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Failure to manage risks often causes budget and schedule problems in software projects. Software architectures are difficult to change at later stages and determine software quality attributes such as maintainability. Error-proneness and change propagation risks occur in software that is difficult to maintain. If risks can be isolated into architecture subsets called risk containers, practitioners could prioritise mitigations towards the riskiest containers to increase the chances of project success. Some existing software architecture analysis techniques attribute maintainability risks to architecture subsets, but previous research fails to consider which kinds of architecture subsets are risk isolating (risk inducing architecture elements are not shared with other containers). Furthermore, the architecture description standard does not include guidance for describing risks. This thesis addresses those knowledge gaps. Three types of risk container are extracted from the architectural designs of four software projects and metrics are used to determine which container type is the most risk isolating. Design Rule Containers are the most effective container type because they have very strong and significant correlations between design metrics and implementation change propagation, moderate or stronger correlations between design metrics and implementation error-proneness, but crucially they overlap less than Resource and Use Case Containers which means they are more risk isolating. An experiment demonstrates that participants were able to locate more error-inducing architecture flaws using smaller container diagrams, than when using a larger overall diagram. An architecture risk model based on the international standards for architecture description and risk management is synthesised from the output architecture analysis techniques, including risk containers, so that the isolated risks can be communicated. Surveyed practitioners consider the model to be more applicable to waterfall software development than agile and prefer the model to textual risk descriptions due to the fidelity, rigour, and traceability supported by the model.

Simplistically, words are the mental bundling of a form and a referent. However, words also dynamically interact with one another in the cognitive system, and have other so-called 'lexical properties'. For example, the word 'dog' will cue recognition of 'dock' by shared phonology, and 'cat', by shared semantics. Researchers have suggested that such lexical engagement between words emerges slowly, and with sleep. However, newer research suggests that this is not the case. Herein, seven experiments investigate this claim. Fast mapping (FM), a developmental word learning procedure, has been reported to promote lexical engagement before sleep in adults. Experiment 1 altered the task parameters and failed to replicate this finding. Experiment 2 attempted a methodological replication - again, no effect was found. It is concluded that the effect reported is not easily replicable. Other findings of pre-sleep lexical engagement were then considered using a novel methodology - computer mouse tracking. Experiments 3 and 4 developed optimal mouse tracking procedures and protocols for studying lexical engagement. Experiment 5 then applied this methodology to novel word learning, and found clear evidence of immediate lexical engagement. Experiment 6 provided evidence that participants were binding the word form to the referent in these pre-sleep lexical representations. Experiment 7 sought to strengthen this finding, but has been postponed due to the CoViD-19 pandemic. The results are discussed in the context of the distributed cohort model of speech perception, a complementary learning systems account of word learning, and differing abstractionist and episodic accounts of the lexicon. It is concluded that the results may be most clearly explained by an episodic lexicon, although there is a need to develop hybrid models, factoring in consolidation and abstraction for the efficient storage of representations in the long term.

Air passenger numbers have increased steadily over the last decade and the number of wheelchair users who travel by air has grown at a faster rate. Disability is a protected characteristic under the UK Equality Act 2010. In this research, a wheelchair user was defined as someone who used a wheelchair permanently. Limited research has shown that travelling by air has been a mostly negative experience for wheelchair users and those who accompanied them, and a mixed experience for aviation staff. Most of the issues were associated with the aircraft such as the seating and accessing the toilet. This study aimed to collect the experiences and views of wheelchair users and those who accompany them, the cabin crew, and the special assistance staff who helped them at the airport. Participants were recruited through opportunistic and convenience sampling via social media and contacts with a travel adviser for disabled people. A qualitative approach using semi-structured interviews was conducted with 11 wheelchair users, 10 people who accompanied them, 11 cabin crew, and 21 special assistance staff. Template analysis and frequency counting were used to code the participant’s views. New issues were identified that included how the luggage was moved; air travel processes including parking, check-in, security, airport amenities, and how the special assistance staff move around the airport; information and communication issues; disembarkation; services on board the aircraft; staff training; and how the staff help wheelchair users. The results revealed that air travel for wheelchair users and those that accompany them was difficult and could be enhanced by improving information accuracy, optimising air travel processes including queueing and resource management, and redesigning physical aspects of the aircraft so they are fit for purpose. This research identified policies and procedures that the aviation industry could adopt when helping wheelchair users who fly.

