Kerchoffs2003ContractionModel Class Reference

#include <Kerchoffs2003ContractionModel.hpp>

Inherits AbstractOdeBasedContractionModel.

Collaboration diagram for Kerchoffs2003ContractionModel:

Public Member Functions
	Kerchoffs2003ContractionModel ()
void	EvaluateYDerivatives (double time, const std::vector< double > &rY, std::vector< double > &rDY)
void	SetInputParameters (ContractionModelInputParameters &rInputParameters)
void	SetStretchAndStretchRate (double stretch, double stretchRate)
double	GetActiveTension ()
bool	IsStretchDependent ()
bool	IsStretchRateDependent ()
double	GetNextActiveTension ()
Private Member Functions
double	GetActiveTension (double lengthOfContractileElement)
Private Attributes
double	mSarcomereLength
double	mActivationTime
bool	mIsActivated
bool	mElectricallyUnactivated
Static Private Attributes
static const double	a6 = 2.0
static const double	a7 = 1.5
static const double	T0 = 180
static const double	Ea = 20
static const double	v0 = 0.0075
static const double	ls0 = 1.9
static const double	tr = 75
static const double	td = 75
static const double	b = 150
static const double	ld = -0.4
static const double	mActivationVoltage = 0
static const double	mDeactivationVoltage = -70
Friends
class	TestContractionModels

Detailed Description

Implementation of the ODE-based, stretch-dependent, stretch-rate-INdependent, contraction model detailed in the appendix of Kerchoffs 2003 "Intra- and interventricular asynchrony of electromechanics in the ventricularly paced heart".

Definition at line 41 of file Kerchoffs2003ContractionModel.hpp.

Constructor & Destructor Documentation

Kerchoffs2003ContractionModel::Kerchoffs2003ContractionModel ( )

Constructor

Definition at line 46 of file Kerchoffs2003ContractionModel.cpp.

References Ea, ls0, mActivationTime, mElectricallyUnactivated, mIsActivated, AbstractUntemplatedParameterisedSystem::mpSystemInfo, mSarcomereLength, AbstractParameterisedSystem< std::vector< double > >::mStateVariables, and AbstractOdeBasedContractionModel::mTime.

Member Function Documentation

void Kerchoffs2003ContractionModel::EvaluateYDerivatives	(	double	time,
		const std::vector< double > &	rY,
		std::vector< double > &	rDY
	)			`[virtual]`

The derivative function of the one state variable: "lc" in reference, the length of the contractile element

Parameters:

	time	time
	rY	1D vector containing lc
	rDY	1D vector in which dlc/dt is set

Implements AbstractOdeSystem.

Definition at line 62 of file Kerchoffs2003ContractionModel.cpp.

References Ea, mSarcomereLength, and v0.

double Kerchoffs2003ContractionModel::GetActiveTension ( ) [virtual]

Get the active tension (note: actually a stress), ie kPa

Implements AbstractContractionModel.

Definition at line 130 of file Kerchoffs2003ContractionModel.cpp.

References AbstractParameterisedSystem< std::vector< double > >::mStateVariables.

Referenced by GetNextActiveTension().

double Kerchoffs2003ContractionModel::GetActiveTension ( double lengthOfContractileElement ) [private]

Get the active tension as a function of length of contractile element. This is private. The public GetActiveTension() calls this using the value of lc in the state variable

Parameters:

lengthOfContractileElement

length of contractile element (the state variable in this model).

Definition at line 98 of file Kerchoffs2003ContractionModel.cpp.

References a6, a7, b, Ea, ld, ls0, mActivationTime, mElectricallyUnactivated, mIsActivated, mSarcomereLength, AbstractOdeBasedContractionModel::mTime, T0, td, and tr.

double Kerchoffs2003ContractionModel::GetNextActiveTension ( ) [virtual]

Get the active tension corresponding to the temporary stored state variables produced by calling RunDoNotUpdate (and before calling UpdateStateVariables())

Implements AbstractContractionModel.

Definition at line 135 of file Kerchoffs2003ContractionModel.cpp.

References GetActiveTension(), and AbstractOdeBasedContractionModel::mTemporaryStateVariables.

bool Kerchoffs2003ContractionModel::IsStretchDependent ( ) [inline, virtual]

This model is stretch-dependent

Implements AbstractContractionModel.

