On the ultimate precision of meson mixing observables

Meson mixing is considered to be an ideal candidate for new physics searches. Current experimental precision has greatly increased over the recent years, excelling in several cases the theoretical precision. A possible limit in the theoretical accuracy could be a hypothetical breakdown of quark-hadron duality. We propose a simple model for duality violations and give stringent bounds on such effects for mixing observables, indicating regions, where future measurements of $\Delta \Gamma_d$, $a_{sl}^d$ and $a_{sl}^s$ would be clear signals of new physics. Finally, we turn our attention to the charm sector, and reveal that already a modest duality violation of about $20 \%$ could explain the huge difference between HQE predictions for D-mixing and experimental data.Comment: 37 pages, 9 figures. v2 (very belated) update to journal version (plus extended appendices

Using Movies to Probe the Neurobiology of Anxiety

Over the past century, research has helped us build a fundamental understanding of the neurobiological underpinnings of anxiety. Specifically, anxiety engages a broad range of cortico-subcortical neural circuitry. Core to this is a ‘defensive response network’ which includes an amygdala-prefrontal circuit that is hypothesized to drive attentional amplification of threat-relevant stimuli in the environment. In order to help prepare the body for defensive behaviors to threat, anxiety also engages peripheral physiological systems. However, our theoretical frameworks of the neurobiology of anxiety are built mostly on the foundations of tightly-controlled experiments, such as task-based fMRI. Whether these findings generalize to more naturalistic settings is unknown. To address this shortcoming, movie-watching paradigms offer an effective tool at the intersection of tightly controlled and entirely naturalistic experiments. Particularly, using suspenseful movies presents a novel and effective means to induce and study anxiety. In this thesis, I demonstrate the potential of movie-watching paradigms in the study of how trait and state anxiety impact the ‘defensive response network’ in the brain, as well as peripheral physiology. The key findings reveal that trait anxiety is associated with differing amygdala-prefrontal responses to suspenseful movies; specific trait anxiety symptoms are linked to altered states of anxiety during suspenseful movies; and states of anxiety during movies impact brain-body communication. Notably, my results frequently diverged from those of conventional task-based experiments. Taken together, the insights gathered from this thesis underscore the utility of movie-watching paradigms for a more nuanced understanding of how anxiety impacts the brain and peripheral physiology. These outcomes provide compelling evidence that further integration of naturalistic methods will be beneficial in the study of the neurobiology of anxiety

THE DISPERSAL OF CABBAGE ROOT FLY IN RELATION TO AGRICULTURAL PRACTICE

The study aimed to estimate the dispersal rate of wild cabbage root flies in agricultural systems, to test a migration hypothesis and the predictions of a computer simulation model. The dispersal rate was determined by a new method, from the age-grouping of wild flies instead of releasing marked culture flies. The mean distance dispersed was calculated from-the slope of density of captured flies on distance; the mean age was calculated from laboratory measurements of development at constant temperatures. A new method of male age determination was developed, based on the changes in pupal fat and testes colour. The published method of female age determination was improved to allow more rapid separation of nulliparous and parous flies. The values of the slope and intercept fitted to the-density- distance data were strongly correlated. A computer simulation demonstrated that random noise causes a progressive underestimation of the slope, as the catch decreases. The slope for gravid females reaches a limiting value of approxiamately 0.2, indicating a mean distance dispersed of 500m. A numerical integration suggests that 95% of the flies move less than 580m. There was no evidence of the female migratory phase, proposed by Finch & Skinner(1975), which was probably an artefact of the use of ANCS attractant. The dispersal rate was estimated at 49-165 m/day, compared with 29-87 m/day predicted by the simulation model. There was little evidence that dispersal alters with agricultural practice. A proportion of the first generation were found to delay emergence on one site, which may be connected with the planting of fodder brassica crops at midsummer.The Agricultural, Development & Advisory Service (Starcross) and The National Vegetable Research Statio

The numbers of Scottish businesses and economic policy

Recent constitutional changes in Scotland have not altered the emphasis on economic development, which is central to public policy. In common with the rest of the UK and the USA there has been an emphasis on small business policy for this purpose. In particular, there has been an attempt to improve the rate of business formation sponsored by Scottish Enterprise and Highlands and Islands Enterprise. As this policy has been in place now for seven years it is possible to look critically at the outcomes over five years of data to assess what progress, if any, is being made