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We study the finite-time blow-up in two variants of the parabolic-elliptic Keller-Segel system with nonlinear diffusion and logistic source. In $n$-dimensional balls, we consider \begin{align*} \begin{cases} u_t = \nabla \cdot…

Analysis of PDEs · Mathematics 2021-05-10 Tobias Black , Mario Fuest , Johannes Lankeit

This paper aims to develop numerical approximations of the Keller--Segel equations that mimic at the discrete level the lower bounds and the energy law of the continuous problem. We solve these equations for two unknowns: the organism (or…

Numerical Analysis · Mathematics 2022-07-25 Santiago Badia , Jesús Bonilla , Juan Vicente Gutiérrez-Santacreu

As it is well known, the parabolic-elliptic Keller-Segel system of chemotaxis on the plane has global-in-time regular nonnegative solutions with total mass below the critical value $8\pi$. Solutions with mass above $8\pi$ blow up in a…

Analysis of PDEs · Mathematics 2014-01-30 Piotr Biler , Ignacio Guerra , Grzegorz Karch

We consider the chemotaxis problem for a one-dimensional system. To analyze the interaction of bacteria and attractant we use a modified Keller-Segel model which accounts attractant absorption. To describe the system we use the chemotaxis…

Biological Physics · Physics 2017-02-15 Alex Vasilev

It is well-known that the two-dimensional Keller-Segel system admits finite time blowup solutions, which is the case if the initial density has a total mass greater than $8\pi$ and a finite second moment. Several constructive examples of…

Analysis of PDEs · Mathematics 2024-09-10 Charles Collot , Tej-Eddine Ghoul , Nader Masmoudi , Van Tien Nguyen

A generically observed mechanism that drives the self-organization of living systems is interaction via chemical signals among the individual elements -- which may represent cells, bacteria, or even enzymes. Here we propose a novel…

We establish criteria on the chemotactic sensitivity $\chi$ for the non-existence of global weak solutions (i.e. \textit{blow-up} in finite time) to a stochastic Keller--Segel model with spatially inhomogeneous, conservative noise on…

Analysis of PDEs · Mathematics 2023-09-01 Avi Mayorcas , Milica Tomasevic

We show that the Keller-Segel model in one dimension with Neumann boundary conditions and quadratic cellular diffusion has an intricate phase transition diagram depending on the chemosensitivity strength. Explicit computations allow us to…

Analysis of PDEs · Mathematics 2019-04-29 Jose A. Carrillo , Xinfu Chen , Qi Wang , Zhian Wang , Lu Zhang

In this paper, we consider a Keller-Segel type fluid model, which is a kind of Euler-Poisson system with a self-gravitational force. We show that similar to the parabolic case, there is a critical mass $8\pi$ such that if the initial total…

Analysis of PDEs · Mathematics 2021-08-11 Li Chen , Feimin Huang , Lingjun Liu

New model equations are derived for dynamics of self-aggregation of finite-size particles. Differences from standard Debye-Huckel and Keller-Segel models are: the mobility of particles depends on the configuration of their neighbors and…

Pattern Formation and Solitons · Physics 2009-11-11 Darryl D. Holm , Vakhtang Putkaradze

We study a Keller-Segel type chemotaxis model with a modified sensitivity function in a bounded domain $\Omega\subset \mathbb{R}^N$, $N\geq2$. The global existence of classical solutions to the fully parabolic system is established provided…

Analysis of PDEs · Mathematics 2015-05-26 Qi Wang

We investigate the point spectrum associated with travelling wave solutions in a Keller-Segel model for bacterial chemotaxis with small diffusivity of the chemoattractant, a logarithmic chemosensitivity function and a constant, sublinear or…

Spectral Theory · Mathematics 2017-12-01 P. N. Davis , P. van Heijster , R. Marangell

Colonies of bacteria grown on thin agar plate exhibit fractal patterns as a result of adaptation to their environments. The bacterial colony pattern formation is regulated crucially by chemotaxis, the movement of cells along a chemical…

Biological Physics · Physics 2013-05-24 Waipot Ngamsaad , Kannika Khompurngson

This paper is devoted to constructing approximate solutions for the classical Keller--Segel model governing \emph{chemotaxis}. It consists of a system of nonlinear parabolic equations, where the unknowns are the average density of cells (or…

Numerical Analysis · Mathematics 2024-02-13 Juan Vicente Gutiérrez-Santacreu , José Rafael Rodríguez-Galván

Chemotaxis is a fundamental guidance mechanism of cells and organisms, responsible for attracting microbes to food, embryonic cells into developing tissues, immune cells to infection sites, animals towards potential mates, and…

Quantitative Methods · Quantitative Biology 2018-06-26 K. J. Painter

We study the existence of steady states to the Keller-Segel system with linear chemotactical sensitivity function on a smooth bounded domain in $\mathbb R^N,$ $N\ge3,$ having rotational symmetry. We find three different types of…

Analysis of PDEs · Mathematics 2016-03-22 Oscar Agudelo , Angela Pistoia

Cells encounter a diverse array of physical and chemical signals as they navigate their natural surroundings. However, their response to the simultaneous presence of multiple cues remains elusive. Particularly, the impact of topography…

Analysis of PDEs · Mathematics 2026-03-10 Valeria Cuentas , Elio Espejo

We consider the Keller-Segel model of chemotaxis on one-dimensional networks. Using a variational characterization of solutions, positivity preservation, conservation of mass, and energy estimates, we establish global existence of weak…

Numerical Analysis · Mathematics 2018-05-03 Herbert Egger , Lucas Schöbel-Kröhn

A finite volume scheme for the (Patlak-) Keller-Segel model in two space dimensions with an additional cross-diffusion term in the elliptic equation for the chemical signal is analyzed. The main feature of the model is that there exists a…

Numerical Analysis · Mathematics 2012-08-02 Marianne Bessemoulin-Chatard , Ansgar Jüngel

We study a system of two coupled nonlinear parabolic equations. It constitutes a variant of the Keller-Segel model for chemotaxis, i.e. it models the behaviour of a population of bacteria that interact by means of a signalling substance. We…

Analysis of PDEs · Mathematics 2015-05-14 Jonathan Zinsl , Daniel Matthes
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