“Something isn’t right here”: American exceptionalism and the creative nonfiction of the Vietnam War

In this thesis, I argue that few attempts were as effective in correcting the exceptionalist ethos of the United States than the creative nonfiction written by the veterans and journalists of the Vietnam War. Using critical works on creative nonfiction, I identify the characteristics of the genre that allowed Paul John Eakin to call it ‘a special kind of fiction.’ I summarise a brief history of creative nonfiction to demonstrate how it became a distinctly American form despite its Old World origins. I then claim that it was the genre most suited to the kind of ideological transformation that many hoped to instigate in U.S. society in the aftermath of Vietnam. Following this, the study explores how this “new” myth-making process occurred. I use Tim O’Brien’s If I Die in a Combat Zone and Philip Caputo’s A Rumor of War to illustrate how autobiography/memoir was able to demonstrate the detrimental effect that America’s exceptionalist ideology was having on its population. Utilising narrative and autobiographical theory, I contend that these accounts represented a collective voice which spoke for all Americans in the years after Vietnam. Using Neil Sheehan’s A Bright Shining Lie and C.D.B. Bryan’s Friendly Fire, I illustrate how literary journalism highlighted the hubris of the American government. I contend that while poiesis is an integral attribute of creative nonfiction, by the inclusion of extraneous bibliographic material, authors of the genre could also be seen as creating a literary context predisposing the reader towards an empirical interpretation of the events documented within. Finally, I claim that oral histories were in their essence a synthesis of “everyman” experiences very much in keeping with the American zeitgeist of the early Eighties. Focussing solely on Al Santoli’s Everything We Had, I demonstrate how such polyphonic narratives personalised the history of the Vietnam War.

The Shawlies: A study of early neoliberal ‘gender-fication’. The Street Trading Act, 1926, modern gender-fication, and the implications for Cork’s women street traders

For centuries Cork’s Shawlies, working-class women, survived by trading on public streets. My study explores how the first Irish Free State government, and Cork’s local authority, limited the rights of poor women to earn by subsistence trading with The Street Trading Act, 1926. The government insisted this would regulate street trading. In practice it further marginalised the women economically and socially, containing them outside the privileged, commercial city centre. In Cork the legislation facilitated the gradual disappearance of the Shawlies amid entrenched social processes and relations, contingencies that allowed for the abuse of their rights in the service of amalgamated business interests. This study address the role of discourses in deepening this marginalisation. My theoretical framework is designed to demonstrate how a seemingly innocuous piece of legislation would, in practice, do this. I set out the concepts of ‘Thriving State’, ‘Prosperous State’, and state of ‘Best Intentions’ that uses gentrification to meet these goals. The existing knowledge on women in trade is then examined, highlighting the gaps in what is known about the Shawlies. Chapter 3 details the theory behind my genealogical method. The legislation, debate, and other data produced at the national level is then examined, before moving to the local data. Chapter 6 is devoted to the Shawlies, setting their stories in the larger context of the debates. An examination of studies of contemporary women street traders in poor nations follows, along with a brief history of the decline of street trading in New York city under gentrification. Points of convergence between that process and the one in Cork are identified, along with convergences between contemporary traders and the Shawlies. The conclusion sets out my methodological, theoretical and substantive discoveries, and comments on current nostalgic renderings of the Shawlies in Cork’s newly gentrified Corn Market Street.

Factors relating to motivation to change behaviour in individuals who are overweight: application of the health belief model

