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Through a series of close readings of six Hollywood science fiction films of the 1950s, this thesis investigates the genre's representation and rendering of social and political concerns specific to the historic moment through its repurposing and reimagining of mythic and archetypal narrative structures, conceptualised here as a corresponding phenomenon to the growth of interest in those areas of study within the academic community, for instance in the work of Campbell, Jung, and Frye. It establishes how this relationship is articulated in the form of a particular melancholic tone and attitude that contrasts with the ostensible stability and triumphalism of both the genre and American culture in this period, a melancholy that is apparent in the contemporary commentary of I.F. Stone and in the cybernetic theorising of Norbert Wiener. With an inductive method that connects formal and structural readings, grounded in a consideration of cinematic language and generic conventions, I address these recurring thematic concerns of the contemporary cultural and intellectual milieu that are also apparent in this selection of films. The thesis thus identifies direct adaptations of, and homologies with, prominent constellations of academic and popular thought in America at this time as they emerge through the corpus, and thereby argues for the value of such comparative analysis. The readings therefore address such phenomena as the popularity of Freudian psychology, the development of cybernetics, and the evolution of structural thought, identifying a clear bridge between these immediate historic and cultural concerns, and the functioning of the science fiction genre in cinema at this point in its own evolution. In so doing, it also lays the groundwork for a new history of science fiction film, suggesting a triangulation of the genre's relationship with parallel social, cultural, and political trends through consideration of the mythic and the melancholic.

Upon removal from a reactor spent nuclear fuel is placed into water storage for a period of time since water provides both a decay heat sink and radiation shielding. In the UK this fuel has traditionally been reprocessed however the decision has been made that this will cease in 2018 in favour of an open fuel cycle and direct disposal to a degological disposal facility, although this is not expected to be available until 2075. Current experience with pond storage has found that fuel can be safely stored in caustic dosed ponds for at least 25 years and therefore the current plan is to extend water storage until around 2040, however how the fuel will be stored for the remaining 35 years is yet to be decided. One option that is being considered is the use of dry storage which is being used successfully in the USA for the storage of fuel from Light Water Reactors. One of the most important factors when utilising dry stores is an effective drying step and this PhD is aiming to look at this area in particular. Commercial drying methods have been developed for use with Zircaloy and aluminium clad fuels however this PhD intends to develop a method that can be used to dry Stainless Steel clad fuels such as those used in the UK's Advanced Gas Reactors (AGR). Since intact AGR fuel has yet to be examined following storage the first part if this thesis looked at preparing samples for later macro scale testing. Samples were treated to induce defects known to be of concern and analysed with the conclusion being that bound water is of no concern for drying operations and can be disregarded when preparing samples. Since AGR is known to have failed by stress corrosion cracking water trapped within microcracked pins is a likely issue. A section of tube was prepared by compression and boiling in magnesium chloride which micro CT imaging found to have images of a similar size to known failures. This tube was prepared into a test piece for later testing. The second part of the thesis looks at macro scale testing using the test piece described above and a similar test piece with a 300 um pinhole. A multipurpose drying rig capable of vacuum drying and flowed gas drying was constructed. In the first phase of drying tests vacuum drying and flowed gas drying were compared using a test piece with a 300 um pinhole and the impact of different cover gas was assessed. vacuum drying was found to be significantly more effective than flowed gas drying with the type of cover gas having little impact. Most importantly this work guided further improvements to the rig. The second phase of this work carried out more detailed drying tests on vacuum drying and flowed gas drying and utilised the pinholed and cracked test piece. The greatest influencing factor on the drying rate (the rate at which water could be removed from inside the test piece) was found to be the water level inside the test piece with broadly similar rates being found in all conditions and with both test piece when the test piece was full. As the water level within the test piece dropped, vacuum drying quickly became more effective. This was not helped by considering energy usage. There was however a feeling that flowed gas drying was limited due to the pipework size. In the final phase of testing the ability to detect the point which all water was removed (the end point) from the test piece using online instrumentation was assessed. Currently a vacuum rebound test is used which is both time consuming and if flowed gas drying is being used requires additional plant equipment. It was found that dew point measurements appeared to give a relatively clear indication of the end point when for both vacuum drying and flowed gas drying. For vacuum drying only the measurement of mass flow and pressure also gave a reasonable indication of end point.

