">
                    <Expression>-teta*(k_t4*B_n-k_t3*B)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MAx">
                    <Expression>teta*(mu_0+mu_MB*B_n^2/(K_aB^2+B_n^2)+mu_MXa*X_a^2/(K_aXa^2+X_a^2)-mu_md*MAx/(K_md+MAx))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="A">
                    <Expression>teta*(k_sAx*MAx-mu_dAx*A/(K_dAx+A)+(d_1*(K_t-K)-a_1*A*K))</Expression>
                </DiffEqn>
                <Constant symbol="a_1" name="Rate constant for Gsk3-Axin-Binding" value="1.8*mpm"/>
                <Constant symbol="d_1" name="Rate constant for Gsk3-Axin dissociation" value="0.1*mpm"/>
                <Constant symbol="mu_sB" name="Maximum rate of beta-catenin synthesis" value="0.087*mpm"/>
                <Constant symbol="k_t3" name="Rate constant for beta-catenin entry into nucleus" value="0.7*mpm"/>
                <Constant symbol="k_t4" name="Rate constant for beta-catenin exit from nucleus" value="1.5*mpm"/>
                <Constant symbol="V_MK" name="Maximum rate of Gsk3Beta-medaited beta-catein phosphorylation" value="4.5*mpm"/>
                <Constant symbol="K_t" name="Total Gsk3Beta concentration" value="3.0"/>
                <Constant symbol="K_ID" name="Threshold constant for Dsh inhibition of beta-catenin phosphorylation" value="0.5"/>
                <Constant symbol="K_1" name="Michaelis constant for beta-catenin phosphorylation" value="0.28"/>
                <Constant symbol="V_MP" name="Maximum rate of beta-catenin dephosphorylation" value="1.0*mpm"/>
                <Constant symbol="K_2" name="Michaelis constant for b-catenin dephosphorylation" value="0.03 "/>
                <Constant symbol="k_d1" name="Rate constant for unphosphorylated b-catenin degradation" value="0.0*mpm"/>
                <Constant symbol="k_d2" name="rate constant for phosphorylated beta-catenin degradation" value="7.062*mpm"/>
                <Constant symbol="mu_0" name="Basal rate of Axin2 transcription" value="0.06*mpm"/>
                <Constant symbol="mu_MB" name="Maximum rate of beta-catenin activated Axin2 transcription" value="1.64*mpm"/>
                <Constant symbol="K_aB" name="Threshold constant for beta-catenon activation of Axin2" value="0.7"/>
                <Constant symbol="mu_md" name="Maximum rate of Axin2 mRNA degradation" value="0.8*mpm"/>
                <Constant symbol="K_md" name="Michaelis constant for Axin2 mRNA degradation" value="0.48"/>
                <Constant symbol="mu_MXa" name="Maximum rate of Xa activated Axin2 transcription" value="0.5*mpm"/>
                <Constant symbol="K_aXa" name="Threshold constant for Xa activation of Axin2" value="0.05"/>
                <Constant symbol="k_sAx" name="rate constant for axin2 translation" value="0.02*mpm"/>
                <Constant symbol="mu_dAx" name="Maximum rate of Axin2 protein degradation" value="0.6*mpm"/>
                <Constant symbol="K_dAx" name="Michaelis constant for Axin2 protein degradation" value="0.63"/>
                <Constant symbol="teta" name="scaling factor for the Wnt loop" value="1.12"/>
                <Annotation>ODEs for the Wnt Loop</Annotation>
            </System>
            <Constant symbol="Wnt" value="C_12w*mFgf"/>
            <Constant symbol="C_12w" name="Factor relating Wnt concentration and fgf mRNA concentration" value="0.32"/>
            <CellDeath name="Leave the lattice at posterior boundary">
                <Condition>cell.center.y &lt; cD</Condition>
            </CellDeath>
        </CellType>
        <CellType name="Wall" class="biological">
            <FreezeMotion>
                <Condition>1</Condition>
            </FreezeMotion>
            <ChangeCellType newCellType="Wall_Off" name="to Wall_Off">
                <Condition>(cell.center.y >= wallDeath +5) + (cell.center.y &lt; cD)*(wallDeath &lt; 1.5*cD)</Condition>
            </ChangeCellType>
            <Constant symbol="mFgf" value="0"/>
            <Constant symbol="F" name="lunatic fringe protein" value="0"/>
        </CellType>
        <CellType name="Wall_Off" class="biological">
            <FreezeMotion>
                <Condition>1</Condition>
            </FreezeMotion>
            <Property symbol="ticker" value="1"/>
            <System time-step="1.0" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="ticker">
                    <Expression>ticker-1</Expression>
                </Rule>
            </System>
            <CellDeath>
                <Condition>ticker &lt;= 0 </Condition>
            </CellDeath>
            <Constant symbol="mFgf" value="0"/>
            <Constant symbol="F" name="lunatic fringe protein" value="0"/>
        </CellType>
        <CellType name="preEphA4" class="biological">
            <VolumeConstraint target="tV" strength="LamV"/>
            <SurfaceConstraint target="tS" strength="LamS" mode="surface"/>
            <Mapper time-step="1.0" name="sense FGF8 at cell center">
                <Input value="if((space.x-1&lt;=cell.center.x &amp;&amp; space.x+1>=cell.center.x &amp;&amp; space.y-1&lt;=cell.center.y &amp;&amp; space.y+1>=cell.center.y),FGF,0)"/>
                <Output symbol-ref="FGF_center" mapping="maximum"/>
            </Mapper>
            <Property symbol="FGF_center" value="45"/>
            <Property symbol="DL_m" name="delta protein in the membrane" value="0.0906"/>
            <Property symbol="DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="F" name="lunatic fringe protein" value="0.0006"/>
            <NeighborhoodReporter time-step="1.0" name="Delta/Notch from Neighboring cells">
