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Developing and Assessing the Effectiveness of a Web-based Breastfeeding Educational Resource on Exclusive Breastfeeding Rate among Saudi Women
No full textBackground: Breastfeeding is not only a very cost-effective way of feeding a baby, but it is also associated with multiple health benefits for both mothers and infants. Henceforth, the World Health Organization highly recommends early initiation of breastfeeding within an hour after birth, followed by exclusive breastfeeding for up to six months. However, the rates of early initiation of breastfeeding and exclusive breastfeeding vary around the world, and in some countries, they are well below the WHO targets. Similarly, in Saudi Arabia, the rate of early initiation of breastfeeding ranges from 26.3% in the Northern region to 62.7% in the Southern region. Furthermore, the rate of exclusive breastfeeding at six months after birth varies from 19.2% to 28%. Despite national efforts to promote breastfeeding, a decline in breastfeeding practices has been recorded, coinciding with increased use of infant formula. Introducing formula milk during hospital stays in Saudi Arabia is common practice. Several misconceptions about body shape, the safety of colostrum, and breastmilk insufficiency, coupled with rapid economic growth, have contributed to this decline and early breastfeeding cessation, even though Saudi women are offered breastfeeding education during pregnancy. Therefore, there was a need to develop an online educational intervention to motivate Saudi women to breastfeed for a longer duration. Saudi Arabia has a deep-rooted cultural heritage based on the Islamic religion, and its main language is Arabic. Hence, the cultural and linguistic aspects of the educational intervention were considered important determinants of its successful implementation.Aim: The aim of this program of Higher Degree Research (HDR) was to develop and assess the effectiveness of a Web-based Breastfeeding Educational Resource (WEBBER) on exclusive breastfeeding rate during the hospital stay until one month after birth.Method: The multi-method study was carried out in three phases to address the research aim. In the first phase, a systematic review was conducted to collect evidence-based information. The content of the website was based on the knowledge gaps identified in the systematic review, the WHO recommendation and the Milky Way app. In the second phase, the content of the website was finalised through a consensus development conference involving local stakeholders from the participating hospital in Saudi Arabia and university researchers. Participants of the Consensus Development Conference were asked to give feedback before the meeting, and changes were made to the content accordingly. The meeting was conducted on Zoom, and polling was used to indicate whether consensus was reached about the content, images and layout. The Persuasive System Design model informed the framework of the website development phase. The third phase was divided into two stages. In the first stage, a quasi-experimental study with a before and after intervention design was used to assess the effectiveness of the Web-based breastfeeding educational resource in promoting breastfeeding practices. An online survey was conducted to collect information about the breastfeeding practices during a hospital stay and at one month after birth before (Standard Care group) and after (Intervention group) giving access to the website. In the second stage, a semi-structured interview was undertaken to explore women’s experiences using the website. The interview was digitally recorded and transcribed verbatim using the Otter application before translating into English. The quantitative data was analysed using R language for statistical computing. A log-binomial regression model was used to adjust for any confounding factors that were identified. The qualitative data was analysed using content and thematic analysis.Results: A total of sixteen studies were included in the systematic review. Data from ten studies that reported on breastfeeding knowledge demonstrated that 42.3% to 82.3% of Saudi women had good knowledge. However, several gaps in knowledge were identified including managing breastfeeding challenges. A meta-analysis of seven studies that reported on attitudes showed that most Saudi women hold positive attitudes towards breastfeeding. However, around 40% of women believed that formula milk was as healthy as breastmilk, and 59.4% believed that formula feeding was more convenient. The literature review was crucial in developing the content of the website. After making changes to the content based on feedback received from the members of the Consensus Development Conference, 100% agreement about the content, layout and images was achieved during the meeting. This confirmed the cultural and linguistic appropriateness of the content of the website, which was successfully developed using the Persuasive Systems Design model. Findings from the quasi-experimental experimental demonstrated an almost three times increase in the rate of exclusive breastfeeding at one month after birth in the intervention group that was given access to the website.Several predictors of exclusive breastfeeding were identified, including intention to breastfeed for six months or more, baby not receiving pre-made infant formula, and unemployment status of the women. Thematic analysis of the data from the semi-structured