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Trust is the foundation of trade credit. Failure to pay on time affects the supplier's business, causing stress and potential bankruptcy. Small businesses employ formal (solicitors, debt collectors, statutory demands) and informal (discounts, extended payment terms, violence) techniques to enforce payment. The Government has enacted measures requiring larger buyers to report their payment practices and has given businesses the right to claim interest, yet businesses are either unaware or do not use these provisions. The research phase of this thesis was conducted in 2018/19 and incorporated an initial survey with 74 respondents followed by a second survey with 250 respondents. During the period, 20 in-depth interviews were undertaken to gain a deeper insight into specific points. This research finds that small businesses do not conduct sufficient due diligence, selling to anyone and hoping buyers will pay while relying on law to ensure payment. The effects of late payment resulted in 81% of respondents saying they had experienced increased stress which permeated outside the workplace. Furthermore, the findings revealed that at the micro and small business level respondents considered the emotional effect of late payment to be greater than the monetary impact on the business. Large businesses reported the temporal effect to be of greater concern than the monetary impact. Faced with a late payment, 44% of respondents considered escalating collection processes, and a third commenced litigation. Interviewees considered the current legal system expensive and unworkable. Litigation was however used as a method of restoring communication with a defaulting buyer to obtain (partial) settlement as opposed to gaining judgement and restitution. This thesis widens the debate on late payment from a purely quantitative monetary business problem to incorporate the qualitative impact on human assets.

The environments in which athletes develop and perform can have a significant impact upon performance outcomes. Previous research has predominantly focused on the psychological performance environment of athletes within, and leading up to, competitive performance events. There has been little consideration given to psychological factors in the practice environment that might influence both development and performance. As a result, the focus of this programme of research was to explore the psychological factors influencing athlete development and performance in the practice environment. To achieve this purpose five studies were completed within UK academy basketball practice environments. Using qualitative research methods that could offer rich perceptual data, the first and second studies provided an initial exploration of the psychological influencing factors in the practice environment to create a conceptual framework using interpretative phenomenological analysis and case study respectively. Study three applied the practice environment framework longitudinally within a larger UK basketball academy participant population. Study three findings suggested that the framework existed within the multiple practice environments investigated. Study four used an interpretative phenomenological analysis approach to provide a rich and deep gathering of basketball coach perception. Coach perceptual data offered both confirmation and deeper insights into influencing factors, with additions being made to the practice environment framework. Five key practice environment factors developed from the previous exploratory studies, which were high effort being a player’s primary goal in the practice environment, players undertaking pre-practice performance reflection, players developing supportive communication, the setting of common goals to enhance team performance, and an enhanced preparation period before practice, were applied as an educational strategy in study five to improve performance within a real-world basketball practice environment. The factors of influence were found to be complex, related, and highly dependent upon specific practice environment scenarios. The overall findings from the current programme of research suggest the psychological influencing factors of the practice environment are different to other sporting environments that athletes experience. In particular, effort and control, individual and team orientations, communication and negative motivation, performance expectations and social interactions, preparation, and player and coach characteristics, were highlighted as specific to the influencing factors of the practice environment. Therefore, practice could be considered as a standalone environment within the performance environments of athletes. The framework produced in the current programme of research is based on a UK academy basketball environment and could be of use to practitioners within that setting to enhance athlete development and performance in the practice environment.

