Sarangam Majumdar

Bacterial Communication And Relevance Of Quantum Theory

The recent findings confirm that bacteria communicate each other through chemical and electrical signals. Bacteria use chemical signaling molecules which are called as quorum sensing molecules(QSMs) or autoinducers. Moreover, the ion channels in bacteria conduct a long-range electrical signaling within biofilm communities through propagated waves of potassium ions and biofilms attracts other bacterial species too. Both communication process are used by bacteria to make their own survival strategies. In this article, we model this bacterial communication mechanism by complex Ginzburg- Landau equation and discuss the formation of patterns depending on kinematic viscosity associated with internal noise. Again, the potassium wave propagation is described by the non-linear Schrödinger equation in a dissipative environment. By adding perturbation to non-linear Schrödinger equation one arrives at Complex Ginzburg-Landau equation. In this paper we emphasize that at the cellular level(bacteria) we use Complex Ginzburg - Landau equation as a perturbed Nonlinear Schrödinger equation to understand the bacterial communication as well as pattern formation in Biofilms for certain range of kinematic viscosity which can be tested in laboratory experiment. Here, the perturbation is due to the existence of non thermal fluctuations associated to the finite size of the bacteria. It sheds new light on the relevance of quantum formalism in understanding the cell to cell communication.

Convection - Diffusion model of talking bacteria

Quorum sensing is cell to cell communication process through chemical signals formally known as autoinducers. When the concentration of quorum sensing molecules reached threshold concentration bacteria are in active state or quorum state. In this article, we propose a mathematical model of quorum sensing systems and study this biological system numerically. Moreover, we compare the different numerical scheme with the batch culture of P.aeruginosa. We observed a negative diffusion coefficient which plays an important role in the quorum sensing mechanism.

The role of coherence in bacterial communication

Bacteria within biofilms can coordinate their behavior through distinct from of communication mechanism1. The well-established cell - to - cell signaling process in bacteria is known as quorum sensing through chemical signaling molecules2-5. Recently, another cell- to - cell communication process based on ion channel mediated electrical signaling6 has also been observed. In this article, we propose a novel approach to explain the role of coherence and phase synchronization in the cell – to – cell bacterial communication. The observable long – range coherent electrical signaling is species independent and it is caused by membrane – potential - dependent modulation of tumbling frequency7-9. Moreover, noise can play a constructive role in enhancing the synchronization of chaotic bacterial communication systems and noise associated with the opening and closing the gate of ion channel induce small kinetic viscosity that make a wave-like pattern in concentration profile of quorum sensing.

Vessel recruitment and derecruitment mechanism and paradoxical behaviour of vasoconstriction during ischaemia

In this paper, we introduce mathematical aspect of recruitment and derecruitment mechanism of blood vessels acting in such a way as to preserve physiological values of the capillary pressure and perspective of pressure drop effect which has been pointed out by a series of studies documenting a paradoxical vasoconstriction during ischaemia.

Numerical aspect of Predator-Pray Model

In a closed eco-system, there are only two types of animals: the predator and the prey. They form a simple food-chain where the predator species hunts the prey species, while the prey grazes vegetation. The size of the two populations can be described by a simple system of two nonlinear first order differential equations formally known as the Lotka-Volterra equations, which originated in the study of fish populations of the Mediterranean during and immediately after World War I. Here, we study numerically this nonlinear parabolic evolution problem and compare the result of various numerical schemes.