‘Mo Rùn am Fearann’ – ‘My Love is the Land’: Gaelic landscapes of the 18th and 19th centuries

The period of the 18th and 19th centuries was one of great change in the Highlands and Islands of Scotland. Improvement, the Jacobite Rebellions, and the Clearances transformed its communities and landscapes. These events have rightly been a focus of research. However, archaeological approaches have often sought simply to illustrate these processes, rather than create new narratives about life in the past. The resulting picture of the period can over-emphasise economic change whilst failing to reflect the richness and variety of everyday life. This thesis aims to suggest a new approach to the place and period, one which addresses matters often ignored in previous work. Whilst it has an archaeological sensibility, it draws on ideas from outside archaeology, such as landscape theory and on Gaelic oral tradition, an underused resource, to create a novel and broad-based approach to the period. An important part of the method is a synchronic approach that seeks to reconstruct the experience of the landscape at very particular times, engaging fully with the everyday experience of landscape rather than grand historical narratives. Two Hebridean case studies are utilised: Hiort (St Kilda) and Loch Aoineart, South Uist. Thematic discussions drawn from these landscapes are intended as critical assessments of the efficacy of the approach, as well as new narratives about life in the past in themselves. The thesis concludes by comparing the two case studies, reflecting on the merits of the approach, discussing recurrent themes in the work, and considering its wider context and implications. It is concluded that taking a novel approach to the case study landscapes can create narratives that often contrast or expand upon those produced by previous scholars, allow for a more detailed consideration of everyday life in the period, and open up new areas for archaeological enquiry. The extensive and critical use of evidence from Gaelic oral tradition is highlighted as crucial in understanding life and society in the period. The thesis questions the utility of grand historical narratives as a framework for archaeological study of post-medieval Gaeldom and suggests that our understanding of the past is best served by approaching the evidence in ways which allows for many different voices and stories from the past to emerge.

The impact of denture related disease on the oral microbiome of denture wearers

Advances in healthcare over the last 100 years has resulted in an ever increasing elderly population. This presents greater challenges for adequate systemic and oral healthcare delivery. With increasing age there is a natural decline in oral health, leading to the loss of teeth and ultimately for some having to wear denture prosthesis. It is currently estimated that approximately one fifth of the UK and US populations have some form of removable prosthesis. The microbiology of denture induced mucosal inflammation is a pivotal factor to consider in denture care management, similar to many other oral diseases of microbial influence, such as caries, gingivitis and periodontitis. Dentures support the growth of microbial biofilms, structures commonly known as denture plaque. Microbiologically, denture stomatitis (DS) is a disease primarily considered to be of yeast aetiology, with the literature disproportionately focussed on Candida spp. However, the denture surface is capable of carrying up to 1011 microbes per milligram, the majority of which are bacteria. Thus it is apparent that denture plaque is more diverse than we assume. There is a fundamental gap in our understanding of the bacterial composition of denture plaque and the role that they may play in denture related disease such as DS. This is categorised as inflammation of the oral mucosa, a disease affecting around half of all denture wearers. It has been proposed that bacteria and fungi interact on the denture surface and that these polymicrobial interactions lead to synergism and increased DS pathogenesis. Therefore, understanding the denture microbiome composition is the key step to beginning to understand disease pathogenesis, and ultimately help improve treatments and identify novel targets for therapeutic and preventative strategies. A group of 131 patients were included within this study in which they provided samples from their dentures, palatal mucosa, saliva and dental plaque. Microbes residing on the denture surface were quantified using standard Miles and Misra culture technique which investigated the presence of Candida, aerobes and anaerobes. These clinical samples also underwent next generation sequencing using the Miseq Illumina platform to give a more global representation of the microbes present at each of these sites in the oral cavity of these denture wearers. This data was then used to compare the composition and diversity of denture, mucosal and dental plaque between one another, as well as between healthy and diseased individuals. Additional comparisons included denture type and the presence or absence of natural teeth. Furthermore, microbiome data was used to assess differences between patients with varying levels of oral hygiene. The host response to the denture microbiome was investigated by screening the patients saliva for the presence and quantification of a range of antimicrobial peptides that are associated with the oral cavity. Based on the microbiome data an in vitro biofilm model was developed that reflected the composition of denture plaque. These biofilms were then used to assess quantitative and compositional changes over time and in response to denture cleansing treatments. Finally, the systemic implications of denture plaque were assessed by screening denture plaque samples for the presence of nine well known respiratory pathogens using quantitative PCR. The results from this study have shown that the bacterial microbiome composition of denture wearers is not consistent throughout the mouth and varies depending on sample site. Moreover, the presence of natural dentition has a significant impact on the microbiome composition. As for healthy and diseased patients the data suggests that compositional changes responsible for disease progression are occurring at the mucosa, and that dentures may in fact be a reservoir for these microbes. In terms of denture hygiene practices, sleeping with a denture in situ was found to be a common occurrence. Furthermore, significant shifts in denture microbiome composition were found in these individuals when compared to the denture microbiome of those that removed their denture at night. As for the host response, some antimicrobial peptides were found to be significantly reduced in the absence of natural dentition, indicating that the oral immune response is gradually impaired with the loss of teeth. This study also identified potentially serious systemic implications in terms of respiratory infection, as 64.6% of patients carried respiratory pathogens on their denture. In conclusion, this is the first study to provide a detailed understanding of the oral microbiome of denture wearers, and has provided evidence that DS development is more complex than simply a candidal infection. Both fungal and bacterial kingdoms clearly play a role in defining the progression of DS. The biofilm model created in this study demonstrated its potential as a platform to test novel actives. Future use of this model will aid in greater understanding of host: biofilm interactions. Such findings are applicable to oral health and beyond, and may help to identify novel therapeutic targets for the treatment of DS and other biofilm associated diseases.