Coarse-grained simulations of intrinsically disordered proteins and surfaces (Gil)

Organisms exhibit an ability to form nano-structured hard tissues through biomineralisation processes which are not well understood, but suggest a vast range of potential applications. It has emerged that an important part of the biomineralisation process is the use of intrinsically disordered proteins (IDPs), though the nature of their role is not understood. IDPs have an interaction energy between their residues which is lower than that of globular proteins, favouring faster shifts between bound and unbound states, temporary secondary structure and lending itself to intrinsic disorder.

IDPs are less easy to categorise and understand on the basis of secondary structure; lack of fixed secondary motifs mean that they are also harder to simulate accurately, and novel simulation ideas are beginning to emerge. This project first aims to develop a suitable approach to simulation of IDPs, which brings the advantages of coarse-graining and accelerated sampling techniques to bear on the problem, and second aims to begin to explore the question of the role of IDPs in the biomineralisation process.

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A Theoretical Study of the Electrocaloric Effect in Relaxor Ferroelectrics Using a Spin Model (Matthew)

The Electrocaloric effect (ECE) is the observed temperature change of a polarisable material under an electric field applied in adiabatic and reversible conditions at a phase change[1]. Relaxor ferroelectrics are capable of producing a strong ECE for small applied field [2]. Here I explore the properties of a spin model of a relaxor system, examining the effects of disorder on the system at the ferroelectric to paraelectric transition and describe how such a model may be used to predict the strength of the ECE within a relaxor.

[1] Valant et al. Phys. Rev. B 81, 214110 (2010), [2] Pirc et al. J. Appl. Phys. 110, 074113 (2011)