Faults may impact subsurface fluid flow over production and geological timescales. Predicting fault permeability is crucial for understanding subsurface fluid flow, which is required for a number of subsurface industries. Fault permeability is determined by the micro-fabric and distribution of fault rocks, which are influenced by the deformation mechanisms exhibited during faulting, fault-related diagenesis, and fault zone architectural evolution. Non-uniform strain distributions along fault zones lead to heterogeneous fault cores, therefore, predicting fault permeability is difficult. Empirical relationships linking lithological parameters to the petrophysical properties of different fault rocks are commonly utilised to predict fault permeability in clay-bearing sequences. However, no such relationships exist for carbonate rocks. A better understanding of these controls, in addition to the characterisation of fault rock permeability is required to establish predictive relationships for fault rock permeability. This thesis combines structural, microstructural and petrophysical data from a series of carbonate-hosted fault zones in Malta. Thereby enabling an understanding of the fault zone permeability structures in various lithofacies, whilst highlighting the heterogeneity on all scales of carbonate-hosted fault zones. The continuity of fault rock is shown to increase with displacement, and displacement thresholds for both a continuous fault core and cataclasite are established for fault zones in Malta. Only fault rocks derived from high porosity host rocks have the potential to retard fluid flow over reservoir scales. Lithological heterogeneity is retained within fault cores, whereby the heterogeneity of the faulted lithofacies is linked to the variability in fault rock petrophysical properties. Novel methods of upscaling fault permeability and implementing fault rock continuity relationships to fault property modelling are presented. The results provide an example of how porosity of the host carbonate can impact fault rock permeability under low stresses. Combined with similar studies from different lithofacies and structural settings, this thesis contributes towards a generalised understanding of the controls on fault permeability in porous carbonate rocks.

End stage liver disease represents a common end point for a number of disease processes, the only current treatment for which is liver transplantation, but the demand for donor organs exceeds the supply. This has led to the use of more marginal donors with an increase in the rates of complications. Mesenchymal stem/stromal cells (MSC) are a multipotent cell capable of modulating the immune system through a number of different processes and represent a potential therapy in post transplantation liver injury. In this study I describe the prospective isolation and culture expansion of murine MSC. In in vitro assays MSC suppressed T lymphocytes and following stimulus with inflammatory cytokines MSC secreted a number of cytokines including Il-10. In the MDR2-/- model intravenous MSC therapy led to a reduction in liver injury with an increase in restorative macrophages. Subcutaneous administration of MSC showed no beneficial effect. MSC were also tested in a hepatic ischaemia reperfusion injury model where no effect was seen. In summary MSC were able to suppress lymphocyte proliferation and secrete anti-inflammatory cytokines in vitro, and in vivo they were able to reduce liver injury in the MDR2-/- model but not the hepatic ischaemia reperfusion injury mode.

Automatic music transcription (AMT) is commonly defined as the process of converting an acoustic musical signal into some form of musical notation, and can be split into two separate phases: (1) multi-pitch detection, the conversion of an audio signal into a time-frequency representation similar to a MIDI file; and (2) converting from this time-frequency representation into a musical score. A substantial amount of AMT research in recent years has concentrated on multi-pitch detection, and yet, in the case of the transcription of polyphonic music, there has been little progress. There are many potential reasons for this slow progress, but this thesis concentrates on the (lack of) use of music language models during the transcription process. In particular, a music language model would impart to a transcription system the background knowledge of music theory upon which a human transcriber relies. In the related field of automatic speech recognition, it has been shown that the use of a language model drawn from the field of natural language processing (NLP) is an essential component of a system for transcribing spoken word into text, and there is no reason to believe that music should be any different. This thesis will show that a music language model inspired by NLP techniques can be used successfully for transcription. In fact, this thesis will create the blueprint for such a music language model. We begin with a brief overview of existing multi-pitch detection systems, in particular noting four key properties which any music language model should have to be useful for integration into a joint system for AMT: it should (1) be probabilistic, (2) not use any data a priori, (3) be able to run on live performance data, and (4) be incremental. We then investigate voice separation, creating a model which achieves state-of-the-art performance on the task, and show that, used as a simple music language model, it improves multi-pitch detection performance significantly. This is followed by an investigation of metrical detection and alignment, where we introduce a grammar crafted for the task which, combined with a beat-tracking model, achieves state-of-the-art results on metrical alignment. This system's success adds more evidence to the long-existing hypothesis that music and language consist of extremely similar structures. We end by investigating the joint analysis of music, in particular showing that a combination of our two models running jointly outperforms each running independently. We also introduce a new joint, automatic, quantitative metric for the complete transcription of an audio recording into an annotated musical score, something which the field currently lacks.