                <Input scaling="cell" value="DL_m"/>
                <Output symbol-ref="DL_mExt" mapping="average"/>
            </NeighborhoodReporter>
            <Property symbol="mFgf" name="FGF8 mRNA" value="5"/>
            <System time-step="1.0" name="FGF8" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="mFgf" name="Decay, only for PSM cells">
                    <Expression>-k_fgf_cell*mFgf</Expression>
                </DiffEqn>
            </System>
            <Property symbol="Wnt" value="C_12w*mFgf"/>
            <Constant symbol="C_12w" name="Factor relating Wnt concentration and fgf mRNA concentration" value="0.32"/>
            <System time-step="1.0" name="Wnt" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="Wnt" name="Wnt decay">
                    <Expression>C_12w*mFgf</Expression>
                </Rule>
            </System>
            <ChangeCellType newCellType="EphA4" name="to EphA4">
                <Condition>ticker &lt; 1</Condition>
                <Triggers name="set_wall_death">
                    <Rule symbol-ref="wallDeath">
                        <Expression>cell.center.y</Expression>
                    </Rule>
                </Triggers>
            </ChangeCellType>
            <Property symbol="ticker" name="determiantion ticker" value="24000"/>
            <System time-step="1.0" name="determination ticker" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="ticker">
                    <Expression>ticker-1</Expression>
                </Rule>
            </System>
        </CellType>
        <CellType name="preEphrinB2" class="biological">
            <VolumeConstraint target="tV" strength="LamV"/>
            <SurfaceConstraint target="tS" strength="LamS" mode="surface"/>
            <Mapper time-step="1.0" name="sense FGF8 at cell center">
                <Input value="if((space.x-1&lt;=cell.center.x &amp;&amp; space.x+1>=cell.center.x &amp;&amp; space.y-1&lt;=cell.center.y &amp;&amp; space.y+1>=cell.center.y),FGF,0)"/>
                <Output symbol-ref="FGF_center" mapping="maximum"/>
            </Mapper>
            <Property symbol="FGF_center" value="45"/>
            <Property symbol="DL_m" name="delta protein in the membrane" value="0.0906"/>
            <Property symbol="DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="F" name="lunatic fringe protein" value="0.0006"/>
            <Property symbol="Sum_DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="PSM_Neighbors" name="Delta outside the cell" value="1"/>
            <NeighborhoodReporter time-step="1.0" name="Delta/Notch from Neighboring cells">
                <Input scaling="cell" value="DL_m"/>
                <Output symbol-ref="Sum_DL_mExt" mapping="sum"/>
            </NeighborhoodReporter>
            <NeighborhoodReporter time-step="1.0" name="Neighboring PSM cells">
                <Input scaling="cell" value="(cell.type == celltype.Source.id) + (cell.type == celltype.PSM.id) + (cell.type == celltype.preEphA4.id) + (cell.type == celltype.preCore.id) + (cell.type == celltype.preEphrinB2.id)"/>
                <Output symbol-ref="PSM_Neighbors" mapping="sum"/>
            </NeighborhoodReporter>
            <System time-step="1.0" name="Delta/Notch signaling" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="DL_mExt">
                    <Expression>if(PSM_Neighbors != 0, Sum_DL_mExt/PSM_Neighbors, 0)</Expression>
                </Rule>
            </System>
            <Property symbol="mFgf" name="FGF8 mRNA" value="5"/>
            <System time-step="1.0" name="FGF8" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="mFgf" name="Decay, only for PSM cells">
                    <Expression>-k_fgf_cell*mFgf</Expression>
                </DiffEqn>
            </System>
            <Property symbol="Wnt" value="C_12w*mFgf"/>
            <Constant symbol="C_12w" name="Factor relating Wnt concentration and fgf mRNA concentration" value="0.32"/>
            <System time-step="1.0" name="Wnt" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="Wnt">
                    <Expression>C_12w*mFgf</Expression>
                </Rule>
            </System>
            <ChangeCellType newCellType="EphrinB2" name="to EphrinB2">
                <Condition>ticker &lt; 1</Condition>
                <Triggers name="set_wall_death">
                    <Rule symbol-ref="wallDeath">
                        <Expression>cell.center.y</Expression>
                    </Rule>
                </Triggers>
            </ChangeCellType>
            <Property symbol="ticker" name="determiantion ticker" value="24000"/>
            <System time-step="1.0" name="determination ticker" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="ticker">
                    <Expression>ticker-1</Expression>
                </Rule>
            </System>
        </CellType>
        <CellType name="preCore" class="biological">
            <VolumeConstraint target="tV" strength="LamV"/>
            <SurfaceConstraint target="tS" strength="LamS" mode="surface"/>
            <Mapper time-step="1.0" name="sense FGF8 at cell center">
                <Input value="if((space.x-1&lt;=cell.center.x &amp;&amp; space.x+1>=cell.center.x &amp;&amp; space.y-1&lt;=cell.center.y &amp;&amp; space.y+1>=cell.center.y),FGF,0)"/>
                <Output symbol-ref="FGF_center" mapping="maximum"/>
            </Mapper>
            <Property symbol="FGF_center" value="45"/>
            <Property symbol="DL_m" name="delta protein in the membrane" value="0.0906"/>