Background: Obesity is the most important health challenge faced at a global level and represents a rapidly growing problem to the health of populations. Given the escalating global health problem of obesity and its co-morbidities, the need to re-appraise its management is more compelling than ever. The normalisation of obesity within our society and the acceptance of higher body weights have led to individuals being unaware of the reality of their weight status and gravity of this situation. Recognition of the problem is a key component of obesity management and it remains especially crucial to address this issue. A large amount of research has been undertaken on obesity however, limited research has been undertaken using the Health Belief Model. Aim: The aim of the research was to determine factors relating to motivation to change behaviour in individuals who perceive themselves to be overweight and investigate whether the constructs of the Health Belief Model help to explain motivation to change behaviour. Method: The research design was quantitative, correlational and cross-sectional. The design was guided by the Health Belief Model. Data Collection: Data were collected online using a multi-section and multi-item questionnaire, developed from a review of the theoretical and empirical research. Descriptive and inferential statistical analyses were employed to describe relationships between variables. Sample: A sample of 202 men and women who perceived themselves to be overweight participated in the research. Results: Following multivariate regression analysis, perceived barriers to weight loss and perceived benefits of weight loss were significant predictors of motivation to change behaviour. The perceived barriers to weight loss which were significant were psychological barriers to weight loss (p =<0.019) and environmental barriers to physical activity (p=<0.032).The greatest predictor of motivation to change behaviour was the perceived benefits of weight loss (p<0.001). Perceived susceptibility to obesity and perceived severity of obesity did not emerge as significant predictors in this model. Total variance explained by the model was 33.5%. Conclusion: Perceived barriers to weight loss and perceived benefits of weight loss are important determinants of motivation to change behaviour. The current study demonstrated the limited applicability of the Health Belief Model constructs to motivation to change behaviour, as not all core dimensions proved significant predictors of the dependant variable.

First principles simulation of amorphous silicon bulk, interfaces, and nanowires for photovoltaics

Amorphous silicon has become the material of choice for many technologies, with major applications in large area electronics: displays, image sensing and thin film photovoltaic cells. This technology development has occurred because amorphous silicon is a thin film semiconductor that can be deposited on large, low cost substrates using low temperature. In this thesis, classical molecular dynamics and first principles DFT calculations have been performed to generate structural models of amorphous and hydrogenated amorphous silicon and interfaces of amorphous and crystalline silicon, with the ultimate aim of understanding the photovoltaic properties of core-shell crystalline amorphous Si nanowire structures. We have shown, unexpectedly, from the simulations, that our understanding of hydrogenated bulk a-Si needs to be revisited, with our robust finding that when fully saturated with hydrogen, bulk a-Si exhibits a constant optical energy gap, irrespective of the hydrogen concentration in the sample. Unsaturated a-Si:H, with a lower than optimum hydrogen content, shows a smaller optical gap, that increases with hydrogen content until saturation is reached. The mobility gaps obtained from an analysis of the electronic states show similar behavior. We also obtained that the optical and mobility gaps show a volcano curve as the H content is varied from 7% (undersaturation) to 18% (mild oversaturation). In the case of mild over saturation, the mid-gap states arise exclusively from an increase in the density of strained Si-Si bonds. Analysis of our structures shows the extra H atoms in this case form a bridge between neighboring silicon atoms which increases the corresponding Si-Si distance and promotes bond length disorder in the sample. That has the potential to enhance the Staebler-Wronski effect. Planar interface models of amorphous-crystalline silicon have been generated in Si (100), (110) and (111) surfaces. The interface models are characterized by structure, RDF, electronic density of states and optical absorption spectrum. We find that the least stable (100) surface will result in the formation of the thickest amorphous silicon layer, while the most stable (110) surface forms the smallest amorphous region. We calculated for the first time band offsets of a-Si:H/c-Si heterojunctions from first principles and examined the influence of different surface orientations and amorphous layer thickness on the offsets and implications for device performance. The band offsets depend on the amorphous layer thickness and increase with thickness. By controlling the amorphous layer thickness we can potentially optimise the solar cell parameters. Finally, we have successfully generated different amorphous layer thickness of the a-Si/c-Si and a-Si:H/c-Si 5 nm nanowires from heat and quench. We perform structural analysis of the a-Si-/c-Si nanowires. The RDF, Si-Si bond length distributions, and the coordination number distributions of amorphous regions of the nanowires reproduce similar behaviour compared to bulk amorphous silicon. In the final part of this thesis we examine different surface terminating chemical groups, -H, - OH and –NH2 in (001) GeNW. Our work shows that the diameter of Ge nanowires and the nature of surface terminating groups both play a significant role in both the magnitude and the nature of the nanowire band gaps, allowing tuning of the band gap by up to 1.1 eV. We also show for the first time how the nanowire diameter and surface termination shifts the absorption edge in the Ge nanowires to longer wavelengths. Thus, the combination of nanowire diameter and surface chemistry can be effectively utilised to tune the band gaps and thus light absorption properties of small diameter Ge nanowires.

