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Thin film heterostructures, combining layers of materials with different magnetic properties, have received high levels of attention as they often exhibit new behaviour not seen in the individual layers. In particular, heterostructures utilizing ferrites have shown modified magnetic properties, and have found applications in spin-filtering magnetic tunnel junctions and insulator spintronics. In this work, we investigate pulsed laser deposition grown CoFe2O4 (CFO) and NiFe2O4 (NFO) single films and heterostructures. NFO is of interest due to its large exchange splitting, its ability to form insulating or conducting phases depending on its growth conditions, and the possibility to control its magnetic anisotropy through strain. CFO, on the other hand, exhibits a large positive cubic magnetocrystalline anisotropy constant compared to other ferrites, high magnetostriction, and low conductivity. The difference in the magnetic anisotropy and electronic properties between NFO and CFO, but similar crystal structure, provides the motivation to combine them into a heterostructure. For this purpose, we have studied single films of CFO and NFO as well as bilayers of NFO/CFO and CFO/NFO grown on Al2O3 [001] with different thicknesses. Here we present how interfacial effects, such as exchange coupling and strain, affect the magnetic properties and structural properties of single films and heterostructures. Polarised neutron reflectivity (PNR), X-ray reflectivity (XRR), X-ray diffraction (XRD) and vibrational sample magnetometry (VSM) have been used to characterise samples' magnetic and structural properties. Of particular importance, PNR was utilized to measure magnetic profiles as a function of depth across the chemically different layers. We first study [111] orientated CFO and NFO single films to investigate their growth on the strained ALO substrate and to have reference magnetic properties for later comparison to heterostructures. Both films showed a lower than bulk magnetisation, indicating anti-phase boundaries (APBs) defects play a large role in their magnetisation. A difference in chemical and magnetic profiles between NFO and CFO indicated a differing strength of effect from the ALO [001] interface on the density of APBs. We have then investigated bilayer samples of [111] orientated bilayers of CFO and NFO. Modified hysteresis loops and coercive field (Hc) values of the bilayers show evidence of exchange coupling. Certain magnetic properties of the bilayers depend on the layer thickness and growth order, i.e. CFO/NFO or NFO/CFO, on the ALO substrate. The measurements show an overall relative increased magnetization of NFO when grown on top of CFO, and depending on the layer order of the bilayer CFO and NFO show different Hc values. The changes in moment imply strain-related effects from the highly lattice mismatched substrate. The changes in Hc can be explained by a combination of strain-related effects, exchange coupling and layer thickness.

Seventy-five years after the arrival of its significant number of post-WW2 displaced persons and refugees, Scotland's Ukrainian community remains much understudied. The paucity of information concerning this community prompts deeper inquiry. Interdisciplinary research here focuses on this third wave of Ukrainian migration from homeland territories (1940-1954) and draws from a quadratic nexus of diasporic typologies, theories of identity maintenance, nationalist ideologies, and modes of assimilation. I briefly chart the community's historiographical and geo-political pathways where Ukrainians entered Scotland as officially designated stateless persons or 'aliens.' My interpretivist, ethnographic fieldwork conducted between 2014 and 2020 is focused on the salient, socio-cultural, and political dynamics of the first two generational cohorts. The interplay of social, cultural, and political complexities studied here is linked to élite actor attempts to identify and unify the settling community by the creation of formal organisations. A historiography of Ukrainian post war dispersion, homeland orientation and diasporic boundary creation is assisted by narrative extracted from semi-structured interviews, conversations, photo elicitation and embedded research. Concluding scrutiny of the founding generational cohorts is assisted by employing Robin Cohen's four tools of social science-the emic/etic relationship of embedded research, the time dimension, common diasporic features, and analysis of Weberian ideal types. The first generation is identified as a 'victim diaspora' while analysis of the second generation, the 'bridging cohort' opens discussion concerning the synergies and impact of collective memory. Qualitative research, quantitative evidence and analysis of hitherto unavailable primary source materials bring new synthesis and knowledge to the discourse.

