We give the necessary and sufficient conditions for a gradient Ricci-Yamabe soliton with warped product metric. As physical applications, we consider solitons on generalized Robertson-Walker space-times standard static space-times.

Given a compact Riemannian manifold M , we consider a warped product M̄ = I ×h M where I is an open interval in R. We suppose that the mean curvature of the fibers do not change sign. Given a positive differentiable function ψ in M̄ , we find a closed hypersurface Σ which is solution of an equation of the form F (B) = ψ, where B is the second fundamental form of Σ and F is a function satisfying c...

A. Both bi-harmonic map and f -harmonic map have nice physical motivation and applications. In this paper, by combination of these two harmonic maps, we introduce and study f -bi-harmonic maps as the critical points of the f -bi-energy functional 1 2 ∫ M f |τ(φ)| dvg. This class of maps generalizes both concepts of harmonic maps and biharmonic maps. We first derive the f -biharmonic map ...

We prove an existence result for helicoidal graphs with prescribed mean curvature in a large class of warped product spaces which comprises space forms.

background & aim: the use of herbal extracts as safe and effective factors for eradicating of stores pests has attracted much attention. in this paper, the bio-effects of fumigation and repellent effects of essential oil of eucalyptus globolus were investigated on red flour beetle. experimental: in this study, the toxicity, fumigation and repellency contacts were assayed by topical applicat...