Experimental making in multi-disciplinary research

For the past 3 years, Graham Whiteley has been using making in a project to develop a mechanical analogy for the human skeletal arm to inform the future development of prostheses and other artefacts. Other aspects of the work such as use of drawings and the use of a principled approach in the absence of concrete design goals have been documented elsewhere, this paper concentrates on the central role of making in the process. The paper will discuss the role of making in multi-disciplinary research; craft skills and resources appropriate to each stage of a practice centred research project in this area; the use of models in an iterative experimental investigation and the value of models in eliciting knowledge from a broad community of interested parties and experts.</p

First make something – principled, creative design as a tool for multi-disciplinary research in clinical engineering

Design provides a set of tools for exploring our world and these can give very different insights from the tools of the natural scientist or social scientist. The Art and Design Research Centre at Sheffield Hallam University is developing the use of creative practice at the centre of multi-disciplinary research and has demonstrated that this approach can bring significant results in areas of research which are more usually thought of thought of as science or engineering. This paper describes a 3-year project which has provided completely new ideas for the design of artificial limbs based on close analogies with human anatomy. The project was intended to look at very long-term developments but has also resulted in ideas for today's products and has changed the thinking of both clinicians and manufacturers. Investigative methods included iterative cycles of creative development and reflection; work with users including the production of video material to stimulate their thinking beyond the state of the art; and both qualitative and quantitative evaluation of design outcomes with scientific and clinical specialists.</p

Knowledge and the artefact

This paper discusses ways that knowledge may be found in or through artefacts. One purpose is to suggest situations where artefacts might be central to a narrative, rather than secondary to a text. A second purpose is to suggest ways that design and production of artefacts might be instrumental in eliciting knowledge. Four general situations are proposed: (1) Simple Forms - an artefact demonstrates or describes a principle or technique. (2) Communication of Process - artefacts arising from a process make the process explicit. (3) Artefacts Within the Research - artefacts are instrumental in advancing the research by communicating ideas or information. (4) Knowledge Elicited by Artefacts - artefacts provide a stimulus or context which enables information to be uncovered. .</p

Error bounds on block Gauss Seidel solutions of coupled\ud multiphysics problems

Mathematical models in many fields often consist of coupled sub–models, each of which describe a different physical process. For many applications, the quantity of interest from these models may be written as a linear functional of the solution to the governing equations. Mature numerical solution techniques for the individual sub–models often exist. Rather than derive a numerical solution technique for the full coupled model, it is therefore natural to investigate whether these techniques may be used by coupling in a block Gauss–Seidel fashion. In this study, we derive two a posteriori bounds for such linear functionals. These bounds may be used on each Gauss–Seidel iteration to estimate the error in the linear functional computed using the single physics solvers, without actually solving the full, coupled problem. We demonstrate the use of the bound first by using a model problem from linear algebra, and then a linear ordinary differential equation example. We then investigate the effectiveness of the bound using a non–linear coupled fluid–temperature problem. One of the bounds derived is very sharp for most linear functionals considered, allowing us to predict very accurately when to terminate our block Gauss–Seidel iteration.\ud \ud Copyright c 2000 John Wiley & Sons, Ltd

A Multidimensional Approach to Studying Cultural Differences & Coping Strategies in a Multinational Coalition Environment

Current and future coalition operations increasingly involve collaboration on operations beyond the traditional battlespace. The challenge is to communicate effectively among multinational teams and to understand each nation's developed communication culture. During multinational collaboration, communications are often via electronic networks. This, as a result, removes physical presence and rich context information with the important verbal, behavioural and cultural cues that are often vital to appropriately interpreting the content of the information. In addition, communication preferences, customs, variations in language use and other linguistic and cultural characteristics may create barriers between nations, even without electronic mediation. In this paper, we propose a multidimensional approach, which would capture major aspects of cross-cultural communication and provide a systematic and a comprehensive method for studying communication preferences and peculiarities in the light of cultural differences. More specifically, we propose to analyze data from cross-cultural, cognitive, and linguistic perspectives. Our approach will identify crucial elements involved in cross-cultural communication. Our approach will also discuss overall and individual strategies in collaborating, which can serve as a basis for training to improve multinational communication effectiveness

