Microscopic model of diffusion limited aggregation and electrodeposition in the presence of levelling molecules

A microscopic model of the effect of unbinding in diffusion limited aggregation based on a cellular automata approach is presented. The geometry resembles electrochemical deposition - ``ions'' diffuse at random from the top of a container until encountering a cluster in contact with the bottom, to which they stick. The model exhibits dendritic (fractal) growth in the diffusion limited case. The addition of a field eliminates the fractal nature but the density remains low. The addition of molecules which unbind atoms from the aggregate transforms the deposit to a 100% dense one (in 3D). The molecules are remarkably adept at avoiding being trapped. This mimics the effect of so-called ``leveller'' molecules which are used in electrochemical deposition

Warped Supersymmetric Unification with Non-Unified Superparticle Spectrum

We present a new supersymmetric extension of the standard model. The model is constructed in warped space, with a unified bulk symmetry broken by boundary conditions on both the Planck and TeV branes. In the supersymmetric limit, the massless spectrum contains exotic colored particles along with the particle content of the minimal supersymmetric standard model (MSSM). Nevertheless, the model still reproduces the MSSM prediction for gauge coupling unification and does not suffer from a proton decay problem. The exotic states acquire masses from supersymmetry breaking, making the model completely viable, but there is still the possibility that these states will be detected at the LHC. The lightest of these states is most likely A_5^XY, the fifth component of the gauge field associated with the broken unified symmetry. Because supersymmetry is broken on the SU(5)-violating TeV brane, the gaugino masses generated at the TeV scale are completely independent of one another. We explore some of the unusual features that the superparticle spectrum might have as a consequence.Comment: 21 pages, Latex, version to appear in Phys. Rev.

Wheat diseases in Western Australia

DISEASES caused by pathogenic organisms can seriously affect the yield of wheat. Some diseases are comparatively rare whereas others occur over a large area of the wheatbelt year after year

Lattice QCD with mixed actions

We discuss some of the implications of simulating QCD when the action used for the sea quarks is different from that used for the valence quarks. We present exploratory results for the hadron mass spectrum and pseudoscalar meson decay constants using improved staggered sea quarks and HYP-smeared overlap valence quarks. We propose a method for matching the valence quark mass to the sea quark mass and demonstrate it on UKQCD clover data in the simpler case where the sea and valence actions are the same.Comment: 15 pages, 10 figures some minor modification to text and figures. Accepted for publicatio

Trust, professionalism and regulation: a critical comparison of Medicine and Law

Background & Aims: Trust, professionalism and regulation are complex social phenomena, which are contextually dependent and dynamic. This project aims to explore the concept of ‘trust’ in Law and Medicine - questioning what it means to be a ‘trustworthy’ professional and how these understandings relate to ideas of professionalism and regulation. Methods: This study draws on a comprehensive review of the literature and interviews with thirty participants from within, or related to, the UK legal and medical professions. Participants included practitioners, those creating and implementing policy, and public representatives. Data was analysed using the ‘logics approach’ from Political Discourse Theory (PDT). This helped us draw out taken-for-granted ideas and beliefs about trust, professionalism and regulation and expose these to critique. Results: Participants highly valued patient/client trust, seeing it as fundamental to the functioning of their professional ‘service’. Trust was seen as attributed primarily to the individual practitioner and maintained through demonstrating measurable ‘professionalism’. Practitioners were understood to be individually responsible for preserving their image as a ‘good professional’, via evidencing their ‘professionalism’ to the patient/client and the regulator. Discussion: Current ways-of-thinking about trust permitted trust in individuals to be maintained, even when trust in the professions as a whole was challenged. However, for medical professionals particularly, this was predicated on a need to ‘evidence’ that one was a ‘good professional’ through intensive and continual regulation. This created an increased dependency on a ‘trust-industry’ of regulatory bodies and systems. This project critically questions how regulation shapes and impacts trust in the professions. It is a problem-driven approach, which seeks to break with current patterns of thinking and question: ‘what might be possible instead?’ This opens up an ideological space and new viewpoints, whereby audiences are encouraged to consider future change