Location: Katsnelson, Nikitina, Chemla, Solovyova, Coirault, Lecarpentier, Markhasin, 2004 @ b0f02eee7dc1 / Katsnelson et al JTB 2004, seconds, dimensional.cellml

Author:
Catherine Lloyd <c.lloyd@auckland.ac.nz>
Date:
2009-09-29 12:47:24+13:00
Desc:
Added namespace for metadata
Permanent Source URI:
https://models.cellml.org/workspace/katsnelson_nikitina_chemla_solovyova_coirault_lecarpentier_markhasin_2004/rawfile/b0f02eee7dc1a2e68d60d1fcddd6ff953cb29c11/Katsnelson et al JTB 2004, seconds, dimensional.cellml

<?xml version="1.0" encoding="utf-8"?>
<!--
This CellML file was generated on 14.09.2009 at 23:59:21 using:

COR (0.9.31.1319)
Copyright 2002-2009 Dr Alan Garny
http://cor.physiol.ox.ac.uk/ - cor@physiol.ox.ac.uk

CellML 1.0 was used to generate this model
http://www.cellml.org/
-->
<model xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:bqs="http://www.cellml.org/bqs/1.0#" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:vCard="http://www.w3.org/2001/vcard-rdf/3.0#" name="katsnelson_et_al_2004" cmeta:id="katsnelson_et_al_2004" xmlns="http://www.cellml.org/cellml/1.0#" xmlns:cellml="http://www.cellml.org/cellml/1.0#" xmlns:cmeta="http://www.cellml.org/metadata/1.0#">
   
   <documentation xmlns="http://cellml.org/tmp-documentation">
		<article>
			<articleinfo>
				<title>Influence of viscosity on myocardium mechanical activity: a mathematical model</title>
				<author>
					<firstname>Geoffrey</firstname>
					<surname>Nunns</surname>
					<affiliation>
						<shortaffil>Bioengineering Institute, The University of Auckland</shortaffil>
					</affiliation>
				</author>
			</articleinfo>
			<section id="sec_status">
				<title>Model Status</title>
				<para>
        This model has been checked and it runs in both COR and PCEnv to recreate the published results. Units are consistent throughout.  In this particular version of the model, time is expressed in seconds and all calcium variables and parameters are in absolute values.        
          </para>
		  <para>
		  With default setting the model produce isometric contraction (parameter isotonic=0). To switch from isomentric mode to isotonic mode isotonic parameter should be set 1. Then set parameter F_afterload to the value less then the maximum force calculated at isometric mode. Make sure that the model is run in isometric mode first and see the value of the maximum of isometric force. If F_afterload is not less than this value, model performs isometric mode instead of isotonic.
          </para>
			</section>
			<sect1 id="sec_structure">
				<title>Model Structure</title>
				<para>
Abstract: We have previously proposed and validated a mathematical model of myocardium contraction-relaxation cycle based on current knowledge of regulatory role of Ca2+ and cross-bridge kinetics in cardiac cell. That model did not include viscous elements. Here we propose a modification of the model, in which two viscous elements are added, one in parallel to the contractile element, and one more in parallel to the series elastic element. The modified model allowed us to simulate and explain some subtle experimental data on relaxation velocity in isotonic twitches and on a mismatch between the time course of sarcomere shortening/lengthening and the time course of active force generation in isometric twitches. Model results were compared with experimental data obtained from 28 rat LV papillary muscles contracting and relaxing against various loads. Additional model analysis suggested contribution of viscosity to main inotropic and lusitropic characteristics of myocardium performance.   
</para>
				<para>
					<informalfigure float="0" id="fig_reaction_diagram">
						<mediaobject>
							<imageobject>
								<objectinfo>
									<title>model diagram</title>
								</objectinfo>
								<imagedata fileref="katsnelson_2004.png"/>
							</imageobject>
						</mediaobject>
						<caption>Schematic diagram of the Katsnelson et al model - an updated rheological scheme of the heart muscle including
contractile element CE, two passive elastic elements PE (parallel one) and SE (series one) and two viscous elements VS1 and VS2. The effect of calcium and the calcium binding ligand (B) in facilitating actin-myosin binding is also highlighted.</caption>
					</informalfigure>
				</para>
				<para>
The complete original paper reference is cited below:
</para>
				<para>
					Influence of viscosity on myocardium mechanical activity: a mathematical model, Leonid B. Katsnelson, Larissa V. Nikitina, Denis Chemla, Olga Solovyova, Catherine Coirault, Yves Lecarpentier and Vladimir S. Markhasin, 2004,
						<emphasis>Journal of Theoretical Biology</emphasis>, 230, 385-485.  <ulink url="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&amp;db=PubMed&amp;list_uids=15302547&amp;dopt=Abstract">PubMed ID: 15302547     </ulink>
				</para>
			</sect1>
		</article>
	</documentation>
	
	<rdf:RDF>
		<rdf:Seq rdf:about="rdf:#edd290fd-de23-4ec1-b5c1-4ad92741f561">
			<rdf:li rdf:resource="rdf:#b7e37085-15d0-4095-ab26-914877d77498"/>
			<rdf:li rdf:resource="rdf:#3f822535-dbd8-449a-a09d-8386592ee27d"/>
			<rdf:li rdf:resource="rdf:#7cf93199-6787-4b80-9eb1-d953e4ad54d9"/>
			<rdf:li rdf:resource="rdf:#c53c5039-770d-4100-aba8-6a3306988dab"/>
			<rdf:li rdf:resource="rdf:#082af15a-ea22-40e3-9c60-9ed939bad185"/>
			<rdf:li rdf:resource="rdf:#3c9d2952-aac4-400b-be04-f19d626b81c3"/>
			<rdf:li rdf:resource="rdf:#5c54917b-f474-4e9f-a443-bcfb360ac686"/>
		</rdf:Seq>
		<rdf:Description rdf:about="rdf:#c53c5039-770d-4100-aba8-6a3306988dab">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#eaf42a79-ba32-41ac-9b1a-c827a042bd19"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#d942f499-6045-4dbc-94d7-1d95d51628c3">
			<dc:creator rdf:resource="rdf:#243c9d21-1989-414e-b3ea-b4554f4be6ed"/>
			<rdf:value>This model runs in PCEnv, but does not recreate the published results. Units are consistent throughout.</rdf:value>
		</rdf:Description>
		<rdf:Description rdf:about="">
			<dc:publisher/>
			<cmeta:comment xmlns:cmeta="http://www.cellml.org/metadata/1.0#" rdf:resource="rdf:#1d3ec125-676c-4f64-9780-9dec442a2ee1"/>
			<dcterms:created rdf:resource="rdf:#3ed98b9f-a45e-44fc-8ef3-a66076176b2f"/>
			<dc:creator rdf:resource="rdf:#890a545d-f012-4f7c-ac05-094710c42c09"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#082af15a-ea22-40e3-9c60-9ed939bad185">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#82faf1f8-df66-4646-8681-681e83fc2920"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#26625cf7-b781-42be-a46d-3ab34002434c">
			<dc:title>Journal of Theoretical Biology</dc:title>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#7dc01a73-ec48-4d1c-9b00-cd8ac3c38da0">
			<bqs:Pubmed_id>15302547</bqs:Pubmed_id>
			<bqs:JournalArticle rdf:resource="rdf:#54cbbe1a-f9e6-410e-a09e-c3265f856c59"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#5c54917b-f474-4e9f-a443-bcfb360ac686">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#a6038160-96dd-408d-8175-7ce58ab3bbd9"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#b7e37085-15d0-4095-ab26-914877d77498">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#a18d7e3d-01f1-448a-8640-46c1d50f8d52"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#7cf93199-6787-4b80-9eb1-d953e4ad54d9">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#13ab787a-968a-4ca1-9c91-b67aa5292762"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#3c9d2952-aac4-400b-be04-f19d626b81c3">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#479cc7f2-261c-48a7-8a56-690066697521"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#3ed98b9f-a45e-44fc-8ef3-a66076176b2f">
			<dcterms:W3CDTF>2008-07-17T00:00:00+12:00</dcterms:W3CDTF>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#890a545d-f012-4f7c-ac05-094710c42c09">
			<vCard:ORG rdf:resource="rdf:#91ad59e8-ad0f-4d55-b14e-c3113907c39e"/>
			<vCard:EMAIL rdf:resource="rdf:#db3bc023-0337-4389-8685-36eaba9ca536"/>
			<vCard:N rdf:resource="rdf:#47bb5b5a-7ed4-405b-88a5-3f64926e56aa"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#a6cc2bf7-59f3-45e0-87e1-44505f54ae20">
			<vCard:FN>Geoff Nunns</vCard:FN>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#54cbbe1a-f9e6-410e-a09e-c3265f856c59">
			<dc:creator rdf:resource="rdf:#edd290fd-de23-4ec1-b5c1-4ad92741f561"/>
			<dc:title>Influence of viscosity on myocardium mechanical activity: a mathematical model</dc:title>
			<bqs:volume>230</bqs:volume>
			<bqs:first_page>385</bqs:first_page>
			<bqs:Journal rdf:resource="rdf:#26625cf7-b781-42be-a46d-3ab34002434c"/>
			<dcterms:issued rdf:resource="rdf:#840515cb-cecf-4839-aec0-a263c94219db"/>
			<bqs:last_page>405</bqs:last_page>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#1d3ec125-676c-4f64-9780-9dec442a2ee1">
			<dc:creator rdf:resource="rdf:#a6cc2bf7-59f3-45e0-87e1-44505f54ae20"/>
			<rdf:value>This model runs in PCEnv, but does not recreate the published results. Units are consistent throughout.</rdf:value>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#13ab787a-968a-4ca1-9c91-b67aa5292762">
			<vCard:Given>Denis </vCard:Given>
			<vCard:Family>Chemla</vCard:Family>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#db3bc023-0337-4389-8685-36eaba9ca536">
			<rdf:type rdf:resource="http://imc.org/vCard/3.0#internet"/>
			<rdf:value>gnunns1@jhem.jhu.edu</rdf:value>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#243c9d21-1989-414e-b3ea-b4554f4be6ed">
			<vCard:FN>Geoff Nunns</vCard:FN>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#82faf1f8-df66-4646-8681-681e83fc2920">
			<vCard:Given>Catherine </vCard:Given>
			<vCard:Family>Coirault</vCard:Family>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#c2dc8317-7436-4562-89d2-94c1e58601f9">
			<vCard:Given>Larissa</vCard:Given>
			<vCard:Family>Nikitina</vCard:Family>
			<vCard:Other>V</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#840515cb-cecf-4839-aec0-a263c94219db">
			<dcterms:W3CDTF>2004-00-00 00:00</dcterms:W3CDTF>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#479cc7f2-261c-48a7-8a56-690066697521">
			<vCard:Given>Yves </vCard:Given>
			<vCard:Family>Lecarpentier</vCard:Family>
		</rdf:Description>
		<rdf:Description rdf:about="#katsnelson_et_al_2004">
			<bqs:reference rdf:resource="rdf:#7dc01a73-ec48-4d1c-9b00-cd8ac3c38da0"/>
			<cmeta:comment xmlns:cmeta="http://www.cellml.org/metadata/1.0#" rdf:resource="rdf:#d942f499-6045-4dbc-94d7-1d95d51628c3"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#3f822535-dbd8-449a-a09d-8386592ee27d">
			<rdf:type rdf:resource="http://www.cellml.org/bqs/1.0#Person"/>
			<vCard:N rdf:resource="rdf:#c2dc8317-7436-4562-89d2-94c1e58601f9"/>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#47bb5b5a-7ed4-405b-88a5-3f64926e56aa">
			<vCard:Given>Geoffrey</vCard:Given>
			<vCard:Family>Nunns</vCard:Family>
			<vCard:Other>Rogan</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#a6038160-96dd-408d-8175-7ce58ab3bbd9">
			<vCard:Given>Vladimir </vCard:Given>
			<vCard:Family>Markhasin</vCard:Family>
			<vCard:Other>S</vCard:Other>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#eaf42a79-ba32-41ac-9b1a-c827a042bd19">
			<vCard:Given>Olga </vCard:Given>
			<vCard:Family>Solovyova</vCard:Family>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#91ad59e8-ad0f-4d55-b14e-c3113907c39e">
			<vCard:Orgname>Auckland Bioengineering Institute</vCard:Orgname>
			<vCard:Orgunit>CellML Team</vCard:Orgunit>
		</rdf:Description>
		<rdf:Description rdf:about="rdf:#a18d7e3d-01f1-448a-8640-46c1d50f8d52">
			<vCard:Given>Leonid</vCard:Given>
			<vCard:Family>Katsnelson</vCard:Family>
			<vCard:Other>B</vCard:Other>
		</rdf:Description>
		
		<!--
        The Modification History metadata. This lists the changes that have been
        made to the document, who made the changes, and when they were made.
      -->
	  <rdf:Description rdf:about="">
      <cmeta:modification rdf:parseType="Resource">
        <rdf:value>
          Extensively edited the model such that it now runs correctly to reproduce the published results
        </rdf:value>
        <cmeta:modifier rdf:parseType="Resource">
