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Samuel Bowong

Publications and source records attributed to Samuel Bowong.

5 recordsLinked to original sources
arXiv2025

Traveling chimeras and collective coordination in beta-cell networks

Pancreatic $\beta$-cells play a central role in maintaining glucose homeostasis through the pulsatile secretion of insulin. This essential function relies not only on intracellular regulatory mechanisms but also on coordinated interactions among $\beta$-cells within the islets of Langerhans. Disruptions in this intercellular coordination are increasingly implicated in metabolic disorders such as type~I and type~II diabetes. In this work, we employ a computational framework to investigate the collective dynamics of a network of coupled $\beta$-cells interacting through a nonlocally coupled ring topology that incorporates both electrical and metabolic coupling pathways. This topology captures short- and long-range interactions known to shape islet communication. Numerical simulations reveal a variety of emergent behaviors, including synchronization, traveling waves, and traveling chimera states, in which coherent and incoherent domains coexist and propagate across the network. These findings provide new insight into the mechanisms governing coordinated $\beta$-cell activity and the regulation of pulsatile insulin secretion. By clarifying how coupling structure and intercellular communication shape islet-wide dynamics, this work contributes to a deeper understanding of the dysfunctions underlying diabetes.

physics.bio-ph↗
arXiv2025

Global stability analysis of an age-structured model assessing the impact of Radopholus similis on banana-plantain production

In this paper, we develop and analyse a mathematical model to investigate the interactions between banana and plantain plants and the nematode \textit{Radopholus similis}, a pest species occurring in banana plantations worldwide, with particularly high prevalence in Central Africa. The model incorporates root infection and mortality rates as functions of root age, providing a more realistic representation of the infection dynamics. We prove that the model is well-defined by establishing the existence and uniqueness of a mild solution using the theory of semi-groups for nonlinear evolutionary systems. We further show that the solution is positive and bounded. Under additional assumptions on the regularity of the parameters and the data, we prove that the mild solution is indeed a classical solution. We then study the asymptotic behaviour of the solution by deriving a threshold parameter \(\mathcal{N}\), which determines the stability of the disease-free equilibrium. Finally, we perform a numerical analysis of the proposed model using the semi-implicit Euler method. The biological consistency of the numerical solutions is established, and simulations are carried out to illustrate the theoretical results and estimate yield losses caused by nematodes. We conclude the numerical analysis by implementing an impulsive control strategy, which confirms that the use of nematicides - whether chemical or biological - helps to mitigate the devastating effects of nematodes and enhances crop yield.

math.AP↗
arXiv2013

Finite-time synchronization of tunnel diode based chaotic oscillators

This paper addresses the problem of finite-time synchronization of tunnel diode based chaotic oscillators. After a brief investigation of its chaotic dynamics, we propose an active adaptive feedback coupling which accomplishes the synchronization of tunnel diode based chaotic systems with and without the presence of delay(s), basing ourselves on Lyapunov and on Krasovskii-Lyapunov stability theories. This feedback coupling could be applied to many other chaotic systems. A finite horizon can be arbitrarily established by ensuring that chaos synchronization is achieved at a pre-established time. An advantage of the proposed feedback coupling is that it is simple and easy to implement. Both mathematical investigations and numerical simulatio

nlin.CD↗
arXiv2011

Analysis of the spread of tuberculosis in heterogeneous complex metapopulations

his paper describes and analyzes the spatial spread of tuberculosis (TB) on complex metapopulation, that is, networks of populations connected by migratory flows whose configurations are described in terms of connectivity distribution of nodes (patches) and the conditional probabilities of connections among classes of nodes sharing the same degree. The migration and transmission processes occur simultaneously. For uncorrelated networks under the assumption of standard incidence transmission, we compute the disease-free equilibrium and the basic reproduction number, and show that the disease-free equilibrium is locally asymptotically stable. Moreover, for uncorrelated networks and under assumption of simple mass action transmission, we give a necessary and sufficient conditions for the instability of the disease-free equilibrium. The existence of endemic equilibria is also discussed. Finally, the prevalence of the TB infection across the metapopulation as a function of the path connectivity is studied using numerical simulations.

math.DS↗