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<?xml version='1.0'?>
<!-- This CellML file was generated from:
 Ostby, Ivar, et al. "Astrocytic mechanisms explaining neural-activity-induced shrinkage of extraneuronal space." PLoS Comput Biol 5.1 (2009): e1000272.-->
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    <import xlink:href="Units/Units.cellml">
        <units name="mM" units_ref="mM"/>
        <units name="mM_per_s" units_ref="mM_per_s"/>
    </import>
    <import xlink:href="Ostby_2009_NBC.cellml">
        <component component_ref="NBC" name="NBC"/>
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    <component name="environment">
        <variable name="time" public_interface="out" units="second"/>
    </component>
    <component name="concentrations">
        <variable name="time" public_interface="in" units="second"/>
        <variable initial_value="-0.032" name="V_m" public_interface="out" units="volt"/>
        <variable initial_value="15.0" name="Na_int" public_interface="out" units="mM"/>
        <variable initial_value="146.0" name="Na_ext" public_interface="out" units="mM"/>
        <variable initial_value="9.0" name="HCO3_int" public_interface="out" units="mM"/>
        <variable initial_value="15.0" name="HCO3_ext" public_interface="out" units="mM"/>
        <math xmlns="http://www.w3.org/1998/Math/MathML">
            <apply>
                <eq/>
                <apply>
                    <diff/>
                    <bvar>
                        <ci>time</ci>
                    </bvar>
                    <ci>Na_int</ci>
                </apply>
                <cn cellml:units="mM_per_s">1.0</cn>
            </apply>
        </math>
    </component>
    <component name="fluxes">
        <variable name="J_NBC_Na" public_interface="in" units="mM_per_s"/>
        <variable name="J_NBC_HCO3" public_interface="in" units="mM_per_s"/>
    </component>
    <connection>
        <map_components component_1="concentrations" component_2="NBC"/>
        <map_variables variable_1="Na_int" variable_2="Na_int"/>
        <map_variables variable_1="Na_ext" variable_2="Na_ext"/>
        <map_variables variable_1="HCO3_int" variable_2="HCO3_int"/>
        <map_variables variable_1="HCO3_ext" variable_2="HCO3_ext"/>
        <map_variables variable_1="V_m" variable_2="V_m"/>
    </connection>
    <connection>
        <map_components component_1="fluxes" component_2="NBC"/>
        <map_variables variable_1="J_NBC_Na" variable_2="J_NBC_Na"/>
        <map_variables variable_1="J_NBC_HCO3" variable_2="J_NBC_HCO3"/>
    </connection>
    <connection>
        <map_components component_1="concentrations" component_2="environment"/>
        <map_variables variable_1="time" variable_2="time"/>
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</model>