Macroeconomics

Linguistics

Philosophy

Zero (linguistics)

Receptor

Economics

Biochemistry

Bounded function

Chemotaxis

Sublinear function

Physics

Mathematics

Domain (mathematical analysis)

Mathematical analysis

Combinatorics

Chemistry

Topology (electrical circuits)

Production (economics)

Nonlinear Analysis

We study this zero-flux attraction–repulsion chemotaxis model, with linear and superlinear production g for the chemorepellent and sublinear rate f for the chemoattractant: (♢)ut=Δu−χ∇⋅(u∇v)+ξ∇⋅(u∇w)in Ω×(0,Tmax),vt=Δv−f(u)vin Ω×(0,Tmax),0=Δw−δw+g(u)in Ω×(0,Tmax).In this problem, Ω is a bounded and smooth domain of Rn, for n≥1, χ,ξ,δ>0, f(u) and g(u) reasonably regular functions generalizing the prototypes f(u)=Kuα and g(u)=γul, with K,γ>0 and proper α,l>0. Once it is indicated that any sufficiently smooth u(x,0)=u0(x)≥0 and v(x,0)=v0(x)≥0 produce a unique classical and nonnegative solution (u,v,w) to (1), which is defined in Ω×(0,Tmax), we establish that for any such (u0,v0), the life span Tmax=∞ and u,v and w are uniformly bounded in Ω×(0,∞), (i) for l=1, n∈{1,2}, α∈(0,12+1n)∩(0,1) and any ξ>0, (ii) for l=1, n≥3, α∈(0,12+1n) and ξ larger than a quantity depending on χ‖v0‖L∞(Ω), (iii) for l>1, α∈(0,12+1n)∩(0,1), any ξ>0, and in any dimensional settings. Finally, an illustrative analysis about the effect by logistic and repulsive actions on chemotactic phenomena is proposed by comparing the results herein derived for the linear production case with those in Lankeit and Wang (2017).

Boundedness in a chemotaxis system with consumed chemoattractant and produced chemorepellent