This thesis poses a simple but intriguing and powerful question. Can Pope Leo IX (1049-1054) continue to be described as a reforming or reform-minded pope? The approach taken rethinks Leo and rethinks reform and the analysis of each, taken together, leads to a fresh evaluation of what Leo did and how he went about it. This thesis focusses on his pontificate and is not a full life biographical portrait. The historiographical background of the last one hundred and thirty years is comprehensively analysed. This analysis shows that the descriptor of reform has been applied to Leo consistently over that period but that only one attempt has been made to define reform. This thesis puts forward a new definition of reform which is used to provide a framework for evaluation and for clarifying the answer to the thesis question. Leo’s extant papal letters and other sources provide the basis for a new and full analysis of what Leo actually did in his Synods. This analysis shows that Leo used his Synods for complex and multi-faceted purposes. These purposes were not so much to push a reform agenda but more to resolve disputes, to deal with simony and to deal with very many issues related to Church governance. Leo’s letters are also used to analyse afresh the reasons for his many journeys. The analysis shows that Leo’s journeys were undertaken for multiple reasons and were not specifically related to the long standing view that the journeys relate to Leo’s attempt to Europeanise the papacy. Finally the letters are utilised to ask questions of Leo’s overall policy approach to papal governance. This analysis puts forward new ideas about the team in the papal office and reveals a complex landscape of influences. Taken together these strands of analysis show a complex picture and highlight a new perception of Leo and that the long held premise of seeing Leo through the single prism of reform confuses and obscures the real nature of his policy approach and his pontificate. The conclusion of this thesis is that Leo can no longer be accurately described as a reforming pope but rather as an important one who was both a conservative and traditionalist. The implications of this for the grand narrative of the history of eleventh century Europe are considerable. The roles of the other principal actors need to be thought out afresh; the notion of reform itself needs to be reconsidered and the antecedents of the so-called Gregorian reform fall to be re-evaluated.

Solar flares are one mechanism to release stored magnetic energy in the Sun’s atmosphere. This thesis aims to determine whether sunspot rotation can inject the energy required for solar flares into the corona. This thesis investigates the relationship between sunspot rotation and solar flares, and the impact that sunspot rotation has on the strength and frequency of flare events. A robust analysis tool is developed which uses continuum images of the Sun to determine the rotation of sunspots. This tool is used throughout the thesis, first on the active region 11158, in an in-depth case study of the rotation and flaring properties of the region as it traverses the solar disc. The case study develops analysis techniques, such as introducing sunspot selection criteria, which are used in the following statistical studies. The first statistical study involves the analysis of the rotation and flaring properties of a sample of all sunspots that meet the selection criteria within all X-class flaring regions since the launch of the Solar Dynamics Observatory. As this first statistical study is biased towards higher flare-energy active regions, a second unbiased statistical study is carried out on all sunspots that meet the sunspot selection criteria between 1 May 2013 and 31 August 2013. The results of these statistical studies are combined and analysed, concluding that sunspot rotation injects enough energy (and in the majority of cases, an excess of energy) to account for the energy output by solar flare radiation. On average, the radiated bolometric flare energy outputs 65.6% of the injected energy due to the absolute sunspot rotation for the X-class flare sample, and 59.2% for the four-month sample.

The late twentieth and early twenty first centuries have seen developments within atonement theology that seek to promote nonviolence by removing the cross of Christ as the central work of Christ, producing what has become known as “nonviolent atonement theology.” Previous research has critiqued these developments by assessing them individually and using hermeneutical, historical and theological criteria. However, it will be argued in this study that nonviolent theology is motived by an ethical concern for the Other, a grouping which will be defined as those outside positions of power and at risk of oppression. The nonviolent atonement theology of literary critic and anthropologist Rene Girard, feminist theologians Rosemary Radford Ruether, Mary Grey and Rita Brock and Ann Parker, and Anabaptist thinker J. Denney Weaver are critically discussed, showing how this concern for the Other has led to political understandings of the doctrines of sin, the work of Christ and salvation. Having assessed these developments the thesis argues that nonviolent atonement theology has a potentially negative impact upon the Other, while providing an alternativecruciform model in the work of P.T. Forsyth. It is the contention of this thesis that Forsyth’scruciform theology offers a plausible alternative to nonviolent atonement theology due to the interweaving of kenotic and sociopolitical themes within a form of atonement theology that remains substitutionary.