The upcoming Dark Energy Spectroscopic Instrument (DESI) and Euclid galaxy surveys aim to make the most precise galaxy clustering measurements yet in order to probe the nature of the mysterious dark energy that is thought to make up the majority of the energy density of the Universe today. To reach the required precision, it is essential that the systematics that affect these measurements are understood, which requires realistic mock galaxy catalogues. This thesis focuses on building a mock catalogue for the DESI Bright Galaxy Survey (BGS), and applications of this mock. We outline the methods used to create halo merger trees from N-body and Monte Carlo simulations, which is the first step towards creating a mock catalogue. We show how these methods can be extended beyond ΛCDM to warm dark matter, and show applications. We have developed a halo occupation distribution (HOD) method for creating a BGS mock catalogue from the Millennium-XXL (MXXL) simulation, with galaxies being assigned r-band magnitudes and g-r colours. The mock catalogue is able to reproduce the luminosity function and clustering of the Sloan Digital Sky Survey (SDSS) and Galaxy And Mass Assembly (GAMA) survey at different redshifts. The mock is used to quantify incompleteness in the DESI BGS due to fibre assignment, which depends on the surface density of galaxies, and to assess correlation function correction methods. An inverse pair weighting method is able to provide an unbiased correction on all scales. Finally, we show how the HOD methodology can be extended to construct mock catalogues for Euclid, and other large galaxy surveys.

Hydrothermal carbonisation (HTC) is an emerging biomass pre-treatment that works by converting biomass into a coal like material, in the process overcoming some of the inherent limitations of biomass. To date, there have been limited publications looking into the fate and influence inorganics and heteroatoms have on the HTC chemistry. This is surprising given these elements are of critical importance when it comes to the fuel’s utilisation. This work sets out to understand the role and fate of key inorganics and heteroatoms during HTC, but goes on to develop a mechanistic understanding of the HTC process chemistry. This work primarily focuses on the feedstocks Miscanthus, willow, brown kelp (macroalgae) and swine manure. Additionally, this work has also looked into the processing of food waste, secondary sewage sludge, AD press cake, microalgae, municipal solid wastes and oak wood, providing a large database of samples. Reaction parameters investigated as part of this work include how temperature, retention time, particle size, pH and recycling of process waters influence product yields, energy density, combustion properties, the bio-chemical composition of the bio-coal, the process water chemistry and the retention and removal of inorganics and heteroatoms. The results show that under the correct conditions HTC can produce a fuel with a HHV ranging from 25 to 30 MJ/kg (db) and the resulting bio-coal can burn like a coal, grind like coal and can overcome many of the limitations of burning biomass in pulverised coal plant. By recycling the process waters Miscanthus can be made into a fuel with an energy density of 29 MJ/kg (db), with an energy yield of 91 % and fuel properties comparable to a high volatile sub-bituminous coal. The behaviour of the inorganics and heteroatoms during HTC appear dependent on feedstock, the feedstocks inorganic chemistry and the HTC processing conditions. Generally speaking, alkali metals, which are primarily responsible for the slagging and fouling behaviour of solid fuels, are largely removed (>80%) during HTC. Moreover, when processing at 250 °C retention of calcium and reincorporation of phosphorus occurs. The combination of reduced alkali metals and relative increase in calcium and phosphorous in the ash brings about significant improvement in the fuels slagging and fouling propensity as demonstrated by the ash fusion test. It hypothesised that any residual potassium within the fuel should form calcium potassium phosphate complexes in the ash. These complexes are thermally stable and prevents the formation of low melting temperature potassium silicates or the volatilisation of potassium chloride, further reducing slagging, fouling and corrosion beyond that expected for alkali metal leaching. This can be applied to a range of low value fuels such as green harvested Miscanthus and seaweeds. This demonstrates the technologies potential to valorise low quality feedstock and produce a direct substitute bio-coal from an expanded range of terrestrial and aquatic biomass. Recycling process water brings about an increase in bio-coal energy density, energy yield and produces a fuel with more coal-like properties. It is hypothesised that the recycled process waters contain organic acids that hydrolyse the hemicellulose and cellulose to furfural like compounds at a lower temperature and increase saccharide concentrations within the process water at lower temperatures. The increased saccharide concentrations favour aromatization and repolymerisation, which better enables the decomposition products to undergo polymerisation and form the bio-coal before the increasing process temperature brings about their further degradation to organic acids. Once degraded to organic acids these acids appear to only undergo limited reincorporation into the bio-coal, but do appear to play a role in the demineralisation of the fuel. Based on this it is proposed that the slow heating rates followed by an hour retention time is favourable to overcome kinetic limitations otherwise imposed by faster heating rates and shorter retention times. The heteroatom oxygen plays a critical role in the reactions involved in HTC. The energy densification of the bio-coal is largely due to the deoxygenation of the fuel. Removal of this oxygen forms unsaturated compounds that polymerise quickly, and intermolecular dehydration results in polymerisation, condensation and aromatisation of these fragments. Oxygen is also critical in repolymerisation, with aromatic structures initially chemisorbed though reactive oxygen functionalities that dehydrate to form stable oxygen bonds linking a polymeric matrix of cyclic aromatic carbon rings. The retention of calcium also suggests it may play catalytic role in the repolymerisation process with the literature supporting this. There is however evidence that at high calcium concentrations, calcium in the process water can have an adverse effect on carbonisation, binding to surface oxygen functional groups on the biomass feedstock and preventing hydrolysis and decomposition of the feedstock.

