Experimental research

Starling flocks

We developed a novel co-moving 3D system, i.e. a system of three high-speed synchronized cameras, inspired by the human ability to follow the trajectory of a target with a coordinate movement of the eyes: cameras are coupled with rotational stages that drive a controlled rotation of all the cameras in the same direction and at the same rotational speed. With the rotation of the cameras we overcome the limitations of standard static systems that restrict the duration of the collected data to the short interval of time in which targets are in the cameras common field of view.

With experimental data-taking campaigns on starling flocks, we checked the feasibility of the experiment with the co-moving set-up [article], which proved to be easy to mount and easy to calibrate in the field. The data collected in the field confirmed that with the co-moving strategy we can actually track the flocks significantly longer than with a standard static system, as we show in the video below, where we compare in terms of time duration the trajectories acquired with the dynamic system, highlighted in light blue, and the trajectories that we would have acquired using a standard static system, highlighted in red.

Insect swarms

Alongside our well-established field experiment of midge swarms, during RG.BIO we initiated a new line of research on lab-adapted malaria mosquitoes, Anopheles Gambiae. We perform 3D swarming experiments in a large cage (a room 5mx3m, 2.5m high) hosted at Spaccapelo lab (Department of Medicine and Surgery of Perugia University), where mosquitoes are reared. In the swarming arena, we artificially reproduced swarming stimuli: two lines of lights fade out at a specific time of the day to mimic sunset, a black and white cardboard square serves as a swarming marker. The camera is equipped with a 3D camera system and it is illuminated with near-infrared lamps, to provide sufficient visibility in the low-light conditions of sunset.

As in many other insects, swarming in mosquitoes plays a crucial role for mating: at sunset and sunrise, males congregate over a common marker to facilitate encounters with females, which enter the swarm very briefly and only to mate. With our 3D setup we collected data on large swarms, up to 400 individuals, for long time (up to 30 seconds) at 80fps, that we used to characterize these swarms, [article]. By releasing a few females in the arena, once swarming activity began, we were able to identify male-female encounters and to document male-male competitions within the swarm, as shown in the video.

Cell colonies

With the idea of exploring new universality classes, within RG.BIO we started a new line of research on cell colonies, human bone marrow stromal cells (BMSC), in collaboration with the Department of Molecular Medicine of Sapienza University of Rome.

We collect data on BMSCs proliferation in vitro through long lasting time-lapse microscopy of single-cell derived colonies, reconstructing the full lineage of single-cell derived colonies up to the seventh generation [article], as shown in the video.  By seeding the plate at very low densities, we are able to only select colonies that derive from single, well-isolated cells and that never get in contact with each other, so that we are certain of the clonal nature of each colony. To ensure unequivocal identification of cells and mitosis, we developed a custom semi-automatic software that allows manual tracking of individual cells.

Time-lapse of a BMSC colony. At the bottom, the time elapsed since the start of tracking. The change in color of the time counter indicates when tracking was interrupted.

Lineage of a colony. Black points mark mitoses. The colors of the connecting arcs represent elapsed time — lighter (green) indicates faster events, darker (blue) indicates slower ones.