          <vCard:N rdf:parseType="Resource">
            <vCard:Family>Solovyova</vCard:Family>
            <vCard:Given>Olga</vCard:Given>
          </vCard:N>
        </cmeta:modifier>
		<vCard:EMAIL rdf:parseType="Resource">
          <rdf:value>o.solovyova@iip.uran.ru</rdf:value>
          <rdf:type rdf:resource="http://imc.org/vCard/3.0#internet"/>
        </vCard:EMAIL>
        <dcterms:modified rdf:parseType="Resource"> 
          <dcterms:W3CDTF>2009-09-28</dcterms:W3CDTF>
        </dcterms:modified>
      </cmeta:modification>
	  </rdf:Description>
	</rdf:RDF>
   
   <units name="per_second">
      <unit units="second" exponent="-1"/>
   </units>
   <units name="per_second2">
      <unit units="second" exponent="-2"/>
   </units>
   <units name="micrometre">
      <unit units="meter" prefix="micro"/>
   </units>
   <units name="micrometre_per_second">
      <unit units="micrometre"/>
      <unit units="per_second"/>
   </units>
   <units name="micrometre_per_second2">
      <unit units="micrometre"/>
      <unit units="per_second2"/>
   </units>
   <units name="per_micrometre">
      <unit units="micrometre" exponent="-1"/>
   </units>
   <units name="second_per_micrometre">
      <unit units="second"/>
      <unit units="per_micrometre"/>
   </units>
   <units name="millinewton">
      <unit units="newton" prefix="milli"/>
   </units>
   <units name="millinewton_per_second">
      <unit units="millinewton"/>
      <unit units="per_second"/>
   </units>
   <units name="millinewton_second_per_micrometre">
      <unit units="millinewton"/>
      <unit units="second_per_micrometre"/>
   </units>
   <units name="micromole">
      <unit units="mole" prefix="micro"/>
   </units>
   <units name="micromole_per_second">
      <unit units="micromole"/>
      <unit units="per_second"/>
   </units>
   <units name="per_micromole">
      <unit units="micromole" exponent="-1"/>
   </units>
   <units name="per_second_micromole">
      <unit units="per_second"/>
      <unit units="per_micromole"/>
   </units>
   <component name="environment">
      <variable name="time" units="second" public_interface="out"/>
   </component>
   <component name="parameters">
      <variable name="isotonic" units="dimensionless" initial_value="0" public_interface="out"/>
      <variable name="alpha_1" units="per_micrometre" initial_value="19" public_interface="out"/>
      <variable name="beta_1" units="millinewton" initial_value="0.29" public_interface="out"/>
      <variable name="alpha_2" units="per_micrometre" initial_value="14.6" public_interface="out"/>
      <variable name="beta_2" units="millinewton" initial_value="0.000924" public_interface="out"/>
      <variable name="alpha_3" units="per_micrometre" initial_value="48" public_interface="out"/>
      <variable name="beta_3" units="millinewton" initial_value="0.01" public_interface="out"/>
      <variable name="lambda" units="millinewton" initial_value="96" public_interface="out"/>
      <variable name="A_half" units="micromole" initial_value="42" public_interface="out"/>
      <variable name="mu" units="dimensionless" initial_value="3" public_interface="out"/>
      <variable name="chi" units="dimensionless" initial_value="0.705" public_interface="out"/>
      <variable name="chi_0" units="dimensionless" initial_value="3" public_interface="out"/>
      <variable name="m_0" units="dimensionless" initial_value="0.9" public_interface="out"/>
      <variable name="v_max" units="micrometre_per_second" initial_value="5.6" public_interface="out"/>
      <variable name="a" units="dimensionless" initial_value="0.25" public_interface="out"/>
      <variable name="d_h" units="dimensionless" initial_value="0.5" public_interface="out"/>
      <variable name="alpha_P" units="dimensionless" initial_value="4" public_interface="out"/>
   </component>
   <component name="isotonic">
      <variable name="time" units="second" public_interface="in"/>
      <variable name="isotonic" units="dimensionless" public_interface="in"/>
      <variable name="l" units="micrometre" public_interface="in"/>
      <variable name="F_muscle" units="millinewton" public_interface="in"/>
      <variable name="flag" units="dimensionless"/>
      <variable name="F_afterload" units="millinewton" initial_value="2"/>
      <variable name="isotonic_mode" units="dimensionless" public_interface="out"/>
      <variable name="l_0" units="micrometre" initial_value="0.527"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>flag</ci>
            <piecewise>
               <piece>
                  <cn cellml:units="dimensionless">0</cn>
                  <apply>
                     <and/>
                     <apply>
                        <geq/>
                        <ci>l</ci>
                        <ci>l_0</ci>
                     </apply>
                     <apply>
                        <lt/>
                        <ci>time</ci>
                        <cn cellml:units="second">0.15</cn>
                     </apply>
                  </apply>
               </piece>
               <otherwise>
                  <cn cellml:units="dimensionless">1</cn>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>isotonic_mode</ci>
            <piecewise>
               <piece>
                  <cn cellml:units="dimensionless">0</cn>
                  <apply>
                     <eq/>
                     <ci>isotonic</ci>
                     <cn cellml:units="dimensionless">0</cn>
                  </apply>
               </piece>
               <piece>
                  <cn cellml:units="dimensionless">1</cn>
                  <apply>
                     <and/>
                     <apply>
                        <eq/>
                        <ci>isotonic</ci>
                        <cn cellml:units="dimensionless">1</cn>
                     </apply>
                     <apply>
                        <geq/>
                        <ci>F_muscle</ci>
                        <ci>F_afterload</ci>
                     </apply>
                  </apply>
               </piece>
               <piece>
                  <cn cellml:units="dimensionless">0</cn>
                  <apply>
                     <and/>
                     <apply>
                        <eq/>
                        <ci>isotonic</ci>
                        <cn cellml:units="dimensionless">1</cn>
                     </apply>
                     <apply>
                        <geq/>
                        <ci>l</ci>
                        <ci>l_0</ci>
                     </apply>
                     <apply>
                        <eq/>
                        <ci>flag</ci>
                        <cn cellml:units="dimensionless">1</cn>
                     </apply>
                  </apply>
               </piece>
            </piecewise>
         </apply>
      </math>
   </component>
   <component name="parameters_izakov_et_al_1991">
      <variable name="S_0" units="micrometre" initial_value="1.14" public_interface="out"/>
      <variable name="q_v" units="per_second" public_interface="out"/>
      <variable name="q_1" units="per_second" initial_value="17.3"/>
      <variable name="q_2" units="per_second" initial_value="259"/>
      <variable name="q_3" units="per_second" initial_value="17.3"/>
      <variable name="q_4" units="per_second" initial_value="15" public_interface="out"/>
      <variable name="v_star" units="micrometre_per_second" initial_value="5.3035675" public_interface="out"/>
      <variable name="v_1" units="micrometre_per_second" public_interface="out"/>
      <variable name="alpha_G" units="dimensionless" initial_value="1" public_interface="out"/>
      <variable name="a_on" units="per_second_micromole" initial_value="32.85" public_interface="out"/>
      <variable name="a_off" units="per_second" initial_value="290" public_interface="out"/>
      <variable name="k_A" units="per_micromole" initial_value="0.04" public_interface="out"/>
      <variable name="v" units="micrometre_per_second" public_interface="in"/>
      <variable name="v_max" units="micrometre_per_second" public_interface="in"/>
      <variable name="alpha_Q" units="dimensionless" initial_value="10"/>
      <variable name="beta_Q" units="dimensionless" initial_value="5000"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>q_v</ci>
            <piecewise>
               <piece>
                  <apply>
                     <minus/>
                     <ci>q_1</ci>
                     <apply>
                        <divide/>
                        <apply>
                           <times/>
                           <ci>q_2</ci>
                           <ci>v</ci>
                        </apply>
                        <ci>v_max</ci>
                     </apply>
                  </apply>
                  <apply>
                     <leq/>
                     <ci>v</ci>
                     <cn cellml:units="micrometre_per_second">0</cn>
                  </apply>
               </piece>
               <piece>
                  <apply>
                     <plus/>
                     <apply>
                        <divide/>
                        <apply>
                           <times/>
                           <apply>
                              <minus/>
                              <ci>q_4</ci>
                              <ci>q_3</ci>
                           </apply>
                           <ci>v</ci>
                        </apply>
                        <ci>v_star</ci>
                     </apply>
                     <ci>q_3</ci>
                  </apply>
                  <apply>
                     <and/>
                     <apply>
                        <leq/>
                        <ci>v</ci>
                        <ci>v_star</ci>
                     </apply>
                     <apply>
                        <lt/>
                        <cn cellml:units="micrometre_per_second">0</cn>
                        <ci>v</ci>
                     </apply>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <divide/>
                     <ci>q_4</ci>
                     <apply>
                        <power/>
                        <apply>
                           <plus/>
                           <cn cellml:units="dimensionless">1</cn>
                           <apply>
                              <divide/>
                              <apply>
                                 <times/>
                                 <ci>beta_Q</ci>
                                 <apply>
                                    <minus/>
                                    <ci>v</ci>
                                    <ci>v_star</ci>
                                 </apply>
                              </apply>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                        <ci>alpha_Q</ci>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>v_1</ci>
            <apply>
               <divide/>
               <ci>v_max</ci>
               <cn cellml:units="dimensionless">10</cn>
            </apply>
         </apply>
      </math>
   </component>
   <component name="force">
      <variable name="F_CE" units="millinewton"/>
      <variable name="F_muscle" units="millinewton" public_interface="out"/>
      <variable name="F_XSE" units="millinewton"/>
      <variable name="F_SE" units="millinewton"/>
      <variable name="F_PE" units="millinewton"/>
      <variable name="N" units="dimensionless" public_interface="in"/>
      <variable name="k_P_vis" units="millinewton_second_per_micrometre" public_interface="in"/>
      <variable name="k_S_vis" units="millinewton_second_per_micrometre" public_interface="in"/>
      <variable name="w" units="micrometre_per_second" public_interface="in"/>
      <variable name="v" units="micrometre_per_second" public_interface="in"/>
      <variable name="l_1" units="micrometre" public_interface="in"/>
      <variable name="l_2" units="micrometre" public_interface="in"/>
      <variable name="l_3" units="micrometre" public_interface="in"/>
      <variable name="p_v" units="dimensionless" public_interface="in"/>
