Cell migration and proliferation on homogeneous and non-homogeneous domains : modelling on the scale of individuals and populations

Cell migration is a behaviour critical to many key biological effects, including wound healing, cancerous cell invasion and morphogenesis, the development of an organism from an embryo. However, given that each of these situations is distinctly different and cells are extremely complicated biological objects, interest lies in more basic experiments which seek to remove conflating factors and present a less complex environment within which cell migration can be experimentally examined. These include in vitro studies like the scratch assay or circle migration assay, and ex vivo studies like the colonisation of the hindgut by neural crest cells. The reduced complexity of these experiments also makes them much more enticing as problems to mathematically model, like done here. The primary goal of the mathematical models used in this thesis is to shed light on which cellular behaviours work to generate the travelling waves of invasion observed in these experiments, and to explore how variations in these behaviours can potentially predict differences in this invasive pattern which are experimentally observed when cell types or chemical environment are changed. Relevant literature has already identified the difficulty of distinguishing between these behaviours when using traditional mathematical biology techniques operating on a macroscopic scale, and so here a sophisticated individual-cell-level model, an extension of the Cellular Potts Model (CPM), is been constructed and used to model a scratch assay experiment. This model includes a novel mechanism for dealing with cell proliferations that allowed for the differing properties of quiescent and proliferative cells to be implemented into their behaviour. This model is considered both for its predictive power and used to make comparisons with the travelling waves which result in more traditional macroscopic simulations. These comparisons demonstrate a surprising amount of agreement between the two modelling frameworks, and suggest further novel modifications to the CPM that would allow it to better model cell migration. Considerations of the model’s behaviour are used to argue that the dominant effect governing cell migration (random motility or signal-driven taxis) likely depends on the sort of invasion demonstrated by cells, as easily seen by microscopic photography. Additionally, a scratch assay simulated on a non-homogeneous domain consisting of a ’fast’ and ’slow’ region is also used to further differentiate between these different potential cell motility behaviours. A heterogeneous domain is a novel situation which has not been considered mathematically in this context, nor has it been constructed experimentally to the best of the candidate’s knowledge. Thus this problem serves as a thought experiment used to test the conclusions arising from the simulations on homogeneous domains, and to suggest what might be observed should this non-homogeneous assay situation be experimentally realised. Non-intuitive cell invasion patterns are predicted for diffusely-invading cells which respond to a cell-consumed signal or nutrient, contrasted with rather expected behaviour in the case of random-motility-driven invasion. The potential experimental observation of these behaviours is demonstrated by the individual-cell-level model used in this thesis, which does agree with the PDE model in predicting these unexpected invasion patterns. In the interest of examining such a case of a non-homogeneous domain experimentally, some brief suggestion is made as to how this could be achieved.

Reliability and validity of conjunctival ultraviolet autofluorescence measurement

BACKGROUND: Conjunctival ultraviolet autofluorescence (UVAF) photography was developed to detect and characterise pre-clinical sunlight-induced UV damage. The reliability of this measurement and its relationship to outdoor activity are currently unknown. METHODS: 599 people aged 16-85 years in the cross-sectional Norfolk Island Eye Study were included in the validation study. 196 UVAF individual photographs (49 people) and 60 UVAF photographs (15 people) of Norfolk Island Eye Study participants were used for intra- and inter-observer reliability assessment, respectively. Conjunctival UVAF was measured using UV photography. UVAF area was calculated using computerised methods by one grader on two occasions (intra-observer analysis) or two graders (inter-observer analysis). Outdoor activity category, during summer and winter separately, was determined with a UV questionnaire. Total UVAF equalled the area measured in four conjunctival areas (nasal/temporal conjunctiva of right and left eyes). RESULTS: Intra-observer (ρ_c=0.988, 95% CI 0.967 to 0.996, p<0.001), and inter-observer concordance correlation coefficients (ρ_c=0.924, 95% CI 0.870 to 0.956, p<0.001) of total UVAF exceeded 0.900. When grouped according to 10 mm(2) total UVAF increments, intra- and inter-observer reliability was very good (κ=0.81) and good (κ=0.71), respectively. Increasing time outdoors was strongly with increasing total UVAF in summer and winter (p(trend) <0.001). CONCLUSION: Intra- and inter-observer reliability of conjunctival UVAF is high. In this population, UVAF correlates strongly with the authors' survey-based assessment of time spent outdoors.

