Most existing works on riddling assume that the underlying dynamical system possesses an invariant subspace. We find that, under arbitrarily small, deterministic perturbations, a riddled basin is typically destroyed and replaced by fractal ones, a catastrophe of riddling. We elucidate, based on analyzing unstable periodic orbits, the dynamical mechanism of the catastrophe. Analysis of the criti...

 Schemes that make use of ex-ante risk transfer instruments, including indemnity and index-based insurance and insurance-linked securities (e.g. catastrophe bonds, catastrophe swaps, and weather hedges).  Schemes where the public sector, the private sector or both (as public-private partnerships) play a role in their set up and operation.  Schemes that have been implemented (fully operationa...

This paper addresses the infrared (IR) catastrophe appearing in quantum field theory. IR catastrophe is formulated and studied in operator theory, characterized by the Carleman operator. The theory presented in this paper is applied to the Hamiltonian of the model describing a non-relativistic electron coupled with a quantum field of phonons or polaritons in the light of mathematics as well as ...

On Sunday 1 August 2004, at noon, in a well-known supermarket (Ycua Bolaños) on the outskirts of Asunción, the capital of Paraguay, there was a violent explosion in the fast-food section. This was caused by a build-up of gases in the chimneys of the kitchen. The flames spread rapidly through the air ducts, causing a huge fire throughout the supermarket. When the fire broke out, there were about...

n page 1163, Gerhardt et al. present a mechanism to explain the function of VEGF in angiogenesis. Their findings implicate a specialized cell at the tips of vessels in guiding the growth of new sprouts, with cell mass provided by the division of different cells that lie further back. The authors examined angiogenesis in mice retina. Retinal O Tip cell (green) filopodia follow VEGF-A–expressing ...