Locusts undergo dramatic changes in behaviour, morphology and physiology in response to changing population densities, leading to the formation of devastating swarms. Of these forms of phenotypic plasticity, known collectively as phase polyphenism, behavioural plasticity is the most rapid. Shy, cryptic solitarious phase locusts can change their behaviour within 4 h of exposure to conspecifics to resemble that of locusts in the active, swarming gregarious phase (“gregarise”). In this thesis, I use a multidisciplinary approach to investigate the neurochemical mechanisms underpinning behavioural phase polyphenism in the locust. In Chapters 3 and 4, my investigations using an established behavioural assay, High-Performance Liquid Chromatography and pharmacology found no evidence supporting published claims that the neuromodulator 5-hydroxytryptamine in the thoracic ganglia is required for gregarisation. My work indicates a need for further re-investigation of the roles of monoamines in locust phase polyphenism. In Chapter 5, I ran locusts through repeated behavioural assays to reproduce an unexpected phase-specific behavioural change observed in Chapter 4, a potentially novel phase-specific familiarity response to repeated behavioural observations. Solitarious locusts increased their exploratory activity after repeated observations at 2 h intervals, but this effect was not present for longer intervals nor in a different paradigm. I suggest methodological refinements to examine the origins of this potential phase-specific familiarity response. In Chapter 6, I used an assembled transcriptome to identify locust orthologues of four immediate-early genes widely used to create neuronal “activity maps” in other species, in an attempt to apply this to S. gregaria during gregarisation. Quantitative Polymerase Chain Reaction analyses found no activity-related changes in transcription of these genes in solitarious locusts crowded for 30 min compared with uncrowded controls. My work suggests no involvement of these genes in the early stages of gregarisation. This paves the way for optimisation of this novel tool in the locust.

In terms of studies of British imperialism, the Royal Navy, and more particularly its sailors during the late-nineteenth and early-twentieth centuries, has remained a neglected topic. Historical studies of the navy continue to be dominated by naval historians, who are primarily concerned with the technical and strategic aspects of the Royal Navy. In the past 10 years there has been a gradual intrusion upon this and a number of socio-cultural and gender historians have turned their attention in this direction. Therefore, this thesis continues this development and examines the relationship that the lower deck had with imperialism by examining the testimony of sailors through unpublished diaries held in museum collections. It charts the period chronologically and thematically through events of naval pageantry and war, which reveals the complexities of the sailor’s character particularly around the concepts of imperialism, identity, pride and patriotism. By examining sailors as they experienced imperialism through both peace and war, it reveals that the Empire was a vital aspect of their lives and also their own identity. As a significant part of the imperial construct within British culture, sailors consequently viewed their experiences through an imperialistic prism. However, it reveals that sailors were not simply passive recipients of imperial inculcation and demonstrated a level of independence to this. Thus it is argued that their relationship with imperialism was part of a wider independent sailor culture, which competed with individual beliefs, differing loyalties, and could mean different things at different times.

