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Oral tissue, including gingiva, is recognised for its ability to heal both at an accelerated rate and with reduced scarring. The aim of this project was to explore the contrasting healing efficiencies of gingival versus skin keratinocytes, alongside investigating their differential gene expression patterns. To achieve these aims, three‐dimensional (3D) organotypic culture models of human gingiva and skin were developed using temporarily immortalised primary keratinocytes. Wounding these models enabled the visualisation of re‐epithelialisation and analysis of keratinocyte migration and proliferation to close the wound gap. Concurrently, differentially expressed genes between primary gingival and skin keratinocytes were identified and validated. Immunofluorescence characterisation of the 3D cultures of gingiva and skin showed differentiation and junctional marker localisation that recapitulated organisation of the corresponding in vivo tissue. Upon wounding, gingival models displayed a significantly higher efficiency in re‐epithelialisation and stratification versus skin, repopulating the wound gap within 24 hours. This difference was likely due to distinct patterns of migration, with gingival cells demonstrating a form of sheet migration, in contrast to skin, where the leading edge was typically 1‐2 cells thick. A candidate approach was used to identify a number of genes, including PITX1, PITX2, PAX9, NOS1, HAS3 and SIM2 that were differentially expressed between human gingival and skin keratinocytes, both prior to and during wounding. Transient knockdown of the transcription factor PITX1 in gingival keratinocytes resulted in a significant reduction in wound closure in monolayer culture. The differences in cell migration, alongside the contrasting gene expression patterns, suggest that there are intrinsic differences between keratinocytes of the gingiva and skin that impact wound healing. Finally, the successful development of organotypic models that recapitulate re‐epithelialisation, will underpin further comparison of epithelial tissues in their response to wound stimuli, and potential therapeutic interventions, in an in vitro environment.

Much has been written over recent years questioning the value of exporting systems of VET from developed countries and expecting them to meet the needs and demands of developing countries. Most recently, the main recipients of development aid, particularly from the EU, have been the countries of the former 'eastern bloc'. As a consultant working on an EU project to upgrade VET in Bulgaria, the author was involved in delivering staff development seminars concentrating on 'new' teaching and learning strategies to teachers within the secondary vocational sector. Although the staff development was well received at the time, questions were raised about whether such fundamental changes in approach, from a very authoritarian and didactic approach, to an approach that is student-centred, could be sustained on the basis of a series of seminars. This thesis examines what impact these seminars have had in promoting the use of the 'new' strategies. In particular, the author examines to what extent cultural and / or contextual factors have played a role in the effectiveness of implementation of the 'new' student-centred teaching and learning strategies.

Photonic microstructures are a class of periodic dielectric structures which could lead to a significant evolution in optoelectronic devices. There are, however, several problems with photonic crystals, not least of which is the fabrication of these artificial structures. The fabrication of these artificial crystals in III-V semiconductor materials, specifically optical waveguide heterostructures, have been investigated. Improvements in the fabrication of GaAs/AlGaAs photonic bandgap structures have been made and the development of an AlAs epitaxial layer as a pattern transfer mask has been demonstrated. Two-dimensional photonic bandgap structures have been characterised and good agreement has been obtained between theory and experimental measurements. Subsequently, semiconductor microcavities incorporating photonic bandgap mirrors have been fabricated with mirror reflectivities higher than 90% and high mode Q factors, Q≈500. The results indicate that photonic bandgap technology has the potential to provide the desired engineering of the environment of a light emitter which will allow control of the emission process. The microstructuring of the material, however, creates significant obstacles to electroluminescence and much research in this area is required if any benefit of photonic microstructures are to be seen.

The expected role for women in 5th century Athens as presented in evidence from myths, rituals, medicine and religion was socially and biologically conceived of in strict terms, but it was also perceived as conflicted. This conflict will be explored by investigating women in real life and women in myth and ritual. The ideal rites of passage women were intended to pass through in their lives as exemplified in medical texts required women to shed their blood at appropriate times from menarche to marriage to motherhood. These transitions are socially signified by certain rituals designed to highlight the change in the individuals' status. This medical conception of the female body and its functions was affected by social expectations of the proper female role in society: to be a wife and mother. Myths presented extraordinary women as failing to bleed in the standard socially expected transitions from parthenos to gyne. The discrepancy between the presentation of women in social and medical thought and the presentation of women in myth indicates the ambiguities and difficulties that surround the development of girls into complete women often explored in rituals. These two provinces, women in everyday life and women in myth and ritual, overlap, relate and interpenetrate in the presentation of the goddess Artemis. Artemis operates in a place where myth and real life function together in the form of rituals surrounding women bleeding in these rites of passage. The methodology of social anthropology adopted in this study allows the interpretation of myth in action in women's lives and investigates where social ideals, mythology and the goddess Artemis overlap to inform the lives of women. Rather than merely describe what occurred in myth and ritual or what a woman's life was meant to be, this model will illustrate how such elements combined to affect a woman's life and the functioning of the society in which she lived. The picture which is created of the position of women when this evidence is considered in conjunction with the precepts of social anthropology illustrates part of a discourse about the position women and reveals how the social structure of their place in society was produced and reproduced.