Prophets of the beast: the modernist esotericism of D.H. Lawrence and W.B. Yeats

This thesis analyses the influence of the esoteric tradition on D.H. Lawrence and W.B. Yeats’ thought and examines both authors’ writings in light of the antidemocratic political religions that emerged during and after their respective careers. While a number of extant studies investigate the connection between modernism and the occult and a number of critics have discussed the importance of antidemocratic politics to modernism, this study is unique in its emphasis on the relationship between modernist esotericism and antidemocratic politics, and in its insistence that the interconnection between the two constitutes a fundamental part of both authors’ world-views. This study calls for the development of a multivalent understanding of modernism, which appears as neither a “cultural movement identifiable with bourgeois, capitalist, paternalist, ethnocentrist, phallocentrist, and logocentrist ideologies” (Surette 5) nor entirely the opposite; Romantic, feministic, primitivistic and countercultural. Rather, modernism will be shown to have encompassed both of these ideological orientations, effectively operating on a double front in its crusade to establish a new age. This complexity is visible in both Lawrence and Yeats’ work, as both authors advocate a return to traditional structures while simultaneously endeavouring to usher Western civilisation into a new modern paradigm. Although they primarily grounded their writings in a mythico-pastoral discourse that masked the practical implications of their revolutionary agendas, both authors possessed an attraction to Futurist thought and, albeit rarely, showed an awareness that the change they envisioned could not be brought about without a radical intervention in the political and economic sectors – an intervention that would necessarily take place through the medium of the “machine” from which they were often so adamant to distance themselves. This fusion of technophilic and Arcadian thought-currents – dubbed “archeofuturism” by the French right-wing intellectual Guillaume Faye – constitutes the central focus of this discussion of Lawrentian and Yeatsian thought.

Dry mixing of spice powders - investigation of effect of powder properties on mixture quality of binary powder mixtures

Dry mixing of binary food powders was conducted in a 2L lab-scale paddle mixer. Different types of food powders such as paprika, oregano, black pepper, onion powder and salt were used for the studies. A novel method based on a digital colour imaging system (DCI) was developed to measure the mixture quality (MQ) of binary food powder mixtures. The salt conductivity method was also used as an alternative method to measure the MQ. In the first part of the study the DCI method was developed and it showed potential for assessing MQ of binary powder mixes provided there was huge colour difference between the powders. In the second and third part of the study the effect of composition, water content, particle size and bulk density on MQ was studied. Flowability of powders at various moisture contents was also investigated. The mixing behaviour was assessed using coefficient of variation. Results showed that water content and composition influence the mixing behavior of powders. Good mixing was observed up to size ratios of 4.45 and at higher ratios MQ disimproved. The bulk density had a larger influence on the MQ. In the final study the MQ evaluation of binary and ternary powder mixtures was compared by using two methods – salt conductivity method and DCI method. Two binary food and two quaternary food powder mixtures with different coloured ingredients were studied. Overall results showed that DCI method has a potential for use by industries and it can analyse powder mixtures with components that have differences in colour and that are not segregating in nature.

