This week we finally submitted our paper on engineered oscillations in bacterial populations. This is something I've been working on with a colleague in Madrid, Angel Goni-Moreno, since he visited us in Manchester last year (in truth, he's been doing most of the work, although any delays have been entirely due to me).
In physics, an oscillator is a system that produces a regular, periodic "output". Familiar examples include a pendulum or a vibrating string. Linking several oscillators together in some way gives rise to synchrony -- for example, heart cells repeatedly firing in unison, or millions of fireflies blinking on and off, seemingly as one.
Oscillators are fundamental to biology, but they are also of interest to engineers, since they form the basis for counting (and synchronisation). Synthetic biology combines both disciplines, so the construction of oscillators within living cells is one of the main topics of interest in the field right now. However, until recently, most work has been restricted to single cells. In our paper, we have shown, in theory, how to engineer oscillations within populations of cells, using the "client-server" model familiar to computer scientists.
Update: the preprint version of the paper is here.
While writing the final draft, I was reminded of my brief contact with one of the founders of the field of theoretical biology. I first met Brian Goodwin in 2004, when I was still at the University of Exeter. He, along with Susan Blackmore, very kindly agreed to speak at the launch of a network I'd set up to encourage the study of complexity theory within the University. Best known in the broader community for his work on the evolution of complexity, Goodwin laid the foundations for recent research in synthetic biology with his seminal 1965 work on negative feedback. His later work focussed on the notion of a science of qualities (on which he spoke at our meeting), and when I first met him he was already formally retired, although still very active at Schumacher College, just down the road in Dartington. We also spent time chatting a year later, while we were both giving lectures at a summer school in Montpellier. I was struck most of all by his gentle nature and generosity of spirit, and we had the chance to discuss in greater depth the topics he'd touched on in his lecture.
Brian died just over a year ago; I first found out about his death while looking up references to give to my current Ph.D. student, who is now applying some of his ideas to the field of architecture. He had a great effect on me, and will continue to influence generations of students to come.