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This thesis examines the archaeobotanical evidence for settlement, cultivation, and woodland management in England during the early medieval period, here defined as the era between the 5th and 11th centuries AD. The research provides new perspectives on how the landscape and woodlands were managed for fuel and building materials and provides evidence of horticultural cultivation of food, craft, and medicinal plants. A multidisciplinary approach is taken combining carpological and anthracological analysis of primary archaeological material using the evidence from the settlements at Dando Close, Higham Ferrers and Flixborough in the East Midlands of England as principal case studies. This was supported by the creation of an extensive comparative data collection study of archaeobotanical records from early medieval Britain, as a whole. This research also provides the first application of a quantitative dendro-anthracological approach to English sites, exploring patterns of oak use in early medieval England. The outcomes of the dendro-anthracological study have yielded ground-breaking high-resolution evidence of timber and fuel wood collection strategies and woodland management regimes. The exceptionally well-preserved charcoal from the early medieval settlement of Flixborough has allowed a unique insight into the selection of timber for the renovation of buildings and possible long-term woodland management strategies undertaken in the area during the mid 8th to 9th century AD. To further support the research into horticulture and woodland management an experimental early medieval rural garden was created, with the purpose of providing essential experimental data to compliment the analytical research and to allow observations of the plants' growth habit as well as providing material to conduct reference analysis for the methodology and interpretation. The garden also functioned as an open-air laboratory for public engagement and outreach activities that were supported by a range of hands-on STEAM (science, technology, engineering, art, and maths) laboratory workshops. To help contextualise the archaeobotanical evidence, selected medieval textual sources are assessed, to explore documented horticultural and silvicultural strategies from the early medieval period, as well as the uses of wild and domestic plants for medicine.

This project explores the following research questions: How might Black Country fiction illuminate the possible connections - in theory and practice - between the post-industrial liminality of the region and queer identity or experience; and, in what ways might a close analysis of contemporary Black Country fiction function as an enabling or energising factor in the production of a new creative work about the region? Using Environmental Psychology and Psychogeography, I critically examine the ways the literature of the region depict its geography and the impact this has on the identity of its characters. Freudian and post-Freudian psychoanalysis is utilised to discuss ideas of liminal states of being - focusing on the uncanny, the abject and Lacan's Lamella. These ideas are set within the framework of Queer Theory, connecting place and identity with non-normative sexualities. Psychogeography and environmental psychology illustrate how one's culture, heritage and environment help form communal identity and sense of place. I examine sense of place in the region's literature and investigate the liminal aspects of its geography and socio-politics, exposing how liminal place affects the inhabiting cultures and communities, and how liminal place forges liminal experience and identity. I investigate identity by looking at literary depictions of abjection and the uncanny; using Freud, Lacan and Kristeva, this project looks at notions of coming into being, and the anxieties formed from the return of the repressed. Queer Theory focuses on non-normative desire and sexuality. I discuss how queer experience and identity can be read as liminal, uncanny and abject. These theories are set against the landscape of the Black Country, examining how the region can be used as a fruitful backdrop for dealing with identity politics and how the Black Country, in its borderlessness, plays a significant role in specifically local types of queerness. An important thematic thread of contemporary Black Country literature deals with notions of identity in a post-industrial landscape. The region can be identified as post-industrial in several ways. I examine how Black Country writers deal with it as a borderless place - a place difficult to map, a place where new meets old, where rural life sits next to heavy industry, a place geographically and socio-politically liminal. This thesis is a piece of literary criticism of existing Black Country Literature, an original piece of creative writing and a reflective commentary on my creative practices. Queering the Black Country investigates the research questions through three different methodologies, resulting in an overall conclusion that draws on three distinct academic / creative practices. The critical output sets out how Black Country writing can be read as examples of liminal, post-industrial and queer literature. This also develops the theoretical framework the creative element uses. The creative output develops and adds to the existing dialogue of these ideas of liminality and queer experience, offering an original creative perspective on the traditions of this region's literature. My reflective commentary explores how creative writing practices and processes, in terms of narrative devices, add to the ways one produces liminal and queer literature. This part critical - part creative project investigates slippery notions of liminality through criticism of existing Black Country literature and through production of an original piece of creative fiction.