The vagaries of Indian monsoon rainfall have profound consequences, but improved forecasting, on all timescales, has proved elusive. Subseasonal variability significantly influences interannual variability. However, a wide range poorly understood processes and feedbacks control the variability. Systematic model biases persist, with moist convection a dominant source of error. Cumulus scale biases can grow upscale to affect synoptic scales in two days, and the largest scales in two weeks. The onset of the monsoon rains progresses northwards over India over about 6 weeks, the reasons for which are not well understood. This is shown, primarily using radiosonde data, to be related to a mid-level dry layer, which retreats in response to closely related thermodynamic and dynamic transitions. The dry mid-level layer does not, however, significantly control the interannual variability of the onset. Systematic rainfall biases in models with convective parametrisations typically include a Western Equatorial Indian Ocean (WEIO) wet bias, an Indian dry bias, and too weak lowlevel flow into India. Explicitly representing convection, in continental-scale simulations, is shown to reduce the dry bias and alters circulation and fluxes to sustain more rainfall over northern India. WEIO rainfall is too high in convection-permitting simulations with grid-spacings above ~2km, which also substantially alters the circulation. Towards a better understanding of the high rainfall upstream of the coastal mountains on the west coast of India, the role of offshore rainfall propagation is examined. Rainfall propagation likely results through storm advection and gravity waves, and varies in response to the passage of Boreal Summer Intraseasonal Oscillations. Contrary to satellite observations, rainfall consistently propagates onshore in convection-permitting simulations. The results demonstrate the importance of understanding scale interactions in the Indian monsoon. Improved models must capture storm-to-mesoscale processes that affect the entire monsoon.

This practice-based research articulates a performer's perspective from within the rapidly expanding field of mixed music, wherein traditional acoustic instruments are augmented by means of live electronics. Contemporary technology presents a panoply of sonic and interactive affordances and diverse avenues of potential for a contemporary practice of the clarinet. Pursuing a move from a technically passive approach towards self-efficient onstage operation, the author articulates a journey in which a hybridity of instrumental expertise and technical naivety develops into an embedded practice. A framework of humanising is proposed to establish codes of practice based on the embodied skill and priorities of the onstage performer. A pragmatic and personal approach emerges to managing issues of sound, control, and engagement, with an emphasis on viable rehearsal and performance practices that ultimately privilege an ongoing attention to liveness. The portfolio of sound recordings and the observances contained in this thesis contribute to a growing body of performer-led accounts in a rich environment for the development of new creative work and collaboration, and to facilitating access to interactive music for performers wishing to explore the field. A set of case studies trace three broad roles across a spectrum of creative agency within an interdisciplinary practice of the clarinet, situated at a nexus of diverse approaches - from performing composed works (executant interpreter) to non-idiomatic free improvisation (enactive composer), via hybrid works that blur these authorial distinctions (enabled interpreter). Negotiating multiple, interdependent influences within these respective performance ecologies, and moving over time from a status of technical novice towards one of proficiency and expertise (Dreyfus & Dreyfus 1980), a growing sense of embodied instrumentality is encountered (Nijs et al. 2009). The additional technology becomes less an extension of the instrument, rather the performer becomes present in a new holistic entity (Riva 2009; Rebelo 2006), with an attendant, ongoing re-evaluation of personal sound concept. Instrumental musicianship is reframed as inhabiting an assemblage of tools that filter and resonate physical energy, identity, and culture, and is directed towards an optimal performing presence.

This thesis is an analysis of the manner in which the persona and works of Ben Jonson were appropriated – between the Restoration, in 1660, and the retirement of David Garrick, in 1776 – to reflect the political and social concerns of the age. Unlike previous studies, rather than primarily focusing on the stage history of Jonson, I analyse a wide range of sources – produced both within and outwith the theatre – in order to explore, across a variety of media, a breadth of material which appropriates the playwright and his works. I shall consider in my first main chapter the appropriations of Jonson within the Restoration court, in particular noting the assimilation of the playwright's work to what might be styled a proto-Tory ideology, as well as the way in which his plays could mirror the destabilising effects of the king's romantic liaisons. In my second chapter, I explore the moral reformation at the turn of the eighteenth century, in which we can see appropriations of Jonson which cast his works as being primarily didactic. The third chapter moves the narrative of the thesis into the years of the premiership of Sir Robert Walpole. I shall consider the way in which the playwright's works – especially The Alchemist and Eastward Ho! – were seen as being especially relevant to an age of speculation and mercantile endeavour, as well as examining the manner in which the figures of Sejanus and Volpone were appropriated to mock the increasingly unpopular premier. In the final chapter, I shall offer an analysis of Garrick's seminal portrayal of Drugger in the contexts of the political philosophy of the mid-eighteenth century, considering the manner in which it was interpreted alongside the character's further appropriations by Francis Gentleman. The thesis concludes by exploring political appropriations of Jonson up to the present day.

