Iva Tolic-Nørrelykke

math. In the final years I applied to a large number of conferences and summer schools. I wanted to learn about different fields of research in biology, and even more than that I enjoyed travelling the world (which was otherwise financially impossible). So I visited Italy, Hungary, Argentina, Israel, USA, Portugal, Denmark, and Australia. At a meeting in Argentina I learned about possibilities to combine biology and math. I decided to do my PhD in biomathematics, still at the University of Zagreb. I joined the theoretical chemistry group of Nenad Trinajstic at the Rudjer Boskovic Institute in Zagreb. While I worked on theoretical chemistry, my PhD advisor encouraged me to find a place where I could do theoretical biology. I read the Journal of Theoretical Biology, mainly in the library while visiting my parents, who lived in Zurich at the time, because this journal was not available at my home institute. Soon I found an intriguing topic: modeling of the cytoskeleton as tensegrity (tensional integrity) structures, similar to the sculptures of Buckminster Fuller and Kenneth Snelson. The mechanical stability of these sculptures relies on compression-resisting struts and tension-resisting ropes. In the cell, microtubules correspond to struts and actin cables to ropes. I wrote an e-mail to Ning Wang at the Harvard School of Public Health in Boston, saying that I would be interested in working with him for a year or two. He replied that I could come over and see whether it would work out. So I went to Boston, started a theoretical work on testing the tensegrity model, and attended a lot of lunch and dinner seminars that provided free pizza, because I had no salary for the first few months. After my PhD, I realized I did not want to do theory alone and decided to go back to experiments. Because of personal reasons, I got in touch with the optical tweezers group of Kirstine Berg-Sorensen and Lene Oddershede at the Niels Bohr Institute in Copenhagen. This was an excellent opportunity to learn how to manipulate the cells and the cytoskeleton with laser tweezers, as well as how to combine the approaches of physics and math to address problems in biology. Iva TolicNørrelykke