Nancy Spero: pain and politics, 1966-1976

The ten-year period that started with Nancy Spero’s War Series (1966-70) and ended with the completion of Torture of Women (1974-6) were of vital importance to the development of this key figure of feminist art. This was the moment when Spero turned her focus to politics, departing from a practice that was concerned with personal disaffection, instead focusing on profoundly social concerns. Essential to this evolution is a focus on pain. From the War Series through the Artaud Paintings (1970-71), Codex Artaud (1971-2), and Torture of Women, pain, both internal and external, was imagined in multiple forms. In Spero’s explorations of the theme, pain becomes metaphoric of the experience of women living under patriarchy, an amorphous but still profoundly disabling sensation that attacks both body and mind. This thesis explores Spero’s use of physical pain during moment of feminist art’s emergence, seeing it as a political metaphor for the way in which patriarchy invisibly controls and undermines women. Framed broadly by the question of art's relationship with politics during this turbulent period of anti-war and feminist activism, this thesis closely examines the way in which an analogy to pain figures the body in the work in complex terms, pursuing an ideological ambition through recourse to feeling.

Modifying germanium nanowires for future devices: an in situ TEM study

Germanium was of great interest in the 1950’s when it was used for the first transistor device. However, due to the water soluble and unstable oxide it was surpassed by silicon. Today, as device dimensions are shrinking the silicon oxide is no longer suitable due to gate leakage and other low-κ dielectrics such as Al2O3 and HfO2 are being used. Germanium (Ge) is a promising material to replace or integrate with silicon (Si) to continue the trend of Moore’s law. Germanium has better intrinsic mobilities than silicon and is also silicon fab compatible so it would be an ideal material choice to integrate into silicon-based technologies. The progression towards nanoelectronics requires a lot of in depth studies. Dynamic TEM studies allow observations of reactions to allow a better understanding of mechanisms and how an external stimulus may affect a material/structure. This thesis details in situ TEM experiments to investigate some essential processes for germanium nanowire (NW) integration into nanoelectronic devices; i.e. doping and Ohmic contact formation. Chapter 1 reviews recent advances in dynamic TEM studies on semiconductor (namely silicon and germanium) nanostructures. The areas included are nanowire/crystal growth, germanide/silicide formation, irradiation, electrical biasing, batteries and strain. Chapter 2 details the study of ion irradiation and the damage incurred in germanium nanowires. An experimental set-up is described to allow for concurrent observation in the TEM of a nanowire following sequential ion implantation steps. Grown nanowires were deposited on a FIB labelled SiN membrane grid which facilitated HRTEM imaging and facile navigation to a specific nanowire. Cross sections of irradiated nanowires were also performed to evaluate the damage across the nanowire diameter. Experiments were conducted at 30 kV and 5 kV ion energies to study the effect of beam energy on nanowires of varied diameters. The results on nanowires were also compared to the damage profile in bulk germanium with both 30 kV and 5 kV ion beam energies. Chapter 3 extends the work from chapter 2 whereby nanowires are annealed post ion irradiation. In situ thermal annealing experiments were conducted to observe the recrystallization of the nanowires. A method to promote solid phase epitaxial growth is investigated by irradiating only small areas of a nanowire to maintain a seed from which the epitaxial growth can initiate. It was also found that strain in the nanowire greatly effects defect formation and random nucleation and growth. To obtain full recovery of the crystal structure of a nanowire, a stable support which reduces strain in the nanowire is essential as well as containing a seed from which solid phase epitaxial growth can initiate. Chapter 4 details the study of nickel germanide formation in germanium nanostructures. Rows of EBL (electron beam lithography) defined Ni-capped germanium nanopillars were extracted in FIB cross sections and annealed in situ to observe the germanide formation. Chapter 5 summarizes the key conclusions of each chapter and discusses an outlook on the future of germanium nanowire studies to facilitate their future incorporation into nanodevices.