Prostate cancer treatment as an embodied rite of passage: impotence and incontinence as challenges to status reversal and reintegration

Introduction and Rationale: A central argument in the thesis is that performative acts of control, sexual potency and spontaneity are central to the continuous construction of embodied masculine identities. The acts of control, and particularly issues of spontaneity, are central to understandings and addressing the difficulties men face at varying levels of embodied identity. Using Watson’s (2000) ‘Male body schema’, I will explore the challenges and opportunities men face when negotiating normative, pragmatic, and experiential embodiment. I will later then explore the importance of these levels of embodiment to achieving visceral embodiment; or what I would define as a renewed unconscious satisfaction and ability to achieve and maintain normative, pragmatic and experiential forms of embodiment. Purpose and Objectives: Using the concept of liminality, and permanent liminality, the thesis explores how we can interpret and understand men’s experience of prostate cancer diagnosis and treatment, and their struggle to regain power and control in the context of diagnosis, and also the side effects to treatment. The strategies men adopt in seeking out personalised medical programmes of treatment with their doctors are explored in detail. The power and control that can be exercised over medical professionals and treatment options is demonstrated. Method: Collecting responses online from prostate specific discussion boards via gatekeepers, and from interviews on the ‘health talk’ online database, three intersecting conceptual categories - liminality, masculinity and the body/embodiment - are combined in this research. Liminality and ‘time’ are directly linked to notions of ‘success’ and ‘outcome’ during the treatment process, and mark distinct points at which men, and their families, expect measures or limits to have been reached. Exploring liminality within the context of Turner’s ‘rites of passage’, I explore the difficulty men face in concluding the third stage of the rites; reintegration. Results: Prostate cancer diagnosis and treatment, impotence and incontinence, in particular, have profound implications for the continuous construction of embodied masculine identities, and thus identity in general, making the construction of hegemonic ideals in the context of a highly ‘performative’ society highly troublesome. The issue of ‘spontaneity’ in the construction of various forms of embodied identities is of particular concern for men who contributed to this study.

Infant milk formula manufacture: process and compositional interactions in high dry matter wet-mixes

Infant milk formula (IMF) is fortified milk with composition based on the nutrient content in human mother's milk, 0 to 6 months postpartum. Extensive medical and clinical research has led to advances in the nutritional quality of infant formula; however, relatively few studies have focused on interactions between nutrients and the manufacturing process. The objective of this research was to investigate the impact of composition and processing parameters on physical behaviour of high dry matter (DM) IMF systems with a view to designing more sustainable manufacturing processes. The study showed that commercial IMF, with similar compositions, manufactured by different processes, had markedly different physical properties in dehydrated or reconstituted state. Commercial products made with hydrolysed protein were more heat stable compared to products made with intact protein, however, emulsion quality was compromised. Heat-induced denaturation of whey proteins resulted in increased viscosity of wet-mixes, an effect that was dependant on both whey concentration and interactions with lactose and caseins. Expanding on fundamental laboratory studies, a novel high velocity steam injection process was developed whereby high DM (60%) wet-mixes with lower denaturation/viscosity compared to conventional processes could be achieved; powders produced using this process were of similar quality to those manufactured conventionally. Hydrolysed proteins were also shown to be an effective way of reducing viscosity in heat-treated high DM wet-mixes. In particular, using a whey protein concentrate whereby β-Lactoglobulin was selectively hydrolysed, i.e., α-Lactalbumin remained intact, reduced viscosity of wet-mixes during processing while still providing good emulsification. The thesis provides new insights into interactions between nutrients and/or processing which influence physical stability of IMF both in concentrated liquid and powdered form. The outcomes of the work have applications in such areas as; increasing the DM content of spray drier feeds in order to save energy, and, controlling final powder quality.

Highly sensitive surface enhanced Raman scattering (SERS) detection platforms formed by large area self-assembled Au nanorod arrays

This thesis explores a new method to fabricate SERS detection platforms formed by large area self-assembled Au nanorod arrays. For the fabrication of these new SERS platforms a new droplet deposition method for the self-assembly of Au nanorods was developed. The method, based in the controlled evaporation of organic suspensions of Au nanorods, was used for the fabrication of horizontal and vertical arrays of Au nanorods over large areas (100μm2). The fabricated nanorods arrays showed a high degree of order measured by SEM and optical microscopy over mm2 areas, but unfortunately they detached from the support when immersed in any analyte solutions. In order to improve adhesion of arrays to the support and clean off residual organic matter, we introduced an additional stamping process. The stamping process allows the immobilization of the arrays on different flexible and rigid substrates, whose feasibility as SERS platforms were tested satisfactory with the model molecule 4ABT. Following the feasibility study, the substrates were used for the detection of the food contaminant Crystal Violet and the drug analogue Benzocaine as examples of recognition of health menaces in real field applications.