      <variable name="alpha_1" units="per_micrometre" public_interface="in"/>
      <variable name="beta_1" units="millinewton" public_interface="in"/>
      <variable name="alpha_2" units="per_micrometre" public_interface="in"/>
      <variable name="beta_2" units="millinewton" public_interface="in"/>
      <variable name="alpha_3" units="per_micrometre" public_interface="in"/>
      <variable name="beta_3" units="millinewton" public_interface="in"/>
      <variable name="lambda" units="millinewton" public_interface="in"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>F_CE</ci>
            <apply>
               <times/>
               <ci>lambda</ci>
               <ci>p_v</ci>
               <ci>N</ci>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>F_muscle</ci>
            <ci>F_XSE</ci>
         </apply>
         <apply>
            <eq/>
            <ci>F_SE</ci>
            <apply>
               <times/>
               <ci>beta_1</ci>
               <apply>
                  <minus/>
                  <apply>
                     <exp/>
                     <apply>
                        <times/>
                        <ci>alpha_1</ci>
                        <apply>
                           <minus/>
                           <ci>l_2</ci>
                           <ci>l_1</ci>
                        </apply>
                     </apply>
                  </apply>
                  <cn cellml:units="dimensionless">1</cn>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>F_PE</ci>
            <apply>
               <times/>
               <ci>beta_2</ci>
               <apply>
                  <minus/>
                  <apply>
                     <exp/>
                     <apply>
                        <times/>
                        <ci>alpha_2</ci>
                        <ci>l_2</ci>
                     </apply>
                  </apply>
                  <cn cellml:units="dimensionless">1</cn>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>F_XSE</ci>
            <apply>
               <times/>
               <ci>beta_3</ci>
               <apply>
                  <minus/>
                  <apply>
                     <exp/>
                     <apply>
                        <times/>
                        <ci>alpha_3</ci>
                        <ci>l_3</ci>
                     </apply>
                  </apply>
                  <cn cellml:units="dimensionless">1</cn>
               </apply>
            </apply>
         </apply>
      </math>
   </component>
   <component name="crossbridge_kinetics">
      <variable name="N" units="dimensionless" initial_value="0.0001" public_interface="out"/>
      <variable name="K_chi" units="per_second" public_interface="out"/>
      <variable name="M_A" units="dimensionless"/>
      <variable name="n_1" units="dimensionless"/>
      <variable name="L_oz" units="dimensionless" public_interface="out"/>
      <variable name="k_p_v" units="per_second"/>
      <variable name="k_m_v" units="per_second"/>
      <variable name="time" units="second" public_interface="in"/>
      <variable name="A" units="micromole" public_interface="in"/>
      <variable name="l_1" units="micrometre" public_interface="in"/>
      <variable name="A_half" units="micromole" public_interface="in"/>
      <variable name="mu" units="dimensionless" public_interface="in"/>
      <variable name="chi" units="dimensionless" public_interface="in"/>
      <variable name="chi_0" units="dimensionless" public_interface="in"/>
      <variable name="m_0" units="dimensionless" public_interface="in"/>
      <variable name="S_0" units="micrometre" public_interface="in"/>
      <variable name="q_v" units="per_second" public_interface="in"/>
      <variable name="v" units="micrometre_per_second" public_interface="in"/>
      <variable name="v_star" units="micrometre_per_second" public_interface="in"/>
      <variable name="G_star" units="dimensionless" public_interface="in"/>
      <variable name="P_star" units="dimensionless" public_interface="in"/>
      <variable name="q_4" units="per_second" public_interface="in"/>
      <variable name="v_0" units="micrometre_per_second" initial_value="560"/>
      <variable name="q_star" units="per_second" initial_value="1000"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>M_A</ci>
            <apply>
               <divide/>
               <apply>
                  <power/>
                  <ci>A</ci>
                  <ci>mu</ci>
               </apply>
               <apply>
                  <plus/>
                  <apply>
                     <power/>
                     <ci>A</ci>
                     <ci>mu</ci>
                  </apply>
                  <apply>
                     <power/>
                     <ci>A_half</ci>
                     <ci>mu</ci>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>n_1</ci>
            <apply>
               <plus/>
               <apply>
                  <times/>
                  <cn cellml:units="per_micrometre">0.6</cn>
                  <ci>l_1</ci>
               </apply>
               <cn cellml:units="dimensionless">0.5</cn>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>L_oz</ci>
            <apply>
               <divide/>
               <apply>
                  <plus/>
                  <ci>l_1</ci>
                  <ci>S_0</ci>
               </apply>
               <apply>
                  <plus/>
                  <cn cellml:units="micrometre">0.46</cn>
                  <ci>S_0</ci>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>k_p_v</ci>
            <apply>
               <times/>
               <ci>chi</ci>
               <ci>chi_0</ci>
               <ci>q_v</ci>
               <ci>m_0</ci>
               <ci>G_star</ci>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>k_m_v</ci>
            <piecewise>
               <piece>
                  <apply>
                     <times/>
                     <ci>chi_0</ci>
                     <ci>q_v</ci>
                     <apply>
                        <minus/>
                        <cn cellml:units="dimensionless">1</cn>
                        <apply>
                           <times/>
                           <ci>chi</ci>
                           <ci>m_0</ci>
                           <ci>G_star</ci>
                        </apply>
                     </apply>
                  </apply>
                  <apply>
                     <leq/>
                     <ci>v</ci>
                     <ci>v_star</ci>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <times/>
                     <ci>chi_0</ci>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>q_4</ci>
                           <apply>
                              <minus/>
                              <cn cellml:units="dimensionless">1</cn>
                              <apply>
                                 <times/>
                                 <ci>chi</ci>
                                 <ci>m_0</ci>
                                 <ci>G_star</ci>
                              </apply>
                           </apply>
                        </apply>
                        <apply>
                           <divide/>
                           <apply>
                              <times/>
                              <ci>q_star</ci>
                              <apply>
                                 <minus/>
                                 <ci>v</ci>
                                 <ci>v_star</ci>
                              </apply>
                           </apply>
                           <apply>
                              <minus/>
                              <ci>v_0</ci>
                              <ci>v_star</ci>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>K_chi</ci>
            <apply>
               <minus/>
               <apply>
                  <times/>
                  <ci>k_p_v</ci>
                  <ci>M_A</ci>
                  <ci>n_1</ci>
                  <ci>L_oz</ci>
                  <apply>
                     <minus/>
                     <cn cellml:units="dimensionless">1</cn>
                     <ci>N</ci>
                  </apply>
               </apply>
               <apply>
                  <times/>
                  <ci>k_m_v</ci>
                  <ci>N</ci>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>N</ci>
            </apply>
            <ci>K_chi</ci>
         </apply>
      </math>
   </component>
   <component name="length">
      <variable name="dl_1_dt" units="micrometre_per_second" public_interface="out"/>
      <variable name="l_1" units="micrometre" initial_value="0.437" public_interface="out"/>
      <variable name="dl_2_dt" units="micrometre_per_second" public_interface="out"/>
      <variable name="l_2" units="micrometre" initial_value="0.439" public_interface="out"/>
      <variable name="dl_3_dt" units="micrometre_per_second" public_interface="out"/>
      <variable name="l_3" units="micrometre" initial_value="0.089" public_interface="out"/>
      <variable name="time" units="second" public_interface="in"/>
      <variable name="isotonic_mode" units="dimensionless" public_interface="in"/>
      <variable name="v" units="micrometre_per_second" public_interface="in"/>
      <variable name="w" units="micrometre_per_second" public_interface="in"/>
      <variable name="l" units="micrometre" public_interface="out"/>
      <variable name="k_S_vis" units="millinewton_second_per_micrometre" public_interface="in"/>
      <variable name="phi_chi_2" units="micrometre_per_second" public_interface="in"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>l</ci>
            <apply>
               <plus/>
               <ci>l_2</ci>
               <ci>l_3</ci>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>dl_1_dt</ci>
            <ci>v</ci>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>l_1</ci>
            </apply>
            <ci>dl_1_dt</ci>
         </apply>
         <apply>
            <eq/>
            <ci>dl_2_dt</ci>
            <piecewise>
               <piece>
                  <ci>phi_chi_2</ci>
                  <apply>
                     <eq/>
                     <ci>k_S_vis</ci>
                     <cn cellml:units="millinewton_second_per_micrometre">0</cn>
                  </apply>
               </piece>
               <otherwise>
                  <ci>w</ci>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>l_2</ci>
            </apply>
            <ci>dl_2_dt</ci>
         </apply>
         <apply>
            <eq/>
            <ci>dl_3_dt</ci>
            <piecewise>
               <piece>
                  <cn cellml:units="micrometre_per_second">0</cn>
                  <apply>
                     <eq/>
                     <ci>isotonic_mode</ci>
                     <cn cellml:units="dimensionless">1</cn>
                  </apply>
               </piece>
               <piece>
                  <apply>
                     <minus/>
                     <ci>phi_chi_2</ci>
                  </apply>
                  <apply>
                     <and/>
                     <apply>
                        <eq/>
                        <ci>isotonic_mode</ci>
                        <cn cellml:units="dimensionless">0</cn>
                     </apply>
                     <apply>
                        <eq/>
                        <ci>k_S_vis</ci>
                        <cn cellml:units="millinewton_second_per_micrometre">0</cn>
                     </apply>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <minus/>
                     <ci>w</ci>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>l_3</ci>
            </apply>
            <ci>dl_3_dt</ci>
         </apply>
      </math>
   </component>
   <component name="CE_velocity">
      <variable name="v" units="micrometre_per_second" initial_value="0" public_interface="out"/>
      <variable name="phi_chi" units="micrometre_per_second2" public_interface="out"/>