interview revealed three themes, including “Satisfying,” “Helpful,” and “Motivational.” Participants found the website “satisfying” due to its “Accessibility,” “Visual attraction,” “User-friendliness,” “Informative content,” “Trustworthiness,” and “Uniqueness.” They qualified the website as being helpful because it was perceived as a “Problem solver,” “Supportive,” and “Confidence booster.” The four sub-themes associated with “Motivational” were “Motivation to continue breastfeeding,” “Preparedness for managing breastfeeding challenges,” “Facilitating the continuation of breastfeeding,” and “Enhancement of intention to Breastfeed for a longer period.” Overall, the women’s experience of using the website was very positive.Conclusion: This program of Higher Degree Research (HDR) has demonstrated the effectiveness of the Web-based Breastfeeding Education Resource in improving the exclusive breastfeeding rate during the hospital stay until one month after birth in Saudi Arabia. The Consensus Development Conference facilitated the engagement with local stakeholders, who ensured the cultural and linguistic appropriateness of the evidence-based content derived from the systematic review, WHO and Milky Way App. The Persuasive Systems Design model was successfully employed in developing the website, which was confirmed by the positive feedback from breastfeeding women who felt more motivated to breastfeed. This study has demonstrated that a women-centred online breastfeeding educational intervention can improve breastfeeding practices in Saudi Arabia.</p
Structural design and multifunctional applications of shear-stiffening composites
No full textRecent advancements in the dynamic behavior and structural design of shear-stiffening materials have garnered considerable attention due to their adaptive mechanical properties under varying strain rates. This thesis explores the structural innovations and multifunctional properties of shear-stiffening composites, spotlighting their versatile applications across diverse sectors such as transportation, healthcare, and protective gear. It highlights the innovative gradient designs inspired by natural phenomena, advanced magnetorheological systems, pioneering energy-harvesting technologies and beneficial interactions with the structural integrity of the fibers.Drawing inspiration from the naturally occurring gradient structure of the squid beak, novel gradient shear-stiffening elastomer have been crafted using direct ink writing techniques. These materials exhibit superior toughness, flexibility, and impact resistance, rendering them ideal for applications that demand efficient energy dissipation under complex loading scenarios. The biomimetic approach to their fabrication marks a significant leap in mechanical performance, particularly enhancing impact protection and the functionality of wearable technologies.In the realm of transportation, especially in rail vehicle design, shear-stiffening elastomers have been successfully implemented in the form of magnetorheological shear-stiffening elastomer joints. These innovative joints address the challenge of balancing conflicting stiffness demands in train bogies, offering tunable stiffness via external magnetic fields and leveraging inherent frequency-dependent properties. MRSSE joints enhance operational stability on straight tracks while providing necessary flexibility on curves, demonstrating exceptional performance under dynamic conditions through comprehensive MTS testing and dynamic modeling.Moreover, the fusion of shear-stiffening materials with liquid metal in the domain of triboelectric nanogenerators technology has fostered the creation of multifunctional self-powered devices. These liquid metal-based shear stiffening elastomers integrate electrothermal aluminum foil and shear-stiffening elastomers, crafting devices capable of simultaneous energy harvesting, Joule heating, and enhanced mechanical impact protection. These devices are particularly promising for deployment in intelligent medical plasters, wearable electronics, and personal healthcare systems, offering innovative strategies for designing sensors that boast superior anti-impact properties.Furthermore, the thesis extends its exploration into Kevlar-reinforced shear stiffening elastomer, adopting advanced viscoelastic shear-stiffening elastomers as the matrix and integrating high-toughness Kevlar aramid fibers. This novel approach leverages the synergistic dynamic interactions between the rate-dependent strengthening behavior of the matrix and the structural integrity of the fibers, markedly enhancing impact resistance across diverse strain rates and loading scenarios. This advancement is particularly applicable in high-end equipment manufacturing, such as Formula racing, where these composites demonstrate substantial improvements in durability and shock absorption, bridging the gap in impact resistance often noted with conventional fiber-reinforced polymers.Overall, this thesis comprehensively explores the latest advancements in the structural design and dynamic behavior of shear-stiffening materials, and it emphasizes their widespread applications in sectors such as transportation, healthcare, and protective equipment. Additionally, it suggests that future research could offer more possibilities for enhancing the performance, diversifying the structures, and augmenting the functionalities of shear-stiffening composites.</p
Counting Connections: Exploring Preschool Numeracy, Early Interventions and Parent-Child Relationships