The Norfolk Island Eye Study (NIES) : rationale, methodology and distribution of ocular biometry (Biometry of the Bounty)

Aim: To describe the recruitment, ophthalmic examination methods and distribution of ocular biometry of participants in the Norfolk Island Eye Study, who were individuals descended from the English Bounty mutineers and their Polynesian wives. Methods: All 1,275 permanent residents of Norfolk Island aged over 15 years were invited to participate, including 602 individuals involved in a 2001 cardiovascular disease study. Participants completed a detailed questionnaire and underwent a comprehensive eye assessment including stereo disc and retinal photography, ocular coherence topography and conjunctival autofluorescence assessment. Additionally, blood or saliva was taken for DNA testing. Results: 781 participants aged over 15 years were seen (54% female), comprising 61% of the permanent Island population. 343 people (43.9%) could trace their family history to the Pitcairn Islanders (Norfolk Island Pitcairn Pedigree). Mean anterior chamber depth was 3.32mm, mean axial length (AL) was 23.5mm, and mean central corneal thickness was 546 microns. There were no statistically significant differences in these characteristics between persons with and without Pitcairn Island ancestry. Mean intra-ocular pressure was lower in people with Pitcairn Island ancestry: 15.89mmHg compared to those without Pitcairn Island ancestry 16.49mmHg (P = .007). The mean keratometry value was lower in people with Pitcairn Island ancestry (43.22 vs. 43.52, P = .007). The corneas were flatter in people of Pitcairn ancestry but there was no corresponding difference in AL or refraction. Conclusion: Our study population is highly representative of the permanent population of Norfolk Island. Ocular biometry was similar to that of other white populations. Heritability estimates, linkage analysis and genome-wide studies will further elucidate the genetic determinants of chronic ocular diseases in this genetic isolate.

The remediation of the personal photograph and the politics of self-representation in digital storytelling

Over the past couple of decades, the cultural field formerly known as ‘domestic’, and later ‘personal’ photography has been remediated and transformed as part of the social web, with its convergence of personal expression, interpersonal communication, and online social networks (most recently via platforms like Flickr, Facebook and Twitter). Meanwhile, the Digital Storytelling movement (involving the workshop-based production of short autobiographical videos) from its beginnings in the mid 1990s relied heavily on the narrative power of the personal photograph, often sourced from family albums, and later from online archives. This paper addresses the new issues arising for the politics of self-representation and personal photography in the era of social media, focusing particularly on the consequences of online image-sharing. It discusses in detail the practices of selection, curation, manipulation and editing of personal photographic images among a group of activist-oriented queer digital storytellers who have in common a stated desire to share their personal stories in pursuit of social change, and whose stories often aim to address both intimate and antagonistic publics.

Looking into the light : reinventing the apparatus in contemporary art

Technical images such as photography, film and video, are dependent on apparatuses for their production and dissemination, yet the apparatus itself is often hidden or obscured in the experience of the work and the discourse that surrounds it. This practice-led research identifies key practice strategies to foreground the apparatus both in the production of work and in its presentation. It therefore develops critical and generative strategies to explore and interrogate the workings of the 'apparatus-audience complex,' and the particular modes of spectatorship that this entails.

In the shadow of the enlightenment : Le Corbusier, Le Faisceau and Georges Valois

On 9 January 1927 Le Corbusier materialised on the front cover of the Faisceau journal edited by Georges Valois Le Nouveau Siècle which printed the single-point perspective of Le Corbusier’s Plan Voisin and an extract from the architect’s discourse in Urbanisme. In May Le Corbusier presented slides of his urban designs at a fascist rally. These facts have been known ever since the late 1980s when studies emerged in art history that situated Le Corbusier’s philosophy in relation to the birth of twentieth-century fascism in France—an elision in the dominant reading of Le Corbusier’s philosophy, as a project of social utopianism, whose received genealogy is Saint-Simon and Charles Fourier. Le Corbusier participated with the first group in France to call itself fascist, Valois’s militant Faisceau des Combattants et Producteurs, the “Blue Shirts,” inspired by the Italian “Fasci” of Mussolini. Thanks to Mark Antliff, we know the Faisceau did not misappropriate Le Corbusier’s plans, in some remote quasi-symbolic sense, rather Valois’s organisation was premised on the redesign of Paris based on Le Corbusier’s schematic designs. Le Corbusier’s Urbanisme was considered the “prodigious” model for the fascist state Valois called La Cité Française – after his mentor the anarcho-syndicalist Georges Sorel. Valois stated that Le Corbusier’s architectural concepts were “an expression of our profoundest thoughts,” the Faisceau, who “saw their own thought materialized” on the pages of Le Corbusier’s plans. The question I pose is, In what sense is Le Corbusier’s plan a complete representation of La Cité? For Valois, the fascist city “represents the collective will of La Cité” invoking Enlightenment philosophy, operative in Sorel, namely Rousseau, for whom the notion of “collective will” is linked to the idea of political representation: to ‘stand in’ for someone or a group of subjects i.e. the majority vote. The figures in Voisin are not empty abstractions but the result of “the will” of the “combatant-producers” who build the town. Yet, the paradox in anarcho-syndicalist anti-enlightenment thought – and one that became a problem for Le Corbusier – is precisely that of authority and representation. In Le Corbusier’s plan, the “morality of the producers” and “the master” (the transcendent authority that hovers above La Cité) is lattened into a single picture plane, thereby abolishing representation. I argue that La Cité pushed to the limits of formal abstraction by Le Corbusier thereby reverts to the Enlightenment myth it first opposed, what Theodor Adorno would call the dialectic of enlightenment.

