Effects of non-perturbatively improved dynamical fermions in UKQCD simulations

We present results for QCD with 2 degenerate flavours of quark using a non-perturbatively improved action on a lattice volume of $16^3\times32$ where the bare gauge coupling and bare dynamical quark mass have been chosen to maintain a fixed physical lattice spacing and volume (1.71 fm). By comparing measurements from these matched ensembles, including quenched ones, we find evidence of dynamical quark effects on the short distance static potential, the scalar glueball mass and the topological susceptibility. There is little evidence of effects on the light hadron spectrum over the range of quark masses studied ($m_{\pi}/m_{\rho}\geq 0.60$).Comment: Lattice 2000 (Spectrum and quark masses), 4 pages, 5 figure

Case studies in SenseCam use for cognitive stimulation therapy in early-stage dementia.

Estimates suggest that Ireland will have 50,000 people with dementia by 2016 and over 100,000 by 2036. Combined with European total costs are estimated in 2005 at €130 billion. As dementia is incurable there is a real need to support the existing dementia health care practices and carers by innovative technology use. Using technology to improve mental health of the people with dementia is one way of such support. This research explores intervention which uses Microsoft SenseCam images within the principles of Cognitive Stimulation Therapy (CST) to engage people with early stage dementia in meaningful discussion. This SenseCam intervention, like the CST approach, aims at general enhancement of quality of life and global cognitive and social functioning

SenseCam intervention based on cognitive ctimulation therapy framework for early-stage dementia.

Estimates suggest that Ireland will have 50,000 people with dementia by 2016 and over 100,000 by 2036. Combined with European total costs estimated in 2005 at €130 billion. In the absence of a cure for dementia there is a real need to develop pervasive, user-centered technologies to enhance the well-being and quality of life of people with dementia. This study explores the use of Microsoft SenseCam images within the principles of Cognitive Stimulation Therapy (CST) to engage people with early stage dementia in meaningful discussion. The SenseCam intervention, like the CST approach, is aimed at general enhancement of quality of life and global cognitive and social functioning

Approximate actions for dynamical fermions

Recent developments and applications of approximate actions for full lattice QCD are described. We present first results based on the stochastic estimation of the fermion determinant on $12^3\times 24$ configurations at $\beta=5.2$.Comment: 3 pages, Latex, no figures, Contribution to Lattice 97, The XV International Symposium on Lattice Field Theory, Edinburgh 22-26 July 199

Strangeness-exchange interactions at high energies

In Chapter 1 we discuss the importance of a study of high energy strangeness-exchange reactions in elucidating the exchange mechanisms and symmetry properties of meson-baryon scattering. The cross-section and polarisation data for KN→πΣ, Δ and πKN→πΣ, Δ are reviewed in Chapter 2. An exchange-degenerate poles with weak cuts model for the data is proposed, and the resulting successful polarisation and unsuccessful cross-section descriptions are discussed. The model's failure to reproduce the well-known line reversal cross-section inequality at intermediate energies is interpreted in terms of low energy resonance effects. A unified treatment of non-zero exotic exchange processes and line reversal symmetry violation in terms of Regge-Regge cuts is presented in Chapter 3. After a theoretical appraisal of a multiple scattering approximation for these cuts we present explicit calculations of the exotic strangeness-exchange cross- sections for K(^-)p-π(^+)Σ(^-) and π(^-)p→K(^+)Σ(^-). It is shown that the small size of the data for these is not easily explained. Since we also show that the inclusion of non-leading cuts aggravates the disagreement between data and the leading cuts model, the usefulness of Regge-Regge cut descriptions at intermediate energies is called into question

Feasibility study of using the overlap-Dirac operator for hadron spectroscopy

We investigate a number of algorithms that calculate the quark propagators for the overlap-Dirac fermion operator. The QCD simulations were performed at beta = 5.9 with a lattice volume of 16**3*32.Comment: LATTICE99(Chiral Fermions) 3 pages, 2 figures. A problem with the incorrect definition of the overlap mass has been corrected. The results have changed, but not the conclusions of the pape

Unquenching the Schwinger Model (revised)

We study the quenched and unquenched lattice Schwinger model with Wilson fermions. The lowest non-trivial order of the systematic expansion recently proposed by Sexton and Weingarten is shown to allow good estimates of long distance physics from quenched configurations. Results for the static potential and the lowest bound state mass are presented.Comment: 4 pages, 2 figures, self-unpacking uuencoded compressed postscript Contribution to Lattice 95 [Revision: value corrected on p.3