Over the last two decades, campus redevelopment in the UK and worldwide has accelerated. University building activity is frequently justified by architects and managers as responding to 'market forces'. These claims are reflected in institutional discourses about campus redesign and a growing academic and media interest in the organisational space of universities. Discourses often emphasise the positive transformative effects of redevelopment without considering the wider impact on the everyday life of the university. This thesis explores the relationship between institutional space and the construction of individual, social and professional identities, using a case study describing a ten-year campus transformation project at Manchester Metropolitan University. Over this period, the university aimed to: consolidate the number of individual campuses from seven to two; provide new 'world-class' facilities for staff and students; create opportunities for 'improved' teaching and research activity; and develop the university brand. In real terms, this meant closing existing campus locations and relocating staff and students to an 'iconic' new building containing open plan academic offices and flexible student pods. The management discourse around this ambitious building project revealed a deterministic stance, predicting a variety of 'improvements' to academic working practices, student satisfaction and efficiency as a result of these environmental changes. Viewed as a whole, these spatial manipulations were intended to influence internal and external perceptions of identity and act as an indicator of successful change management. Three interpretive approaches are used to examine the social production of a new university space: thematic; visual; and dispositive analysis. The analysis uses the work of Lefebvre, Foucault, and de Certeau to argue that specific discursive, non-discursive and material/spatial techniques are bound together in the imaginations of university management. These techniques are then employed to dismantle 'outdated' working practices in an attempt to 'spatially fix' particular new conceptions of academic labour and professional identity that fit with the neo-liberal university project. Lefebvre's spatial triad is used to structure the discussion around three research questions that focus on the creation of identities via the conceived space of institutional designers, the perceived space of work activities and the emotionally lived space of university life in the new building. The research revealed a conceptual void apparent in the design of university buildings where spatial aesthetics are appropriated from other sectors to 'fix' the problems inherent in academic capitalism. The data show how particular spatial arrangements are used to discipline academic labour and encourage particular managerially sanctioned working practices. The thesis also demonstrates the lack of recognition given to physical artefacts and personalisation of space in the design of academic offices and the detrimental effect that this has on staff identity.

Feedback Linearisation (FL) is a nonlinear control technique that has gained a lot of attention in the past 30 years. Due to its relatively simple synthesis, the use of FL has been investigated particularly in the aerospace community, because aircraft models are often highly nonlinear and a controller is needed that can guarantee good performance over a wide range of operating conditions. However, mathematical models of real-life physical systems always have a level of uncertainty on them, as they are only ever approximations to the real system. In the current literature, the robustness of FL control has been analysed by extensive simulations, which may miss some worst-case combinations of uncertainties in the model. Alternatively, the robustness of the controlled system has been analysed on simplified linear models, using techniques from classical control, which do not well represent the inherently nonlinear dynamics of the system. This thesis contributes to the literature by using more recent techniques for analysis of nonlinear systems to assess robust stability under FL control. We apply advanced robust and nonlinear analysis techniques without the assumption that the controller has direct access to all the states of the system, by including state estimation or sensors in the closed loop for analysis. We also develop an existing analysis technique in the literature to show that a system under approximate FL control does not violate position limits of the actuator, despite uncertainty in the model, improving the rigour of the analysis. This is applied to a high-fidelity model of an aircraft, designed for use in industry and academia.

This thesis provides a critical application of Robert P. George’s views to English equality law. The research question is what George, with his view of religion as a basic human good, might think about the religious liberty cases taken under the provisions of the Equality Act 2010. In addressing this question, it will be necessary to look at those - to some eyes - irreconcilable tensions which have emerged between laws protecting religious freedom. A number of legal claims have been brought by employees who have been instructed to carry out new legal obligations which they have been unwilling to perform. Questions have arisen regarding the current state of reasonable accommodation and proportionality analysis within indirect discrimination law. To examine these questions, this thesis will be in two parts: first, it will consider Robert George’s distinctive contribution to new natural law theory (NNL) and critically analyse George’s NNL approach that arises from this. To do so the key themes: a) practical reason and b) natural rights, will be considered in George’s work. Second, by reading George’s views on practical reason in line with his approach to natural rights, from this position this thesis will give an applied example of NNL, displaying George’s critique of the relevant equality law and arguing for an innovative understanding and approach to religious equality law. This is in an effort to find whether George’s theory is useful in exploring English religious equality law. By doing so this will reconstruct George’s NNL approach through using religious equality law as an applied example. This thesis argues that at a time when religious liberty often loses out in a balancing of rights, legitimate interests and protected characteristics, a superior way to approach equality law in this area may be through an application of a modified version of George’s NNL thought presenting religion as a public good. This will emphasise the priority of the good in religious conscience over legal rights within law viewed by George as a public morality. Viewing religion not only as a basic human good but also as a public good could provide the basis for future accommodation towards freedom of religious conscience and solve the tensions regarding the protection of religion or belief at work. Religion and religious freedom will be shown to be a form of flourishing within an understanding of the public good.