      <variable name="phi_chi_2" units="micrometre_per_second" public_interface="out"/>
      <variable name="k_P_vis" units="millinewton_second_per_micrometre" public_interface="out"/>
      <variable name="k_S_vis" units="millinewton_second_per_micrometre" public_interface="in"/>
      <variable name="time" units="second" public_interface="in"/>
      <variable name="w" units="micrometre_per_second" public_interface="in"/>
      <variable name="K_chi" units="per_second" public_interface="in"/>
      <variable name="N" units="dimensionless" public_interface="in"/>
      <variable name="l_1" units="micrometre" public_interface="in"/>
      <variable name="dl_1_dt" units="micrometre_per_second" public_interface="in"/>
      <variable name="l_2" units="micrometre" public_interface="in"/>
      <variable name="l_3" units="micrometre" public_interface="in"/>
      <variable name="alpha_1" units="per_micrometre" public_interface="in"/>
      <variable name="beta_1" units="millinewton" public_interface="in"/>
      <variable name="alpha_2" units="per_micrometre" public_interface="in"/>
      <variable name="beta_2" units="millinewton" public_interface="in"/>
      <variable name="alpha_3" units="per_micrometre" public_interface="in"/>
      <variable name="beta_3" units="millinewton" public_interface="in"/>
      <variable name="lambda" units="millinewton" public_interface="in"/>
      <variable name="isotonic_mode" units="dimensionless" public_interface="in"/>
      <variable name="p_v" units="dimensionless" public_interface="in"/>
      <variable name="p_prime_v" units="second_per_micrometre" public_interface="in"/>
      <variable name="alpha_P_lengthening" units="per_micrometre" initial_value="16"/>
      <variable name="beta_P_lengthening" units="millinewton_second_per_micrometre" initial_value="0.0015"/>
      <variable name="alpha_P_shortening" units="per_micrometre" initial_value="16"/>
      <variable name="beta_P_shortening" units="millinewton_second_per_micrometre" initial_value="0.0015"/>
      <variable name="alp_p" units="per_micrometre"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>alp_p</ci>
            <piecewise>
               <piece>
                  <ci>alpha_P_lengthening</ci>
                  <apply>
                     <leq/>
                     <ci>v</ci>
                     <cn cellml:units="micrometre_per_second">0</cn>
                  </apply>
               </piece>
               <otherwise>
                  <ci>alpha_P_shortening</ci>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>k_P_vis</ci>
            <piecewise>
               <piece>
                  <apply>
                     <times/>
                     <ci>beta_P_lengthening</ci>
                     <apply>
                        <exp/>
                        <apply>
                           <times/>
                           <ci>alpha_P_lengthening</ci>
                           <ci>l_1</ci>
                        </apply>
                     </apply>
                  </apply>
                  <apply>
                     <leq/>
                     <ci>v</ci>
                     <cn cellml:units="micrometre_per_second">0</cn>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <times/>
                     <ci>beta_P_shortening</ci>
                     <apply>
                        <exp/>
                        <apply>
                           <times/>
                           <ci>alpha_P_shortening</ci>
                           <ci>l_1</ci>
                        </apply>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>phi_chi</ci>
            <piecewise>
               <piece>
                  <apply>
                     <divide/>
                     <apply>
                        <minus/>
                        <apply>
                           <plus/>
                           <apply>
                              <times/>
                              <ci>lambda</ci>
                              <ci>K_chi</ci>
                              <ci>p_v</ci>
                           </apply>
                           <apply>
                              <times/>
                              <ci>alp_p</ci>
                              <ci>k_P_vis</ci>
                              <apply>
                                 <power/>
                                 <ci>v</ci>
                                 <cn cellml:units="dimensionless">2</cn>
                              </apply>
                           </apply>
                           <apply>
                              <times/>
                              <ci>alpha_2</ci>
                              <ci>beta_2</ci>
                              <apply>
                                 <exp/>
                                 <apply>
                                    <times/>
                                    <ci>alpha_2</ci>
                                    <ci>l_2</ci>
                                 </apply>
                              </apply>
                              <ci>w</ci>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>lambda</ci>
                           <ci>N</ci>
                           <ci>p_prime_v</ci>
                        </apply>
                        <ci>k_P_vis</ci>
                     </apply>
                  </apply>
                  <apply>
                     <eq/>
                     <ci>isotonic_mode</ci>
                     <cn cellml:units="dimensionless">1</cn>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <divide/>
                     <apply>
                        <minus/>
                        <apply>
                           <plus/>
                           <apply>
                              <times/>
                              <ci>lambda</ci>
                              <ci>K_chi</ci>
                              <ci>p_v</ci>
                           </apply>
                           <apply>
                              <times/>
                              <ci>alp_p</ci>
                              <ci>k_P_vis</ci>
                              <apply>
                                 <power/>
                                 <ci>v</ci>
                                 <cn cellml:units="dimensionless">2</cn>
                              </apply>
                           </apply>
                           <apply>
                              <times/>
                              <apply>
                                 <plus/>
                                 <apply>
                                    <times/>
                                    <ci>alpha_2</ci>
                                    <ci>beta_2</ci>
                                    <apply>
                                       <exp/>
                                       <apply>
                                          <times/>
                                          <ci>alpha_2</ci>
                                          <ci>l_2</ci>
                                       </apply>
                                    </apply>
                                 </apply>
                                 <apply>
                                    <times/>
                                    <ci>alpha_3</ci>
                                    <ci>beta_3</ci>
                                    <apply>
                                       <exp/>
                                       <apply>
                                          <times/>
                                          <ci>alpha_3</ci>
                                          <ci>l_3</ci>
                                       </apply>
                                    </apply>
                                 </apply>
                              </apply>
                              <ci>w</ci>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>lambda</ci>
                           <ci>N</ci>
                           <ci>p_prime_v</ci>
                        </apply>
                        <ci>k_P_vis</ci>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>phi_chi_2</ci>
            <piecewise>
               <piece>
                  <apply>
                     <divide/>
                     <apply>
                        <times/>
                        <ci>alpha_1</ci>
                        <ci>beta_1</ci>
                        <apply>
                           <exp/>
                           <apply>
                              <times/>
                              <ci>alpha_1</ci>
                              <apply>
                                 <minus/>
                                 <ci>l_2</ci>
                                 <ci>l_1</ci>
                              </apply>
                           </apply>
                        </apply>
                        <ci>v</ci>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>alpha_1</ci>
                           <ci>beta_1</ci>
                           <apply>
                              <exp/>
                              <apply>
                                 <times/>
                                 <ci>alpha_1</ci>
                                 <apply>
                                    <minus/>
                                    <ci>l_2</ci>
                                    <ci>l_1</ci>
                                 </apply>
                              </apply>
                           </apply>
                        </apply>
                        <apply>
                           <times/>
                           <ci>alpha_2</ci>
                           <ci>beta_2</ci>
                           <apply>
                              <exp/>
                              <apply>
                                 <times/>
                                 <ci>alpha_2</ci>
                                 <ci>l_2</ci>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
                  <apply>
                     <eq/>
                     <ci>isotonic_mode</ci>
                     <cn cellml:units="dimensionless">1</cn>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <divide/>
                     <apply>
                        <times/>
                        <ci>alpha_1</ci>
                        <ci>beta_1</ci>
                        <apply>
                           <exp/>
                           <apply>
                              <times/>
                              <ci>alpha_1</ci>
                              <apply>
                                 <minus/>
                                 <ci>l_2</ci>
                                 <ci>l_1</ci>
                              </apply>
                           </apply>
                        </apply>
                        <ci>v</ci>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>alpha_1</ci>
                           <ci>beta_1</ci>
                           <apply>
                              <exp/>
                              <apply>
                                 <times/>
                                 <ci>alpha_1</ci>
                                 <apply>
                                    <minus/>
                                    <ci>l_2</ci>
                                    <ci>l_1</ci>
                                 </apply>
                              </apply>
                           </apply>
                        </apply>
                        <apply>
                           <times/>
                           <ci>alpha_2</ci>
                           <ci>beta_2</ci>
                           <apply>
                              <exp/>
                              <apply>
                                 <times/>
                                 <ci>alpha_2</ci>
                                 <ci>l_2</ci>
                              </apply>
                           </apply>
                        </apply>
                        <apply>
                           <times/>
                           <ci>alpha_3</ci>