Elizabeth Bowen and the art of visuality

This thesis is the first sustained assessment of Elizabeth Bowen’s writing from a visual perspective. By first compiling a visual biography of the author, I argue that Bowen’s responsiveness to art, her relationships with artists, and her knowledge of modern and traditional aesthetics are formative influences on her work. Investigating her assertion that she was a “visual writer,” my discussion develops into an examination of her technique of “verbal painting” through which she reinvents traditional visual modes as a personal modernist idiom. Close textual analysis of Bowen’s fictions forms the dominant methodology of this thesis and facilitates my delineation of her engagement with the Futurist and Surrealist aesthetics in addition to broader aspects of her visuality, including her treatment of the “vividly visual” dream-state to the distinct ocularcentricity of her writing. Ultimately, this thesis seeks to advance our knowledge of Bowen’s visual method and to offer a new approach in which to nuance our understanding of her modernism

Less strain, more gain_nano_patterning III-N thin films

Controlling the growth mechanism for nano-structures is one of the most critical topics in material science. In the past 10 years there has been intensive research worldwide in IIIN based nanowires for its many unique photonic and electrical properties at this scale. There are several advantages to nanostructuring III-N materials, including increased light extraction, increased device efficiency, reduction of efficiency droop, and reduction in crystallographic defect density. High defect densities that normally plague III-N materials and reduce the device efficiency are not an issue for nano-structured devices such as LEDs, due to the effective strain relaxation. Additionally regions of the light spectrum such as green and yellow, once found difficult to achieve in bulk planar LEDs, can be produced by manipulating the confinement and crystal facet growth directions of the active regions. A cheap and easily repeatable self-assembly nano-patterning technique at wafer scale was designed during this thesis for top down production of III-N nanowires. Through annealing under ammonia and N2 gas flow, the first reported dislocation defect bending was observed in III-N nanorods by in-situ transmission electron microscopy heating. By growing on these etched top down nanorods as a template, ultra-dense nanowires with apex tipped semi-polar tops were produced. The uniform spacing of 5nm between each wire is the highest reported space-filling factor at 98%. Finally by using these ultra-dense nanorods bridging the green gap of the light spectrum was possible, producing the first reported red, yellow, green light emission from a single nano-tip.

Bioengineering strategies to improve functional qualities of nisin

The abuse of antibiotics and the emergence of multi-drug resistant bacterial strains have created the need to explore alternative methods of controlling microbial pathogens. The bacteriocin family of antimicrobial peptides has been proposed as one such alternative to classic antibiotics. Nisin A belongs to the subgroup of bacteriocins called the lantibiotics, which contain several unusual amino acids as a consequence of enzyme-mediated post-translational modifications. As nisin is produced by generally regarded as safe (GRAS) microorganisms, it could potentially be applied in a clinical setting. However, as lantibiotics are naturally produced in such small quantities, this can hinder their industrial potential. In order to overcome this, several approaches can be utilised. For example, given the gene encoded nature of lantibiotics, genetic engineering approaches can be implemented in order to yield variants with enhanced properties. Here, the use of mutagenesis-based strategies was employed to obtain a derivative of nisin with enhanced bioactivity in vitro. Investigations with purified peptide highlighted the enhanced specific activity of this variant, nisin M21V, against food-borne Listeria monocytogenes strains. Furthermore, this specific enhanced bioactivity was evident in a mouse model of listeriosis. Reductions in bioluminescence and microbial counts in organs from infected mice were observed following treatment with nisin M21V compared to that of wild-type nisin A. Peptide bioengineering approaches were also implemented to obtain additional novel derivatives of nisin. The generation of “S5X” and “S33X” banks (representing a change of natural serines at positions 5 and 33 to all possible alternative residues) by a combination of site-saturation and site-directed mutagenesis led to the identification of several derivatives exhibiting improved stability. This allowed the rational design of variants with enhanced stability compared to that of wild type nisin. Another means of tackling issues associated with lantibiotic yield is to combine lantibiotics with other antimicrobials. This could circumvent the need for enhanced production while also reducing concentrations of the peptide antimicrobials. We observed that combinations of nisin variants and low levels of plant essential oils (thymol, carvacrol, trans-cinnamaldehyde) significantly controlled Gram negative foodborne pathogens in in vitro assays compared to nisin A-essential oil combinations. This enhanced control was also evident in model food systems. Nisin variants used in conjunction with carvacrol significantly reduced numbers of E. coli O157:H7 in apple juice while a commercial nisin preparation used in combination with citric acid significantly controlled C. sakazakii in infant milk formula. It is noteworthy that while nisin is generally associated with Gram positive targets, upon combination with plant essential oils the spectrum of inhibition was broadened to Gram negative targets.