No full textEarly numeracy skills play an important role in children’s long-term academic success. Despite substantial evidence highlighting the critical role of home-based numeracy interactions in fostering early numeracy skills, significant gaps remain in our understanding of how family and household characteristics, as well as parent-child relationship dynamics, influence children's numeracy outcomes. This thesis, comprised of four studies, will comprehensively explore how parents currently approach numeracy learning and their perspectives on preschool numeracy interventions. It will also explore family financial and household factors beyond the standard measures of socioeconomic status that contribute to children’s numeracy outcomes. Additionally, this thesis will explore the effects of maternal well-being and the quality of the parent-child relationship on early intervention engagement and preschool numeracy outcomes.The aim of Study 1 was to explore how mothers support their children's developing numeracy skills and adjust their numeracy practices when prompted to recognise the numeracy potential of the activity. To achieve this, the numeracy conversations of 30 mother-child dyads were observed during a laboratory task involving height and weight measurements. The children were between 37 and 46 months old (M = 41 months, SD = 3.19), and all dyads lived in the Illawarra region, NSW, Australia. Maternal scaffolding (task completion time, verbosity, and conversation turns) was positively related to children’s numeracy scores. Mothers' use of numeracy and reciprocal conversation turns predicted children’s numeracy utterances. Dyads were found to prioritise simple numbering skills, and few numeracy-related interactions were observed during the measurement task in the absence of the numeracy prompt. A bidirectional relationship between maternal and child numeracy utterances was observed when dyads received the numeracy prompt. The overall findings of Study 1 emphasise the importance of parental involvement and the critical role of interactive and responsive parent-child interactions in fostering the development of preschool numeracy skills.Study 2 examined the effects of financial literacy and maternal encouragement of numeracy skills on the relationship between socioeconomic status (using area-level deprivation and maternal education as indicator variables) and children’s ascending and descending counting skills. Participants (N = 5839) were drawn from the longitudinal Growing up in New Zealand population cohort when children were 54 months of age. The results of the serial mediation model found that area-level deprivation and maternal education each had a direct effect on child numeracy outcomes and a simple indirect effect through financial literacy but not through maternal encouragement of numeracy. A serial mediation effect was found for the relationship between area-level deprivation and maternal education on child numeracy outcomes through a pathway of financial literacy and maternal encouragement of numeracy. Overall, the results of Study 2 highlight the necessity for interventions that extend beyond simply promoting home-based numeracy activities to encompass broader social, emotional, and economic support at a population level.Study 3 explored mothers’ (N = 68) knowledge and perspectives on numeracy, their family's activities at home, and their preferences for a home numeracy intervention. Participating mothers completed an online survey, had children aged 3 to 5 years (M = 3.67, SD = .64) and resided in the Illawarra. Mothers primarily provided simple definitions of numeracy, had difficulty identifying the numeracy potential of many everyday home learning activities, and tended to prioritise more straightforward concepts during numeracy learning experiences. Preferred family activities were reported to vary, and a considerable proportion of mothers indicated they avoid activities when they perceive they lack the required knowledge or expertise. Lack of available time, family stress, and children’s behaviour were the most common intervention engagement obstacles reported. Mothers also demonstrated a preference for unstructured, physical, flexible, and time-limited interventions with minimal additional support. Overall, the results of Study 3 demonstrate that labour-intensive or time-consuming home learning interventions may hold little appeal for busy families.The final study assessed the effectiveness of a community-informed preschool home numeracy intervention and explored the effects of maternal well-being and parent-child relationship qualities on intervention engagement and children’s numeracy outcomes. Using a randomised waitlist-controlled design, 24 mother-child dyads participated in a 4-week home numeracy intervention. The children were between 37 and 46 months old (M = 41 months, SD = 3.19), and all dyads lived in the Illawarra. The intervention comprised a printed resource manual developed for this research, which contained games, activities, and conversations for families (e.g., clapping games, pretend money play, estimating heights) to enhance counting, numerical relations, numeral knowledge, and arithmetic. Families in this pilot study were asked to spend at least five minutes daily on any of the activities, choosing as many or as few activities as desired across the 4-weeks. Both the experimental and waitlist control groups showed notable improvement in child numeracy scores post-intervention, with