                           <ci>beta_3</ci>
                           <apply>
                              <exp/>
                              <apply>
                                 <times/>
                                 <ci>alpha_3</ci>
                                 <ci>l_3</ci>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>v</ci>
            </apply>
            <piecewise>
               <piece>
                  <apply>
                     <divide/>
                     <apply>
                        <minus/>
                        <apply>
                           <times/>
                           <ci>alpha_1</ci>
                           <ci>beta_1</ci>
                           <apply>
                              <exp/>
                              <apply>
                                 <times/>
                                 <ci>alpha_1</ci>
                                 <apply>
                                    <minus/>
                                    <ci>l_2</ci>
                                    <ci>l_1</ci>
                                 </apply>
                              </apply>
                           </apply>
                           <apply>
                              <minus/>
                              <ci>phi_chi_2</ci>
                              <ci>v</ci>
                           </apply>
                        </apply>
                        <apply>
                           <plus/>
                           <apply>
                              <times/>
                              <ci>lambda</ci>
                              <ci>K_chi</ci>
                              <ci>p_v</ci>
                           </apply>
                           <apply>
                              <times/>
                              <ci>alp_p</ci>
                              <ci>k_P_vis</ci>
                              <apply>
                                 <power/>
                                 <ci>v</ci>
                                 <cn cellml:units="dimensionless">2</cn>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>lambda</ci>
                           <ci>N</ci>
                           <ci>p_prime_v</ci>
                        </apply>
                        <ci>k_P_vis</ci>
                     </apply>
                  </apply>
                  <apply>
                     <eq/>
                     <ci>k_S_vis</ci>
                     <cn cellml:units="millinewton_second_per_micrometre">0</cn>
                  </apply>
               </piece>
               <otherwise>
                  <ci>phi_chi</ci>
               </otherwise>
            </piecewise>
         </apply>
      </math>
   </component>
   <component name="PE_velocity">
      <variable name="w" units="micrometre_per_second" initial_value="0" public_interface="out"/>
      <variable name="k_S_vis" units="millinewton_second_per_micrometre" public_interface="out"/>
      <variable name="time" units="second" public_interface="in"/>
      <variable name="v" units="micrometre_per_second" public_interface="in"/>
      <variable name="phi_chi" units="micrometre_per_second2" public_interface="in"/>
      <variable name="l_1" units="micrometre" public_interface="in"/>
      <variable name="dl_1_dt" units="micrometre_per_second" public_interface="in"/>
      <variable name="l_2" units="micrometre" public_interface="in"/>
      <variable name="dl_2_dt" units="micrometre_per_second" public_interface="in"/>
      <variable name="l_3" units="micrometre" public_interface="in"/>
      <variable name="alpha_1" units="per_micrometre" public_interface="in"/>
      <variable name="beta_1" units="millinewton" public_interface="in"/>
      <variable name="alpha_2" units="per_micrometre" public_interface="in"/>
      <variable name="beta_2" units="millinewton" public_interface="in"/>
      <variable name="alpha_3" units="per_micrometre" public_interface="in"/>
      <variable name="beta_3" units="millinewton" public_interface="in"/>
      <variable name="lambda" units="millinewton" public_interface="in"/>
      <variable name="isotonic_mode" units="dimensionless" public_interface="in"/>
      <variable name="alpha_S_lengthening" units="per_micrometre" initial_value="39"/>
      <variable name="beta_S_lengthening" units="millinewton_second_per_micrometre" initial_value="0.008"/>
      <variable name="alpha_S_shortening" units="per_micrometre" initial_value="46"/>
      <variable name="beta_S_shortening" units="millinewton_second_per_micrometre" initial_value="0.006"/>
      <variable name="alp_s" units="per_micrometre"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>alp_s</ci>
            <piecewise>
               <piece>
                  <ci>alpha_S_lengthening</ci>
                  <apply>
                     <leq/>
                     <ci>w</ci>
                     <ci>v</ci>
                  </apply>
               </piece>
               <otherwise>
                  <ci>alpha_S_shortening</ci>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>k_S_vis</ci>
            <piecewise>
               <piece>
                  <apply>
                     <times/>
                     <ci>beta_S_lengthening</ci>
                     <apply>
                        <exp/>
                        <apply>
                           <times/>
                           <ci>alpha_S_lengthening</ci>
                           <apply>
                              <minus/>
                              <ci>l_2</ci>
                              <ci>l_1</ci>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
                  <apply>
                     <leq/>
                     <ci>w</ci>
                     <ci>v</ci>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <times/>
                     <ci>beta_S_shortening</ci>
                     <apply>
                        <exp/>
                        <apply>
                           <times/>
                           <ci>alpha_S_shortening</ci>
                           <apply>
                              <minus/>
                              <ci>l_2</ci>
                              <ci>l_1</ci>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>w</ci>
            </apply>
            <piecewise>
               <piece>
                  <apply>
                     <divide/>
                     <apply>
                        <minus/>
                        <apply>
                           <minus/>
                           <apply>
                              <times/>
                              <ci>k_S_vis</ci>
                              <apply>
                                 <minus/>
                                 <ci>phi_chi</ci>
                                 <apply>
                                    <times/>
                                    <ci>alp_s</ci>
                                    <apply>
                                       <power/>
                                       <apply>
                                          <minus/>
                                          <ci>w</ci>
                                          <ci>v</ci>
                                       </apply>
                                       <cn cellml:units="dimensionless">2</cn>
                                    </apply>
                                 </apply>
                              </apply>
                           </apply>
                           <apply>
                              <times/>
                              <ci>alpha_1</ci>
                              <ci>beta_1</ci>
                              <apply>
                                 <exp/>
                                 <apply>
                                    <times/>
                                    <ci>alpha_1</ci>
                                    <apply>
                                       <minus/>
                                       <ci>l_2</ci>
                                       <ci>l_1</ci>
                                    </apply>
                                 </apply>
                              </apply>
                              <apply>
                                 <minus/>
                                 <ci>w</ci>
                                 <ci>v</ci>
                              </apply>
                           </apply>
                        </apply>
                        <apply>
                           <times/>
                           <ci>alpha_2</ci>
                           <ci>beta_2</ci>
                           <apply>
                              <exp/>
                              <apply>
                                 <times/>
                                 <ci>alpha_2</ci>
                                 <ci>l_2</ci>
                              </apply>
                           </apply>
                           <ci>w</ci>
                        </apply>
                     </apply>
                     <ci>k_S_vis</ci>
                  </apply>
                  <apply>
                     <eq/>
                     <ci>isotonic_mode</ci>
                     <cn cellml:units="dimensionless">1</cn>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <minus/>
                     <apply>
                        <minus/>
                        <ci>phi_chi</ci>
                        <apply>
                           <times/>
                           <ci>alp_s</ci>
                           <apply>
                              <power/>
                              <apply>
                                 <minus/>
                                 <ci>w</ci>
                                 <ci>v</ci>
                              </apply>
                              <cn cellml:units="dimensionless">2</cn>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <divide/>
                        <apply>
                           <plus/>
                           <apply>
                              <times/>
                              <ci>alpha_1</ci>
                              <ci>beta_1</ci>
                              <apply>
                                 <exp/>
                                 <apply>
                                    <times/>
                                    <ci>alpha_1</ci>
                                    <apply>
                                       <minus/>
                                       <ci>l_2</ci>
                                       <ci>l_1</ci>
                                    </apply>
                                 </apply>
                              </apply>
                              <apply>
                                 <minus/>
                                 <ci>w</ci>
                                 <ci>v</ci>
                              </apply>
                           </apply>
                           <apply>
                              <times/>
                              <apply>
                                 <plus/>
                                 <apply>
                                    <times/>
                                    <ci>alpha_2</ci>
                                    <ci>beta_2</ci>
                                    <apply>
                                       <exp/>
                                       <apply>
                                          <times/>
                                          <ci>alpha_2</ci>
                                          <ci>l_2</ci>
                                       </apply>
                                    </apply>
                                 </apply>
                                 <apply>
                                    <times/>
                                    <ci>alpha_3</ci>
                                    <ci>beta_3</ci>
                                    <apply>
                                       <exp/>
                                       <apply>
                                          <times/>