            <Property symbol="DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="F" name="lunatic fringe protein" value="0.0006"/>
            <Property symbol="Sum_DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="PSM_Neighbors" name="Delta outside the cell" value="1"/>
            <NeighborhoodReporter time-step="1.0" name="Delta/Notch from Neighboring cells">
                <Input scaling="cell" value="DL_m"/>
                <Output symbol-ref="Sum_DL_mExt" mapping="sum"/>
            </NeighborhoodReporter>
            <NeighborhoodReporter time-step="1.0" name="Neighboring PSM cells">
                <Input scaling="cell" value="(cell.type == celltype.Source.id) + (cell.type == celltype.PSM.id) + (cell.type == celltype.preEphA4.id) + (cell.type == celltype.preCore.id) + (cell.type == celltype.preEphrinB2.id)"/>
                <Output symbol-ref="PSM_Neighbors" mapping="sum"/>
            </NeighborhoodReporter>
            <System time-step="1.0" name="Delta/Notch signaling" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="DL_mExt">
                    <Expression>if(PSM_Neighbors != 0, Sum_DL_mExt/PSM_Neighbors, 0)</Expression>
                </Rule>
            </System>
            <Property symbol="mFgf" name="FGF8 mRNA" value="5"/>
            <System time-step="1.0" name="FGF8" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="mFgf" name="Decay, only for PSM cells">
                    <Expression>-k_fgf_cell*mFgf</Expression>
                </DiffEqn>
            </System>
            <Property symbol="Wnt" value="C_12w*mFgf"/>
            <Constant symbol="C_12w" name="Factor relating Wnt concentration and fgf mRNA concentration" value="0.32"/>
            <System time-step="1.0" name="Wnt" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="Wnt" name="Wnt decay">
                    <Expression>C_12w*mFgf</Expression>
                </Rule>
            </System>
            <ChangeCellType newCellType="Core" name="to Core">
                <Condition>ticker &lt; 1</Condition>
                <Triggers name="set_wall_death">
                    <Rule symbol-ref="wallDeath">
                        <Expression>cell.center.y</Expression>
                    </Rule>
                </Triggers>
            </ChangeCellType>
            <Property symbol="ticker" name="determiantion ticker" value="24000"/>
            <System time-step="1.0" name="determination ticker" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="ticker">
                    <Expression>ticker-1</Expression>
                </Rule>
            </System>
        </CellType>
        <CellType name="EphA4" class="biological">
            <VolumeConstraint target="tV" strength="LamV"/>
            <SurfaceConstraint target="tS" strength="LamS" mode="surface"/>
            <Constant symbol="mFgf" value="0.0"/>
            <Property symbol="F" name="lunatic fringe protein" value="0.0006"/>
        </CellType>
        <CellType name="EphrinB2" class="biological">
            <VolumeConstraint target="tV" strength="LamV"/>
            <SurfaceConstraint target="tS" strength="LamS" mode="surface"/>
            <Constant symbol="mFgf" value="0.0"/>
            <Property symbol="F" name="lunatic fringe protein" value="0.0006"/>
        </CellType>
        <CellType name="Core" class="biological">
            <VolumeConstraint target="tV" strength="LamV"/>
            <SurfaceConstraint target="tS" strength="LamS" mode="surface"/>
            <Constant symbol="mFgf" value="0.0"/>
            <Property symbol="F" name="lunatic fringe protein" value="0.0006"/>
        </CellType>
        <CellType name="PSM" class="biological">
            <VolumeConstraint target="tV" strength="LamV"/>
            <SurfaceConstraint target="tS" strength="LamS" mode="surface"/>
            <Property symbol="FGF_center" value="45"/>
            <Property symbol="N" name="Notch in the membrane" value="0.1144"/>
            <Property symbol="N_a" name="activated Notch" value="0.7745"/>
            <Property symbol="N_an" name="Activated Notch in the nucleus" value="0.00243"/>
            <Property symbol="N_ap" name="phosphorylated notch" value="0.0013"/>
            <Property symbol="MF" name="lunatic fringe mRNA" value="1.2464"/>
            <Property symbol="F" name="lunatic fringe protein" value="2.3795"/>
            <Property symbol="MDMF" name="delta modification factor mRNA" value="0.0011"/>
            <Property symbol="DMF" name="delta modification factor protein" value="0.2090"/>
            <Property symbol="DL_c" name="delta protein in cytoplasm" value="0.1255"/>
            <Property symbol="DL_m" name="delta protein in the membrane" value="0.0906"/>
            <Property symbol="DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="Sum_DL_mExt" name="Delta outside the cell" value="DL_m"/>
            <Property symbol="PSM_Neighbors" name="Delta outside the cell" value="1"/>
            <NeighborhoodReporter time-step="1.0" name="Delta/Notch from Neighboring cells">
                <Input scaling="cell" value="DL_m"/>
                <Output symbol-ref="Sum_DL_mExt" mapping="sum"/>
            </NeighborhoodReporter>
            <NeighborhoodReporter time-step="1.0" name="Neighboring PSM cells">
                <Input scaling="cell" value="(cell.type == celltype.Source.id) + (cell.type == celltype.PSM.id) + (cell.type == celltype.preEphA4.id) + (cell.type == celltype.preCore.id) + (cell.type == celltype.preEphrinB2.id)"/>
                <Output symbol-ref="PSM_Neighbors" mapping="sum"/>