Manipulation of magnetic anisotropy in nanostructures

Of late, the magnetic properties of micro/nano-structures have attracted intense research interest both fundamentally and technologically particularly to address the question that how the manipulation in the different layers of nanostructures, geometry of a patterned structure can affect the overall magnetic properties, while generating novel applications such as in magnetic sensors, storage devices, integrated inductive components and spintronic devices. Depending on the applications, materials with high, medium or low magnetic anisotropy and their possible manipulation are required. The most dramatic manifestation in this respect is the chance to manipulate the magnetic anisotropy over the intrinsic preferential direction of the magnetization, which can open up more functionality particularly for device applications. Types of magnetic anisotropies of different nanostructured materials and their manipulation techniques are investigated in this work. Detail experimental methods for the quantitative determination of magnetic anisotropy in nanomodulated Ni45Fe55 thin film are studied. Magnetic field induced in-plane rotations within the nanomodulated Ni45Fe55 continuous films revealed various rotational symmetries of magnetic anisotropy due to dipolar interactions showing a crossover from lower to higher fold of symmetry as a function of modulation geometry. In a second approach, the control of exchange anisotropy at ferromagnetic (FM) – aniferomagnetic (AFM) interface in multifferoic nanocomposite materials, where two different phase/types of materials were simultaneously synthesized, was investigated. The third part of this work was to study the electroplated thin films of metal alloy nanocomposite for enhanced exchange anisotropy. In this work a unique observation of an anti-clock wise as well as a clock wise hysteresis loop formation in the Ni,Fe solid solution with very low coercivity and large positive exchange anisotropy/exchange bias have been investigated. Hence, controllable positive and negative exchange anisotropy has been observed for the first time which has high potential applications such as in MRAM devices.

The role of structure in the electrochemical performance of nanostructured metal oxides for lithium ion battery anodes

The Li-ion battery has for a number of years been a key factor that has enabled an ever increasing number of modern consumer devices, while in recent years has also been sought to power a range of emerging electric and hybrid electric vehicles. Due to their importance and popularity, a number of characteristics of Li-ion batteries have been subjected to intense work aimed at radical improvement. Although electrode material selection intrinsically defines characteristics like maximum capacity or voltage, engineering of the electrode structure may yield significant improvements to the lifetime performance of the battery, which would not be available if the material was used in its bulk form. The body of work presented in this thesis describes the relationship between the structure of electrochemically active materials and the course of the electrochemical processes occurring within the electrode. Chapter one describes the motivation behind the research presented herein. Chapter two serves to highlight a number of key advancements which have been made and detailed in the literature over recent years, pertaining to the use of nanostructured materials in Li-ion technology. Chapter three details methods and techniques applied in developing the body of work presented in this thesis. Chapter four details structural, molecular and electrochemical characteristics of tin oxide nanoparticle based electrodes, with particular emphasis on the relationship between the size distribution and the electrode performance. Chapter five presents findings of structural, electrochemical and optical study of indium oxide nanoparticles grown on silicon by molecular beam epitaxy. In chapter 6, tin oxide inverted opal electrodes are investigated for the conduct of the electrochemical performance of the electrodes under varying rate of change of potential. Chapter 7 presents the overall conclusions drawn from the results presented in this thesis, coupled with an indication of potential future work which may be explored further.