This thesis seeks to explore if there is a defining philosophy, theory and methodology underpinning problem structuring methods (PSMs). PSMs are a class of qualitative Operational Research (OR) approach for making progress with ill-structured problems. The development of each of the established approaches was in relative isolation with little research cutting across all PSMs. There are no agreed standards or characteristics for an approach to be considered a PSM. This creates a problem for the increasing number of newly developed qualitative OR approaches which share many common features with the established PSMs but are not recognised as such. To close this gap the thesis conducts analysis of the literature identifying these common features. To understand the diversity of theory and methodology of PSMs this thesis theoretically and methodologically develops the existing qualitative OR approach WASAN and positions it alongside the existing PSMs. Bridging the gap between established PSMs and other qualitative approaches will identify the qualifying features of PSMs, how to identify these features in other approaches and how theory development in one approach can be transferred to other PSMs. Next the thesis develops the qualitative OR approach WASAN through an action research program. The problem context is a UK Police Force who are aiming to reduce wasted time in their emergency contact centre. The researcher modelled four individual systems in customer contact using WASAN. WASAN considers how behaviour of an upstream system can increase waste production in the system being modelled. The research analysed the individual models and the interaction between models. The research project shows how to identify the features of PSMs in an approach; the process of developing a bespoke approach into a generic approach; and, the commonality of an underpinning framework between WASAN and the existing PSMs through the transferability of theoretical contributions.

T2K is a long baseline neutrino oscillation experiment which uses a beam of muon neutrinos to study muon neutrino disappearance and electron neutrino appearance. The measurement of v_e appearance is sensitive to CP violation, and reducing the systematic uncertainties is critical to enabling experimental determination of whether there is CP violation in the lepton sector. This thesis describes the first measurement of the v_e CC inclusive cross-section on carbon at energies relevant to T2K and other long baseline neutrino oscillation experiments. The T2K near detector, ND280, is used to select a sample of v_e events, and a Bayesian unfolding technique is used to extract differential cross-sections as a function of electron momentum, electron angle and Q^2. The total flux-averaged cross-section is also extracted, and is found to be 1.11 ± 0.20 x 10^{-38} cm^2/nucleon, which agrees well with both the NEUT neutrino interaction generator prediction of 1.23 x 10^{-38} cm^2/nucleon and the GENIE prediction of 1.08 x 10^{-38} cm^2/nucleon. A restricted phase-space analysis is also performed, in which only events where the ejected electron has momentum greater than 550 MeV/c and cos(θ_e) > 0.72 are selected. In this case, the flux-averaged cross-section is found to be 6.54 ± 1.22 x 10^{-39} cm^2/nucleon, again in good agreement with both the NEUT prediction of 7.38 x 10^{-39} cm^2/nucleon and the GENIE prediction of 6.41 x 10^{-39} cm^2/nucleon.

The purpose of the research reported in this thesis was to investigate the viability and quantify the potential gains of improving fuel economy of the gasoline engine through strategic application of additives. An increased awareness of the link between greenhouse gas emissions and global warming means that there is a desire to reduce carbon dioxide emissions from transportation. There is therefore a growing emphasis on improving the fuel economy performance of vehicles. The addition of friction modifier additives to the fuel is one way to achieve this. Using bespoke in-cylinder sampling techniques, an understanding of the operation of the piston assembly, a system responsible for much of the power loss in the internal combustion engine, is developed. Validation is given to the hypothesis that fuel economy gains can be achieved through the application of friction modifier administered to the engine via the gasoline. Results show gasoline administered friction modifier additive can accumulate in the piston assembly lubricant at levels 77 times greater than the initial fuel treatment level. The performance of a large number of friction modifier additives were uniquely screened in a novel bench-top test which simulated the arduous in-cylinder conditions found in a firing gasoline engine. The test generated vast amounts of information which led to high performance formulations capable of reducing the friction coefficient in both the boundary and mixed lubrication regimes by around 50% when compared with the result for the base oil alone. Surface analysis techniques were also employed 0!l engineering surfaces coated with friction modifier additives and add to the knowledge of their mechanism of action. Finally a series of engine tests were conducted which prove the effectiveness of friction modifier administered to the engine via the gasoline. A fuel economy improvement of approximately 2% was seen where friction modifier gasoline was employed. Application of successful technology such as this is shown to correspond to the projected saving of around 502 million litres of gasoline and 388,000 tonnes of carbon (C02) per year in the UK alone.