Weathering the crisis? Managing democracy at a national broadcaster

With post-2008 political and economic crises as its backdrop, this inquiry into the political roles and functions of public service broadcasting (PSB) in Ireland is principally concerned with examining the capacities for and actuality of critical and counter-hegemonic professional journalistic and institutional mediations of crisis. Recognising the diversity of influences on the normative identity of Irish PSB, the dissertation adopts a sociological approach that acknowledges the systemic embedding of media institutions in the broader field of power. An initial tracing of the formative impacts of endogenous and exogenous forces on the democratic horizons of PSB suggests that the present crisis conjuncture does not represent promising terrain for engendering critical crisis and recovery imaginaries. A methodologically diverse intra-institutional empirical research agenda aims to explore at close hand Irish PSB’s contingent navigation of crisis, encompassing ethnographic observation in the newsroom, practitioner interviews and textual analysis of broadcast output. These methods afford close analysis of practices of journalistic production and reflexivity, self-conceptions of the journalistic habitus, and ideological affinities of crisis framings in broadcast output. These analyses are supplemented by a participant observation study of the possibilities for public agenda-building in a key institutional venue of public participation in broadcasting governance. The findings offer an evidential basis for the arguments that the crisis has prompted only minimal changes to professional norms and practices of representation and inclusion; that journalistic crisis framings tend toward effecting hegemonic repair by lending support to neoliberal crisis and recovery imaginaries; and that the institutional openings for the building of public counterpower are highly constrained. The overall conclusion is made that the normative democratic orientation embedded in the professional and institutional projects of public service broadcasting help render it ill-equipped to act as a re-democratising countervailing power against the democratic regressions engendered by the present crisis of democratic capitalism.

An archaeology of female monasticism in medieval Ireland

This thesis considers the archaeological evidence for female monasticism in medieval Ireland, with a particular emphasis on the later medieval period. Female monasticism has been considered from an archaeological perspective in several countries, most notably Britain, but has yet to be considered in any detail in Ireland. The study aims to bring together all the currently available evidence on female monasticism and consider it through an engendered archaeological approach. The data gathering for this research has been deliberately wide, and where gaps have been identified in the Irish evidence, comparative material from elsewhere has been considered. Nunneries should not be expected to conform to what has become the male monastic template of a claustrally-planned monastery. The research conducted shows a distinct and varied archaeology and architecture for medieval nunneries in Ireland which suggests that a claustral plan was not considered an essential part of a nunnery scheme. Nunneries provided an enclosed environment where women, for a variety of motives could become brides of Christ. Through the performance and celebration of the daily Divine Office, the Mass and seasonal liturgy, spaces used by the nunnery community were negotiated and transformed into a sacred Paradise on earth. However, rather than being isolated in the landscape nunneries in later medieval Ireland were located either within or close to walled towns, larger unenclosed settlements and settlement clusters and would have been well known throughout their hinterlands. This research concludes that nunneries were an intrinsic part of the medieval monastic landscape in Ireland and an essential component of patrons’ portfolios of patronage, at a particularly local level, and where they interacted closely with their local community.

Iterative reconstruction as a novel method of radiation dose reduction at computed tomography in patients with Crohn's disease