The 'Beeching Axe' and Electoral Support in Britain

Policy implementation has important electoral effects, but there is often a problem in determining if policy changes drive electoral behaviour or if the process works in reverse. To address this issue we exploit a unique natural experiment in Britain: the closure of thousands of train stations, known as the Beeching Cuts, on the eve of General Election of 1964. We use several statistical methods to show that policy implementation was unaffected by partisan considerations and therefore it can be regarded as an exogenous intervention. An individual level model of voting intentions from the first British Election Study conducted in 1963, and an aggregate model of party vote shares in the General Election of 1964 show that the closures significantly changed voting support for the Conservative party. The 1964 election was very competitive and the closures clearly contributed to the defeat of the incumbent government after 13 years of uninterrupted rule

Linear variance bounds for particle approximations of time-homogeneous Feynman-Kac formulae

10.1016/j.spa.2012.02.002Stochastic Processes and their Applications12241840-1865STOP

Error bounds and normalising constants for sequential monte carlo samplers in high dimensions

In this paper we develop a collection of results associated to the analysis of the sequential Monte Carlo (SMC) samplers algorithm, in the context of high-dimensional independent and identically distributed target probabilities. TheSMCsamplers algorithm can be designed to sample from a single probability distribution, using Monte Carlo to approximate expectations with respect to this law. Given a target density in d dimensions our results are concerned with d while the number of Monte Carlo samples, N, remains fixed. We deduce an explicit bound on the Monte-Carlo error for estimates derived using theSMCsampler and the exact asymptotic relative L2-error of the estimate of the normalising constant associated to the target. We also establish marginal propagation of chaos properties of the algorithm. These results are deduced when the cost of the algorithm is O(Nd2). © Applied Probability Trust 2014

Farm Management in Australia: The Way Forward

This paper summarises the outcomes of a National Workshop in Farm Management, 5-6 December 2002, organised by the University of Sydney, Faculty of Rural Management, Orange. At this Workshop leading farmers, industry leaders, corporate representatives, academics, researchers and extension officers explored the future of farm management (education, research and consultancy) in Australia. Major outcomes were that farm management practice is proceeding informally to undertake decisions supporting socially and ecologically friendly, sustainable commercial production agriculture. However the risks of lack of integration, a reductionist approach to only on-farm practice, stagnation of academic programs to respond to leading edge industry initiatives, as well as ill-defined boundaries for farm management research were identified. The analysis indicated that formal educational models, research and extension-consultancy frameworks of an holistic nature, and a multiple bottom line perspective, were appropriate avenues for the future development of farm management practice and research. Workshop participants perceived that a farm management strand emphasising business management rather than technology could be a better educational model. Also there was an emphasis in highlighting the importance of linked development and partnership amongst the different players. The Workshop created the conditions for development of networks among industry, education and consultative research.Farm Management,

Activation of the Listeria monocytogenes Virulence Program by a Reducing Environment.

Upon entry into the host cell cytosol, the facultative intracellular pathogen Listeria monocytogenes coordinates the expression of numerous essential virulence factors by allosteric binding of glutathione (GSH) to the Crp-Fnr family transcriptional regulator PrfA. Here, we report that robust virulence gene expression can be recapitulated by growing bacteria in a synthetic medium containing GSH or other chemical reducing agents. Bacteria grown under these conditions were 45-fold more virulent in an acute murine infection model and conferred greater immunity to a subsequent lethal challenge than bacteria grown in conventional media. During cultivation in vitro, PrfA activation was completely dependent on the intracellular levels of GSH, as a glutathione synthase mutant (ΔgshF) was activated by exogenous GSH but not reducing agents. PrfA activation was repressed in a synthetic medium supplemented with oligopeptides, but the repression was relieved by stimulation of the stringent response. These data suggest that cytosolic L. monocytogenes interprets a combination of metabolic and redox cues as a signal to initiate robust virulence gene expression in vivoIMPORTANCE Intracellular pathogens are responsible for much of the worldwide morbidity and mortality from infectious diseases. These pathogens have evolved various strategies to proliferate within individual cells of the host and avoid the host immune response. Through cellular invasion or the use of specialized secretion machinery, all intracellular pathogens must access the host cell cytosol to establish their replicative niches. Determining how these pathogens sense and respond to the intracellular compartment to establish a successful infection is critical to our basic understanding of the pathogenesis of each organism and for the rational design of therapeutic interventions. Listeria monocytogenes is a model intracellular pathogen with robust in vitro and in vivo infection models. Studies of the host-sensing and downstream signaling mechanisms evolved by L. monocytogenes often describe themes of pathogenesis that are broadly applicable to less tractable pathogens. Here, we describe how bacteria use external redox states as a cue to activate virulence