Bioinformatics Seminar

Wednesday, October 28, 2009
3:00 - 4:00
Room 457 Blocker

Josue Martinez
Texas A&M University
Department of Statistics

Use of Multiple Singular Value Decompositions to Analyze Complex Calcium Ion Signals


We compare calcium ion signaling (Ca2+) between two exposures; the data are present as movies, or, more prosaically, time series of images. We introduce novel uses of singular value decompositions (SVD) and weighted versions of them (WSVD) to extract the signals from such movies, in a way that is semi-automatic and tuned closely to the actual data and their many complexities. Our aim is to show how uses of multiple weighted and standard singular value decompositions can be used to detect, extract and clarify the Ca2+ signals. Our signal extraction methods then lead to simple although finely focused statistical methods to compare Ca2+ signals across experimental conditions. Moreover, we use these resulting signals to cluster cells and predict their behavior at differing points of the experiment.