If G is a group acting on a set Ω, and α, β ∈ Ω, the directed graph whose vertex set is Ω and whose edge set is the orbit (α, β)G is called an orbital graph of G. These graphs have many uses in permutation group theory. A graph Γ is said to be primitive if its automorphism group acts primitively on its vertex set, and is said to have connectivity one if there is a vertex α such that the graph Γ\{α} is not connected. A half-line in Γ is a one-way infinite path in Γ. The ends of a locally finite graph Γ are equivalence classes on the set of half-lines: two half-lines lie in the same end if there exist infinitely many disjoint paths between them. A complete characterisation of the primitive undirected graphs with connectivity one is already known. We give a complete characterisation in the directed case. This enables us to show that if G is a primitive permutation group with a locally finite orbital graph with more than one end, then G has a connectivity-one orbital graph Γ, and that this graph is essentially unique. Through the application of this result we are able to determine both the structure of G, and its action on the end space of Γ. If α ∈ Ω, the orbits of the stabiliser Gα are called the α-suborbits of G. The size of an α-suborbit is called a subdegree. If all subdegrees of an infinite primitive group G are finite, Adeleke and Neumann claim one may enumerate them in a non-decreasing sequence (mr). They conjecture that the growth of the sequence (mr) is extremal when G acts distance transitively on a locally finite graph; that is, for all natural numbers m the stabiliser in G of any vertex α permutes the vertices lying at distance m from α transitively. They also conjecture that for any primitive group G possessing a finite self-paired suborbit of size m there might exist a number c which perhaps depends upon G, perhaps only on m, such that mr ≤ c(m-2)r-1. We show their questions are poorly posed, as there exist primitive groups possessing at least two distinct subdegrees, each occurring infinitely often. The subdegrees of such groups cannot be enumerated as claimed. We give a revised definition of subdegree enumeration and growth, and show that under these new definitions their conjecture is true for groups exhibiting exponential subdegree growth above a prescribed bound.

A total of 450 isolates of Staphylococcus aureus were typed using multilocus sequence typing (MLST). They were isolated from the cattle and environment of a UK organic dairy farm, 43 dairy herds in the USA, the mammary glands of cattle in Chile and the UK, and also included the reference strain Newbould 305 (NCIMB 702892). Strains were compared to investigate differences between isolates from varying sites of isolation and the population detected on a single farm. MLST was suitable for the differentiation of bovine associated S. aureus, and thirty different sequence types were detected. These contained a number of novel alleles detected at each loci, agreeing with previous reports of host-specialisation, and indicating localised strain evolution. MLST was also able to discriminate between isolates detected in milk and on teat skin. The N ewbould 305 strain was significantly (p<0.05) associated with teat skin, and this may have important implications for future studies. The majority of isolates (87.4%) were present within one previously undescribed clonal complex (CC97), which contained representatives from all three geographic locations. Analysis of isolates from a single farrri demonstrated the clonality of the organism, supporting the theory of cow-to-cow spread of disease. No isolates were detected in heifer mammary secretions, suggesting transmission to these animals did not occur. Typing of multiple colonies from a single sample demonstrated strain heterogeneity within individual quarters. Environmental isolates were detected, though it is unlikely that they formed a significant reservoir of infection on the farm studied.