Prior work of our research group, that quantified the alarming levels of radiation dose to patients with Crohn’s disease from medical imaging and the notable shift towards CT imaging making these patients an at risk group, provided context for this work. CT delivers some of the highest doses of ionising radiation in diagnostic radiology. Once a medical imaging examination is deemed justified, there is an onus on the imaging team to endeavour to produce diagnostic quality CT images at the lowest possible radiation dose to that patient. The fundamental limitation with conventional CT raw data reconstruction was the inherent coupling of administered radiation dose with observed image noise – the lower the radiation dose, the noisier the image. The renaissance, rediscovery and refinement of iterative reconstruction removes this limitation allowing either an improvement in image quality without increasing radiation dose or maintenance of image quality at a lower radiation dose compared with traditional image reconstruction. This thesis is fundamentally an exercise in optimisation in clinical CT practice with the objectives of assessment of iterative reconstruction as a method for improvement of image quality in CT, exploration of the associated potential for radiation dose reduction, and development of a new split dose CT protocol with the aim of achieving and validating diagnostic quality submillisiever t CT imaging in patients with Crohn’s disease. In this study, we investigated the interplay of user-selected parameters on radiation dose and image quality in phantoms and cadavers, comparing traditional filtered back projection (FBP) with iterative reconstruction algorithms. This resulted in the development of an optimised, refined and appropriate split dose protocol for CT of the abdomen and pelvis in clinical patients with Crohn’s disease allowing contemporaneous acquisition of both modified and conventional dose CT studies. This novel algorithm was then applied to 50 patients with a suspected acute complication of known Crohn’s disease and the raw data reconstructed with FBP, adaptive statistical iterative reconstruction (ASiR) and model based iterative reconstruction (MBIR). Conventional dose CT images with FBP reconstruction were used as the reference standard with which the modified dose CT images were compared in terms of radiation dose, diagnostic findings and image quality indices. As there are multiple possible user-selected strengths of ASiR available, these were compared in terms of image quality to determine the optimal strength for this modified dose CT protocol. Modified dose CT images with MBIR were also compared with contemporaneous abdominal radiograph, where performed, in terms of diagnostic yield and radiation dose. Finally, attenuation measurements in organs, tissues, etc. with each reconstruction algorithm were compared to assess for preservation of tissue characterisation capabilities. In the phantom and cadaveric models, both forms of iterative reconstruction examined (ASiR and MBIR) were superior to FBP across a wide variety of imaging protocols, with MBIR superior to ASiR in all areas other than reconstruction speed. We established that ASiR appears to work to a target percentage noise reduction whilst MBIR works to a target residual level of absolute noise in the image. Modified dose CT images reconstructed with both ASiR and MBIR were non-inferior to conventional dose CT with FBP in terms of diagnostic findings, despite reduced subjective and objective indices of image quality. Mean dose reductions of 72.9-73.5% were achieved with the modified dose protocol with a mean effective dose of 1.26mSv. MBIR was again demonstrated superior to ASiR in terms of image quality. The overall optimal ASiR strength for the modified dose protocol used in this work is ASiR 80%, as this provides the most favourable balance of peak subjective image quality indices with less objective image noise than the corresponding conventional dose CT images reconstructed with FBP. Despite guidelines to the contrary, abdominal radiographs are still often used in the initial imaging of patients with a suspected complication of Crohn’s disease. We confirmed the superiority of modified dose CT with MBIR over abdominal radiographs at comparable doses in detection of Crohn’s disease and non-Crohn’s disease related findings. Finally, we demonstrated (in phantoms, cadavers and in vivo) that attenuation values do not change significantly across reconstruction algorithms meaning preserved tissue characterisation capabilities with iterative reconstruction. Both adaptive statistical and model based iterative reconstruction algorithms represent feasible methods of facilitating acquisition diagnostic quality CT images of the abdomen and pelvis in patients with Crohn’s disease at markedly reduced radiation doses. Our modified dose CT protocol allows dose savings of up to 73.5% compared with conventional dose CT, meaning submillisievert imaging is possible in many of these patients.

Synthesis and evaluation of novel functionalised indoles as anticancer agents

This thesis outlines the design and application of new routes towards a range of novel bisindolylmaleimide and indolo[2,3-a]carbazole derivatives, and evaluation of their biological effects and their chemotherapeutic potential. A key part of this work focussed on utilising a hydroxymaleimide as a replacement for the prevalent lactam/maleimide functionality and forming a series of novel derivatives through substitution on the indole nitrogens. To achieve this, a robust synthetic strategy was developed which allowed access to key maleic anhydride intermediates using Perkin-type methodology. These hydroxymaleimides were further modified via a Lossen rearrangement to furnish a series of analogues containing a 6-membered F-ring. The theme of F-ring modulation was further expanded through the utilisation of a second route involving the design and synthesis of β-keto ester intermediates, which afforded novel derivatives containing pyrazolone and isocytosine headgroups, and various N-substituents. Work on a further route involving a dione intermediate resulted in the isolation of a bisindolyl derivative with a novel imidazole F-ring. Following the synthesis of 42 novel compounds, extensive screening was undertaken using the NCI-60 cell line screen, with twelve candidates progressing to evaluation via the five dose assay. This led to the identification of several lead compounds with high cytotoxicity and excellent selectivity profiles, which included derivatives with low nanomolar GI50 values against specific cancer cell lines, and also derivatives with selective cytotoxicity. Preliminary results from a kinase screen indicated noteworthy selectivity towards GSK3α/β and PIM1 kinases, with low micromolar IC50 values being observed for these enzymes.