Birds are commonly used as biomonitors of environmental pollution, with most tests involving invasive or destructive sampling techniques. The need to develop and validate non-invasive techniques has long been recognised. From blood, eggs, feathers or guano, the last shows most promise in this field. However it constitutes both faecal and urinary excretions. The faecal component has serious analytical drawbacks from digestive processes and being comprised of both bio-available and unabsorbed components. In contrast the typically white urine part of guano represents substances emanating entirely from within the bird. Despite the analysis of urine (urinalysis) being widely and successfully used in mammals, its limited application to date in birds is at best misguided because it disregards the nature of avian urine. This thesis endeavours to show how the analysis of the (normally discarded) solid component of avian urine may provide a quantifiable measure of both environmental pollutant exposure and endogenous stress hormone concentrations in birds. The literature is reviewed with regard to birds as biomonitors of the environment and the use of non invasive sampling techniques, especially excreta collected from wild animals including birds. Avian renal physiology and urine composition is described with specific reference to current avian urinalysis methods and how these compare with the proposed use of avian urate spheres (AUS) for biomonitoring. It is also shown how the biomineralisation process of AUS formation is relevant to their collection, extraction and chemical analysis from bird guano. To investigate if AUS contents could be used as a measure of a bird’s environmental pollution exposure, concentrations of lead, copper and zinc, were determined in urate spheres from domestic chickens (Gallus domesticus) exposed to a soil contaminated by these metals. Furthermore an attempt was made to compare metal concentrations in AUS with eggs, feathers and whole guano from the same birds. The results suggested AUS contained higher levels of the contaminating metals in exposed birds compared to control birds. However the aim to show the utility of AUS for biomonitoring the birds’ metal exposure was not achieved because of experimental design limitations. A similar investigation was carried out into the suspected exposure of nestling seabirds to elevated metal concentrations in their fish diet. Metal concentrations in urate spheres from the seabirds were measured along with those in various body tissues of their young. This metal analysis, although limited by small sample size, provided no evidence of an elevated exposure when compared with values reported in the literature. Subsequent reanalysis of earlier tested fish samples showed normal metal concentrations, suggesting the earlier reported fish data had been incorrect. To determine if AUS can be used to measure biologically relevant levels of the avian stress hormone corticosterone, a series of experiments is described using captive great tits (Parus major). These involved the ELISA detection of excreted corticosterone in AUS extracts. The suppressive response to dexamethasone administration was measurable in AUS from these birds, suggesting a physiological validation. However many issues have still to be resolved concerning this method of measuring corticosterone levels in birds. The overall finding of this thesis is that the analysis of AUS may have potential value as a noninvasive sampling method to biomonitor environmental pollution and stress in birds.

In this thesis, I use two strategies of inquiry to further our understanding of indirect short-selling constraints. First, I interview a series of experienced market practitioners to identify their attitudes towards indirect constraints. I find little support for D’Avolio’s (2002) suggestions that short-selling is inhibited by managers’ fear of tracking error and by the cultural pressures of a society that can vilify short-sellers. However, I am able to introduce a new, social, indirect constraint to the literature – the perception that short-selling is a form of ‘trading’ as distinct from ‘investment’, and the consequent lack of acceptance amongst stakeholders that this engenders. This constraint reveals a divide between the attitudes of the academic community and parts of the institutional practitioner community on the subject of short-selling. However, interviewees argue that this indirect constraint is diminishing over time. This raises the prospect of markets in practice converging in behaviour towards the markets assumed in classical asset pricing models, and has implications for market efficiency. My second strategy of inquiry is to use a large, new stock lending database to explore three risk-related indirect constraints to short-selling. I examine ‘crowded exits’, a general class of liquidity problem, and find that these are associated with statistically and economically significant losses for short-sellers. I also examine ‘manipulative short squeezes’, a liquidity problem arising from predatory trading. Consistent with theory and the literature on the subject, I find that these are rare for larger, more liquid stocks. However, when they do occur, these events generate statistically significant losses for short-sellers. Finally, I build upon the work of Gamboa-Cavazos and Savor (2007) and investigate the response of short-sellers to losses. I find that short-sellers close their positions in response to accounting losses and not simply in response to rising share prices. This is consistent with short-sellers’ use of risk management tools that are designed to crystallize small losses. These serve to limit the risk of potentially unlimited losses and to reduce short positions at times of heightened synchronization risk. Stocks subject to shortcovering in this manner do not subsequently under-perform the market. My findings demonstrate that a sophisticated group of traders, strongly associated with price setting, does not suffer from the bias known as loss realization aversion.

This thesis investigated the application of X-ray Compton scattering to the problem of foreign body detection in food. The methods used were analytical modelling, simulation and experiment. A criterion was defined for detectability, and a model was developed for predicting the minimum time required for detection. The model was used to predict the smallest detectable cubes of air, glass, plastic and steel. Simulations and experiments were performed on voids and glass in polystyrene phantoms, water, coffee and muesli. Backscatter was used to detect bones in chicken meat. The effects of geometry and multiple scatter on contrast, signal-to-noise, and detection time were simulated. Compton scatter was compared with transmission, and the effect of inhomogeneity was modelled. Spectral shape was investigated as a means of foreign body detection. A signal-to-noise ratio of 7.4 was required for foreign body detection in food. A 0.46 cm cube of glass or a 1.19 cm cube of polystyrene were detectable in a 10 cm cube of water in one second. The minimum time to scan a whole sample varied as the 7th power of the foreign body size, and the 5th power of the sample size. Compton scatter inspection produced higher contrasts than transmission, but required longer measurement times because of the low number of photon counts. Compton scatter inspection of whole samples was very slow compared to production line speeds in the food industry. There was potential for Compton scatter in applications which did not require whole-sample scanning, such as surface inspection. There was also potential in the inspection of inhomogeneous samples. The multiple scatter fraction varied from 25% to 55% for 2 to 10 cm cubes of water, but did not have a large effect on the detection time. The spectral shape gave good contrasts and signal-to-noise ratios in the detection of chicken bones.