Regular assessment of the state and change of the world’s forests is essential because of the range of climate and ecosystem services they provide. Earth observation efforts responsible for monitoring the above-ground biomass (AGB) of the world’s forests, a frequently used proxy for forest state, rely on calibration from a network of field plots. In lieu of impracticable direct measurement of AGB at these plots, estimates are ob- tained through empirical allometric correlations that relate simple measurements of tree structure, to mass. Throughout tropical forest, few pan-tropical allometric models exist because of the limited availability of calibration data. In this thesis, the best available pan-tropical allometric dataset is used to demonstrate that the statistical method employed in the construction of all widely used models, log-transformed ordinary least squares linear regression, is inappropriate. Alternatively, a new non-linear model is proposed where uncertainties are derived from non-parametric methods. These uncertainties are shown to exceed 75 % and 25 % of AGB at the tree- and plot-scale respectively. This leads to the conclusion that AGB estimates of large swathes of tropical forest are statistically indistinguishable from one another when inferred through pan-tropical allometry. These results highlight the need to introduce alternative methods. The primary objective of this thesis is to demonstrate that new 3D measurements of forest structure from terrestrial laser scanning (TLS) can provide accurate non-destructive estimates of AGB. Rich point clouds have been acquired across multiple forest types. Novel algorithms are developed and applied here to retrieve tree-scale AGB via volume estimation on a wide-scale. It is shown these new methods can estimate tree- and plot-scale AGB to within 23.3% and 7.9% of the respective direct measurement. It is shown these TLS-derived estimates of AGB, are, on average, 17.9 % larger than their allometric-derived counterparts. Allometric methods may thus significantly underestimate tropical forest carbon stocks.

Pressure filtration is one of the most common solid-liquid separation techniques in use in the fine chemical and pharmaceutical industry. Typically pressure filtrations are conducted within the same unit operation as agitated drying, thus the opportunity to study the individual effects of filtration are often negated. Recent findings have shown pressure filtration to be a major cause of particle breakage, which has consequences for product quality, bioavailability and downstream operations like formulation. A new method for the investigation of the effect of hydrodynamic stress on static crystals has been developed by continuously recirculating fluid through a bed of freshly crystallised particles. The method is compared to traditional batch pressure filtration tests with good correlation between results. Levels of breakage of needle-like glutamic acid crystals are found to increase with rises in pressure and fluid flow rate. Particle size and shape data obtained from optical microscopy is critically analysed in order to determine the type and extent of crystal breakage. Automated methods have also been developed to filter particle data in order to provide a more representative measurement. Small-scale centrifugal testing of particle beds has been conducted with an analytical photo-centrifuge. Needle-like crystal beds are found to consolidate to greater extents than more rounded particles, and also show evidence of inelastic behaviour. The more isometric particles conversely display elastic behaviour in response to the application of stress. Modelling of particle data has simulated algorithmic breakage events to predict the breakage observed under pressure filtration, with good agreement between modelled and experimental particle size distributions. The structure of particle beds has also been modelled by generation of simulated needle-beds from particle length data.

The generation of three-dimensional (3D) building models without roof geometry is currently easily automated using a building footprint and single height value. The automatic reconstruction of roof structures, however, remains challenging because of the complexity and variability in building geometry. Attempts from imagery have utilised high spatial resolution but have only reconstructed simple geometry. This research addresses the complexity of roof geometry reconstruction by developing an approach, which focuses on the extraction of corners to reconstruct 3D buildings as boundary representation models, to try overcome the limitations of planar fitting procedures, which are currently favoured. Roof geometry information was extracted from surface models, true orthophotos and photogrammetric point clouds; reconstructed at the same spatial resolution of the captured aerial imagery, with developments in pixel-to-pixel matching. Edges of roof planes were extracted by the Canny edge detector, and then refined with a workflow based on the principles of scan-line segmentation to remove false positive detection. Line tracing procedures defined the corner positions of the extracted edges. A connectivity ruleset was developed, which searches around the endpoints of unconnected lines, testing for potential connecting corners. All unconnected lines were then removed reconstruct 3D models as a closed network of connecting roof corners. Building models have been reconstructed both as block models and also with roof structures. The methodology was tested on data of Newcastle upon Tyne, United Kingdom, with results showing corner extraction success at 75% and to within a planimetric accuracy of ±0.5 m. The methodology was then tested on data of Vaihingen, Germany, which forms part of the ISPRS 3D reconstruction benchmark. This allowed direct comparisons to be made with other methods. The results from both study areas showed similar planimetric accuracy of extracted corners. However, both sites were not as successful in the reconstruction of roof planes.