Colorectal cancer (CRC) patients are stratified by the Tumour, Node and Metastasis (TNM) staging system for clinical decision making. Additional genomic markers have a limited utility in some cases where precise targeted therapy may be available. Thus, classical clinical pathological staging remains the mainstay of the assessment of this disease. Surgical resection is generally considered curative for Stage II patients, however 20-30% of these patients experience disease recurrence and disease specific death. It is imperative to identify these high risk patients in order to assess if further treatment or detailed follow up could be beneficial to their overall survival. The aim of the thesis was to categorise Stage II CRC patients into high and low risk of disease specific death through novel image based analysis algorithms. Firstly, an image analysis algorithm was developed to quantify and assess the prognostic value of three histopathological features through immuno-fluorescence: lymphatic vessel density (LVD), lymphatic vessel invasion (LVI) and tumour budding (TB). Image analysis provides the ability to standardise their quantification and negates observer variability. All three histopathological features were found to be predictors of CRC specific death within the training set (n=50); TB (HR =5.7; 95% CI, 2.38-13.8), LVD (HR =5.1; 95% CI, 2.04-12.99) and LVI (HR =9.9; 95% CI, 3.57- 27.98). Only TB (HR=2.49; 95% CI, 1.03-5.99) and LVI (HR =2.46; 95%CI, 1 - 6.05), however, were significant predictors of disease specific death in the validation set (n=134). Image analysis was further employed to characterise TB and quantify intra-tumoural heterogeneity. Tumour subpopulations within CRC tissue sections were segmented for the quantification of differential biomarker expression associated with epithelial mesenchymal transition and aggressive disease. Secondly, a novel histopathological feature ‘Sum Area Large Tumour Bud’ (ALTB) was identified through immunofluorescence coupled to a novel tissue phenomics approach. The tissue phenomics approach created a complex phenotypic fingerprint consisting of multiple parameters extracted from the unbiased segmentation of all objects within a digitised image. Data mining was employed to identify the significant parameters within the phenotypic fingerprint. ALTB was found to be a more significant predictor of disease specific death than LVI or TB in both the training set (HR = 20.2; 95% CI, 4.6 – 87.9) and the validation set (HR = 4; 95% CI, 1.5 – 11.1). Finally, ALTB was combined with two parameters, ‘differentiation’ and ‘pT stage’, which were exported from the original patient pathology report to form an integrative pathology score. The integrative pathology score was highly significant at predicting disease specific death within the validation set (HR = 7.5; 95% CI, 3 – 18.5). In conclusion, image analysis allows the standardised quantification of set histopathological features and the heterogeneous expression of biomarkers. A novel image based histopathological feature combined with classical pathology allows the highly significant stratification of Stage II CRC patients into high and low risk of disease specific death.

In this thesis I investigate the hosts and cluster environments of a sample of 41 radio galaxies between z = 0.4 and z = 0.6. I use spectroscopic data for a 24 object subsample to investigate their star formation histories via the strength of the 4000A break. I find that the higher radio luminosity or high excitation objects in the sample have evidence for young stellar populations, but the lower radio luminosity or low excitation objects do not. My investigations into the Fundamental Plane (FP) of 18 of the radio galaxies, using the same spectroscopic data as well as data from the literature, show that the Fanaroff- Riley type I objects (FRIs) lie on the FP of local radio galaxies once corrected for passive evolution but the Fanaroff-Riley type II objects (FRIIs) do not. I suggest that an evolution in the size of the host galaxies, aided by a combination of passive evolution and a mass-dependent evolution in the mass-to-light ratios, may explain the observed offsets. Finally, I use wide field multi-band imaging to investigate the cluster environments of the full z ~ 0.5 sample. I find that the environmental overdensity is positively correlated with the radio luminosity and observe a greater number of close companions around the FRIIs than the FRIs (albeit with only nine FRIs in the sample). The cluster environments of the radio galaxies with the greatest host luminosities show tentative evidence for an alignment between the major axis of a galaxy and that of its cluster, whilst there are hints that the objects with the highest radio luminosities have clusters whose major axis is aligned with the position angle of the radio jet. My results suggest a picture in which FRII type radio sources reside in particularly rich cluster environments at z ~ 0.5 but FRI type radio sources in less rich environments. The environment plays a key role in determining both the radio properties of the galaxy and the evolution of its host. The effect of the environment on the emission line properties and star formation histories of the galaxies leads to the overlap seen in the morphological and spectral properties of radio galaxies.