            </NeighborhoodReporter>
            <System time-step="1.0" name="Delta/Notch signaling" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="DL_mExt">
                    <Expression>if(PSM_Neighbors != 0, Sum_DL_mExt/PSM_Neighbors, 0)</Expression>
                </Rule>
            </System>
            <System time-step="1.0" name="Notch loop" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="N">
                    <Expression>eps*(mu_sN-mu_dN*N/(K_dN+N)-(k_c*N*(K_IF^2/(K_IF^2 + F^2))*((DL_mExt/(K_DL +DL_mExt))/(K_aDL + (DL_mExt/(K_DL +DL_mExt))))))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="N_a">
                    <Expression>eps*((k_c*N*(K_IF^2/(K_IF^2 + F^2))*((DL_mExt/(K_DL +DL_mExt))/(K_aDL + (DL_mExt/(K_DL +DL_mExt)))))-mu_dNa*N_a/(K_dNa +N_a)-(k_t1*N_a-k_t2*N_an))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="N_an">
                    <Expression>eps*((k_t1*N_a-k_t2*N_an)-mu_dNan*N_an/(K_dNan + N_an))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MF">
                    <Expression>eps*(mu_sF*(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2/(KA^2 +(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2)-mu_mF*MF/(K_dmF+MF))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="F">
                    <Expression>eps*(k_sF*MF -mu_dF*F/(K_dF+F))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MDMF">
                    <Expression>eps*(mu_s0MDMF*(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2/(K_aNDMF^2+(N_an-(mu_Nap*N_an*K/(K_pN+K)))^2) - mu_dmDMF*MDMF/(K_dmDMF +MDMF))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="DMF">
                    <Expression>eps*(k_sDMF*MDMF - mu_dDMF*DMF/(K_dDMF + DMF))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="DL_c">
                    <Expression>eps*(k_sDL*MDL*(N_an -(mu_Nap*N_an*K/(K_pN+K)))/(K_Nan +(N_an-(mu_Nap*N_an*K/(K_pN+K)))) -k_tDL*DL_c - mu_dDLc*DL_c/(K_dDLc + DL_c))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="DL_m">
                    <Expression>eps*(k_tDL*DL_c - mu_dDLm*DL_m/(K_dDLm + DL_m))</Expression>
                </DiffEqn>
                <Constant symbol="mu_sN" name="maximum rate of notch synthesis" value="0.23*mpm"/>
                <Constant symbol="mu_dN" name="maximum rate of notch degradation" value="2.82*mpm"/>
                <Constant symbol="K_dN" name="michaelis constant for notch degradation" value="1.4"/>
                <Constant symbol="k_c" name="rate for notch cleavage" value="3.45*mpm"/>
                <Constant symbol="mu_dNa" name="maximum rate of cytoplasmic NICD degradation" value="0.01*mpm"/>
                <Constant symbol="K_dNa" name="michaelis constant for cytoplasmic NICD degradation" value="0.001"/>
                <Constant symbol="mu_dNan" name="maximum rate of nuclear NICD degradation" value="0.1*mpm"/>
                <Constant symbol="K_dNan" value="0.001"/>
                <Constant symbol="K_IF" name="threshold constant for inhibition of notch cleavage by Lfng" value="0.45"/>
                <Constant symbol="K_aDL" name="delta signaling threshold constant for notch cleavage" value="0.035"/>
                <Constant symbol="k_t1" name="rate constant for NICD entry into nucleus" value="0.1*mpm"/>
                <Constant symbol="k_t2" value="0.1*mpm"/>
                <Constant symbol="mu_Nap" name="maximum fraction of NICD phosphorylated" value="1.0"/>
                <Constant symbol="K_pN" name="Threshold constant for Gsk3Beta-mediated NICD phosphorylation" value="2.5"/>
                <Constant symbol="mu_sF" name="maximum rate of Lfng transcription" value="3.24*mpm"/>
                <Constant symbol="K_A" name="threshold constant for activation of Lfng gene by NICD" value="0.05"/>
                <Constant symbol="mu_mF" name="maximum rate of Lfng mRNA degradation" value="1.92*mpm"/>
                <Constant symbol="K_dmF" name="michaelis constant for Lfng mRNA degradation" value="0.768"/>
                <Constant symbol="k_sF" name="rate constant for Lfng protein synthesis" value="0.3*mpm"/>
                <Constant symbol="mu_dF" name="maximum rate of Lfng protein degradation" value="0.39*mpm"/>
                <Constant symbol="K_dF" name="michaelis constant for Lfng protein degradation" value="0.37"/>
                <Constant symbol="mu_s0MDMF" name="maximum rate of DMF transcription" value="0.497*mpm"/>
                <Constant symbol="K_aNDMF" name="michaelis constant for notch activation of DMF" value="0.05"/>
                <Constant symbol="mu_dmDMF" name="maximum rate of DMF mRNA degradation" value="0.314*mpm"/>
                <Constant symbol="K_dmDMF" name="michaelis constant for DMD mRNA degradation" value="0.4"/>
                <Constant symbol="k_sDMF" name="rate constant for translation of DMF" value="0.1047*mpm"/>
                <Constant symbol="mu_dDMF" name="maximum rate of DMF protein degradation" value="0.209*mpm"/>
                <Constant symbol="K_dDMF" name="michaelis constant for DMF protein degradation" value="0.5"/>
                <Constant symbol="k_sDL" name="rate constant for delta protein synthesis" value="0.75*mpm"/>
                <Constant symbol="MDL" name="concentration of delta mRNA" value="0.5"/>
                <Constant symbol="K_Nan" name="michaelis constant for NICD stimulation of delta translation" value="0.04"/>
                <Constant symbol="k_tDL" name="rate constant for delta protein transport to membrane" value="0.5*mpm"/>
                <Constant symbol="mu_dDLc" name="maximum rate of delta proteind egradation in cytoplasm" value="0.5*mpm"/>