Building an index of well-being for children living in Ireland: conceptual, measurement and policy considerations

This study conceptualised and measured children’s well-being in Ireland and considered how such conceptualisations and approaches to the measurement of well-being might inform social policy for children and families living in Ireland. This research explored what is meant by children’s well-being and how it can be conceptualised and measured so as to reflect the multi-dimensionality of the concept. The study developed an index of well-being that was both theoretically and methodologically robust and could be meaningfully used to inform social policy developments for children and their families. For the first time, an index of well-being for children was developed using an explicitly articulated unifying theory of children’s well-being. Moreover, for the first time an index of wellbeing was developed for 13-year old children living in Ireland using data from Wave 2 of the national longitudinal study of children. The Structural Model of Child Well-being (SMCW), the theoretical framework that underpins the development of this study’s index, offers a comprehensive understanding of well-being. The SMCW builds on, and integrates, a range of already-established theories concerning children’s development, their agency, rights and capabilities into a unifying theory that explains well-being in its entirety. This conceptualisation of well-being moves beyond the narrow focus on child development adopted in some recent studies of children’s well-being and which perpetuate individualised and self-responsibilising conceptualisations of well-being. This study found that the SMCW can be meaningfully applied, both theoretically and operationally, to the construction of an index of well-being for children. While it was not the purpose of this study to validate the SMCW, in the process of developing the index, I concluded that there was a theoretical ‘fit’ between the conceptual orientation of the SMCW and the wider children’s well-being literature. The ‘nested’ structure of the SMCW facilitated the identification of domains, sub-domains and indicators of well-being reflecting typical conventions of index construction. The findings from the resulting index, in both its categorical and continuous forms, demonstrated how a comprehensive theory of well-being can be used to illustrate how children are faring and which children are experiencing poorer or better well-being. Furthermore, this study demonstrated how the SMCW and the resultant index can be meaningfully used to support the implementation and review of the national policy framework for children and young people in Ireland.

Ó Sheán Clárach Mac Domhnaill go dtí Nioclás Tóibín: traidisiún na hamhránaíochta ins na Déise

Féachann an tráchtas seo le solas a chaitheamh ar an amhránaíocht mar a chleachtaítí agus mar a chleactaítear fós i gcontae Phort Láirge í. Ardaítear ann ceisteanna a bhaineann le seachadadh agus le sealbhú na n-amhrán I measc an phobail i gceantar na nDéise sa tréimhse c.1750-1960, ó aimsir Sheáin Chláraigh go dtí an ré sin ina raibh Nioclás Tóibín, ‘rí-amhránaí Éireann’, ar bhuaic a réime. Cuirtear spéis anseo i bhfás agus i dteacht chun cinn an Rómánsachais agus (a leathchúpla) an náisiúnachais ar Mhór-roinn na hEorpa in earr an 18ú haois agus amach san 19ú haois; ar thionchar na ngluaiseachtaí sin i bhfad ó bhaile ar Éirinn i gcoitinne san aimsir úd; orthu sin a raibh díolamaí amhrán á gcur in eagar acu in Éirinn san 19ú agus amach san 20ú haois; agus, ar deireadh, ar an stór amhrán mar atá le clos inniu I measc na ndaoine i nGaeltacht na Déise.

Drug prescribing patterns in the General Medical Services Scheme in Ireland and projected costs to 2026