Degraded DNA can be recovered from specimens that are preserved in museums and the natural environment. Data generated from such DNA have provided valuable evidence for the assessment of a suite of biologically important questions. However, research of this nature is limited for invertebrate taxa, despite their diversity and ecological necessity. Using DNA data from dry-stored museum and permafrost-preserved ancient specimens, this thesis greatly extends the study of degraded DNA from invertebrates. The thesis focuses on two arctic ground beetle species (Amara alpina, Pterostichus brevicornis), which are abundant in museum collections and permafrost deposits. A lack of data that characterises the preservation and potential of degraded beetle DNA, and thereby assessment of future possibilities for this emerging field, provided the impetus for the first three results chapters. Using two different sequencing approaches, the preservation of DNA in museum and ancient specimens was investigated. In addition, the taxonomic utility of DNA extracted from these specimens was assessed. These chapters demonstrate that DNA could be routinely recovered from museum specimens. DNA from ancient specimens could be recovered from A. alpina but not P. brevicornis. In most cases therefore, degraded DNA from these beetles could be used to address further questions. The final two results chapters focus on the response of the two study species to a past period of climatically driven change, using DNA data from museum and ancient specimens. In these chapters, the mode of postglacial colonisation of Canada at the end of the last ice age was investigated. It was found that existing models of this process were broadly, but not wholly, correct. This may have implications for models of how beetles will respond to future climatic change. Although some challenges lie ahead, this thesis demonstrates the potential for museum and ancient permafrost-preserved beetle specimens in future, DNA-based, large-scale investigations.

This thesis is concerned with the open magnetic flux content of the magnetosphere during the substorm cycle. We develop an automated technique of identifying the global location of the open/closed magnetic field line boundary (OCB) from auroral images of the ionospheric northern polar cap made by the IMAGE FUV detector, and hence of estimating the open magnetic flux content of any one hemisphere (Fpc). Systematic offsets are found between the location of the OCB as estimated from the auroral images and from in-situ measurements of precipitating particles consistent with previous studies. These offsets are used to provide a more accurate global estimation of the location of the OCB. This method is used to estimate the average Fpc content of the magnetosphere from 12,731 auroral images from December and January of 2000-2002, 173 of which occur at the time of substorm onset. From these distributions we are able, for the first time, to determine the probability of substorm onset as a function of Fpc. The probability of substorm onset is found to be negligible below ~ 0.3 GWb, increases linearly until ~0.9 GWb, and is undefined above this. These results are discussed in terms of various models for substorm onset and place important constraints on any future models. We also find that substorms showing a clear particle injection signature, as seen at geosynchronous orbit, occur, on average, at higher values of open magnetic flux than those showing varied or no injection activity. In the final part of this thesis we investigate these three distinct categories of substorms further by carrying out a superposed epoch analysis of Fpc, maximum nightside auroral brightness, solar wind and IMF conditions, geomagnetic activity and auroral oval boundary motions. We find that the level and form of solar wind driving appears to characterise the injection signature seen.

This thesis is concerned with ensuring high energy resolution from the swept charge device (SCD) CCD54, essentially a non-pixellated version of the charge coupled device (CCD), for use in the Chandrayaan-1 X-ray Spectrometer (C1XS). Of particular interest is the effect on performance due to the radiation damage, caused by protons, the CCD54s used in C1XS will receive during the transfer to the Moon and during the two years in lunar orbit. Chapter 2 reviews the atomic structure, the formation and detection of X-rays, and the operation of a CCD. Chapter 3 discusses the space radiation environment and the damaging effects it has on CCDs, for example increasing dark current and charge transfer inefficiency. Chapter 4 presents the basic laboratory equipment and procedure used during the experimental work, and details the initial optimisation and characterisation, the pre-flight characterisation of devices available for use in C1XS, the measurement of the depletion depth, and quantum efficiency of the CCD54. Chapter 5 details the results of the initial proton irradiation study, intended to demonstrate the ability of the CCD54 to provide excellent scientific data over the two years at the Moon. Chapter 6 describes a second irradiation study covering a more detailed investigation of the damage effects, investigating dark current, trap energy levels, and charge transfer inefficiency. Chapter 7 describes work conducted to assist the C1XS science team in the development of an X-ray fluorescence model, to be used with X-ray spectra provided by the X-ray solar monitor and the spectra detected by C1XS, to provide elemental abundance information of the lunar surface. It also presents the initial C1XS results from the Moon, and a brief comparison of the CCD54 with other semiconductor X-ray fluorescence detectors. Chapter 8 describes the final conclusions and recommendations for further work, including a study of the radiation damage effects during the two years at the Moon and the future development of SCD detectors for use in space.