                <Constant symbol="K_dDLc" name="michaelis constant for delta protein degradation in cytoplasm" value="0.5"/>
                <Constant symbol="mu_dDLm" name="maximum rate of delta protein degradation on membrane" value="0.5*mpm"/>
                <Constant symbol="K_dDLm" name="michaelis constant for delta protein degradation on membrane" value="0.5"/>
                <Constant symbol="K_DL" name="Threshold for delta signaling" value="0.08"/>
                <Constant symbol="eps" name="scaling factor for notch loop" value="0.43"/>
                <Constant symbol="KA" value="0.05"/>
                <Annotation>ODEs for the Notch Loop</Annotation>
            </System>
            <Property symbol="Ras_a" name="Activated Ras protein" value="1.9888"/>
            <Property symbol="ERK_a" name="Activated ERK protein" value="0.01930"/>
            <Property symbol="X_a" name="Activated transcription factor X" value="1.9777"/>
            <Property symbol="MDusp" name="Dusp mRNA" value="2.1651"/>
            <Property symbol="Dusp" name="Dusp protein" value="8.5078"/>
            <Property symbol="mFgf" name="FGF8 mRNA" value="if((size.y-4*cD-cell.center.y>0)*(size.y-4*cD-cell.center.y&lt;=cD), 4.4, if((size.y-4*cD-cell.center.y>cD)*(size.y-4*cD-cell.center.y&lt;=(cD)*2), 4.6, if((size.y-4*cD-cell.center.y>(cD)*2), 4.8, 4.8)))"/>
            <System time-step="1.0" name="FGF loop" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="Ras_a">
                    <Expression>eta*(V_MaRas*((FGF_center^2/(K_aFgf^2 + FGF_center^2))*((Ras_t-Ras_a)/(K_aRas + (Ras_t-Ras_a)))-V_MdRas*(Ras_a/(K_dRas+Ras_a))))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="ERK_a">
                    <Expression>eta*(V_MaErk*(Ras_a/Ras_t)*(ERK_t-ERK_a)/(K_aErk + (ERK_t-ERK_a))-K_cDusp*Dusp*ERK_a/(K_dErk+ERK_a))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="X_a">
                    <Expression>eta*(V_MaX*ERK_a/ERK_t*(X_t-X_a)/(K_aX +(X_t-X_a))-V_MdX*X_a/(K_dX + X_a))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MDusp">
                    <Expression>eta*(V_MsMDusp*(X_a^2/(K_aMDusp^2 + X_a^2))*(mu_DuspDMF*K_IMDusp/(K_IMDusp +DMF) +mu_DuspX) - V_MdMDusp*MDusp/(K_dMDusp +MDusp))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="Dusp">
                    <Expression>eta*(K_sDusp*MDusp-V_dDusp*Dusp/(K_dDusp + Dusp))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="mFgf" name="Decay, only for PSM cells">
                    <Expression>-k_fgf_cell*mFgf</Expression>
                </DiffEqn>
                <Constant symbol="Ras_t" name="Total concentration of Ras protein" value="2.0"/>
                <Constant symbol="V_MaRas" name="Maximum rate of Ras activation" value="4.968*mpm"/>
                <Constant symbol="K_aFgf" name="FGF8 threshold constant for activation of Ras" value="0.5"/>
                <Constant symbol="K_aRas" name="Inactie Ras threshold constant for activation of Ras" value="0.103"/>
                <Constant symbol="V_MdRas" name="Maximum rate of Ras activation" value="0.41*mpm"/>
                <Constant symbol="K_dRas" name="Michaelis constant of Ras activation" value="0.1"/>
                <Constant symbol="ERK_t" name="Total concentration of ERK protein kinase" value="2.0"/>
                <Constant symbol="V_MaErk" name="Maximum rate of Ras-mediated ERK activation" value="3.3*mpm"/>
                <Constant symbol="K_aErk" name="Inactive ERK threshold constant for ERK activation" value="0.05"/>
                <Constant symbol="K_cDusp" name="Rate constant for inactivation of ERK" value="1.35*mpm"/>
                <Constant symbol="K_dErk" name="Michaelis constant for inactivation of ERK" value="0.05"/>
                <Constant symbol="X_t" name="Total concentration of factor X" value="2.0"/>
                <Constant symbol="V_MaX" name="Maximum rate of ERK-activated X activation" value="1.6*mpm"/>
                <Constant symbol="K_aX" name="Threshold constant for ERK-mediated X activation" value="0.05"/>
                <Constant symbol="V_MdX" name="Maximum rate of X inactivation" value="0.5*mpm"/>
                <Constant symbol="K_dX" name="Michaelis constant for X inactivation" value="0.05"/>
                <Constant symbol="V_MsMDusp" name="maximum rate of Dusp6 transcription" value="0.9*mpm"/>
                <Constant symbol="K_aMDusp" name="Threshold constant for X-activated Dusp6-transcription" value="0.5"/>
                <Constant symbol="V_MdMDusp" name="maximum rate of Dusp6 mRNA degradation" value="0.5*mpm"/>
                <Constant symbol="K_dMDusp" name="Michaelis constant for Dusp6 mRNA degradation" value="0.5"/>
                <Constant symbol="K_sDusp" name="rate constant for Dusp6 translation" value="0.5*mpm"/>
                <Constant symbol="V_dDusp" name="Maximum rate of Dusp6protein degradation" value="2.0*mpm"/>
                <Constant symbol="K_dDusp" name="Michaelis constant for Dusp6 protein degradation" value="0.5"/>
                <Constant symbol="mu_DuspX" name="Fraction of Dusp6 transcription solely regulated by X" value="0.2"/>
                <Constant symbol="mu_DuspDMF" name="Fraction of Dusp6 transcription under regulation by DMF" value="0.8"/>
                <Constant symbol="K_IMDusp" name="Threshold constant for DMF-mediated inhibition of Dusp6" value="0.3"/>
                <Constant symbol="eta" name="Scaling factor for FGF8 loop" value="0.328"/>
                <Annotation>ODEs for the FGF Loop</Annotation>
            </System>