Definition at line 117 of file Kerchoffs2003ContractionModel.hpp.

bool Kerchoffs2003ContractionModel::IsStretchRateDependent ( ) [inline, virtual]

This model is stretch-rate-independent

Implements AbstractContractionModel.

Definition at line 125 of file Kerchoffs2003ContractionModel.hpp.

void Kerchoffs2003ContractionModel::SetInputParameters ( ContractionModelInputParameters & rInputParameters ) [virtual]

Set the input parameters. The calcium concentration is not used. If the voltage is such that activation has occured (gone above mActivationVoltage), the state is set to active and the time saved as the activation time.

Parameters:

rInputParameters

reference to the input parameters

Implements AbstractContractionModel.

Definition at line 71 of file Kerchoffs2003ContractionModel.cpp.

References DOUBLE_UNSET, mActivationTime, mActivationVoltage, mDeactivationVoltage, mElectricallyUnactivated, mIsActivated, AbstractOdeBasedContractionModel::mTime, and ContractionModelInputParameters_::voltage.

void Kerchoffs2003ContractionModel::SetStretchAndStretchRate	(	double	stretch,
		double	stretchRate
	)			`[virtual]`

Take the stretch and compute the sarcomere length (stretch rate is not used).

Parameters:

	stretch	stretch
	stretchRate	stretch rate

Implements AbstractContractionModel.

Definition at line 92 of file Kerchoffs2003ContractionModel.cpp.

References ls0, and mSarcomereLength.

Member Data Documentation

const double Kerchoffs2003ContractionModel::a6 = 2.0 [static, private]

See reference. 2.0 um^{-1}

Definition at line 46 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension().

const double Kerchoffs2003ContractionModel::a7 = 1.5 [static, private]

See reference. 1.5 um

Definition at line 47 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension().

const double Kerchoffs2003ContractionModel::b = 150 [static, private]

See reference. 150 ms/um

Definition at line 54 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension().

const double Kerchoffs2003ContractionModel::Ea = 20 [static, private]

See reference. 20 um^{-1}

Definition at line 49 of file Kerchoffs2003ContractionModel.hpp.

Referenced by EvaluateYDerivatives(), GetActiveTension(), and Kerchoffs2003ContractionModel().

const double Kerchoffs2003ContractionModel::ld = -0.4 [static, private]

See reference. -0.4 um

Definition at line 55 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension().

const double Kerchoffs2003ContractionModel::ls0 = 1.9 [static, private]

See reference. 1.9 um

Definition at line 51 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension(), Kerchoffs2003ContractionModel(), and SetStretchAndStretchRate().

double Kerchoffs2003ContractionModel::mActivationTime [private]

Time (ms) of electrical activation (= time the voltage at this cell reached mActivationVoltage)

Definition at line 65 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension(), Kerchoffs2003ContractionModel(), and SetInputParameters().

const double Kerchoffs2003ContractionModel::mActivationVoltage = 0 [static, private]

Voltage threshold above which the cell is activated (mV) - note hysteresis

Definition at line 58 of file Kerchoffs2003ContractionModel.hpp.

Referenced by SetInputParameters().

const double Kerchoffs2003ContractionModel::mDeactivationVoltage = -70 [static, private]

Voltage threshold below which the cell is deactivated (mV)

Definition at line 60 of file Kerchoffs2003ContractionModel.hpp.

Referenced by SetInputParameters().

bool Kerchoffs2003ContractionModel::mElectricallyUnactivated [private]

Whether the cell is electrically unactivated yet (whether the voltage has gone below mDeactivationVoltage

Definition at line 72 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension(), Kerchoffs2003ContractionModel(), and SetInputParameters().

bool Kerchoffs2003ContractionModel::mIsActivated [private]

Whether the cell is activated - whether the voltage has gone above mActivationTime and not gone below without going below mDeactivationVoltage, and that the cell has stopped producing force.

Definition at line 69 of file Kerchoffs2003ContractionModel.hpp.

Referenced by GetActiveTension(), Kerchoffs2003ContractionModel(), and SetInputParameters().

double Kerchoffs2003ContractionModel::mSarcomereLength [private]

Length of the sarcomere in um. Variable "ls" in reference. Fibre-stretch is ls/ls0.

Definition at line 63 of file Kerchoffs2003ContractionModel.hpp.

Referenced by EvaluateYDerivatives(), GetActiveTension(), Kerchoffs2003ContractionModel(), and SetStretchAndStretchRate().