Title A talk about beer, wine, and pizza Amelia Gontar (Flinders University) Amelia Gontar Contributed Talks 11:00:00 2017-09-26 The yeast \textit{Saccaromyces cerevisiae}, often called bakers' yeast, is used in the production of bread, wine, ale, and -- of course -- pizza dough. \textit{S. cerevisiae} can grow via the budding of yeast cells, or by forming chains of unseparated cells called pseudohyphae. Pseudohyphal growth is thought to be triggered by nutrient deprivation, but is not yet completely understood. Hence, quantifying the often complex shape patterns exhibited by pseudohyphae is of interest. In this project, pseudohyphal growth is analysed using two-dimensional top-down binary images. The colony morphology is characterised using clustered shape primitives -- shape descriptors learned automatically from the data. Features based on clustered shape primitives are used to build a classifier to distinguish between yeast colonies based on strain, nutrient concentration, and by both strain and nutrient concentration simultaneously. The classifier uses only a small set of features that are learned automatically from the data, and does not require a list of predefined features or \textit{a priori} knowledge about the data sets. The resulting classifier predicts the strain and nutrient concentration of the yeast colonies with an accuracy of~$0.969$ ($\text{SD}=0.041$), demonstrating that yeast colonies exhibiting pseudohyphal growth can be characterised successfully based on their shape patterns.