Five-dimensional gauge theory and compactification on a torus

We study five-dimensional minimally supersymmetric gauge theory compactified on a torus down to three dimensions, and its embedding into string/M-theory using geometric engineering. The moduli space on the Coulomb branch is hyperkaehler equipped with a metric with modular transformation properties. We determine the one-loop corrections to the metric and show that they can be interpreted as worldsheet and D1-brane instantons in type IIB string theory. Furthermore, we analyze instanton corrections coming from the solitonic BPS magnetic string wrapped over the torus. In particular, we show how to compute the path-integral for the zero-modes from the partition function of the M5 brane, or, using a 2d/4d correspondence, from the partition function of N=4 SYM theory on a Hirzebruch surface.Comment: 30 pages, 2 figures; v2: typos corrected, added references, JHEP versio

The potato late blight pathogen Phytophthora infestans and other pathogenic oomycota

Potato late blight, caused by a member of the Oomycota, Phytophthora infestans (Mont.) De Bary, is one of the most important and devastating diseases of potato (Solanum tuberosum). The pathogen attacks both foliage and tubers, and spreads rapidly through host tissues, thereby causing a destructive necrosis. P. infestans is a hemibiotrophic pathogen with a rather narrow range of hosts, all of them members of the Solanaceae. The crop plants, potato and tomato (Lycopersicon esculentum), are the economically most important hosts. The first late blight epidemic in Europe in 1845 had disastrous effects on potato production. P. infestans spread over Europe within 1 year and was found in most potato-growing areas of the world soon thereafter. In Ireland the potato crop was destroyed in two successive years, leading to a famine. As a consequence, about one and a half million people died and another million emigrated, mainly to the United States. De Bary described the life cycle of the potato late blight pathogen and named it Phytophthora ("plant destroyer") infestans