In-side-out : photojournalists from community and mainstream media organisations in Brazil's favelas

New media initiatives in Brazil's capital, Rio de Janeiro, are attempting to change mainstream ideas about favelas (poor districts) and their inhabitants. This thesis focuses on two of these initiatives that are being run by non-government organisations, Viva Favela and Imagens do Povo. This study takes an ethnographic and discursive approach to investigating and comparing two categories of professional photographers to determine how their working practices contribute to empowering the people living in Brazil's favelas. While mainstream photojournalists mainly cover human rights abuses in the favelas, community photographers challenge stereotypes by presenting images of the favelas' everyday life.

WATER - a series of photographs by Louise Grayson

This body of photographic work has been created to firstly, explore a new approach to practice-led research that uses an “action genre” approach to reflective practice (Lemke) and secondly, to visually explore human interaction with the fundamental item in life - water. The first of these is based on the contention that to understand the meanings inherent in photographs we cannot look merely at the end result. It is essential to keep looking at the actions of practitioners, and the influences upon them, to determine how external influences affect the meaning potential of editorial photographs (Grayson, 2012). WATER therefore, provides an ideal platform to reflect upon the actions and influences involved in creating work within the photographic genre of photojournalism. It enables this practitioner to reflect on each stage of production to gain a better understanding of how external influences impact the narrative potential within images created. There are multi-faceted influences experienced by photographers who are creating images that, in turn, are part of constructing and presenting the narrative potential of editorial photographs. There is an important relationship between professional photographers and the technical, cultural, economic and institutional forces that impinge upon all stages of production and publication. What results is a greater understanding of technical, cultural, economic and institutional forces that impinge upon all stages of production and publication. Therefore, to understand the meanings inherent in photographs within WATER, I do not look merely at the end result. It provides a case study looking at my actions in the filed, and the influences upon me, to determine how external influences affect the meaning potential of these photographs (Grayson, 2012). As a result, this project adds to the body of scholarship around the definition of Photojournalism, how it has adapted to the current media environment and provides scope for further research into emerging new genres within editorial photography, such as citizen photojournalism. Concurrently, the photographs themselves were created to visually explore how there remains a humanistic desire to interact with the natural form of water even while living a modern cosmopolitan life around it. Taking a photojournalistic approach to exploring this phenomenon, the images were created by “capturing moments as they happened” with no posing or setting up of images. This serendipitous approach to the photographic medium provides the practitioner with at least an attempt to direct the subjectivity contained explicitly in photographs. What results is a series of images that extend the visual dialogue around the role of water within modern humanistic lifestyles and how it remains an integral part of our society’s behaviors. It captures important moments that document this relationship at this time of modern development. The resulting works were exhibited and published as part of the Head On Photo Festival, Australia's largest photo festival and the world's second largest festival in Sydney 20-24 May 2013. The WATER series of images were curated by three Magnum members; Ian Berry, Eli Reed and Chris Steele-Perkins. Magnum is a highly regarded international photographic co-operative with editorial offices in New York, London, Paris and Tokyo. There was a projection of the works as part of the official festival programme, presented to both members of the public and Sydney’s photography professionals. In addition, a sample of images from the WATER series was chosen for inclusion in the Magnum-published hardcover book. References Grayson, Louise. 2012. “Editorial photographs and patterns of practice.” Journalism Practice. Accessed: http://www.tandfonline.com/doi/abs/10.1080/17512786.2012.726836#.UbZN-L--1RQ Lemke, Jay. 1995. Textual Politics: Discourse and Social Dynamics. London: Taylor & Francis.