Within the active zone of rivers, riparian vegetation dynamics are controlled by ecological and hydro geomorphological processes and their interactions. Within Europe, understanding of natural riparian tree establishment has been limited by a lack of unregulated, natural river systems. This thesis examines key biotic and abiotic factors influencing the establishment of three riparian tree species, Populus nigra, Salix elaeagnos and Alnus incana, that grow within the active zone of the River Tagliamento, a morphologically-intact alpine/mediterranean river in Northeast Italy. Field observation, field experimentation and greenhouse experiments indicate: (i) Interspecific and propagule form variations in survival and growth response to hydrogeomorphic conditions: P. nigra cuttings performed best in low free-draining sites with a small proportion of fine sediment but which were not subject to prolonged inundation, while seedlings preferred fine sediments and higher elevations. Salix elaeagnos cuttings performed best at lower elevations, with a preference for mixed sediments, and proved tolerant to drought and inundation. S. elaeagnos seedlings grew best at higher elevations and in coarse/mixed substrates. Alnus incana cuttings only grew in fine sediments under stable water levels in greenhouse experiments; mortality was total in field experiments. Deposited trees of an species survived better at lower elevations. (ii) Differences in growth rates according to propagule type: cuttings grew twice as fast as seedlings in the first year but not in the second, and whole deposited trees produced far higher levels of shoot growth and biomass. (iii) Timing of deposition in the growing season and size of propagule also significantly affected performance. These results suggest that species and propagule form directly influence the rate of vegetation establishment within the active zone of rivers and that plant physiology alongside hydrogeomorphology is critical to riparian vegetation dynamics. These results are explored in the context of the development of river islands, an endangered but ecologically important type of landform once common within natural, braided European rivers.

The aim of this study was to determine the effect of TIMP-1 and TIMP-2 on HSC survival and determine whether this effect was through effects on inhibition of MMP activity. In vivo studies of experimental liver fibrosis demonstrated a correlation between resolution of fibrosis, falling, TIMP-1 mRNA, loss of HSC and transient increase in collagenolytic activity. This data suggested that TIMP-1 was likely to have an effect promoting HSC survival. In vitro studies of culture activated HSC demonstrated that neither TIMP-1 nor TIMP-2 regulated HSC proliferation suggesting that the pro survival effect was likely to be via inhibition of apoptosis. Incubation with TIMP-1 or TIMP-2 significantly reduced apoptosis of HSC induced by a number of stimuli in a dose-dependent manner. Neutralising antibodies to TIMP-1 and TIMP-2 increased HSC apoptosis compared non-immune IgG control. Whilst both a synthetic selective inhibitor of MMP-2 and a broad spectrum synthetic MMP inhibitor reduced HSC apoptosis, a non-functional mutated TIMP-1 (T2G mutant) had no effect indicating that the inhibition of apoptosis by TIMP-1 was via inhibition of MMP activity. MMP-2 like TIMP-1 is expressed by activated HSC. Addition of recombinant active MMP-2 to HSC resulted in significantly enhanced apoptosis and was associated with cleavage of N-cadherin which could be reduced by co-incubation with recombinant TIMP-1 but not by the non-functional T2G mutant TIMP-1. Furthermore, selective MMP-2 inhibitors protected N-cadherin from cleavage. Active MMP-2 cleaves intact N-cadherin into similar sized fragments in vitro. Blockade of N-cadherin binding with blocking antibody or HAVDI blocking peptide promoted HSC apoptosis, suggesting N-cadherin is a potential target mechanism for the regulation of survival and apoptosis of HSC via active MMP-2 mediated cleavage. Finally, to determine if effects on apoptosis by TIMP-1 were through changes in cell-matrix interactions, HSC plated onto a mutated collagen that is resistant to degradation by MMP-2 were more resistant to apoptosis induced by active MMP-2 than HSCs plated onto normal wild type collagen-1.

