March 23 – 27

Monday, March 23rd

Seminar: The evolution of resistance to Bt corn in the Western Corn Rootworm
Lex Flagel – Evolutionary Biologist from Monsanto
RNS 410 4:00 PM

The Western Corn Rootworm (WCR) is a major corn pest leading to annual economic losses of more than 1 Billion dollars in the US. Monsanto produces transgenic corn varieties expressing insecticidal toxins derived from the bacterium Bacillus thuringiensis (Bt corn) that are widely used to control WCR. Because of their effectiveness, these Bt corn varieties have grown popular in the past decade. However, widespread cultivation of Bt corn places intense selection pressure on WCR to evolve resistance. Instances of resistance to Bt toxins in WCR have been reported since 2011. I will describe our strategy for combating the spread Bt resistance. Specifically, how we apply principles from genetics and evolutionary biology to understand resistance and to improve insect resistance management strategies.

MSCS Colloquium:  A Provably “Jam–proof” Algorithm for (Almost) Filling Space
Christopher Ennis, Normandale Community College
I will describe, demonstrate, and prove a few things about an elegantly simple algorithm, due to John Shier, for the disjoint but otherwise random placement of successively smaller copies of an arbitrary shape inside a larger bounded region (“the frame”).
After presenting several aesthetically pleasing examples of the algorithm at work, I’ll give a simple rigorous proof of the one-dimensional version of Shier’s conjecture. Using the one-dimensional proof as a springboard, I’ll sketch the outline of a proof for the two-dimensional case, in which disjoint circular discs are placed randomly within a circular frame. The methods used involve nothing beyond familiar concepts from elementary calculus. I’ll also mention some open questions, suitable for investigation by undergraduates.
3:30 p.m. RNS 310 (cookies and conversation at 3:15p.m.)

Tuesday, March 24

No Seminars

Wednesday, March 25

Physics Colloquium
From Protons to Pictures: A Physicist in Medical Imaging
Kay Pelletier ’10, Ph.D. Candidate, Biomedical Engineering at Mayo Graduate School
2:00 pm RNS 210

Biomedical imaging research brings together physicists, engineers, biologists and chemists to develop techniques that directly impact patient care. Technological advances have made it possible to create images at scales from single molecules to the whole body. Medical images are used for a wide range of purposes from mapping brain function, diagnosing disease, measuring blood flow and metabolism, visualizing cellular function and more. This talk will introduce how medical images are made, and how they are used in clinical practice. A technique developed by physicians, engineers, physicists and mathematicians is capable of quantifying the mechanical properties of biological tissue. My research uses this technique, called Magnetic Resonance Elastography (MRE) to investigate the stiffness of tumors. It is commonly known that tumors are stiffer than the surrounding normal tissue. This talk will describe how the tumor mechanical properties change with successful treatment, and how this can be used to improve the outcome for the patient.

Thursday, March 26

What: Informal Conversation about Pathways and Possibilities in Science Education
Where: RNS 426
When: Thursday, March 26, 11:30-12:30

Are you planning to major in science?  Do you enjoy spending time with youth?  You can probably think of a teacher you’ve had who made a difference; have you ever thought you might be interested in teaching others?

If so, it’s a good time to start thinking about opportunities in science education.  At St. Olaf, you can become a licensed middle or high school science teacher.  Besides being a fulfilling job, science teachers are in demand.  While there are many paths to becoming a science teacher, there are some big advantages to the licensure program at St. Olaf.

If you’d like to talk about what it’s like to be a science teacher and about possibilities and pathways to a teaching license, please drop in for an informal conversation with Emily Mohl, assistant professor in biology and education.

Questions?  Contact Emily Mohl,, RNS 432.

Friday, March 27

No Seminars