Windbreaks have been promoted as a means of arresting degradation of agricultural lands in the Sahel resulting from deforestation, but competition for water between windbreak trees and adjacent crops must be minimised if windbreaks are to be successfully established in areas where crop production is threatened by loss of trees. Research was done, consequently, between 1991 and 1993 in southern Niger, in West Africa, to aid development of strategies for the deployment of windbreaks in the Sahel which minimise competition for water. The objectives of this research were to: (1) quantify water use by windbreak trees; (2) determine the source of water utilised by windbreaks; and (3) identify the environmental and physiological variables controlling transpiration by windbreak trees. The heat-pulse method was used to measure water use during the cropping season by three tree species growing in windbreaks and patterns of water extraction from soil adjacent to windbreaks of each species were assessed from soil moisture contents measured by neutron attenuation. Azadirachta indica transpired less water than either Acacia holosericea or Acacia nilotica and extracted less water from the rooting zone of nearby crops, and was thus shown to be the least competitive of these tree species. Naturally-occurring variations in the ratio of the stable isotopes of oxygen (¹⁸O/¹⁶O) in water were utilised to trace the sources of water transpired by Azadirachta indica trees in windbreaks and adjacent crops of pearl millet (Pennisetum glaucum) at two locations with contrasting water table levels. Where groundwater could be accessed by the trees, they obtained large proportions of their water from surface layers of the soil only when water there was plentiful, for example after rain. Where groundwater was not accessible, the trees fulfilled their requirements for water from the surface layers of the soil profile throughout the year. Thus, competition for water between windbreaks and crops is more severe at locations where trees cannot utilise groundwater.

Sepsis is a complication caused by the overwhelming and life-threatening response of the body to an infection. Sepsis can lead to tissue damage, organ failure, and death (Center for Disease Control and Prevention, 2016). Sepsis is the leading cause of death in U.S. hospitals. Mortality from sepsis increases 8% for every hour that treatment is delayed. Each year, 258,000 people die from sepsis in the U.S. As many as 80% of sepsis deaths could be prevented with rapid diagnosis and treatment (Sepsis Alliance, 2016). This project seeks to improve the ability of the transfer unit to screen patients, improve early recognition and evaluation of best practices, and provide a connection with a provider for care consultation. This potential significance of this project is to improve patient outcomes including mortality, length of stay, and the assignment of patients to the appropriate level of care through early recognition of sepsis and the implementation of best practices. The use of a screening process to identify abnormal patient variables including elevated serum lactate, decreased blood pressure, elevated respiratory rate, and altered mental status can identify an increased likelihood of sepsis.

UK Biobank is a large-scale prospective epidemiological study with all data accessible to researchers worldwide. It is currently in the process of bringing back 100,000 of the original participants for brain, heart and body MRI, carotid ultrasound and low-dose bone/fat x-ray. The brain imaging component covers six modalities (T1, T2 FLAIR, susceptibility-weighted MRI, Resting fMRI, Task fMRI and Diffusion MRI). Raw and processed data from the first ∼42,000 imaged subjects has recently been released for general research access. To help convert this data into useful summary information, we have developed an automated processing and QC (Quality Control) pipeline that is available for use by other researchers. In this work, we describe the tools and research we have developed in order to generate the data in a way that is readily usable for researchers worldwide. The first half of this thesis will give a brief overview of UK Biobank brain imaging and the acquisition protocol, and then describe the processing pipeline and QC pipeline in detail. We also describe several quantitative investigations carried out as part of the development of both the imaging protocol and the processing pipeline. The second part of this thesis will show the research we performed to come up with a set of recommendations to deal with confounds in brain imaging studies using UK Biobank. UK Biobank is a powerful resource for studying associations between imaging and non- imaging measures such as lifestyle factors and health outcomes, in part because of the large subject numbers. However, the resulting high statistical power also raises the sensitivity to confounding effects, which therefore have to be carefully considered. Here we describe a set of possible confounds (including non-linear effects and interactions) that researchers may wish to consider for their studies using such data. We include descriptions of how we can estimate the confounds, and study the extent to which each of these confounds affects the data, and the spurious correlations that may arise if they are not controlled.