This thesis starts by constructing a complex line bundle for a simple 3-parameter family of 2 x 2 Hermitian matrices and explicitly computing its first Chern number. This example illustrates in the simplest possible context the connection between topology and degenerate eigenvalues of matrices. The central part of this thesis then follows. We present a geometric, vector bundle view of a large class of parameter-dependent boundary-value problems. In particular, we consider holomorphic families of linear ordinary differential equation systems on a finite interval which are subjected to prescribed parameter-dependent boundary conditions. The Gardner-Jones bundle, which was introduced for linearized reaction-diffusion equations, is generalized and applied to this abstract class of lambda-dependent boundary-value problems, where lambda is a complex eigenvalue parameter. The fundamental analytical object of such lambda-dependent BVP's is the characteristic determinant, and it is proved that any characteristic determinant on a Jordan curve that contains no eigenvalues of the problem can be characterized geometrically as the determinant of a transition function associated with the generalized Gardner-Jones bundle. The topology of this vector bundle, represented by its first Chern number, then yields precise information about the total number of eigenvalues of the problem in any prescribed subset of the complex lambda-plane. This result shows that the generalized Gardner-Jones bundle is an intrinsic geometric property of such lambda-dependent BVP's. The thesis then applies the generalized Gardner-Jones bundle framework to various examples, including one from hydrodynamic stability theory and the linearized complex Ginzburg-Landau equation. The final parts of the thesis contain exploratory attempts at understanding the geometric structure of some classes of parameter-dependent periodic linear systems and multiparameter linear systems. In the latter case, we explore curvature 2-forms. The thesis ends by summarising the achievements of this work, and discussing the various possible directions and objectives for future investigations.

Since recent times the importance of wireless communications has experienced a phenomenal growth, thus incurring a considerable increase in usage of the frequency spectrum available for communications and hence creating the need for efficient methods for its utilisation. Multiple-access is one efficient method, which enables several users to share a common frequency bandwidth. A multiple-access technique known as Collaborative Coding Multiple Access (CCMA) has been theoretically investigated and has been shown to give an increase in channel capacity and bandwidth efficiency. This technique uses a special type of codes known as collaborative codes to enable multiple users to communicate simultaneously over a common frequency bandwidth, thus eliminating the use of time, frequency and orthogonal code divisions. However to implement this technique practically, requires a multiple access channel (MAC) that coherently combines the signals originating from different users to give a composite signal. The combining of signals to implement a CCMA scheme can be easily achieved in baseband channels, where signals can be represented as voltages or currents which can add, to give uniquely identifiable code combinations. However when extended to bandpass carrier channels, the combining of signals over radio channels involves the addition of signals of differing, and, in the mobile situation particularly, varying relative phases and amplitudes. This can give rise to a major detection problem due to the resulting destructive signal combining and thus making CCMA non- practical over radio channels. This thesis describes a novel multiple-access scheme known as Complex-Valued Collaborative Coding Multiple Access (CV-CCMA), to provide a practical system over radio channels that achieves the theoretical promises of CCMA. CV_CCMA overcomes the problem associated with the non-coherent combining of multiple signals over radio channels by employing a complex-valued collaborative code and a combined detection and channel estimation process to estimate the data of each user as well as their associated amplitude and phase variations induced by the channel. The research is initiated with the principles and the theoretical foundations of the CV_CCMA technique. A combined signal detection and channel estimation process is presented. The choice of a suitable collaborative coding scheme is investigated. The conditions for the selection of valid codesets are established for a given number of users, modulation levels and code length. In addition, the effect of channel fading is also investigated. AT-user M-PSK CV_CCMA system operating in Rayleigh and Rician fading channels, is modelled and simulated to establish the error-performance. The results from this investigation are obtained for different number of users and modulation levels. The effect of varying signal power levels is also investigated. Observing the obtained results an additional code selection condition is established for a Rician channel, with an improved error performance. The channel capacity of the CV_CCMA scheme operating in a flat Rayleigh fading channel is obtained. In a given T-user M-PSK CV_CCMA scheme the channel outputs result in multi-level signals. Therefore the channel capacity of CV_CCMA is compared with equivalent multi-level single access schemes. It is shown that the channel capacity of CV_CCMA is greater than the corresponding multi-level schemes. The theoretical channel capacity limits of CV_CCMA is also compared with the limits of TDMA, FDMA and CDMA operating in a flat Rayleigh fading channel. The enhancement of the error performance of CV_CCMA in fading channels is investigated by using space diversity reception and error-control coding. It is found that by using these techniques the error performance of CV_CCMA can be greatly enhanced. For example with a dual-diversity scheme in a flat Rayleigh fading channel, the achieved gain is in the order of 20 dB. Using error-control coding, a coding gain is achieved depending on the type of code used. It is also found that using both of these techniques contributes towards further performance gains depending on the number of diversity paths and the coding scheme. The thesis is finally concluded with an overview of the contributions of this thesis, the achieved results and their implications and suggestions for future work in this subject.