In this paper, the following third-order nonlinear delay differential equation with periodic coefficients x′′′(t) + p(t)x′′(t) + q(t)x′(t) + r(t)x(t) = f (t, x (t) , x(t− τ(t))) + d dt g (t, x (t− τ (t))) , is considered. By employing Green’s function, Krasnoselskii’s fixed point theorem and the contraction mapping principle, we state and prove the existence and uniqueness of periodic solutions...

Let T be a periodic time scale. We use Krasnoselskii’s fixed point theorem to show that the neutral functional differential equation with impulses x(t) = −A(t)x(t) + g(t, x(t− h(t))) + f(t, x(t), x(t− h(t))), t 6= tj , t ∈ T, x(t+j ) = x(t − j ) + Ij(x(tj)), j ∈ Z + has a periodic solution. Under a slightly more stringent conditions we show that the periodic solution is unique using the contrac...

The second order nonlinear delay differential equation with periodic coefficients x ′′(t)+ p(t)x ′(t)+ q(t)x(t) = r(t)x ′(t − τ(t))+ f (t, x(t), x(t − τ(t))), t ∈ R is considered in this work. By using Krasnoselskii’s fixed point theorem and the contraction mapping principle, we establish some criteria for the existence and uniqueness of periodic solutions to the delay differential equation. c ...

By using a fixed point theorem of strict-set-contraction, some criteria are established for the existence of positive periodic solutions of the following impulsive functional differential equations with a parameter <: ẋ(t) = −a(t)f(t, x(t))x(t) + λg(t, xt, x(t− τ(t, x(t))), t ∈ R, and t 6= tk, x(t+k )− x(t − k ) = Ik(tk, x(tk − τ(tk, x(tk)))), k ∈ Z.

RATIONALE Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) are increasingly being used for modeling heart disease and are under development for regeneration of the injured heart. However, incomplete structural and functional maturation of hiPSC-CM, including lack of T-tubules, immature excitation-contraction coupling, and inefficient Ca-induced Ca release remain major limit...

Transverse (T)-tubules make-up a specialized network of tubulated muscle cell membranes involved in excitation-contraction coupling for power of contraction. Little is known about how T-tubules maintain highly organized structures and contacts throughout the contractile system despite the ongoing muscle remodeling that occurs with muscle atrophy, damage and aging. We uncovered an essential role...

In this article we study the existence of periodic solutions of the second order nonlinear neutral differential equation with functional delay d dt x (t) + p (t) d dt x (t) + q (t) x (t) = d dt g (t, x (t− τ (t))) + f ` t, x (t) , x (t− τ (t)) ́ . The main tool employed here is the Burton-Krasnoselskii’s hybrid fixed point theorem dealing with a sum of two mappings, one is a large contraction an...

1. A multimodel, multisegmental interneurone (Röhde's fibre, RF) and previously identified mechanoreceptors (T-cells) are shown to respond to nearfield disturbances. Both the T-cells and RF can fire for hundreds of milliseconds following a brief stimulus, and both have subthreshold excitatory synapses onto motor neurones that cause longitudinal contraction of the body wall, an avoidance respons...

Mechanical activation of the normal left ventricle (LV) is not simultaneous; however, the potential consequences of the ejection function of the ventricle are not entirely known. We studied contraction of the LV free wall to determine whether it reveals a contraction wave in the axial direction during ejection. Seven guinea pig hearts in situ were studied via thoracotomy. In each heart, the ven...