Location: Katsnelson, Nikitina, Chemla, Solovyova, Coirault, Lecarpentier, Markhasin, 2004 @ 5725a8a06502 / katsnelson_nikitina_chemla_solovyova_coirault_lecarpentier_markhasin_2004.cellml

Author:
pmr2.import <nobody@models.cellml.org>
Date:
2008-07-25 04:22:31+12:00
Desc:
committing version01 of katsnelson_nikitina_chemla_solovyova_coirault_lecarpentier_markhasin_2004
Permanent Source URI:
https://models.cellml.org/workspace/katsnelson_nikitina_chemla_solovyova_coirault_lecarpentier_markhasin_2004/rawfile/5725a8a065022345930a3b20ada941f4179bb864/katsnelson_nikitina_chemla_solovyova_coirault_lecarpentier_markhasin_2004.cellml

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This CellML file was generated on 23/07/2008 at 2:08:01 at p.m. using:

COR (0.9.31.979)
Copyright 2002-2008 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/
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<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 runs in PCEnv, but does not recreate the published results. Units are consistent throughout.        
          </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>
					<ulink url="http://www.sciencedirect.com/science?_ob=ArticleURL&amp;_udi=B6WMD-4CVX3GD-2&amp;_user=140507&amp;_rdoc=1&amp;_fmt=&amp;_orig=search&amp;_sort=d&amp;view=c&amp;_acct=C000011498&amp;_version=1&amp;_urlVersion=0&amp;_userid=140507&amp;md5=60ef8c8017472b990eae05ba7278d92f">Influence of viscosity on myocardium mechanical activity: a mathematical model</ulink>, Leonid B. Katsnelson, Larissa V. Nikitina, Denis Chemla, Olga Solovyova, Catherine Coirault, Yves Lecarpentier and Vladimir S. Markhasin, 2004, <ulink url="http://www.elsevier.com/wps/find/journaldescription.cws_home/622904/description#description">
						<emphasis>Journal of Theoretical Biology</emphasis>
					</ulink>, 230, 385-485.  (<ulink url="http://www.sciencedirect.com/science?_ob=MImg&amp;_imagekey=B6WMD-4CVX3GD-2-25&amp;_cdi=6932&amp;_user=140507&amp;_orig=search&amp;_coverDate=10%2F07%2F2004&amp;_sk=997699996&amp;view=c&amp;wchp=dGLbVtz-zSkWb&amp;md5=41a73e3b6fa1a75ff45f99a41d8c2a5b&amp;ie=/sdarticle.pdf">PDF</ulink> versions of the article are available for Journal Members on the Elsevier website.)  <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>
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                           <ci>N</ci>
                           <ci>p_prime_v</ci>
                           <cn cellml:units="millisecond">1</cn>
                        </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>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>lambda</ci>
                           <ci>K_chi</ci>
                           <ci>p_v</ci>
                           <cn cellml:units="um_per_msec">1</cn>
                        </apply>
                        <apply>
                           <times/>
                           <ci>alpha_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>
                           <cn cellml:units="um_per_msec">1</cn>
                        </apply>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <times/>
                           <ci>lambda</ci>
                           <ci>N</ci>
                           <ci>p_prime_v</ci>
                           <cn cellml:units="millisecond">1</cn>
                        </apply>
                        <ci>k_P_vis</ci>
                     </apply>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
         <apply>
            <eq/>
            <apply>
               <diff/>
               <bvar>
                  <ci>time</ci>
               </bvar>
               <ci>v</ci>
            </apply>
            <ci>phi_chi</ci>
         </apply>
      </math>
   </component>
   <component name="PE_velocity">
      <variable units="um_per_msec" public_interface="out" name="w" initial_value="0"/>
      <variable units="mN" public_interface="out" name="k_S_vis"/>
      <variable units="millisecond" public_interface="in" name="time"/>
      <variable units="um_per_msec" public_interface="in" name="v"/>
      <variable units="um_per_msec2" public_interface="in" name="phi_chi"/>
      <variable units="um" public_interface="in" name="l_1"/>
      <variable units="um_per_msec" public_interface="in" name="dl_1_dt"/>
      <variable units="um" public_interface="in" name="l_2"/>
      <variable units="um_per_msec" public_interface="in" name="dl_2_dt"/>
      <variable units="um" public_interface="in" name="l_3"/>
      <variable units="per_um" public_interface="in" name="alpha_1"/>
      <variable units="mN" public_interface="in" name="beta_1"/>
      <variable units="per_um" public_interface="in" name="alpha_2"/>
      <variable units="mN" public_interface="in" name="beta_2"/>
      <variable units="per_um" public_interface="in" name="alpha_3"/>
      <variable units="mN" public_interface="in" name="beta_3"/>
      <variable units="mN" public_interface="in" name="lambda"/>
      <variable units="dimensionless" public_interface="in" name="isotonic_mode"/>
      <variable units="per_um" public_interface="in" name="alpha_S"/>
      <variable units="per_um" name="alpha_S_lengthening" initial_value="39"/>
      <variable units="mN" name="beta_S_lengthening" initial_value="80"/>
      <variable units="per_um" name="alpha_S_shortening" initial_value="46"/>
      <variable units="mN" name="beta_S_shortening" initial_value="60"/>
      <math xmlns="http://www.w3.org/1998/Math/MathML">
         <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>dl_2_dt</ci>
                     <ci>dl_1_dt</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>alpha_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>
                              <cn cellml:units="um_per_msec">1</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>
                           <cn cellml:units="um_per_msec">1</cn>