no significant difference between the groups. Maternal math anxiety negatively impacted children's numeracy scores and significantly predicted baseline performance. Maternal education, maternal anxiety, and maternal perceptions of parent-child relationship dependency collectively explained over half of the variance in improvements in child numeracy outcomes. Closeness in the parent-child relationship predicted intervention engagement. Overall, the findings of Study 4 suggest that interventions should focus on enhancing the quality of interactions and be responsive to families' emotional and relational contexts to improve preschool numeracy outcomes effectively.Taken together, the studies within this thesis generate new knowledge about the critical role of parental and household characteristics and the impact of parent-child relationship qualities on the numeracy experiences children have at home. It also highlights the need for researchers and educators to recognise the broader needs of the family system and consider how family dynamics can influence and be used to improve preschool numeracy interventions. Specifically, these findings demonstrate that addressing economic deprivation and embedding interventions with strategies that promote parental well-being and closeness within the parent-child relationship may help to provide effective and inclusive interventions to improve numeracy outcomes for all children.</p
The impact of human-dog interactions on psychophysiological indicators of human health & well-being
No full textHuman-animal interactions, particularly those involving companion animals like dogs, are widely believed to promote health and well-being. The inclusion of dogs into human health and well-being interventions is currently a burgeoning field. While the symbiotic nature of human-dog relationships, the development of attachment bonds, and perceived benefits to human health have attracted much scientific interest, the mechanisms through which human-dog interactions may confer health benefits to humans are still poorly understood. Progress in this field has been limited by significant variability in research methodologies, a reliance on subjective psychological measures, the complexity of human-animal dynamics and individual differences, and limited research in naturalistic settings. Developing rigorous research methodology is essential for understanding the psychophysiological processes involved and informing evidence-based interventions that utilize human-animal interactions to improve human health and well-being. The aim of the program of research reported in this thesis is to establish evidence for psychological and physiological mechanisms that may underlie health benefits conferred by human-dog interactions. It starts with a thorough review of existing knowledge in the field, followed by studies to develop and test novel methods to address limitations in previous research. The latter included the use of portable psychophysiological devices to measure heart and brain activity in real world situations involving interactions with dogs in comparison to baseline and standard relaxation conditions.</p
Injury in Youth Elite Footballers: From Surveillance to Prevention
No full textIntroduction: Elite youth players experience increasingly rigorous training and match demands from youth to senior football whilst being exposed to psychological (e.g., academic demands) and physiological stressors (e.g., physical maturation), potentially affecting injury risk negatively. To prevent injuries, frameworks suggest a stepwise approach from injury surveillance to testing an intervention in a controlled setting, before evaluating its effectiveness within ‘real-world’ context. Despite a growing number of injury surveillance studies in youth (elite) footballers, no research with third party data collection methods has yet investigated the impact of time-loss injury on different football participation levels, i.e. no participation as ‘full’ time-loss and reduced / modified participation as ‘partial’ time-loss), and none is available from Australia. Additionally, considering Australian youth elite players are engaged in part-time football academies plus full-time schooling, it is unclear whether certain yearlong patterns such as season phases, school holidays or periods of returning to school affect incidence rates or burden.Multimodal injury prevention systems in youth football commonly contain exercise-based injury prevention programs, such as the 11+, which is known to reduce injuries and improve physical performance. The duration to complete the full 11+ program at training presents a notable barrier to implementation, with re-scheduling parts of the 11+ outside of training as a possible solution. Football Australia’s “Perform+” adapted the 11+ to provide flexible scheduling of strength, balance and power exercises (11+ Part 2), with the running exercises (11+ Parts 1 and 3) maintained as warm-up, but adherence and compliance to the Perform+ in youth elite footballers has not been investigated to date.Hence, the aims of this thesis were to describe injuries in Australian elite youth footballers with focus on recording methods to distinguish between full and partial time-loss injury burden in Chapter 2; investigating patterns of injury incidence rates and burden within combined Pre-, Start-of-, Mid-, and End-of-Season and school-holiday phases in Chapter 3; in Chapter 4, to assess injury and performance outcomes when Part 2 of the 11+ is