Microwave surface resistance in MgB2

Measurements of the temperature dependence of the surface resistance at 3 GHz of 100 micron size fragments of MgB2 separated powder are presented and discussed. The microwave surface resistance data are compared to experimental results of Nb, Bi2Sr2CaCu2O8+δ (BSCCO) and theoretical predictions of s-wave weak coupling electron-phonon theory (BCS)

Spatial structure, cooperation and competition in biofilms

Biofilm formation, in which cells form matrix-enclosed communities, is a major mode of microbial life. The study of biofilms has revealed vast complexity both in terms of their resident species composition and phenotypic diversity. Despite this complexity, theoretical and experimental work in the past decade has identified common principles for understanding microbial biofilms. In this Review, we discuss how the spatial arrangement of genotypes within a community influences the cooperative and competitive cell-cell interactions that define biofilm form and function. Furthermore, we argue that a perspective rooted in ecology and evolution is fundamental to progress in microbiology