Event

Bioengineering Seminar Series: Keith Herold

Friday, February 13, 2015
9:00 a.m.
Pepco Room (1105), Jeong H. Kim Engineering Building
Professor Ben Shapiro
benshap@umd.edu

Keith Herold
Associate Professor
Fischell Department of Bioengineering
University of Maryland

The Intersection of Mechanical and Bioengineering

This lecture will highlight two research efforts, one from my Energy Systems phase and another from the last few years. The first one was an experimental investigation of the effect of surfactant additives on the performance of absorption refrigeration systems. Although many previous investigators had attacked this problem, there was no consensus in the community about the mechanism of performance improvement. Our work, which involved four distinct experimental investigations, was successful in shining a defining light on the physics of the surfactant in this system and the results were somewhat unexpected. The difficulty of accepting new ideas, even when the experimental data are right in front of you, is an important note from this effort. The second research effort which will be highlighted revolves around the use of PCR plus melt curve analysis of bacterial 16S DNA sequences to identify species in a clinical sample. The basic method is relatively well understood in the research community. However, the method has several limitations and one is that the PCR step is exquisitely sensitive to contamination. Although present at low levels, commercial DNA polymerase is known to carry residual bacterial DNA contamination. For many applications, this contamination is sufficiently low that it is not an issue. However, if you attempt to amplify low target concentrations, the polymerase contamination eventually becomes a limiting factor. We investigated this method from several angles and the results provide a much clearer view of the limitations and some ideas of how one might be able to reduce the contamination issue in future.