either performed at training or at home 3 × / week; and finally, to describe adherence to individual exercises within Football Australia’s Perform+ (performance and running parts), the preference or timing of exercises and the remaining barriers in Chapter 5.Methods: Medical attention injury (including time-loss and non-time-loss), individual football exposure, body mass and growth data were collected from 118 male elite footballers (U13–U18) over three consecutive seasons (two full seasons from 2017 – 2019, season 2019/2020 was interrupted by 16 weeks of COVID-19 lockdown or training restrictions) according to the Football Consensus Statement. This injury surveillance forms part of Chapters 2 to 4. In Chapter 2, the number of total, full and partial days lost per 1000 hours of exposure were used to calculate the respective injury burden with the proportion of partial time-loss described for different injury characteristics such as injury severity. In Chapter 3, pooled injury incidence rate and burden per season or school / holiday phases from 2017 – 2020 (until the COVID-19 lockdown) were calculated for all injuries. To compare between season or school / holiday phases, injury rate ratios (IRR) for injury incidences were assessed using Generalised Linear Mixed Models whilst including growth rates as a covariate and offsetting for football exposure. 99% confidence intervals were used to determine differences in injury burden between phases. In Chapter 4, the rescheduled 11+ program efficacy was established by assessing differences between home (HG) and training groups (TG) regarding time to stabilisation, eccentric hamstring strength and countermovement jump height four times during the 2019 football season, in addition to the established injury surveillance. 65 male elite footballers (U13 – U16) were stratified according to age, known previous injury history and baseline hamstring strength before matched pairs were randomly assigned to the home or training groups. Linear mixed-models were used to evaluate main and interaction effects of group and time with either rate of growth or rate of body mass included as covariate. Bonferroni post-hoc tests were used to account for multiple comparisons. Differences in time-loss and non-time-loss injuries were determined using a 2-tailed Z test for a comparison of rates. Weekly adherence of the home group was established via an online survey. Finally, in Chapter 5, a cross-sectional online survey was disseminated to top-tier female and male U13-U18 Australian and New Zealand footballers between 2021 and 2022. Statistical comparisons were made between the adherence to Perform+ parts (performance / running) and playing groups (goalkeeper / field players and females / males). Barriers were identified via thematic analysis.Results: In Chapter 2, 243 time-loss injuries with an average of 21 days lost (median 9 days) per injury were observed in 94 players. Injury burden (137.2 days lost/1000h, 95% CI 133.4 – 141.0) was comprised of 23% (31.9 days lost/1000h, 95% CI 30.1 – 33.8) partial time-loss and 77% (105.3 days lost/1000h, 95% CI 102.0 - 108.6) full time-loss burden. Injuries of moderate severity (8-28 days lost) showed 40% of partial time-loss. Time-loss injury incidence rate (6.6 injuries/1000h, 95% CI 5.8 – 7.5), the number of severe injuries (16%) and the distribution of time-loss and non-time-loss injuries (56% and 44%) were comparable to other reports in elite youth footballers. In Chapter 3, considering the reduced number of weeks from the 2019/2020 season, 202 time-loss and 169 non-time-loss injuries were observed in 94 players, with growth rate significantly affecting time-loss injury incidence rate. Medical attention and non-time-loss injury incidence rates were higher during Pre-season (IRR 1.65, 95% CI 1.12 – 2.18, p =0.01; IRR 2.08, 95% CI 1.02 – 3.14, p =0.02, respectively), and Mid-season showed a higher non-TL incidence rate (IRR 2.15, 95% CI 0.97 – 3.33, p =0.02) and burden (69 days with injury/1000hrs, 99% CI 47 – 103) compared to End-of-Season (25 days with injury/1000hrs, 99% CI 15 – 45). Medical attention injury rates and partial time-loss injury burden were higher during school compared to holiday periods (IRR 0.6, 95% CI 0.37 – 0.91, p =0.04; 61 partial days lost/1000hrs, 99% CI 35 – 104; 13 partial days lost/1000hrs, 99% CI 8 – 23). Chapter 4 demonstrated that relative to baseline, eccentric hamstring strength (HG 4.3 kg, 95% CI to 5.7, p Conclusion: Australian youth elite footballers experience similar injuries to youth footballers from other countries and have shown for the first time, that whilst being injured, almost one quarter of the time-loss injury burden was still spent being part of some team football activities. Furthermore, considering the complex nature of injury occurrence, season phase and return-to-school may be considered as external risk factors for elite academy footballers. Within injury prevention programs, a flexible delivery of exercises can be successful and is preferred by the majority of youth players. To continue to improve injury prevention program adherence, educating youth players directly on injury and injury prevention may provide a practical solution in elite male and female youth football. Key stakeholders in football can use the findings of this thesis to support the optimisation of multimodal injury prevention systems.</p
The impact of sublethal pesticide exposure on behaviour, physiology, and molecular markers in the Central Bearded Dragon (<i>Pogona vitticeps</i>): a trigger for inclusion in conservation, government, and risk assessment policy
