35q9235r3537n2549j1092c5092d2535b3235b3535b50 applications bifurcation biology biologyandothernaturalsciences calculusofvariationsandoptimalcontrol;optimization cellularandmedicaltopics dynamicalsystemsandergodictheory dynamicalsystemsinbiology equationsofmathematicalphysicsandotherareasofapplication existencetheories freeboundaryproblems freeproblemsintwoormoreindependentvariables geneticsandpopulationdynamics mathematicalmodels medicalapplications(general) miscellaneoustopics partialdifferentialequations pdesinconnectionwithbiologyandothernaturalsciences physiological populationdynamics(general) qualitativepropertiesofsolutions stability