The Albury and Powerscourt prophetical conferences saw the birth of a new form of premillennial dispensationalism that has shaped evangelical eschatology ever since. It owed its debut to John Nelson Darby, who espoused the centrality of the "two peoples of God." Dispensationalism affirmed three cardinal doctrines: first, a sharp dichotomy between the two peoples of God-national Israel and the church; second, God's glory rather than the covenant of grace defining His purpose in history; and third, the hermeneutical principle of a literal interpretation of Scripture. This dispensationalism was indeed revolutionary, displacing the traditional historicist hermeneutic, with its system of date-setting, in favour of futurism, with its doctrine of imminency. This forced Darby to deal with the problem of what to do with the church so that God could fulfil his redemptive plan regarding national Israel. He resolved this by providing for a rapture of the church and by inserting a gap of an indeterminate number of years in the last part of Daniel's seventy-week prophecy. The question that arises over this new doctrine of premillennial, pretribulational dispensationalism concerns its provenance, since Darby is widely credited as its originator. There is good reason for this. His influence can be seen in C. I. Scofield's Reference Bible, as well as such popular novels as Hal Lindsey's The Late, Great Planet Earth and Timothy LaHaye's Left Behind series. There are two dominant schools of thought regarding Darby and the origin of dispensationalism. One traces his dispensationalism back to the Patristic Writings, and the other sees Darby as "inventing" his system. Both are incorrect, as I will demonstrate by tracing his eschatology to earlier thinkers to show that Darby "adapted" extant doctrines to form his unique system. This dissertation will establish a much more coherent picture of Darby and his contribution to the field of eschatology by identifying the sources that were available and were adapted by him to form his premillennial dispensationalism. This will also provide a greater understanding of the modern "revisionist" and "progressive" forms of dispensationalism.

This qualitative research is an exploration of the experiences of student teachers during teaching practice as a component of initial teacher education in Malawi. The research was necessitated by a general lack of knowledge about secondary school teacher education in Malawi and the view that teaching practice is one of the major components of concern for professional learning among student teachers. An activity theory perspective provided a theoretical and conceptual lens of understanding teaching practice. The elements within activity theory which were of particular significance related to tools/artefacts, subjects, objects and outcomes in teaching practice; rules/norms within an activity system of teaching practice; perceptions of individuals about teacher education and a teaching activity; pedagogical actions and understanding during teaching practice; the community relationships in school systems where student teachers carried out teaching practice; division of tasks; activity settings; tensions/contradictions, as well as innovations within the activity of teaching practice (Engestrom, 1999). The participants in the study were drawn mainly from student teachers on a three-year teacher education programme at one of the teacher education institutions in Malawi. The results from the study showed that the student teachers had different perceptions for teaching as well as differing goals for joining a secondary school teacher education programme; that student teachers had varied experiences during teaching practice and the varied experiences influenced learning to teach in various ways. The shortage of material resources impeded some activities that student teachers could carry out. The findings showed that some pedagogical tools that student teachers had learned in college were not always easily used in the schools. The community relationships between student teachers and teachers in the schools affected professional development in some way. The supervision component of teaching practice also generated mixed experiences from student teachers. The study participants proposed innovations aimed at resolving some of the tensions and contradictions faced during teaching practice. The innovations related to facilitative supervision, holistic assessment, changing the time and duration of teaching practice as well as student teachers' placements. The enriched understanding of the experiences of the student teachers makes significant contribution to knowledge within teacher education in Malawi.

Optical communication was developed to allow high-speed and long-distance data transmission and is currently a £6bn market. This has also led to the adoption of optical technologies in other areas including the CD, DVD and medical imaging systems. Standardisation of components means that these systems require light sources that operate near the 1310 and 1550 nm telecommunications windows but existing lasers here are expensive due to their high temperature sensitivity. The exploitation of quantum con¯nement has led to the development of \quan- tum dot" (QD) laser material because of predictions of huge gains in performance. Emission wavelengths of InAs/GaAs QD lasers have been extended to the telecom- munications window near 1300 nm by various growth technologies and the first commercial devices have recently been brought to the market. However, progress to longer wavelengths has been stalled for several years as well as the speed and tem- perature sensitivity of these devices falling short of the predictions; partly because QDs are grown by self-assembly resulting in a random distribution of sizes, compo- sitions and strain-states, leading to inhomogeneous broadening which is a departure from the ideal \atom-like" system. This work details the growth, design and development of QD bilayer laser devices, which o®er a unique approach to fixing these shortcomings. When two QD layers are grown close together; the first layer provides a template that allows larger, more uniform QDs to be grown in the second layer, giving greater uniformity and deeper confinement. This has the potential to increase the efficiency and to achieve emission wavelengths out towards the more-commonly used telecommunications window at 1550 nm directly on GaAs substrates. Multiple bilayer laser diodes with inhomge- neous broadening of less than 30meV, lasing at up to 1430 nm and room-temperature photoluminescence at 1515 nm are shown. Despite the vastly reduced inhomogeneous broadening of QD bilayers, it is still found to be a relevant factor due to the change from de-localised geometries of quantum wells to an ensemble of separate QDs. It will be shown that understanding this is essential for describing the observed optical and electrical behaviour of the laser diodes.