No full textAssessment of non-target impacts of pesticides used widely in agriculture and pest management rarely consider reptiles. Despite their integral role in all ecosystems, particularly arid ecosystems, reptiles are not included in risk assessments. Two pesticides used in agricultural pest management are fipronil and fenitrothion. Across two field-based before-after-control-impact (BACI) design experiments in semi-arid and arid Australia the sublethal exposure of these pesticides was assessed in a widespread, arid-zone agamid species, the Central Bearded Dragon (Pogona vitticeps) using relevant sampling intervals. Firstly, to investigate the impact of these pesticides on basic physiological and behavioural parameters of P. vitticeps, fipronil and fenitrothion were applied in a single ecologically relevant dose via oral gavage at study site 1 (Nombinnie Nature Reserve) and applied via ultra-low volume (ULV) aerial spray at study site 2 (Fowlers Gap Arid Zone Research Station). Exposure scenarios were designed to replicate the use of these two pesticides in locust control in Australia. At study site 1,I assessed blood, movement activity, and body condition parameters (SBMI) before and after dosing (chapter 2). At study site 2 ,I assessed blood, movement activity, SBMI, ectoparasite count and measured environmental conditions (chapter 3). To build our knowledge further and incorporate a holistic approach, based at study site 1,I also examined the impact of sublethal pesticide exposure on molecular biomarkers before and after exposure, using oxidative stress biomarkers, protein carbonyl and DNA damage (8-OHdG) (chapter 4) as well as relative telomere length (rTL) (chapter 5).I found that at study site 1 (chapter 2), where lizards were exposed to pesticides via oral gavage, that temperature and fipronil sulfone levels significantly influenced lizard activity in the morning period of movement, where fipronil-treated individuals moved at least 49% less than fenitrothion-treated and control lizards. This was detected from 7 days after dosing through to the end of the experiment at post 28 days. Physiological measures did not change significantly before or after exposure to both pesticides, however, other indicators showed evidence of exposure which remained for the entirety of our monitoring period. On average, cholinesterase inhibition was still > 30% in fenitrothion-treated compared to control lizards at the end of 4 weeks, and fipronil sulfone blood residues remained at 0.219 pg/mL. Comparing this to lizards exposed to ULV aerial spray at study site 2 (chapter 3), fipronil-treated lizards again showed significant changes in activity measures. Interestingly, I found that higher levels of fipronil sulfone in the blood of fipronil-treated individuals correlated to significantly higher activity levels. Fenitrothion and control groups both consistently saw a decrease of up to 30 - 45% in activity over the experiment, where the fipronil group saw a 51% increase in activity between post 7 d and post 14 d. Results also showed that SBMI was not impacted by pesticide treatment but significantly influenced by sex, as well as the number to ticks present on P. vitticeps. Despite persistent depression in ChE (P. vitticeps, which has the potential to modify feeding, reproductive, and predator evasion behaviours. Persistence of both pesticides in the blood of all treatment lizards throughout both field experiments indicate lizards are unable to clear these toxins within 14 days - 28 days post exposure. This may be significant for compounding exposure and latent toxicity.My findings surrounding molecular-based impacts of exposure complemented the behaviour and physiology results to form a comprehensive view on how these pesticides are influencing the biology and ecology of P. vitticeps. In my use of oxidative stress biomarkers of exposure (chapter 4) results suggested no statistically significant treatment effect of either pesticide on parameters measured, however, 8-OHdG levels decreased by >45% for both pesticide treatment groups and not controls. Protein carbonyl levels showed a high degree of individual variation that proved more influential than pesticide exposure itself. My findings on relative telomere length (rTL) changes build upon my oxidative stress results indicating that impacts of sublethal fenitrothion exposure are only detected when utilising molecular-based biomarkers of exposure. Results demonstrate a significant relationship between haemoglobin (Hb) levels and rTL aside from treatment effect. There was no significant treatment effect on rTL or 8-OHdG levels over time, however effect size was large with indication of impact. Fenitrothion-treated lizards saw an average decrease of 46% in 8-OHdG levels and increase of 42% in rTL over the experiment which is of potential biological importance. Fipronil-treated lizards on the other hand saw an average decrease of 25% in 8-OHdG levels and a 6% increase in rTL. Both markers showed negligible change before and after exposure for control lizards. Highlighted in the collective findings of this thesis is the importance of using a specific set of biomarkers of exposure dependent on the type of pesticide you are investigating. Fipronil impacts were only detected using behavioural markers whereas fenitrothion impacts were only detected using molecular markers, combined with blood biomarkers of exposure and physiology across both pesticide treatments. Overall, my thesis provides novel insights into the impacts that widely usedpesticides have on a widespread lizard species in a field-based and ecologically relevant setting.Further, I highlight the susceptibility that reptiles have to a selection of common pesticides andthe inherent need for higher prominence in wildlife ecotoxicological research to inform riskassessments formulated by regulatory bodies and conservation policy.</p
