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1989.
Oscillations and global attractivity in respiratory dynamics
Let x(e:t) denote the arterial concentration of CO2. Mackey and Glass (1977) have proposed that x(t) is governed by the autonomous delay differential equation (*) where γ, β, z.Θ are positive parameters, τ is a non-negative delay and Vm denotes the maximum ‘ventilation’ rate of CO2. We obtain sufficient and also necessary and sufficient conditions for all positive solutions of (*) to oscillate about the positive equilibrium x * of (*). We also obtain sufficient conditions for x * to be a global attractor.