            <Property symbol="K" name="Free Gsk3 protein" value="1.4428"/>
            <Property symbol="B" name="Beta-Katenin" value="0.4705"/>
            <Property symbol="B_p" name="Phosphorylated beta catenin" value="0.0090"/>
            <Property symbol="B_n" value="0.2146"/>
            <Property symbol="MAx" name="Axin2 mRNA" value="0.1523"/>
            <Property symbol="A" name="Axin2 protein" value="0.0461"/>
            <System time-step="1.0" name="Wnt loop" solver="Runge-Kutta [fixed, O(4)]">
                <DiffEqn symbol-ref="K">
                    <Expression>teta*(d_1*(K_t-K)-a_1*A*K)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="B">
                    <Expression>teta*(mu_sB-(V_MK*K_ID/(K_ID+Wnt)*B/(K_1+B))*(K_t-K)/K_t+(V_MP*B_p/(K_2+B_p))+(k_t4*B_n-k_t3*B)-k_d1*B)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="B_p">
                    <Expression>teta*((V_MK*K_ID/(K_ID+Wnt)*B/(K_1+B))*(K_t-K)/K_t-(V_MP*B_p/(K_2+B_p))-k_d2*B_p)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="B_n">
                    <Expression>-teta*(k_t4*B_n-k_t3*B)</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="MAx">
                    <Expression>teta*(mu_0+mu_MB*B_n^2/(K_aB^2+B_n^2)+mu_MXa*X_a^2/(K_aXa^2+X_a^2)-mu_md*MAx/(K_md+MAx))</Expression>
                </DiffEqn>
                <DiffEqn symbol-ref="A">
                    <Expression>teta*(k_sAx*MAx-mu_dAx*A/(K_dAx+A)+(d_1*(K_t-K)-a_1*A*K))</Expression>
                </DiffEqn>
                <Constant symbol="a_1" name="Rate constant for Gsk3-Axin-Binding" value="1.8*mpm"/>
                <Constant symbol="d_1" name="Rate constant for Gsk3-Axin dissociation" value="0.1*mpm"/>
                <Constant symbol="mu_sB" name="Maximum rate of beta-catenin synthesis" value="0.087*mpm"/>
                <Constant symbol="k_t3" name="Rate constant for beta-catenin entry into nucleus" value="0.7*mpm"/>
                <Constant symbol="k_t4" name="Rate constant for beta-catenin exit from nucleus" value="1.5*mpm"/>
                <Constant symbol="V_MK" name="Maximum rate of Gsk3Beta-medaited beta-catein phosphorylation" value="4.5*mpm"/>
                <Constant symbol="K_t" name="Total Gsk3Beta concentration" value="3.0"/>
                <Constant symbol="K_ID" name="Threshold constant for Dsh inhibition of beta-catenin phosphorylation" value="0.5"/>
                <Constant symbol="K_1" name="Michaelis constant for beta-catenin phosphorylation" value="0.28"/>
                <Constant symbol="V_MP" name="Maximum rate of beta-catenin dephosphorylation" value="1.0*mpm"/>
                <Constant symbol="K_2" name="Michaelis constant for b-catenin dephosphorylation" value="0.03 "/>
                <Constant symbol="k_d1" name="Rate constant for unphosphorylated b-catenin degradation" value="0.0*mpm"/>
                <Constant symbol="k_d2" name="rate constant for phosphorylated beta-catenin degradation" value="7.062*mpm"/>
                <Constant symbol="mu_0" name="Basal rate of Axin2 transcription" value="0.06*mpm"/>
                <Constant symbol="mu_MB" name="Maximum rate of beta-catenin activated Axin2 transcription" value="1.64*mpm"/>
                <Constant symbol="K_aB" name="Threshold constant for beta-catenon activation of Axin2" value="0.7"/>
                <Constant symbol="mu_md" name="Maximum rate of Axin2 mRNA degradation" value="0.8*mpm"/>
                <Constant symbol="K_md" name="Michaelis constant for Axin2 mRNA degradation" value="0.48"/>
                <Constant symbol="mu_MXa" name="Maximum rate of Xa activated Axin2 transcription" value="0.5*mpm"/>
                <Constant symbol="K_aXa" name="Threshold constant for Xa activation of Axin2" value="0.05"/>
                <Constant symbol="k_sAx" name="rate constant for axin2 translation" value="0.02*mpm"/>
                <Constant symbol="mu_dAx" name="Maximum rate of Axin2 protein degradation" value="0.6*mpm"/>
                <Constant symbol="K_dAx" name="Michaelis constant for Axin2 protein degradation" value="0.63"/>
                <Constant symbol="teta" name="scaling factor for the Wnt loop" value="1.12"/>
                <Annotation>ODEs for the Wnt Loop</Annotation>
            </System>
            <Property symbol="Wnt" value="C_12w*mFgf"/>
            <Constant symbol="C_12w" name="Factor relating Wnt concentration and fgf mRNA concentration" value="0.32"/>
            <System time-step="1.0" name="Wnt decay" solver="Euler [fixed, O(1)]">
                <Rule symbol-ref="Wnt">
                    <Expression>C_12w*mFgf</Expression>
                    <Annotation>Equation for Wnt degredation</Annotation>
                </Rule>
            </System>
            <Mapper time-step="1.0" name="Sense FGF8 at cell center">
                <Input value="if((space.x-1&lt;=cell.center.x &amp;&amp; space.x+1>=cell.center.x &amp;&amp; space.y-1&lt;=cell.center.y &amp;&amp; space.y+1>=cell.center.y),FGF,0)"/>
                <Output symbol-ref="FGF_center" mapping="maximum"/>
            </Mapper>
            <ChangeCellType newCellType="preCore" name="to preCore">
                <Condition>(FGF_center &lt; fdTh)*(FGF_center > 0.000001)*(B>bdTh)</Condition>
                <Annotation>Change cell type as soon as a threshold of fgf concentration is reached. If the beta catenenin concentration is above another threshold, the PSM cell differentiates to a pre_core cell.</Annotation>
            </ChangeCellType>
            <ChangeCellType newCellType="preEphrinB2" name="to preEphrinB2">