This thesis addresses the governance of Nottinghamshire during the first thirty three years of the reign of Edward III. The time-frame is significant as it seeks to re-dress an imbalance in the study of provincial societies during the later Middle Ages, which hitherto have largely concentrated on the second half of the fourteenth and fifteenth centuries. The most important belief to be addressed is that those who were engaged in the governance of Nottinghamshire were drawn from a considerably wider section of society than is apparent from previous county or regional gentry-based studies. It will also demonstrate the close nature of the relationship between the shire and the crown, which manifested itself in a wide variety of channels of communication. Chapters one and two look at the formal structures of government in Nottinghamshire. The focus for these chapters will be upon the whole of the county, as this reflects the crown's approach to governance. Chapter one will address the offices of local government, and chapter two will look at the pivotal relationship between the locality and the crown, concentrating upon parliamentary representatives and petitions. These chapters will also assess the impact of war and the Black Death upon Nottinghamshire. For subsequent chapters, the geographical focus of the study will be reduced to that of south Nottinghamshire, which will facilitate a more in-depth analysis of law and order in chapter three, and landholding in chapter four. The study will then -conclude with a case-study upon a smaller area within south Nottinghamshire. Throughout, this thesis will address significant historiographical debates. The most important of which relates to the impact upon provincial societies and local government of bastard feudalism, and to the related debates over the vertical and horizontal ties of lordship, and to the existence or otherwise of an 'independent gentry', and of 'county communities'.

The application of supercritical C0₂(scC0₂) as a solvent for the synthesis of fine and bulk chemicals has been well documented; however its application as a solvent for the synthesis of pharmaceuticals is yet to be exploited fully. To address this issue, two synthetically important reactions have been investigated in scC0₂; chemoselective N-debenzylation and diastereoselective hydrogenation. Chapter 3 details the study of catalytic N-debenzylation in the presence of sensitive functional groups (COMe and Cl). It has been shown that selective N-debenzylation in the presence of a carbonyl (COMe) is difficult to achieve due to the high operating temperatures that are required to facilitate continuous flow debenzylation. N-debenzylation in the presence of chloro- substituents was also investigated. Dechlorination can be a major problem during this reaction however several different strategies were developed to suppress dechlorination including: (i) the correct selection of catalyst support; (ii) selective poisoning of a Pd catalyst; (iii) the addition of acids, such as H₂S0₄ to the reactant stream; (iv) the use of an aprotic co-solvent, such as THF. Chapter 4 covers progress made on the diastereoselective hydrogenation of the pharmaceutical intermediate, rac-sertraline imine. It has been shown that the hydrogenation reaction can be performed with excellent levels of chemo- and diastereoselectivity (cis:trans ratio of 97:3, 0.7 % by-product formation) by performing the reaction as a continuous flow process in the presence of scC0₂ All details of the apparatus, experimental and synthetic procedures are reported in Chapter 2.

The use of an A1N interlayer to allow the growth of crack-free AlGaN on a GaN template is investigated. The impact of using an A1N interlayer on the active region of a device is examined by investigating a series of GaN/AlGaN quantum well structures. It is observed by WBDF that the a-type dislocations generated at the A1N interlayer form ‘staircase’ structures in the quantum well stack where all dislocation segments are in edge orientation A model is proposed where misfit dislocation segments at each well interface are formed by climb, in contrast to the dislocation glide at the lowest interface that might be expected in other systems. Both HAADF imaging and conventional TEM are used to characterise a series of Al-GaN/GaN quantum cascade laser (QCL) structures. These devices have great potential in the field of fibre optic communication. Changes in the layer spacing near V-defects, and the effects that changing substrate from sapphire to bulk GaN have on the mechanisms for relaxation in this system are identified and discussed.

