within-field variation of wheat yield and spatial pattern of weed density and soil nitrogen were evaluated by geostatistical methods. samples were taken from a 90×120 m area located in a 3.8 ha wheat field. soil nitrogen content and weed density at tillering and wheat yield at maturity were measured in 1 m2 plots located at the center of 10×10 m grids. grain yield was varied between 1.5-4.9 t h...

Infectious diseases often spread as spatial epidemic outbreak waves. A number of model studies have shown that such spatial pattern formation can have important consequences for the evolution of pathogens. Here, we show that such spatial patterns can cause cyclic evolutionary dynamics in selection for the length of the infectious period. The necessary reversal in the direction of selection is e...

A design pattern description is much more complex than a semi-formal solution, often restricted to a class diagram. Applying a pattern mainly depends on the solution specification but a lot of useful information can be found into other items. Neglecting variants of the main solution the pattern engineer might explain can be detrimental to the pattern itself because, most of the time, they affec...