                <Condition>(FGF_center &lt; fdTh)*(FGF_center > 0.000001)*(B&lt;=bdTh)*(F&lt;=A*aPre)</Condition>
                <Annotation>Change cell type as soon as a threshold of fgf concentration is reached. If the beta catenenin concentration is below another threshold, and the Axin2 concentration times a factor is bigger or equal to the Lfng concentrentration  the PSM cell differentiates to a pre_EphrinBB2 cell.</Annotation>
            </ChangeCellType>
            <ChangeCellType newCellType="preEphA4" name="to preEphA4">
                <Condition>(FGF_center &lt; fdTh)*(FGF_center > 0.000001)*(B&lt;=bdTh)*(F>A*aPre)</Condition>
                <Annotation>Change cell type as soon as a threshold of fgf concentration is reached. If the beta catenenin concentration is below another threshold, and the Axin2 concentration times a factor is smaller than the Lfng concentrentration  the PSM cell differentiates to a pre_EphA4 cell.</Annotation>
            </ChangeCellType>
        </CellType>
        <CellType name="Medium" class="medium">
            <Constant symbol="mFgf" value="0"/>
            <Constant symbol="F" name="lunatic fringe protein" value="0"/>
        </CellType>
    </CellTypes>
    <CPM>
        <Interaction>
            <Contact type2="Medium" type1="Medium" value="0.0"/>
            <Contact type2="PSM" type1="Medium" value="15.0"/>
            <Contact type2="Source" type1="Medium" value="0.0"/>
            <Contact type2="preEphA4" type1="Medium" value="15.0"/>
            <Contact type2="preEphrinB2" type1="Medium" value="15.0"/>
            <Contact type2="preCore" type1="Medium" value="15.0"/>
            <Contact type2="EphA4" type1="Medium" value="5.0"/>
            <Contact type2="EphrinB2" type1="Medium" value="5.0"/>
            <Contact type2="Core" type1="Medium" value="15.0"/>
            <Contact type2="Wall" type1="Medium" value="0.0"/>
            <Contact type2="Wall_Off" type1="Medium" value="100"/>
            <Contact type2="PSM" type1="PSM" value="-20.0"/>
            <Contact type2="Source" type1="PSM" value="-20.0"/>
            <Contact type2="preEphA4" type1="PSM" value="-20.0"/>
            <Contact type2="preEphrinB2" type1="PSM" value="-20.0"/>
            <Contact type2="preCore" type1="PSM" value="-20.0"/>
            <Contact type2="EphA4" type1="PSM" value="-20.0"/>
            <Contact type2="EphrinB2" type1="PSM" value="-20.0"/>
            <Contact type2="Core" type1="PSM" value="-20.0"/>
            <Contact type2="Wall" type1="PSM" value="30.0"/>
            <Contact type2="Wall_Off" type1="PSM" value="100"/>
            <Contact type2="preEphA4" type1="Source" value="-20.0"/>
            <Contact type2="preEphrinB2" type1="Source" value="-20.0"/>
            <Contact type2="preCore" type1="Source" value="-20.0"/>
            <Contact type2="EphA4" type1="Source" value="-20.0"/>
            <Contact type2="EphrinB2" type1="Source" value="-20.0"/>
            <Contact type2="Core" type1="Source" value="-20.0"/>
            <Contact type2="Wall" type1="Source" value="30.0"/>
            <Contact type2="Wall_Off" type1="Source" value="100"/>
            <Contact type2="Source" type1="Source" value="-20.0"/>
            <Contact type2="preEphA4" type1="preEphA4" value="-25.0"/>
            <Contact type2="preEphrinB2" type1="preEphA4" value="-20.0"/>
            <Contact type2="preCore" type1="preEphA4" value="-20.0"/>
            <Contact type2="EphA4" type1="preEphA4" value="-25.0"/>
            <Contact type2="EphrinB2" type1="preEphA4" value="-20.0"/>
            <Contact type2="Core" type1="preEphA4" value="-20.0"/>
            <Contact type2="Wall" type1="preEphA4" value="30.0"/>
            <Contact type2="Wall_Off" type1="preEphA4" value="100"/>
            <Contact type2="preEphrinB2" type1="preEphrinB2" value="-25.0"/>
            <Contact type2="preCore" type1="preEphrinB2" value="-20.0"/>
            <Contact type2="EphA4" type1="preEphrinB2" value="-20.0"/>
            <Contact type2="EphrinB2" type1="preEphrinB2" value="-25.0"/>
            <Contact type2="Core" type1="preEphrinB2" value="-20.0"/>
            <Contact type2="Wall" type1="preEphrinB2" value="30.0"/>
            <Contact type2="Wall_Off" type1="preEphrinB2" value="100"/>
            <Contact type2="preCore" type1="preCore" value="-35.0"/>
            <Contact type2="EphA4" type1="preCore" value="-20.0"/>
            <Contact type2="EphrinB2" type1="preCore" value="-20.0"/>
            <Contact type2="Core" type1="preCore" value="-20.0"/>
            <Contact type2="Wall" type1="preCore" value="30.0"/>
            <Contact type2="Wall_Off" type1="preCore" value="100"/>
            <Contact type2="EphA4" type1="EphA4" value="-25.0"/>
            <Contact type2="EphrinB2" type1="EphA4" value="80.0"/>
            <Contact type2="Core" type1="EphA4" value="-25.0"/>
            <Contact type2="Wall" type1="EphA4" value="30.0"/>
            <Contact type2="Wall_Off" type1="EphA4" value="100"/>
            <Contact type2="EphrinB2" type1="EphrinB2" value="-25.0"/>
            <Contact type2="Core" type1="EphrinB2" value="-25.0"/>
            <Contact type2="Wall" type1="EphrinB2" value="30.0"/>
            <Contact type2="Wall_Off" type1="EphrinB2" value="100"/>
            <Contact type2="Core" type1="Core" value="-40.0"/>
            <Contact type2="Wall" type1="Core" value="30.0"/>
            <Contact type2="Wall_Off" type1="Core" value="100"/>
            <Contact type2="Wall" type1="Wall" value="0.0"/>
            <Contact type2="Wall_Off" type1="Wall" value="100"/>