This dissertation marshals a range of new evidence to reconstruct the 12th to 13th century Buddhism and sacred art of king Jayavarman VII. It traces political and cultural roots reaching back to the rise of Tantric Buddhism in eighth century Pala India. It links developments in peninsular pre-Thailand and across the Korat plateau with 10 th century temple art and inscriptions in Cambodia, where a Buddhist revival was influenced by the yogatantras, the first Tantras opening the 'path of vajra' or Vajrayana. The evidence for Tantric Khmer Buddhism is gleaned from a new translation of a key Sanskrit inscription and from sacred relief carvings. An analysis of the 11-12th century sacred art of Phimai, a major foundation in modern Northeast Thailand, evinces the arrival of the mature Vajrayanist yoginTtantras sustaining a Buddhist dynasty, which had seized power in Angkor and would later invest its religious beliefs in the Bayon. The phased building plan of Jayavarman VII's many temples and the iconography of the Bayon-style are reassessed, bringing to bear previously unpublished data from the king's large temple of Banteay Chmar northwest of Angkor. The reign of Jayavarman VII is substantially reconfigured, presenting his methodical introduction of new doctrine and consequent political dominance via carefully orchestrated stages which subjected the entrenched Brahmanical elite to politico-religious campaigns of consecrations to Lokesvara and ultimately to Hevajra and Vajrasattva. Throughout this thesis, exhaustive analysis is made of existing scholarship, which is confronted with a substantial body of new epigraphic and iconographic data.

The empirical focus of this thesis is the history of history teaching between 1880 and 1914. In particular, it constitutes a study of the intentions which underpinned wrical education. Much of the scholarly research on history teaching's past uses on the history lesson as a site for the downwards filtration of imperia, ideologies into the nation's consciousness, the source material for which has mainly been the subject-specific history textbook. The textbook, however, does not properly reflect the genre of text which the majority of children would have read in their lessons in history. This thesis shifts the focus and thus offers a contribution to knowledge by examining sources which, although largely absent in previous studies, play a significant role in helping us better understand the perceived values of historical education. This thesis, therefore, connects the recommended practice of the historical reading lesson and contemporary educational theory. It is the first substantial study to do so.

The osmium-mediated aminohydroxylation reaction is a powerful oxidation that introduces a hydroxyl group and a protected amino group in a syn relationship across an olefinic double bond. This study concerns one approach to controlling the regioselectivity of this oxidation. Introduction I The mechanism, scope and limitations of the aminohydroxylation reaction are discussed, with particular attention to the asymmetric version, providing a background from which the newly developed methodology has emerged. Results and Discussion I Development of the reaction This section concerns the original attempts to perform the tethered aminohydroxylation reaction, and early process optimisation to maximise the yield of aminohydroxylated product produced. Scope of the reaction This section details the results of the TA reaction as applied to further allylic carbamates demonstrating the applicability of the reaction to other olefinic geometries. The diastereoselectivity of the reaction in cyclic and acyclic systems is reported, and a model to explain the observed results discussed. Also covered within are the syntheses of the various substrates and proof of the stereochemistry of the products. Mechanistic investigations Work involving attempts to isolate a catalytic intermediate from the reaction is described. A crystal structure of this intermediate is discussed. Introduction II The isolation and physiological properties of the antibiotic compound hygromycin A are described. Prior synthetic routes towards this compound are discussed. Results and Discussion II Three approaches towards the aminocyclitol unit of hygromycin A, employing the tethered aminohydroxylation reaction, are outlined. Two of these allow for potential future development and completion of the synthesis.

When partially closed, steam turbine governing valves rely on flow separation from the valve head and seat to generate loss and throttle the flow. The aim of this type of valve is to avoid separation and therefore eliminate loss when the valve is fully open, and to have stable and controllable separations at all other valve lifts. Any significant unsteadiness in the valve flow can result in unacceptable mechanical vibration of the valve, which in extreme cases can lead to failure. Results will be discussed from work that has been undertaken into valve flow instabilities at Leicester University Engineering Department in collaboration with Alstom Energy Ltd. At high lifts, the Mach number of the steam flow between the head and the seat is sufficiently low for the fluid to be considered as incompressible. Water was therefore used as the working fluid in the tests at Leicester to model accurately the flow in a fifth scale acrylic model valve under high lift conditions. Results from laser light sheet visualisation, Particle Image Velocimetry and transient pressure measurements of the valve flow are presented. Laser light sheet illumination and high-speed Cine photography have been used to visualise the highly three dimensional valve flow. A range of valve head geometries has been tested. The results of the flow visualisation show the presence of stable and unstable separation zones and their influence on the valve flow. Particle Image Velocimetry has provided quantitative information on these features. Methods for stabilising the separation zones by modifying the valve head and seat have also been investigated and the results from these tests have shown improvements in reducing valve exit pipe unsteadiness.