Transvaginal mesh surgery in Australia: The epistemic environment for evaluation of low rate, severe adverse events following innovative surgical procedures
No full textBackground: Stress urine incontinence and pelvic organ prolapse are two common medical conditions associated with pelvic floor dysfunction. These conditions cause significant health issues for women. Although they may not typically be considered ‘severe’ conditions, they can have a significant negative impact on a woman’s quality of life. Various surgical and non-surgical options have been introduced into practice to treat these conditions. Transvaginal mesh surgery was introduced as an innovative surgical treatment option for stress urine incontinence and/or pelvic organ prolapse in women, in 1996. This is believed to have benefited a majority of women undergoing the procedure. However, years after rapid adoption of transvaginal mesh surgery into practice, it emerged that adverse events associated with this surgery, while uncommon, were potentially severe. Advances and innovation in surgery have contributed to significant progress in the healthcare industry’s capacity to provide quality care and improve outcomes. However, such advances have also sometimes generated significant ethical challenges. Transvaginal mesh surgery is such a case: an innovative surgical treatment that raised ethical challenges in surgical practice. Thus, transvaginal mesh provides an instructive example to support recognition and re-evaluation of the ethical issues faced in the surgical field.Methods: To understand use of transvaginal mesh in Australia, and the epistemic environment for evaluation of low rate, severe adverse events following this innovative surgical procedure, I conducted empirical research to produce a thesis by compilation. I used two theoretical resources for my research: approaches from quality improvement and patient safety, and approaches from feminist bioethics. I drew evidence from the clinical peer reviewed literature, Australian print and online media, and public domain submissions and statements made to an Australian Senate Inquiry in 2017. These sources existed in the public domain, but had not been used in a systematic way to understand women’s experiences or the events that led to these experiences. I undertook qualitative analyses of data from these sources to produce my findings.Findings: The clinical literature presented transvaginal mesh surgery as a successful treatment option, with a low rate of associated adverse events overall. It was less likely to provide adequate and accurate evidence of the number of associated harms, and contained almost no evidence of the implications of these adverse events on women’s lives. The literature was highly dependent on experts’ knowledge and expertise to recognise and highlight positive and negative outcomes associated with transvaginal mesh.Women’s experience and perspectives were not only excluded from the clinical literature. In clinical practice settings, the negative outcomes women reported were also dismissed, de-emphasised, or considered outweighed by reported positive outcomes. This suggests a break in the feedback loop to knowledge. This break led to affected women experiencing epistemic injustice, further contributing to their suffering and compounding the harms caused. When affected women reported experiences that were epistemologically incongruent with the views of medical professionals, and regulatory and advisory groups, their testimony was dismissed both from treatment contexts and from the knowledge base. I therefore found that the epistemic injustice experienced not only exacerbated the harms caused by these newly innovative surgical procedures, but also created a gap in the epistemic environment for these procedures.After almost two decades, emerging evidence of harms raised multiple questions regarding ethical challenges in the use of such innovative procedures, and the strategies in place to ensure patient safety and quality of care. Widespread healthcare system failures in the case of transvaginal mesh prompted the creation of major politico-legal movements of women and their supporters worldwide. In Australia, this created a hook to shift news media reporting about transvaginal mesh. The news media then played a significant role in redressing women's experienced epistemic injustice, including by amplifying previously ignored evidence of harm. This created an opportunity for previously unreported suffering to be revealed to powerful actors, in settings beyond the immediate control and epistemic authority of healthcare stakeholders, validating women's testimony and creating new hermeneutic resources for understanding transvaginal mesh. These developments provided women with greater epistemic justice, giving their testimony privileged epistemic status, such that it was considered by other actors.In the Australian healthcare system, clinical perspectives have historically been privileged over patient perspectives in evaluating transvaginal mesh