AspectSubTreeNode visualization = electrical.getSubTree(AspectTreeType.VISUALIZATION_TREE);
SphereNode sphere = new SphereNode("purkinje");
visualization.addChild(sphere);
runtime.addChild(hhcell);
runtime.addChild(purkinje);
hhcell.getAspects().add(electrical);
purkinje.getAspects().add(electrical2);
electrical.setParent(hhcell);
electrical2.setParent(purkinje);