The use of organic and chemical materials to perform digital signal processing without electrical currents could be the next major technological revolution, say Northwestern professors Sotirios Tsaftaris and Aggelos Katsaggelos. Their research includes studying the use of DNA for digital signal processing, as DNA strands can be used to input and process elements, and DNA is an excellent medium for data storage. Digital samples can be recorded in DNA, which can be kept in a liquid form in test tubes to save space. DNA can also be easily replicated using common laboratory techniques, creating a database that could be easily searched, no matter how large. Over the past 10 years scientists and engineers have experimented with different materials for performing signal processing, possibly leading to a "not-so-electric future" of digital signal processing, according to Tsaftaris and Katsaggelos. For example, artist and scientist Cameron Jones discovered that fungi grown on CDs causes the optically recorded sound to be distorted by the fungi, and that the fungi growth patterns were dependent on the optical grooves recorded on the CD. Meanwhile, in 2005, a group of E. coli cells were modified to react to light and were able to perform edge detection of an image, a basic processing task.