Physical function, psychosocial adaptation, and hardiness post stroke

Introduction: Stroke is a chronic condition that significantly impacts on morbidity and mortality (Balanda et al. 2010). Globally, the complexity of stroke is well documented and more recently, in Ireland, as part of the National Survey of Stroke Survivors (Horgan et al. 2014). There are a number of factors that are known to influence adaptation post stroke. However, there is a lack of research to explain the variability in how survivors adapt post stroke. Hardiness is a broad personality trait that leads to better outcome. This study investigated the influence of hardiness and physical function on psychosocial adaptation post stroke. Methods: A quantitative cross-sectional, correlational, exploratory study was conducted between April and November 2013. The sample consisted of stroke survivors (n=100) who were recruited from three hospital outpatient departments and completed a questionnaire package. Results: The mean age of participants was 76 years (range 70-80), over half (56%) of the participants achieved the maximum score of 20 on the Barthel Index indicating independence in activities of daily living. The median number of days since stroke onset was 91 days (range 74-128). The total mean score and standard deviation for hardiness was 1.89 (0.4) as measured by the Dispositional Resilience Scale, indicating medium hardiness (possible range 0-3). Psychosocial adaptation was measured using the Psychosocial Adjustment to Illness Scale, the total weighted mean and standard deviation was 0.54 (0.3) indicating a satisfactory level of psychosocial adaptation (possible range 0-3). A hierarchical multiple linear regression was performed which contained 6 independent variables (hardiness, living arrangement, and length of hospital stay, number of days since stroke onset, physical function and self-rated recovery). Findings demonstrated that physical function (p<0.001) and hardiness (p=0.008) were significantly related to psychosocial adaptation. Altogether, 65% of the variation in psychosocial adaptation can be explained by the combined effect of the independent variables. Physical functioning had the highest unique contribution (11%) to explain the variance in psychosocial adaptation while self-rated recovery, hardiness, and living arrangements contributed 3% each. Conclusion: This research provides important information regarding factors that influence psychosocial adaptation post stroke at 3 months. Physical function significantly contributed to psychosocial adaptation post stroke. The personality trait of hardiness provides insight into how behaviour influenced adaptation post stroke. While hardiness also had a strong relationship with psychosocial adaptation, further research is necessary to fully comprehend this process.

Metabolism of host-derived carbohydrates by Bifidobacterium breve UCC2003

Bifidobacteria are Gram positive, anaerobic, typically Y-shaped bacteria which are naturally found in the digestive tract of certain mammals, birds and insects. Bifidobacterium breve strains are numerically prevalent among the gut microbiota of many healthy breast-fed infants. The prototypical B. breve strain UCC2003 has previously been shown to utilise numerous carbohydrates of plant origin. Various aspects of host-derived carbohydrate metabolism occurring in this bacterium will be described in this thesis. Chapter II describes B. breve UCC2003 utilisation of sialic acid, a nine-carbon monosaccharide, which is found in human milk oligosaccharides (HMOs) and the mucin glycoprotein. B. breve UCC2003 was also shown to cross-feed on sialic acid released from 3’ sialyllactose, a prominent HMO, by the extracellular sialidase activity of Bifidobacterium bifidum PRL2010. Chapter III reports on the transcriptional regulation of sialic acid metabolism in B. breve UCC2003 by a transcriptional repressor encoded by the nanR gene. NanR belongs to the GntR-family of transcriptional regulators and represents the first bifidobacterial member of this family to be characterised. Chapter IV investigates B. breve UCC2003 utilisation of mucin. B. breve UCC2003 was shown to be incapable of degrading mucin; however when grown in co-culture with B. bifidum PRL2010 it exhibits enhanced growth and survival properties. A number of methods were used to investigate and identify the mucin components supporting this enhanced growth/viability phenotype. Chapter V describes the characterisation of two sulfatase-encoding gene clusters from B. breve UCC2003. The transcriptional regulation of both sulfatase-encoding gene clusters was also investigated. The work presented in this thesis represents new information on the metabolism of host-derived carbohydrates in bifidobacteria, thus increasing our understanding of how these gut commensals are able to colonise and persist in the gastrointestinal tract.

