Two human pathogenic bacteria, Staphylococcus aureus CIP 68.5 and Pseudomonas aeruginosa ATCC 9025, were adsorbed onto surfaces containing Ti thin films of varying thickness to determine the extent to which nanoscale surface roughness influences the extent of bacterial attachment. A magnetron sputter thin film system was used to deposit titanium films with thicknesses of 3, 12, and 150 nm on glass substrata with corresponding surface roughness parameters of R(q) 1.6, 1.2, and 0.7 nm (on a 4 microm x 4 microm scanning area). The chemical composition, wettability, and surface architecture of titanium thin films were characterized using X-ray photoelectron spectroscopy, contact angle measurements, atomic force microscopy, three-dimensional interactive visualization, and statistical approximation of the topographic profiles. Investigation of the dynamic evolution of the Ti thin film topographic parameters indicated that three commonly used parameters, R(a), R(q), and R(max), were insufficient to effectively characterize the nanoscale rough/smooth surfaces. Two additional parameters, R(skw) and R(kur), which describe the statistical distributions of roughness character, were found to be useful for evaluating the surface architecture. Analysis of bacterial retention profiles indicated that bacteria responded differently to the surfaces on a scale of less than 1 nm change in the R(a) and R(q) Ti thin film surface roughness parameters by (i) an increased number of retained cells by a factor of 2-3, and (ii) an elevated level of secretion of extracellular polymeric substances.

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In general few components are reused as they are. Often, available components are incompatible with what is required. This necessitates component adaptations or the use of adapters between components. In this paper we develop algorithms for the synthesis of adapters, coercing incompatible components into meeting requirements. We concentrate on adapters for concurrent systems, where adapters are able to resolve synchronisation problems of concurrent components. A new interface model for components, which includes protocol information, allows us to generate these adapters semi-automatically.

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Service-Oriented Computing (SOC) is an emerging paradigm for developing software systems that employ services. Presently there is already much research effort in the areas of service discovery and orchestration, business process modelling, and the semantic web. While these are all important aspects for moving towards the pervasive adoption of SOC, most existing work assumes the existence of black box services, with little attention given to how such services might be developed in a systematic manner. Furthermore, a precise description of what constitutes a service-oriented system is yet to be formally defined, and the overall impact of service-orientation on the software design process is not well understood. Therefore, this work presents a formal model covering design artefacts in service-oriented systems and their structural and behavioural properties. The model promotes a better understanding of service-oriented design concepts, and in particular, enables the definition of software metrics in an unambiguous, formal manner. Defining such a model and metrics is an initial step towards deriving a comprehensive service-oriented software design methodology.