Queensland small towns Documentary project

This photographic documentary project explores diverse stories of Queensland mining towns. Images compare the interplay between communities, commerce and natural resources. The project is a collaboration between three Brisbane universities (Queensland University of Technology, Griffith University and University of Queensland) and is supported by the Brisbane Powerhouse and the State Library of Queensland. Funded by a $50,000 Arts Queensland grant.

The evaluation of a clinical scar scale for porcine burn scars

This study describes the evaluation of a clinical scar scale for our porcine burn scars, which includes scar cosmetic outcome, colour, height and hair, supplemented with reference porcine scar photographs representing each scar outcome and scar colour scores. A total of 72 porcine burn scars at week 6 after burn were rated in vivo and/or on photographs. Good agreements were achieved for both intra-rater reliability (correlation is 0.86-0.98) and inter-rater reliability (ICC=80-85%). The results showed statistically significant correlations for each pair in this clinical scar scale (p<0.01), with the best correlation found between scar cosmetic outcome and scar colour. A multivariate principle components analysis revealed that this clinical scar assessment was highly correlated with scar histology, wound size, and re-epithelialisation data (p<0.001). More severe scars are clinically characterised by darker purple colouration, more elevation, no presence of hair, histologically by thicker scar tissue, thinner remaining normal dermis, are more likely to have worse contraction, and slower re-epithelialisation. This study demonstrates that our clinical scar scale is a reliable, independent and valuable tool for assessing porcine burn outcome and truthfully reflects scar appearance and function. To our knowledge, this is the first study demonstrating a high correlation between clinical scar assessment and scar histology, wound contraction and re-epithelialisation data on porcine burn scars. We believe that the successful use of porcine scar scales is invaluable for assessing potential human burn treatments.

Social and cultural borders in Rio de Janeiro : the everyday life of community and mainstream photojournalists

This paper takes a multimethod approach which combines ethnographic techniques and discourse studies to investigate two contrasting professional groups: community photographers, who are favela dwellers who have developed photographic projects in Brazil‘s favelas, and photojournalists of the mainstream media. Its purpose is to determine how a cultural and social divide in the city of Rio de Janeiro shapes both community photographers and mainstream photojournalists’ practices, discourses, and identities. While community photographers strive to establish a humane and positive view about favelas and their residents by shifting the focus from poverty, shortages, violence, and criminality to images of the ordinary life, mainstream photojournalists express the view that their role is of primary importance for the defence of human rights in the favelas by helping to prevent, for instance, police abuses and violations. As the data analysis indicated the existence of socio-spatial borders all over Rio de Janeiro, this study adopted the idea of a divided city without denying interconnections between favelas and the city’s political life. Through the analysis of categories which emerged from the data, the complex world of documenting favela life is explored. The major themes touched upon are: the breakdown between the mainstream media and the favela communities; the different kinds of relationships which arise in Rio’s low income suburbs; and the gradual return of mainstream news workers to favelas.

Business Innovation and Disruption in Publishing

This is the first volume in a book series examining how organizations in the creative industries respond to disruptive change and how they themselves generate business innovations. The aspiration of this book series is to understand some of the common forces behind the disruptions occurring in so many creative industries today and identifying the most promising strategies and responses by organizations to create new value propositions, business models and business practices that can enable these industry participants to cope with and eventually thrive as their industries and sectors are transformed. The chapters included in the volume examine the processes of disruption and transformation due to the technology of the Internet, social forces driven by social media, the development of new portable digital devices with greater capabilities and smaller size, the decreasing costs of new information, and the creation of new business models and forms of intellectual property ownership rights for a digitized industry. The context for this volume is the publishing industries, understood as the industries for the publishing of fiction and non-fiction books, academic literature, consumer as well as trade magazines, and daily newspapers. This volume includes chapters by an internationally diverse array of media scholars whose chapters provide insights into these phenomena in Eastern Europe, Finland, France, Germany, Norway, Portugal, Russia, and the United States, using different methodological frameworks including, but not limited to, surveys, in-depth interviews and multiple-case studies. One gap that this book series seeks to fill is that between the study of business innovation and disruption by innovation scholars largely based in business school settings and similar studies by scholarly experts from non-business school disciplines, including the broader social sciences (e.g. sociology, political science, economic geography) and creative industry based professional school disciplines (e.g. architecture, communications, design, film making, journalism, media studies, performing arts, photography and television). Future volumes of this book series will examine disruption and business innovation in the film, video and photography sectors (volume two), the music sector (volume three) and interactive entertainment (volume four), with subsequent volumes focusing on the most relevant developments in creative industry business innovation and disruption that emerge.