The British Army’s regular Mounted Infantry was arguably one of the most important innovations of the late Victorian and Edwardian armies. This thesis explores the regular Mounted Infantry model from its origins in extemporised infantry detachments overseas to its formal organisation as non-cavalry mounted troops before the First World War and juxtaposes its organisation and changing roles with its fractious relationship with the cavalry. Using four campaigns as case studies, the thesis provides a comparative assessment of the Mounted Infantry’s military effectiveness that culminated in it becoming the successful archetype for the British soldier in South Africa in the years 1901- 02. The Mounted Infantry’s uniqueness compared to other nations’ armies is considered and the thesis identifies how other armies satisfied the requirement for mobile firepower. The Mounted Infantry was abolished in 1913 prior to the First World War. The reasons influencing this decision are analysed and indicate that the Mounted Infantry’s abolition owed more to politics than lack of military utility. The thesis concludes that rather than an impecunious alternative to an inadequate cavalry, the Mounted Infantry paradigm satisfied a particular need borne out of colonial campaigning.

Research investigating the role of two evolutionary constructs – perceptions of defeat and entrapment – in various psychological problems and processes has burgeoned over recent years. This meta-analysis quantitatively summarised the findings from 38 studies (11,343 participants) which examined relationships between perceptions of defeat and entrapment and four psychological problems commonly encountered in NHS clinical services: depression, suicidality, anxiety problems and Post-Traumatic Stress Disorder (PTSD). All correlations between defeat and entrapment and the four psychological problems were large by Cohen’s (1988) criterion. Correlations between defeat and entrapment and depression were larger than those for the other psychological problem groups, and significantly larger than those for anxiety problems and PTSD. The magnitude of the observed correlations introduces the possibility that defeat and entrapment, and perhaps other evolutionary constructs, may be integral components or driving forces behind all psychological problems. A robust approach to sensitivity analysis provided confidence that the population effect size estimates are robust and were not severely inflated by unpublished studies not included in the meta-analysis. As there was no significant between-study heterogeneity, moderator analyses were undertaken on an exploratory basis. Findings are generally consistent with theoretical predictions from the Involuntary Defeat Strategy, the theoretical model underpinning the literature. Overall, perceptions of defeat and entrapment appear to be strong risk factors for the four psychological problems examined, perhaps representing transdiagnostic processes that are common across various psychological problems. The potential role of defeat and entrapment in mental health assessment, formulation, intervention and evaluation, is considered in detail and limitations of this meta-analysis and of the literature on which it is based are discussed, highlighting areas of research where future work is needed.

The mammalian carotid body (CB) is the primary sensory organ that responds to a reduction in arterial O\(_2\) tension. Activation of the CB and stimulation of its chemoafferent fibres evokes a series of well characterised cardiovascular and respiratory reflexes that act to restore normal O\(_2\) levels throughout the organism. A role for an elevated CB chemoafferent outflow in the aetiology and progression of a number of cardiorespiratory disease states has been identified, underlying the importance of understanding the signalling mechanisms required to activate the CB in hypoxia. In this thesis evidence is provided indicating that the CB response to hypoxia is a consequence of a reduction in mitochondrial energy metabolism and stimulation of the liver kinase B 1/AMP activated protein kinase signalling cascade. Questions also remain over the potential for other stimuli to acutely stimulate the CB. Observations described in this investigation suggest that the CB is not directly sensitive to glucose deprivation and that it preserves energy status in these conditions by metabolism of stored glycogen. Finally, chemoafferent outflow is, ultimately, dependent upon neurotransmission and small molecule neuromodulation. This thesis demonstrates a previously uncharacterised key functional role for adenosine derived from extracellular catabolism of ATP in mediating chemoafferent activity.