Editorial
Martyn Amos
We are pleased to present this special issue of the International Journal of Unconventional Computing, which is dedicated to papers arising from a workshop held on July 5 2013, as part of the Unconventional Computation and Natural Computation (UCNC) conference held in Milan, Italy. UCNC is now a well-established meeting in the portfolio of conferences dedicated to “non-standard computation”, dating back to 1998. The 2013 conference was hosted by the Università degli Studi di Milano-Bicocca, and the Third Workshop on Biological and Chemical Information Technologies (BioChemIT) was organized by the COBRA project.
COBRA was a three-year initiative (2010-2013), supported by the European Commission to encourage and nurture research and training in the field of biological and chemical information technology. Fundamentally, the field seeks to harness the capabilities of natural and chemical systems. Rather than simply deriving inspiration from living systems, bio/chem IT researchers seek to directly use or construct these systems for the purposes of engineering and computation. Over the past few years, technological advances in chemistry, molecular biology, functional materials and engineering have brought biological and chemical information processing within our control. The ability to build, design and grow ICT systems that can exploit these processes will lead to revolutionary advances in the future [2].
The five papers in this issue represent a broad swathe of work, covering alternative computational substrates such as synthetic cell-like systems, chemical oscillators and slime mould.
The first paper, by Altamura, et al., presents experimental investigations into the construction of giant vesicles; large “containers”, in which (bio) chemical-based computations may be encapsulated. They demonstrate how such vesicles may be formed, and consider issues of “interfacing”, by showing how pores may be engineered in the vesicles themselves. This work lays the foundations for future research into such exciting topics as intelligent drug delivery and therapeutic “nano-bots”.
The second paper, by Rossi, et al., considers chemical computing using the well-known BZ reaction [3]. Coupled oscillators have been widely used for unconventional computation (e.g., [2]), and this paper investigates the dynamics of a chemical system made up of networked BZ droplets in a microfluidic environment. The authors perform numerical simulations in order to guide their experimental investigations, and together these suggest many possible future lines of enquiry into the global dynamics of larger-scale chemical communication.
The third paper, by Jones and Adamatzky, presents results in morphological computation – the use of physical, embodied properties of a system for the purposes of computation. Specifically, they study the construction of a virtual Physarum machine [1], a device made using a combination of the slime mould Physarum polycephalum (literal meaning: “many-headed”) and embedded environmental cues. The organism is capable of a wide range of computations on a surface, via growth and adaptation of its physical shape. In this paper, the authors present preliminary experimental results on the use of simulated slime mould to extract features of large datasets using only local interactions. The capabilities demonstrated suggest potentially interesting future applications in robotics and statistical analysis.
The fourth paper, by Bramanti, Santana-Bonilla and Rinaldi, considers quantum-dot cellular automata (QCA), which implement computations using electrostatic interactions between cells. Existing QCA frameworks place strong restrictions on the nature of the implementation of these devices, and this paper describes proposals for molecular-scale cells that would be feasible at room temperatures.
The fourth paper, by Bramanti, Santana-Bonilla and Rinaldi, considers quantum-dot cellular automata (QCA), which implement computations using electrostatic interactions between cells. Existing QCA frameworks place strong restrictions on the nature of the implementation of these devices, and this paper describes proposals for molecular-scale cells that would be feasible at room temperatures.
The final paper, by Konkoli, introduces the idea of “natural computability”: that is, what is the most natural form of computation realisable using an arbitrary physical system? By building on early work of Putnam, Konkoli formalizes this problem and suggests a possible resolution.
We thank the Editor-in-Chief, Andy Adamatzky, for the opportunity to publish the special issue, the European Commission for supporting the COBRA project, and the anonymous reviewers for their timely, clear and helpful assessments.
References
[1] Adamatzky, A. (2011) Physarum Machines: Computers from Slime Mould. World Scientific
Series on Nonlinear Science A.
[2] Amos, M., Dittrich, P., McCaskill, J. & Rasmussen, S. (2011) Biological and chemical
information technologies. Procedia Computer Science 7, 56-60, doi:10.1016/j.
procs.2011.12.019.
[3] Borresen, J. & Lynch, S. (2012) Oscillatory threshold logic. PLOS ONE 7(11): e49498,
doi:10.1371/journal.pone.0048498.
[4] Tóth, A., Gáspár, V. & Showalter, K. (1994). Propagation of chemical waves through capillary
tubes. J. Phys. Chem. 98, 522–531.