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The aim of this thesis by prospective publication was to evaluate the comparative accuracy of screening technologies for the detection of COAG and other sight-threatening eye diseases. It incorporates 4 peer-reviewed publications: 1). Methodology and reporting of diagnostic accuracy studies of automated perimetry in glaucoma: evaluation using a standardised approach (Ophthalmic Physiol Opt. 2015; 35(3):315-23). This publication reported on an evaluation of the methodological and reporting quality of diagnostic accuracy studies of perimetry in glaucoma and determined whether there had been any improvement since the publication of the Standards for Reporting of Diagnostic. Accuracy (STARD) guidelines in 2003. The main findings were that methodological and reporting quality was sub-optimal and appeared not to have improved substantially following the development of the STARD guidance. 2). Development and validation of a new glaucoma screening test using temporally modulated flicker (Ophthalmic Physiol Opt. 2018; 38(6):617-628). This publication described the psychometric characteristics and diagnostic accuracy of the Accelerator 4-Alternative Forced-Choice Flicker Test prototype (A4FTp) for detecting Chronic open angle glaucoma (COAG). The performance of the A4FTp was also compared with standard screening tests of ocular structure and function (Frequency Doubling Technology (FDT) perimetry and iVue Spectral Domain Optical Coherence Tomography (SD-OCT). The time taken to complete the A4FTp was relatively short and initial results are promising. The diagnostic accuracy for the A4FTp was comparable to those of the FDT and SD-OCT for detecting COAG and we concluded that with further refinement the A4FTp could have role in glaucoma detection in the future. 3). Diagnostic accuracy of technologies for glaucoma case finding in a community setting (Ophthalmology. 2015;122(12):2407-15). This publication described a cross sectional, observational, community-based study to evaluate the diagnostic performance of the FDT, Moorfields Motion Displacement Test (MMDT), iVue SD-OCT and ocular response analyzer (ORA) used alone or in combination, for the detection of COAG. Diagnostic performance of individual tests gave acceptable accuracy for COAG detection. The best performing parameter was inferior RNFL thickness recorded using the SD-OCT. Although the low specificity of visual-function tests precluded their use in isolation, an acceptable performance was achieved by combining RNFL thickness analysis with visual function tests 4). Role of advanced technology in the detection of sight-threatening eye disease in a UK community setting (BMJ Open Ophthalmology 2019; 4:e000347). This publication extended the analysis described above to determine the performance of same screening tests for detecting sight-threatening eye disease in a cohort of elderly subjects recruited from primary care. The main finding was that a subset of screening tests (FDT, SD-OCT, together with a recorded visual acuity <6/12) was the most effective in detecting significant eye disease in this elderly population. The study provided useful preliminary data to inform the development of further larger, multi-center screening studies to validate this screening panel. The work described in this thesis makes a useful contribution to the evidence base on the use of imaging and visual function technologies to identify COAG and other sight-threatening eye diseases in at-risk populations and provides clear directions for future research this area.

The potato cyst nematodes (PCN), Globodera pallida and G. rostochiensis are economically the most important nematode problems of potatoes within the EU, costing the UK potato industry over £36 million based on yield loss and nematicides application. Historically, farmers within the UK have relied heavily on soil fumigant and granular nematicides for PCN control. However, increasing political pressure on pesticide usage means that alternative and sustainable strategies are required. Biofumigation, the suppression of soil borne pests and pathogens by biocidal compounds released when brassicaceous tissues are hydrolysed, offers a potential sustainable alternative in managing PCN. In this study, summer cultivated B. juncea and R. sativus reduced PCN population post-potato harvest. Eruca sativa proved to be cold tolerant following overwinter cultivation, but did not reduce PCN multiplication . Glucosinolate concentrations in the brassicas varied significantly between different plant regions and cultivation seasons. B. juncea leaves produced high 2-propanyl levels while R. sativus produced predominantly 4-methylsulfinylbutyl and 2-phenylethyl GSL in foliage and root respectively. Eruca sativa produced a blend of GSL in both above and below grown tissues, most of which were either low or non-ITC producing GSL. Metconazole application enhanced 2-propanyl GSL production in B. juncea tissues. Glucosinolate concentrations correlated positively with PCN mortality in the summer-cultivated experiments. In glasshouse experiments, sinigrin was significantly degraded in brassica cultivated soil pre- and post- incorporation of the brassicas. Positive relationships were observed between PCN mortality and microbial activity, while GSL concentration was found to be inversely related to microbial activity. Finally, the LD50 for B. juncea and R. sativus against PCN were determined in-vitro as 0.027/0.032 and 0.546/0.035 mg 1 ml- for leaf/root extracts respectively. This study has demonstrated that using B. juncea and R. sativus can play an important role in PCN management, particularly if included in an integrated pest management scheme in ware potato production.

We introduce a statistical exploration of the parameter space of the Munich semi-analytic model built upon the Millennium dark matter simulation. This is achieved by applying a Monte Carlo Markov Chain (MCMC) method to constrain the 6 free parameters that define the stellar mass function at redshift zero. The model is tested against three different observational data sets, including the galaxy K-band luminosity function, B −V colours, and the black hole-bulge mass relation, to obtain mean values, confidence limits and likelihood contours for the best fit model. We discuss how the model parameters affect each galaxy property and find that there are strong correlations between them. We analyze to what extent these are simply reflections of the observational constraints, or whether they can lead to improved understanding of the physics of galaxy formation. When all the observations are combined, the need to suppress dwarf galaxies requires the strength of the supernova feedback to be significantly higher in our best-fit solution than in previous work. We interpret this fact as an indication of the need to improve the treatment of low mass objects. As a possible solution, we introduce the process of satellite disruption, caused by tidal forces exerted by central galaxies on their merging companions. We apply similar MCMC sampling techniques to the new model, which allows us to discuss the impact of disruption on the basic physics of the model. The new best fit model has a likelihood four times better than before, reproducing reasonably all the observational constraints, as well as the metallicity of galaxies and predicting intra-cluster light. We interpret this as an indication of the need to include the new recipe. We point out the remaining limitations of the semi-analytic model and discuss possible improvements that might increase its predictive power in the future.

Room modes are a recognised problem in small critical listening rooms and are known to cause colouration of sound reproduced within them. Investigations on the causes and solutions for this problem have been carried out for some time. Interest in the topic has extended to loudspeaker manufacturers who have mainly concentrated in developing methods for controlling the loudspeaker-room interaction in order to ameliorate low frequency reproduction. Compared to objective work on passive and active control methods, the study of the subjective perception of room resonances has been somewhat neglected. Available publications mostly concern the effects of single resonances, which are perhaps not fully representative of conditions as experienced in real rooms. A study into the subjective perception of room modes is presented. The experimental methodology employs psychoacoustic techniques to study the perception of factors such as modal distribution, and effects of resonances on single tones. Results show that the subjective perception of room modes is strongly affected by temporal issues, and that changes exerted merely on magnitude frequency response are detectable but not likely to remove the effects of resonances for all listeners. Furthermore, it is shown that a reduction of the modal Q-factor, associated with a reduction of decay rates, has a significant effect in decreasing the detection of resonances. Q-factor difference limen were evaluated for three reference decay characteristics corresponding to reference Q-factors of 30, 10 and 1. The limen were 6±2.8, 10±4.1 and 16±5.4 respectively, meaning that detection of changes to modal decay decreases with decreasing decay time. These results may be used to define more perceptually relevant design guidelines for critical listening environments, and indicate target criteria for control techniques used in room correction. The outcomes of this investigation will have repercussions on the design of better rooms for critical listening.