                                          <ci>alpha_3</ci>
                                          <ci>l_3</ci>
                                       </apply>
                                    </apply>
                                 </apply>
                              </apply>
                              <ci>w</ci>
                           </apply>
                        </apply>
                        <ci>k_S_vis</ci>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
      </math>
   </component>
   <component name="average_crossbridge_force">
      <variable name="p_v" units="dimensionless" public_interface="out"/>
      <variable name="p_prime_v" units="second_per_micrometre" public_interface="out"/>
      <variable name="P_star" units="dimensionless" public_interface="out"/>
      <variable name="G_star" units="dimensionless" public_interface="out"/>
      <variable name="gamma" units="dimensionless"/>
      <variable name="case_1" units="second_per_micrometre"/>
      <variable name="case_2" units="second_per_micrometre"/>
      <variable name="case_3" units="second_per_micrometre"/>
      <variable name="case_4" units="second_per_micrometre"/>
      <variable name="v" units="micrometre_per_second" public_interface="in"/>
      <variable name="phi_chi" units="micrometre_per_second2" public_interface="in"/>
      <variable name="v_1" units="micrometre_per_second" public_interface="in"/>
      <variable name="v_max" units="micrometre_per_second" public_interface="in"/>
      <variable name="a" units="dimensionless" public_interface="in"/>
      <variable name="d_h" units="dimensionless" public_interface="in"/>
      <variable name="alpha_G" units="dimensionless" public_interface="in"/>
      <variable name="alpha_P" units="dimensionless" public_interface="in"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>gamma</ci>
            <apply>
               <divide/>
               <apply>
                  <times/>
                  <ci>a</ci>
                  <ci>d_h</ci>
                  <apply>
                     <power/>
                     <apply>
                        <divide/>
                        <ci>v_1</ci>
                        <ci>v_max</ci>
                     </apply>
                     <cn cellml:units="dimensionless">2</cn>
                  </apply>
               </apply>
               <apply>
                  <minus/>
                  <apply>
                     <times/>
                     <cn cellml:units="dimensionless">3</cn>
                     <ci>a</ci>
                     <ci>d_h</ci>
                  </apply>
                  <apply>
                     <divide/>
                     <apply>
                        <times/>
                        <apply>
                           <plus/>
                           <ci>a</ci>
                           <cn cellml:units="dimensionless">1</cn>
                        </apply>
                        <ci>v_1</ci>
                     </apply>
                     <ci>v_max</ci>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>P_star</ci>
            <piecewise>
               <piece>
                  <apply>
                     <divide/>
                     <apply>
                        <times/>
                        <ci>a</ci>
                        <apply>
                           <plus/>
                           <cn cellml:units="dimensionless">1</cn>
                           <apply>
                              <divide/>
                              <ci>v</ci>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <minus/>
                        <ci>a</ci>
                        <apply>
                           <divide/>
                           <ci>v</ci>
                           <ci>v_max</ci>
                        </apply>
                     </apply>
                  </apply>
                  <apply>
                     <leq/>
                     <ci>v</ci>
                     <cn cellml:units="micrometre_per_second">0</cn>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <minus/>
                     <apply>
                        <plus/>
                        <cn cellml:units="dimensionless">1</cn>
                        <ci>d_h</ci>
                     </apply>
                     <apply>
                        <divide/>
                        <apply>
                           <times/>
                           <apply>
                              <power/>
                              <ci>d_h</ci>
                              <cn cellml:units="dimensionless">2</cn>
                           </apply>
                           <ci>a</ci>
                        </apply>
                        <apply>
                           <plus/>
                           <apply>
                              <times/>
                              <apply>
                                 <divide/>
                                 <apply>
                                    <times/>
                                    <ci>a</ci>
                                    <ci>d_h</ci>
                                 </apply>
                                 <ci>gamma</ci>
                              </apply>
                              <apply>
                                 <power/>
                                 <apply>
                                    <divide/>
                                    <ci>v</ci>
                                    <ci>v_max</ci>
                                 </apply>
                                 <cn cellml:units="dimensionless">2</cn>
                              </apply>
                           </apply>
                           <apply>
                              <divide/>
                              <apply>
                                 <times/>
                                 <apply>
                                    <plus/>
                                    <ci>a</ci>
                                    <cn cellml:units="dimensionless">1</cn>
                                 </apply>
                                 <ci>v</ci>
                              </apply>
                              <ci>v_max</ci>
                           </apply>
                           <apply>
                              <times/>
                              <ci>a</ci>
                              <ci>d_h</ci>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>G_star</ci>
            <piecewise>
               <piece>
                  <apply>
                     <plus/>
                     <cn cellml:units="dimensionless">1</cn>
                     <apply>
                        <divide/>
                        <apply>
                           <times/>
                           <cn cellml:units="dimensionless">0.6</cn>
                           <ci>v</ci>
                        </apply>
                        <ci>v_max</ci>
                     </apply>
                  </apply>
                  <apply>
                     <and/>
                     <apply>
                        <leq/>
                        <apply>
                           <minus/>
                           <ci>v_max</ci>
                        </apply>
                        <ci>v</ci>
                     </apply>
                     <apply>
                        <leq/>
                        <ci>v</ci>
                        <cn cellml:units="micrometre_per_second">0</cn>
                     </apply>
                  </apply>
               </piece>
               <piece>
                  <apply>
                     <divide/>
                     <ci>P_star</ci>
                     <apply>
                        <plus/>
                        <apply>
                           <divide/>
                           <apply>
                              <times/>
                              <apply>
                                 <plus/>
                                 <apply>
                                    <times/>
                                    <cn cellml:units="dimensionless">0.4</cn>
                                    <ci>a</ci>
                                 </apply>
                                 <cn cellml:units="dimensionless">1</cn>
                              </apply>
                              <ci>v</ci>
                           </apply>
                           <apply>
                              <times/>
                              <ci>a</ci>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                        <cn cellml:units="dimensionless">1</cn>
                     </apply>
                  </apply>
                  <apply>
                     <and/>
                     <apply>
                        <lt/>
                        <cn cellml:units="micrometre_per_second">0</cn>
                        <ci>v</ci>
                     </apply>
                     <apply>
                        <leq/>
                        <ci>v</ci>
                        <ci>v_1</ci>
                     </apply>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <divide/>
                     <apply>
                        <times/>
                        <ci>P_star</ci>
                        <apply>
                           <exp/>
                           <apply>
                              <times/>
                              <apply>
                                 <minus/>
                                 <ci>alpha_G</ci>
                              </apply>
                              <apply>
                                 <power/>
                                 <apply>
                                    <divide/>
                                    <apply>
                                       <minus/>
                                       <ci>v</ci>
                                       <ci>v_1</ci>
                                    </apply>
                                    <ci>v_max</ci>
                                 </apply>
                                 <ci>alpha_P</ci>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <divide/>
                           <apply>
                              <times/>
                              <apply>
                                 <plus/>
                                 <apply>
                                    <times/>
                                    <cn cellml:units="dimensionless">0.4</cn>
                                    <ci>a</ci>
                                 </apply>
                                 <cn cellml:units="dimensionless">1</cn>
                              </apply>
                              <ci>v</ci>
                           </apply>
                           <apply>
                              <times/>
                              <ci>a</ci>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                        <cn cellml:units="dimensionless">1</cn>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>case_1</ci>
            <apply>
               <divide/>
               <apply>
                  <times/>
                  <ci>a</ci>
                  <apply>
                     <plus/>
                     <cn cellml:units="dimensionless">0.4</cn>
                     <apply>
                        <times/>
                        <cn cellml:units="dimensionless">0.4</cn>
                        <ci>a</ci>
                     </apply>
                  </apply>
               </apply>
               <apply>
                  <times/>
                  <ci>v_max</ci>
                  <apply>
                     <power/>
                     <apply>
                        <times/>
                        <apply>
                           <plus/>
                           <ci>a</ci>
                           <cn cellml:units="dimensionless">1</cn>
                        </apply>
                        <cn cellml:units="dimensionless">0.4</cn>
                     </apply>