The primary objective is to investigate the main factors contributing to GMS expenditure on pharmaceutical prescribing and projecting this expenditure to 2026. This study is located in the area of pharmacoeconomic cost containment and projections literature. The thesis has five main aims: 1. To determine the main factors contributing to GMS expenditure on pharmaceutical prescribing. 2. To develop a model to project GMS prescribing expenditure in five year intervals to 2026, using 2006 Central Statistics Office (CSO) Census data and 2007 Health Service Executive{Primary Care Reimbursement Service (HSE{PCRS) sample data. 3. To develop a model to project GMS prescribing expenditure in five year intervals to 2026, using 2012 HSE{PCRS population data, incorporating cost containment measures, and 2011 CSO Census data. 4. To investigate the impact of demographic factors and the pharmacology of drugs (Anatomical Therapeutic Chemical (ATC)) on GMS expenditure. 5. To explore the consequences of GMS policy changes on prescribing expenditure and behaviour between 2008 and 2014. The thesis is centered around three published articles and is located between the end of a booming Irish economy in 2007, a recession from 2008{2013, to the beginning of a recovery in 2014. The literature identified a number of factors influencing pharmaceutical expenditure, including population growth, population aging, changes in drug utilisation and drug therapies, age, gender and location. The literature identified the methods previously used in predictive modelling and consequently, the Monte Carlo Simulation (MCS) model was used to simulate projected expenditures to 2026. Also, the literature guided the use of Ordinary Least Squares (OLS) regression in determining demographic and pharmacology factors influencing prescribing expenditure. The study commences against a backdrop of growing GMS prescribing costs, which has risen from e250 million in 1998 to over e1 billion by 2007. Using a sample 2007 HSE{PCRS prescribing data (n=192,000) and CSO population data from 2008, (Conway et al., 2014) estimated GMS prescribing expenditure could rise to e2 billion by2026. The cogency of these findings was impacted by the global economic crisis of 2008, which resulted in a sharp contraction in the Irish economy, mounting fiscal deficits resulting in Ireland's entry to a bailout programme. The sustainability of funding community drug schemes, such as the GMS, came under the spotlight of the EU, IMF, ECB (Trioka), who set stringent targets for reducing drug costs, as conditions of the bailout programme. Cost containment measures included: the introduction of income eligibility limits for GP visit cards and medical cards for those aged 70 and over, introduction of co{payments for prescription items, reductions in wholesale mark{up and pharmacy dispensing fees. Projections for GMS expenditure were reevaluated using 2012 HSE{PCRS prescribing population data and CSO population data based on Census 2011. Taking into account both cost containment measures and revised population predictions, GMS expenditure is estimated to increase by 64%, from e1.1 billion in 2016 to e1.8 billion by 2026, (ConwayLenihan and Woods, 2015). In the final paper, a cross{sectional study was carried out on HSE{PCRS population prescribing database (n=1.63 million claimants) to investigate the impact of demographic factors, and the pharmacology of the drugs, on GMS prescribing expenditure. Those aged over 75 (ẞ = 1:195) and cardiovascular prescribing (ẞ = 1:193) were the greatest contributors to annual GMS prescribing costs. Respiratory drugs (Montelukast) recorded the highest proportion and expenditure for GMS claimants under the age of 15. Drugs prescribed for the nervous system (Escitalopram, Olanzapine and Pregabalin) were highest for those between 16 and 64 years with cardiovascular drugs (Statins) were highest for those aged over 65. Females are more expensive than males and are prescribed more items across the four ATC groups, except among children under 11, (ConwayLenihan et al., 2016). This research indicates that growth in the proportion of the elderly claimants and associated levels of cardiovascular prescribing, particularly for statins, will present difficulties for Ireland in terms of cost containment. Whilst policies aimed at cost containment (co{payment charges, generic substitution, reference pricing, adjustments to GMS eligibility) can be used to curtail expenditure, health promotional programs and educational interventions should be given equal emphasis. Also policies intended to affect physicians prescribing behaviour include guidelines, information (about price and less expensive alternatives) and feedback, and the use of budgetary restrictions could yield savings.

Obstetric mode of delivery and child psychological development

Background/aims: Objective of the current thesis is to investigate the potential impact of birth by Caesarean section (CS) on child psychological development, including autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), behavioural difficulties and school performance. Structure/methods: Published literature to date on birth by CS, ASD and ADHD was reviewed (Chapter 2). Data from the UK Millennium Cohort Study (MCS) were analysed to determine the association between CS and ASD, ADHD and parent-reported behavioural difficulties (Chapter 3). The Swedish National Registers were used to further assess the association with ASD, ADHD and school performance (Chapters 4-6). Results: In the review, children born by CS were 23% more likely to be diagnosed with ASD after controlling for potential confounders. Only two studies reported adjusted estimates on the association between birth by CS and ADHD, results were conflicting and limited. CS was not associated with ASD, ADHD or behavioural difficulties in the UK MCS. In the Swedish National Registers, children born by CS were more likely to be diagnosed with ASD or ADHD. The association with elective CS did not persist when compared amongst siblings. There was little evidence of an association between birth by elective CS and poor school performance. Children born by elective CS had slight reduction in school performance. Conclusions: The lack of association with the elective CS in the sibling design studies indicates that the association in the population is most probably due to confounding. A small but significant association was found between birth by CS and school performance. However, the effect may have been due to residual confounding or confounding by indication and should be interpreted with caution. The overall conclusion is that birth by CS does not appear to have a causal relationship with the aspects of child psychological development investigated.