            <Contact type2="Wall_Off" type1="Wall_Off" value="100"/>
        </Interaction>
        <ShapeSurface scaling="classic">
            <Neighborhood>
                <Order>2</Order>
            </Neighborhood>
        </ShapeSurface>
        <MonteCarloSampler stepper="edgelist">
            <MCSDuration value="1"/>
            <MetropolisKinetics temperature="120"/>
            <Neighborhood>
                <Order>4</Order>
            </Neighborhood>
        </MonteCarloSampler>
    </CPM>
    <CellPopulations>
        <Population type="Wall" name="Two columns of Wall cells" size="0">
            <InitCellObjects mode="distance">
                <Arrangement repetitions="2, size.y/wall, 0" displacements="cD*11, wall, 0">
                    <Box origin="margin, 0.0, 0.0" size="wall,wall, 0.0"/>
                </Arrangement>
            </InitCellObjects>
        </Population>
        <Population type="PSM" name="PSM tissue" size="0">
            <InitCellObjects mode="distance">
                <Arrangement repetitions="10, 3, 0" displacements="cD, cD, 0">
                    <Box origin="margin + wall, size.y-18-4*cD, 0.0" size="cD, cD, 0.0"/>
                </Arrangement>
            </InitCellObjects>
        </Population>
        <Population type="Source" name="Source cell layer" size="0">
            <InitCellObjects mode="distance">
                <Arrangement repetitions="10, 1, 0" displacements="cD, 0, 0">
                    <Box origin="margin + wall, size.y-24-4*cD, 0.0" size="cD, cD, 0.0"/>
                </Arrangement>
            </InitCellObjects>
        </Population>
    </CellPopulations>
    <Global>
        <Constant symbol="cD" name="Cell diameter" value="7">
            <Annotation>Default cell diameter</Annotation>
        </Constant>
        <Constant symbol="tS" name="Target surface" value="28">
            <Annotation>Default target surface</Annotation>
        </Constant>
        <Constant symbol="LamS" name="Surface strength" value="15">
            <Annotation>Default weight for CPM surface constraint, termed lambda_s in Hester et al. 2011</Annotation>
        </Constant>
        <Constant symbol="LamV" name="Volume strength" value="15">
            <Annotation>Default weight for CPM volume constraint, termed lambda_v in Hester et al. 2011</Annotation>
        </Constant>
        <Constant symbol="tV" name="Target volume" value="cD*cD"/>
        <Constant symbol="margin" name="Margin" value="35">
            <Annotation>Number of empty lattice nodes between wall cells and lattice boundary</Annotation>
        </Constant>
        <Constant symbol="wall" name="Wall cell diameter" value="7">
            <Annotation>Width of the two columns made by Wall cells</Annotation>
        </Constant>
        <Constant symbol="slopeFGF" name="Initial slope of FGF8 gradient" value="(45-39.6)/(cD*4)">
            <Annotation>Initial slope of FGF8 gradient (used for initializing FGF field) computed as the value of FGF (from Hester et al. 2011, page 13 bottom right) at the posterior end (45nM) minus the value of FGF at the fourth cell layer (39.6 nM) divided by the thickness of 4 cell layers.</Annotation>
        </Constant>
        <Field symbol="FGF" value="if((size.y-4*cD-space.y &lt;= cD*4 +3)*(size.y-4*cD-space.y>0)*(space.x >= margin + wall)*(space.x &lt;= margin+ wall + 10*cD), 39.6 + slopeFGF*(size.y-4*cD-space.y), 0)">
            <Diffusion rate="0.6*0.7*0.7*mpm"/>
            <Annotation>Initialization of FGF8 gradient and diffusion term (units were rescaled from µm^2/min to pixel^2/MCS) as defined in Hester et al., 2011</Annotation>
        </Field>
        <System time-step="1" name="FGF gradient formation" solver="Heun [fixed, O(2)]">
            <DiffEqn symbol-ref="FGF">
                <Expression>-k_FGF_global*FGF + s_FGF*mFgf</Expression>
            </DiffEqn>
            <Constant symbol="k_FGF_global" name="FGF decay rate" value="0.2*mpm"/>
            <Constant symbol="s_FGF" name="FGF secretion rate (gets multiplied by FGF mRNA from Source and PSM cells, hence becomes 0 elsewhere)" value="1.83*mpm"/>
        </System>
        <Constant symbol="mpm" name="Time unit of 0.015 min per 1 Monte Carlo step (MCS)" value="0.015">
            <Annotation>Rates (and time scale of diffusion coefficient) were given in 1/min and need to be rescaled into 1/MCS using "1 MCS=mpm min -> 1 min=1/mpm MCS and 1/min = mpm 1/MCS" hence rates have been multiplied by mpm.</Annotation>
        </Constant>
        <Constant symbol="k_fgf_cell" name="Decay rate of FGF8 in PSM cells" value="0.005*mpm"/>
        <Constant symbol="DL_m" name="Background Delta expression of passive cells (Wall)" value="0.0"/>
        <Constant symbol="fdTh" name="FGF8 determination threshold" value="13.9"/>
        <Constant symbol="bdTh" name="Beta catenin determination threshold" value="0.406"/>
        <Constant symbol="aPre" name="Prefactor for Axin2 for determination threshold" value="21.28"/>
        <Variable symbol="wallDeath" value="size.y + 10">
            <Annotation>System-wide variable that specifies where somites have already formed, i.e. where the wall can disappear. Initialized with value outside of the lattice to maintain wall initially.</Annotation>
        </Variable>
        <Constant symbol="gR" name="Growth rate of target volume in source cells" value="0.12">
            <Annotation> As specified in the code in Hester's Dissertation ("Grow=0.120" on page 129)</Annotation>
        </Constant>
    </Global>
</MorpheusModel>