                     <cn cellml:units="dimensionless">2</cn>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>case_2</ci>
            <apply>
               <divide/>
               <apply>
                  <times/>
                  <ci>a</ci>
                  <cn cellml:units="dimensionless">1</cn>
                  <apply>
                     <plus/>
                     <cn cellml:units="dimensionless">1</cn>
                     <apply>
                        <times/>
                        <cn cellml:units="dimensionless">0.4</cn>
                        <ci>a</ci>
                     </apply>
                     <apply>
                        <divide/>
                        <apply>
                           <times/>
                           <cn cellml:units="dimensionless">1.2</cn>
                           <ci>v</ci>
                        </apply>
                        <ci>v_max</ci>
                     </apply>
                     <apply>
                        <times/>
                        <cn cellml:units="dimensionless">0.6</cn>
                        <apply>
                           <power/>
                           <apply>
                              <divide/>
                              <ci>v</ci>
                              <ci>v_max</ci>
                           </apply>
                           <cn cellml:units="dimensionless">2</cn>
                        </apply>
                     </apply>
                  </apply>
               </apply>
               <apply>
                  <times/>
                  <ci>v_max</ci>
                  <apply>
                     <power/>
                     <apply>
                        <times/>
                        <apply>
                           <minus/>
                           <ci>a</ci>
                           <apply>
                              <divide/>
                              <ci>v</ci>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                        <apply>
                           <plus/>
                           <cn cellml:units="dimensionless">1</cn>
                           <apply>
                              <divide/>
                              <apply>
                                 <times/>
                                 <cn cellml:units="dimensionless">0.6</cn>
                                 <ci>v</ci>
                              </apply>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                     </apply>
                     <cn cellml:units="dimensionless">2</cn>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>case_3</ci>
            <apply>
               <divide/>
               <apply>
                  <plus/>
                  <apply>
                     <times/>
                     <cn cellml:units="dimensionless">0.4</cn>
                     <ci>a</ci>
                  </apply>
                  <cn cellml:units="dimensionless">1</cn>
               </apply>
               <apply>
                  <times/>
                  <ci>a</ci>
                  <ci>v_max</ci>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>case_4</ci>
            <apply>
               <times/>
               <apply>
                  <divide/>
                  <cn cellml:units="dimensionless">1</cn>
                  <ci>v_max</ci>
               </apply>
               <apply>
                  <exp/>
                  <apply>
                     <times/>
                     <apply>
                        <minus/>
                        <ci>alpha_G</ci>
                     </apply>
                     <apply>
                        <power/>
                        <apply>
                           <minus/>
                           <apply>
                              <divide/>
                              <ci>v</ci>
                              <ci>v_max</ci>
                           </apply>
                           <apply>
                              <divide/>
                              <ci>v_1</ci>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                        <ci>alpha_P</ci>
                     </apply>
                  </apply>
               </apply>
               <apply>
                  <plus/>
                  <apply>
                     <divide/>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <cn cellml:units="dimensionless">0.4</cn>
                           <ci>a</ci>
                        </apply>
                        <cn cellml:units="dimensionless">1</cn>
                     </apply>
                     <ci>a</ci>
                  </apply>
                  <apply>
                     <times/>
                     <ci>alpha_G</ci>
                     <ci>alpha_P</ci>
                     <apply>
                        <plus/>
                        <cn cellml:units="dimensionless">1</cn>
                        <apply>
                           <divide/>
                           <apply>
                              <times/>
                              <apply>
                                 <plus/>
                                 <apply>
                                    <times/>
                                    <cn cellml:units="dimensionless">0.4</cn>
                                    <ci>a</ci>
                                 </apply>
                                 <cn cellml:units="dimensionless">1</cn>
                              </apply>
                              <ci>v</ci>
                           </apply>
                           <apply>
                              <times/>
                              <ci>a</ci>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <power/>
                        <apply>
                           <minus/>
                           <apply>
                              <divide/>
                              <ci>v</ci>
                              <ci>v_max</ci>
                           </apply>
                           <apply>
                              <divide/>
                              <ci>v_1</ci>
                              <ci>v_max</ci>
                           </apply>
                        </apply>
                        <apply>
                           <minus/>
                           <ci>alpha_P</ci>
                           <cn cellml:units="dimensionless">1</cn>
                        </apply>
                     </apply>
                  </apply>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>p_v</ci>
            <apply>
               <divide/>
               <ci>P_star</ci>
               <ci>G_star</ci>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>p_prime_v</ci>
            <piecewise>
               <piece>
                  <ci>case_1</ci>
                  <apply>
                     <leq/>
                     <ci>v</ci>
                     <apply>
                        <minus/>
                        <ci>v_max</ci>
                     </apply>
                  </apply>
               </piece>
               <piece>
                  <ci>case_2</ci>
                  <apply>
                     <and/>
                     <apply>
                        <lt/>
                        <apply>
                           <minus/>
                           <ci>v_max</ci>
                        </apply>
                        <ci>v</ci>
                     </apply>
                     <apply>
                        <leq/>
                        <ci>v</ci>
                        <cn cellml:units="micrometre_per_second">0</cn>
                     </apply>
                  </apply>
               </piece>
               <piece>
                  <ci>case_3</ci>
                  <apply>
                     <and/>
                     <apply>
                        <lt/>
                        <cn cellml:units="micrometre_per_second">0</cn>
                        <ci>v</ci>
                     </apply>
                     <apply>
                        <leq/>
                        <ci>v</ci>
                        <ci>v_1</ci>
                     </apply>
                  </apply>
               </piece>
               <otherwise>
                  <ci>case_4</ci>
               </otherwise>
            </piecewise>
         </apply>
      </math>
   </component>
   <component name="calcium_handling">
      <variable name="A" units="micromole" initial_value="0.7" public_interface="out"/>
      <variable name="dA_dt" units="micromole_per_second"/>
      <variable name="N_A" units="dimensionless"/>
      <variable name="pi_N_A" units="dimensionless"/>
      <variable name="B" units="micromole" initial_value="0" public_interface="out"/>
      <variable name="dB_dt" units="micromole_per_second"/>
      <variable name="Ca_C" units="micromole" initial_value="0" public_interface="out"/>
      <variable name="time" units="second" public_interface="in"/>
      <variable name="N" units="dimensionless" public_interface="in"/>
      <variable name="a_on" units="per_second_micromole" public_interface="in"/>
      <variable name="a_off" units="per_second" public_interface="in"/>
      <variable name="k_A" units="per_micromole" public_interface="in"/>
      <variable name="L_oz" units="dimensionless" public_interface="in"/>
      <variable name="A_tot" units="micromole" initial_value="70"/>
      <variable name="B_tot" units="micromole" initial_value="28"/>
      <variable name="b_on" units="per_second_micromole" initial_value="37.143"/>
      <variable name="b_off" units="per_second" initial_value="182"/>
      <variable name="a_c" units="per_second2" initial_value="5200"/>
      <variable name="r_Ca" units="per_second" initial_value="650"/>
      <variable name="q_Ca" units="per_micromole" initial_value="0.714"/>
      <variable name="t_d" units="second" initial_value="0.033"/>
      <variable name="Ca_m" units="micromole" initial_value="2.1"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <apply>
            <eq/>
            <ci>N_A</ci>
            <apply>
               <divide/>
               <apply>
                  <times/>
                  <ci>A_tot</ci>
                  <ci>N</ci>
               </apply>
               <apply>
                  <times/>
                  <ci>L_oz</ci>
                  <ci>A</ci>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <ci>pi_N_A</ci>
            <piecewise>
               <piece>
                  <cn cellml:units="dimensionless">1</cn>
                  <apply>
                     <geq/>
                     <ci>N_A</ci>
                     <cn cellml:units="dimensionless">1</cn>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <power/>
                     <cn cellml:units="dimensionless">0.02</cn>
                     <ci>N_A</ci>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <ci>dA_dt</ci>
            <apply>
               <minus/>
               <apply>
                  <times/>
                  <ci>a_on</ci>
                  <apply>
                     <minus/>
                     <ci>A_tot</ci>
                     <ci>A</ci>
                  </apply>
                  <ci>Ca_C</ci>
               </apply>
               <apply>
                  <times/>
                  <ci>a_off</ci>
                  <apply>
                     <exp/>
                     <apply>
                        <times/>
                        <apply>
                           <minus/>
                           <ci>k_A</ci>
                        </apply>
                        <ci>A</ci>
                     </apply>
                  </apply>
                  <ci>pi_N_A</ci>
                  <ci>A</ci>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>A</ci>
            </apply>
            <ci>dA_dt</ci>
         </apply>
         <apply>
            <eq/>
            <ci>dB_dt</ci>
            <apply>
               <minus/>
               <apply>
                  <times/>
                  <ci>b_on</ci>
                  <apply>
                     <minus/>