                        </apply>
                     </apply>
                     <ci>k_S_vis</ci>
                  </apply>
                  <apply>
                     <eq/>
                     <ci>isotonic_mode</ci>
                     <cn cellml:units="dimensionless">1</cn>
                  </apply>
               </piece>
               <otherwise>
                  <apply>
                     <divide/>
                     <apply>
                        <minus/>
                        <apply>
                           <minus/>
                           <apply>
                              <times/>
                              <ci>k_S_vis</ci>
                              <apply>
                                 <minus/>
                                 <ci>phi_chi</ci>
                                 <apply>
                                    <times/>
                                    <ci>alpha_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>
                              <cn cellml:units="um_per_msec">1</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>
                           <cn cellml:units="um_per_msec">1</cn>
                        </apply>
                     </apply>
                     <ci>k_S_vis</ci>
                  </apply>
               </otherwise>
            </piecewise>
         </apply>
      </math>
   </component>
   <component name="average_crossbridge_force">
      <variable units="dimensionless" public_interface="out" name="p_v"/>
      <variable units="per_millisecond" public_interface="out" name="p_prime_v"/>
      <variable units="dimensionless" public_interface="out" name="P_star"/>
      <variable units="dimensionless" public_interface="out" name="G_star"/>
      <variable units="dimensionless" name="gamma"/>
      <variable units="per_millisecond" name="case_1"/>
      <variable units="per_millisecond" name="case_2"/>
      <variable units="per_millisecond" name="case_3"/>
      <variable units="per_millisecond" name="case_4"/>
      <variable units="um_per_msec" public_interface="in" name="v"/>
      <variable units="um_per_msec2" public_interface="in" name="phi_chi"/>
      <variable units="um_per_msec" public_interface="in" name="v_1"/>
      <variable units="um_per_msec" public_interface="in" name="v_max"/>
      <variable units="dimensionless" public_interface="in" name="a"/>
      <variable units="dimensionless" public_interface="in" name="d_h"/>
      <variable units="dimensionless" public_interface="in" name="alpha_G"/>
      <variable units="dimensionless" public_interface="in" name="alpha_P"/>
      <variable units="dimensionless" public_interface="in" name="alpha_PG"/>
      <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</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="um_per_msec">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="um_per_msec">0</cn>
                     </apply>
                  </apply>
               </piece>
               <piece>
                  <apply>
                     <divide/>
                     <ci>P_star</ci>
                     <apply>
                        <plus/>
                        <apply>
                           <divide/>
                           <apply>
                              <times/>
                              <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>
                              <ci>v</ci>
                           </apply>
                           <ci>v_max</ci>
                        </apply>
                        <cn cellml:units="dimensionless">1</cn>
                     </apply>
                  </apply>
                  <apply>
                     <and/>
                     <apply>
                        <lt/>
                        <cn cellml:units="um_per_msec">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_PG</ci>
                              </apply>
                           </apply>
                        </apply>
                     </apply>
                     <apply>
                        <plus/>
                        <apply>
                           <divide/>
                           <apply>
                              <times/>
                              <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>
                              <ci>v</ci>
                           </apply>
                           <ci>v_max</ci>
                        </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="um_per_msec2">0.4</cn>
                     <apply>
                        <times/>
                        <cn cellml:units="um_per_msec2">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="um_per_msec2">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="um_per_msec2">0.4</cn>
                     <ci>a</ci>
                  </apply>
                  <cn cellml:units="um_per_msec2">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="um_per_msec2">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_PG</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>
               </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_PG</ci>
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    <vCard:Given>Catherine </vCard:Given>
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    <vCard:Given>Larissa</vCard:Given>
    <vCard:Family>Nikitina</vCard:Family>
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    <vCard:Given>Yves </vCard:Given>
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    <vCard:Given>Geoffrey</vCard:Given>
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    <vCard:Given>Vladimir </vCard:Given>
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    <vCard:Given>Olga </vCard:Given>
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