Development of miniaturized antennas and adaptive tuning solutions for body sensor network applications

Wireless Sensor Networks (WSNs) are currently having a revolutionary impact in rapidly emerging wearable applications such as health and fitness monitoring amongst many others. These types of Body Sensor Network (BSN) applications require highly integrated wireless sensor devices for use in a wearable configuration, to monitor various physiological parameters of the user. These new requirements are currently posing significant design challenges from an antenna perspective. This work addresses several design challenges relating to antenna design for these types of applications. In this thesis, a review of current antenna solutions for WSN applications is first presented, investigating both commercial and academic solutions. Key design challenges are then identified relating to antenna size and performance. A detailed investigation of the effects of the human body on antenna impedance characteristics is then presented. A first-generation antenna tuning system is then developed. This system enables the antenna impedance to be tuned adaptively in the presence of the human body. Three new antenna designs are also presented. A compact, low-cost 433 MHz antenna design is first reported and the effects of the human body on the impedance of the antenna are investigated. A tunable version of this antenna is then developed, using a higher performance, second-generation tuner that is integrated within the antenna element itself, enabling autonomous tuning in the presence of the human body. Finally, a compact sized, dual-band antenna is reported that covers both the 433 MHz and 2.45 GHz bands to provide improved quality of service (QoS) in WSN applications. To date, state-of-the-art WSN devices are relatively simple in design with limited antenna options available, especially for the lower UHF bands. In addition, current devices have no capability to deal with changing antenna environments such as in wearable BSN applications. This thesis presents several contributions that advance the state-of-the-art in this area, relating to the design of miniaturized WSN antennas and the development of antenna tuning solutions for BSN applications.

Open-source virtual bronchoscopy for image guided navigation

This thesis describes the development of an open-source system for virtual bronchoscopy used in combination with electromagnetic instrument tracking. The end application is virtual navigation of the lung for biopsy of early stage cancer nodules. The open-source platform 3D Slicer was used for creating freely available algorithms for virtual bronchscopy. Firstly, the development of an open-source semi-automatic algorithm for prediction of solitary pulmonary nodule malignancy is presented. This approach may help the physician decide whether to proceed with biopsy of the nodule. The user-selected nodule is segmented in order to extract radiological characteristics (i.e., size, location, edge smoothness, calcification presence, cavity wall thickness) which are combined with patient information to calculate likelihood of malignancy. The overall accuracy of the algorithm is shown to be high compared to independent experts' assessment of malignancy. The algorithm is also compared with two different predictors, and our approach is shown to provide the best overall prediction accuracy. The development of an airway segmentation algorithm which extracts the airway tree from surrounding structures on chest Computed Tomography (CT) images is then described. This represents the first fundamental step toward the creation of a virtual bronchoscopy system. Clinical and ex-vivo images are used to evaluate performance of the algorithm. Different CT scan parameters are investigated and parameters for successful airway segmentation are optimized. Slice thickness is the most affecting parameter, while variation of reconstruction kernel and radiation dose is shown to be less critical. Airway segmentation is used to create a 3D rendered model of the airway tree for virtual navigation. Finally, the first open-source virtual bronchoscopy system was combined with electromagnetic tracking of the bronchoscope for the development of a GPS-like system for navigating within the lungs. Tools for pre-procedural planning and for helping with navigation are provided. Registration between the lungs of the patient and the virtually reconstructed airway tree is achieved using a landmark-based approach. In an attempt to reduce difficulties with registration errors, we also implemented a landmark-free registration method based on a balanced airway survey. In-vitro and in-vivo testing showed good accuracy for this registration approach. The centreline of the 3D airway model is extracted and used to compensate for possible registration errors. Tools are provided to select a target for biopsy on the patient CT image, and pathways from the trachea towards the selected targets are automatically created. The pathways guide the physician during navigation, while distance to target information is updated in real-time and presented to the user. During navigation, video from the bronchoscope is streamed and presented to the physician next to the 3D rendered image. The electromagnetic tracking is implemented with 5 DOF sensing that does not provide roll rotation information. An intensity-based image registration approach is implemented to rotate the virtual image according to the bronchoscope's rotations. The virtual bronchoscopy system is shown to be easy to use and accurate in replicating the clinical setting, as demonstrated in the pre-clinical environment of a breathing lung method. Animal studies were performed to evaluate the overall system performance.