Diphtheria, the public health response and the origins of the childhood immunisation programme in Ireland

In common with most countries, the childhood immunisation programme in Ireland was founded on a successful public health response to diphtheria. The success of the antidiphtheria public health intervention in Ireland has meant that no case of the disease has been recorded in the state for almost fifty years. This is a significant achievement considering that diphtheria continues to appear annually in many European states, albeit in much reduced numbers on former years. For parents and children of nineteenth, and early twentieth-century Ireland, diphtheria represented the ‘most dreaded disease of childhood’, however, for their modern day counterparts diphtheria is no more than an obscure disease mentioned in leaflets promoting the benefits of childhood immunisation. In Ireland, diphtheria has been consigned to history, and so too have the horrors and mass fatalities once associated with it. But how was this achieved? Was active immunisation received with open arms by public health authorities, the wider medical community, and the general public? This study tackles these questions by undertaking the first historical examination of the issues which underpin the origins of active immunisation in Ireland. It explores the driving forces that shaped the national childhood immunisation programme, and those that opposed them. In addition, it examines the complex social implications attendant on the introduction of this mass public health intervention in an Irish context.

Characterisation of the role of Fas in intestinal inflammation and cancer

Background: The role of Fas (CD95) and its ligand, Fas ligand (FasL/CD95L), is poorly understood in the intestine. Whilst Fas is best studies in terms of its function in apoptosis, recent studies suggest that Fas ligation may mediate additional, non-apoptotic functions such as inflammation. Toll like Receptors (TLRs) play an important role in mediating inflammation and homeostasis in the intestine. Recent studies have shown that a level of crosstalk exists between the Fas and TLR signalling pathways but this has not yet been investigated in the intestine. Aim: The aim of this study was to evaluate potential cross-talk between TLRs and Fas/FasL system in intestinal cancer cells. Results: Treatment with TLR4 and TLR5 ligands, but not ligands for TLR2 and TLR9 increased the expression of Fas and FasL in intestinal cancer cells in vitro. Consistent with this, expression of Fas and FasL was reduced in the distal colon tissue from germ-free (GF), TLR4 and TLR5 knock-out (KO) mice but was unchanged in TLR2KO tissue, suggesting that intestinal cancer cells display a degree of specificity in their ability to upregulate Fas and FasL expression in response to TLR ligation. Expression of both Fas and FasL was significantly reduced in TRIF KO tissue, indicating that signalling via TRIF by TLR4 and TLR5 agonists may be responsible for the induction of Fas and FasL expression in intestinal cancer cells. In addition, modulating Fas signalling using agonistic anti-Fas augmented TLR4 and TLR5-mediated tumour necrosis factor alpha (TNFα) and interleukin 8 (IL)-8 production by intestinal cancer cells, suggesting crosstalk occurs between these receptors in these cells. Furthermore, suppression of Fas in intestinal cancer cells reduced the ability of the intestinal pathogens, Salmonella typhimurium and Listeria monocytogenes to induce the expression of IL-8, suggesting that Fas signalling may play a role in intestinal host defence against pathogens. Inflammation is known to be important in colon tumourigenesis and Fas signalling on intestinal cancer cells has been shown to result in the production of inflammatory mediators. Fas-mediated signalling may therefore play a role in colon cancer development. Suppression of tumour-derived Fas by 85% led to a reduction in the tumour volume and changes in tumour infiltrating macrophages and neutrophils. TLR4 signalling has been shown to play a role in colon cancer via the recruitment and activation of alternatively activated immune cells. Given the crosstalk seen between Fas and TLR4 signalling in intestinal cancer cells in vitro, suppressing Fas signalling may enhance the efficacy of TLR4 antagonism in vivo. TLR4 antagonism resulted in smaller tumours with fewer infiltrating neutrophils. Whilst Fas downregulation did not significantly augment the ability of TLR4 antagonism to reduce the final tumour volume, Fas suppression may augment the anti-tumour effects of TLR4 antagonism as neutrophil infiltration was further reduced upon combinatorial treatment. Conclusion: Together, this study demonstrates evidence of a new role for Fas in the intestinal immune response and that manipulating Fas signalling has potential anti-tumour benefit.