                     <ci>B_tot</ci>
                     <ci>B</ci>
                  </apply>
                  <ci>Ca_C</ci>
               </apply>
               <apply>
                  <times/>
                  <ci>b_off</ci>
                  <ci>B</ci>
               </apply>
            </apply>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>B</ci>
            </apply>
            <ci>dB_dt</ci>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>Ca_C</ci>
            </apply>
            <piecewise>
               <piece>
                  <apply>
                     <times/>
                     <cn cellml:units="dimensionless">4</cn>
                     <ci>a_c</ci>
                     <ci>Ca_m</ci>
                     <ci>time</ci>
                     <apply>
                        <minus/>
                        <cn cellml:units="dimensionless">1</cn>
                        <apply>
                           <exp/>
                           <apply>
                              <times/>
                              <apply>
                                 <minus/>
                                 <ci>a_c</ci>
                              </apply>
                              <apply>
                                 <power/>
                                 <ci>time</ci>
                                 <cn cellml:units="dimensionless">2</cn>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <exp/>
                        <apply>
                           <times/>
                           <apply>
                              <minus/>
                              <ci>a_c</ci>
                           </apply>
                           <apply>
                              <power/>
                              <ci>time</ci>
                              <cn cellml:units="dimensionless">2</cn>
                           </apply>
                        </apply>
                     </apply>
                  </apply>
                  <apply>
                     <lt/>
                     <ci>time</ci>
                     <ci>t_d</ci>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <minus/>
                     <apply>
                        <minus/>
                        <apply>
                           <minus/>
                           <ci>dA_dt</ci>
                        </apply>
                        <ci>dB_dt</ci>
                     </apply>
                     <apply>
                        <times/>
                        <ci>r_Ca</ci>
                        <apply>
                           <exp/>
                           <apply>
                              <times/>
                              <apply>
                                 <minus/>
                                 <ci>q_Ca</ci>
                              </apply>
                              <ci>Ca_C</ci>
                           </apply>
                        </apply>
                        <ci>Ca_C</ci>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
      </math>
   </component>
   <connection>
      <map_components component_1="environment" component_2="isotonic"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="parameters" component_2="isotonic"/>
      <map_variables variable_1="isotonic" variable_2="isotonic"/>
   </connection>
   <connection>
      <map_components component_1="force" component_2="isotonic"/>
      <map_variables variable_1="F_muscle" variable_2="F_muscle"/>
   </connection>
   <connection>
      <map_components component_1="length" component_2="isotonic"/>
      <map_variables variable_1="isotonic_mode" variable_2="isotonic_mode"/>
      <map_variables variable_1="l" variable_2="l"/>
   </connection>
   <connection>
      <map_components component_1="PE_velocity" component_2="isotonic"/>
      <map_variables variable_1="isotonic_mode" variable_2="isotonic_mode"/>
   </connection>
   <connection>
      <map_components component_1="CE_velocity" component_2="isotonic"/>
      <map_variables variable_1="isotonic_mode" variable_2="isotonic_mode"/>
   </connection>
   <connection>
      <map_components component_1="environment" component_2="crossbridge_kinetics"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="environment" component_2="length"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="environment" component_2="CE_velocity"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="environment" component_2="PE_velocity"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="environment" component_2="calcium_handling"/>
      <map_variables variable_1="time" variable_2="time"/>
   </connection>
   <connection>
      <map_components component_1="parameters" component_2="parameters_izakov_et_al_1991"/>
      <map_variables variable_1="v_max" variable_2="v_max"/>
   </connection>
   <connection>
      <map_components component_1="force" component_2="parameters"/>
      <map_variables variable_1="alpha_1" variable_2="alpha_1"/>
      <map_variables variable_1="beta_1" variable_2="beta_1"/>
      <map_variables variable_1="alpha_2" variable_2="alpha_2"/>
      <map_variables variable_1="beta_2" variable_2="beta_2"/>
      <map_variables variable_1="alpha_3" variable_2="alpha_3"/>
      <map_variables variable_1="beta_3" variable_2="beta_3"/>
      <map_variables variable_1="lambda" variable_2="lambda"/>
   </connection>
   <connection>
      <map_components component_1="force" component_2="crossbridge_kinetics"/>
      <map_variables variable_1="N" variable_2="N"/>
   </connection>
   <connection>
      <map_components component_1="force" component_2="length"/>
      <map_variables variable_1="l_1" variable_2="l_1"/>
      <map_variables variable_1="l_2" variable_2="l_2"/>
      <map_variables variable_1="l_3" variable_2="l_3"/>
   </connection>
   <connection>
      <map_components component_1="force" component_2="CE_velocity"/>
      <map_variables variable_1="v" variable_2="v"/>
      <map_variables variable_1="k_P_vis" variable_2="k_P_vis"/>
   </connection>
   <connection>
      <map_components component_1="force" component_2="PE_velocity"/>
      <map_variables variable_1="w" variable_2="w"/>
      <map_variables variable_1="k_S_vis" variable_2="k_S_vis"/>
   </connection>
   <connection>
      <map_components component_1="force" component_2="average_crossbridge_force"/>
      <map_variables variable_1="p_v" variable_2="p_v"/>
   </connection>
   <connection>
      <map_components component_1="crossbridge_kinetics" component_2="parameters"/>
      <map_variables variable_1="A_half" variable_2="A_half"/>
      <map_variables variable_1="mu" variable_2="mu"/>
      <map_variables variable_1="chi" variable_2="chi"/>
      <map_variables variable_1="chi_0" variable_2="chi_0"/>
      <map_variables variable_1="m_0" variable_2="m_0"/>
   </connection>
   <connection>
      <map_components component_1="crossbridge_kinetics" component_2="calcium_handling"/>
      <map_variables variable_1="A" variable_2="A"/>
      <map_variables variable_1="N" variable_2="N"/>
      <map_variables variable_1="L_oz" variable_2="L_oz"/>
   </connection>
   <connection>
      <map_components component_1="crossbridge_kinetics" component_2="average_crossbridge_force"/>
      <map_variables variable_1="G_star" variable_2="G_star"/>
      <map_variables variable_1="P_star" variable_2="P_star"/>
   </connection>
   <connection>
      <map_components component_1="crossbridge_kinetics" component_2="length"/>
      <map_variables variable_1="l_1" variable_2="l_1"/>
   </connection>
   <connection>
      <map_components component_1="crossbridge_kinetics" component_2="CE_velocity"/>
      <map_variables variable_1="K_chi" variable_2="K_chi"/>
      <map_variables variable_1="v" variable_2="v"/>
      <map_variables variable_1="N" variable_2="N"/>
   </connection>
   <connection>
      <map_components component_1="crossbridge_kinetics" component_2="parameters_izakov_et_al_1991"/>
      <map_variables variable_1="S_0" variable_2="S_0"/>
      <map_variables variable_1="q_v" variable_2="q_v"/>
      <map_variables variable_1="v_star" variable_2="v_star"/>
      <map_variables variable_1="q_4" variable_2="q_4"/>
   </connection>
   <connection>
      <map_components component_1="length" component_2="CE_velocity"/>
      <map_variables variable_1="v" variable_2="v"/>
      <map_variables variable_1="phi_chi_2" variable_2="phi_chi_2"/>
      <map_variables variable_1="dl_1_dt" variable_2="dl_1_dt"/>
      <map_variables variable_1="l_1" variable_2="l_1"/>
      <map_variables variable_1="l_2" variable_2="l_2"/>
      <map_variables variable_1="l_3" variable_2="l_3"/>
   </connection>
   <connection>
      <map_components component_1="length" component_2="PE_velocity"/>
      <map_variables variable_1="w" variable_2="w"/>
      <map_variables variable_1="k_S_vis" variable_2="k_S_vis"/>
      <map_variables variable_1="dl_1_dt" variable_2="dl_1_dt"/>
      <map_variables variable_1="l_1" variable_2="l_1"/>
      <map_variables variable_1="dl_2_dt" variable_2="dl_2_dt"/>
      <map_variables variable_1="l_2" variable_2="l_2"/>
      <map_variables variable_1="l_3" variable_2="l_3"/>
   </connection>
   <connection>
      <map_components component_1="CE_velocity" component_2="parameters"/>
      <map_variables variable_1="alpha_1" variable_2="alpha_1"/>
      <map_variables variable_1="beta_1" variable_2="beta_1"/>
      <map_variables variable_1="alpha_2" variable_2="alpha_2"/>
      <map_variables variable_1="beta_2" variable_2="beta_2"/>
      <map_variables variable_1="alpha_3" variable_2="alpha_3"/>
      <map_variables variable_1="beta_3" variable_2="beta_3"/>
      <map_variables variable_1="lambda" variable_2="lambda"/>
   </connection>
   <connection>
      <map_components component_1="CE_velocity" component_2="parameters_izakov_et_al_1991"/>
      <map_variables variable_1="v" variable_2="v"/>
   </connection>
   <connection>
      <map_components component_1="CE_velocity" component_2="PE_velocity"/>
      <map_variables variable_1="v" variable_2="v"/>
      <map_variables variable_1="w" variable_2="w"/>
      <map_variables variable_1="k_S_vis" variable_2="k_S_vis"/>
      <map_variables variable_1="phi_chi" variable_2="phi_chi"/>
   </connection>
   <connection>
      <map_components component_1="PE_velocity" component_2="parameters"/>
      <map_variables variable_1="alpha_1" variable_2="alpha_1"/>
      <map_variables variable_1="beta_1" variable_2="beta_1"/>
      <map_variables variable_1="alpha_2" variable_2="alpha_2"/>
      <map_variables variable_1="beta_2" variable_2="beta_2"/>
      <map_variables variable_1="alpha_3" variable_2="alpha_3"/>
      <map_variables variable_1="beta_3" variable_2="beta_3"/>
      <map_variables variable_1="lambda" variable_2="lambda"/>
   </connection>
   <connection>
      <map_components component_1="average_crossbridge_force" component_2="parameters"/>
      <map_variables variable_1="v_max" variable_2="v_max"/>
      <map_variables variable_1="a" variable_2="a"/>
      <map_variables variable_1="d_h" variable_2="d_h"/>
      <map_variables variable_1="alpha_P" variable_2="alpha_P"/>
   </connection>
   <connection>
      <map_components component_1="average_crossbridge_force" component_2="parameters_izakov_et_al_1991"/>
      <map_variables variable_1="v_1" variable_2="v_1"/>
      <map_variables variable_1="alpha_G" variable_2="alpha_G"/>
   </connection>
   <connection>
      <map_components component_1="average_crossbridge_force" component_2="CE_velocity"/>
      <map_variables variable_1="v" variable_2="v"/>
      <map_variables variable_1="phi_chi" variable_2="phi_chi"/>
      <map_variables variable_1="p_v" variable_2="p_v"/>
      <map_variables variable_1="p_prime_v" variable_2="p_prime_v"/>
   </connection>
   <connection>
      <map_components component_1="calcium_handling" component_2="parameters_izakov_et_al_1991"/>
      <map_variables variable_1="a_on" variable_2="a_on"/>
      <map_variables variable_1="a_off" variable_2="a_off"/>
      <map_variables variable_1="k_A" variable_2="k_A"/>
   </connection>
</model>