outcomes. This allowed micro-level actors to dismiss women’s lived experience, such that women’s accounts of harm had insufficient or no weight at meso and macro levels. The dismissal of reported negative outcomes was rationalised by professional actors in two ways. Firstly, by contesting the significance of, or evidence for, associated harms. This contestation led to a testimonial quieting of affected women’s interests. Secondly, by denying or minimising conflict of interest. The close and normalised relationship between treating professionals and device manufacturers may have created a conflicted environment for practice and for prioritising patients’ interests. Ultimately, that led to professionals’ advocacy regarding policy solutions emphasising incremental change, aiming to retain these procedures in practice.Quality and patient safety theories are used to regulate healthcare systems to reduce harms, maximise quality of care, and optimise health outcomes. These theories and strategies acknowledge a need for innovation and advancement in practice, but tend not to be prescriptive regarding use of innovations. I connected quality improvement and patient safety theories to surgical ethics, especially in the context of innovative surgical procedures. I argue that the case of transvaginal mesh surgery illustrates that these two normative approaches should not be separate, but instead should be integrated, with implications for both disciplines.Conclusion: Although quality and patient safety standards often include some rudimentary ethical considerations, such as requiring informed consent for procedures, this enters quality and safety through professional standards rather than a deep consideration of clinical ethics. More deeply incorporating ethical considerations, including regarding patient harms, epistemic injustice, and conflict of interest, would strengthen quality and patient safety by providing greater conceptual depth and better thinking tools to help address practice dilemmas. Simultaneously, clinical ethics could be strengthened through a stronger connection to quality and patient safety frameworks, which include detailed and practical thinking about patient harms, regardless of their prevalence, preventability or severity, the things that matter to patients, including their experiences of harm, and what should count as adequate benefit. I conclude that recognising and acknowledging patients’ epistemic status across all three levels of the health care system, including in processes that govern innovative surgical procedures in practice, is an essential strategy to recognise harms when they occur, and ensure they receive an adequate response.</p
From Metaphysics to Politics: A Materialist Feminist Critique of Enactive Ethics
No full textThe enactive approach’s radical and unorthodox conception of cognition as interactive, intersubjective, deeply affective, and non-representational allows it to open up new avenues for investigating many intractable philosophical questions, including questions usually related to ethics. The overarching goal of this thesis is to situate enactive ethics within a materialist feminist analysis and interrogate whether enactive ethics is living up to its ambitions in practice.In the first chapter, I trace the commitments of cognitivist approaches to cognition with liberal feminist political goals and practices, and contrast these with embodied and enactive approaches to cognition with materialist feminist political goals and practices. I articulate these affinities to show the ways that our metaphysics of mind should (and indeed already does) inflect our political methodologies. In the second chapter, I offer up work in implicit bias studies as a means of putting meat on the bones of this claim. From here, I argue that although enactive ethics’ focus on interactivity, affectivity, and intersubjectivity has many positive dimensions, there are significant consequences to this focus that have not yet been seriously considered. For example, in the third chapter, I show that enactive ethics’ focus on interaction runs the risk of reifying interaction at the cost of the safety and flourishing of the marginalized. In the fourth and fifth chapters, I problematize the implicit pacifism that runs through enactive ethics; if enactive ethics is a legitimate bedfellow of materialist feminist political organizing, and hopes to be useful in helping secure feminist, anti-racist, decolonial social transformation, it must neither ignore nor foreclose the sometimes unsavory political tactics used by marginalized groups. I show that in its current formulation, enactive ethics cannot appropriately appraise political violence, and that this should be considered problematic. Finally, I offer up potential problems of the organism-based politics of enactive ethics and point to future directions of research where this may be taken up, including environmental ethics and digital ethics.</p
Radiobiological Modelling of Dose Response and Normal-Tissue Complication for Novel Radiopharmaceutical Therapy Cocktails
No full textIn radiopharmaceutical therapy (RPT), cocktails of radionuclides have the potential to target a larger range of metastatic lesion sizes compared to single radionuclides. Given the number of radionuclides becoming clinically available, there has been a renewed interest in the investigation of the use of radionuclide cocktails for RPT.The aim of this study was to provide a radiobiological framework to investigate the therapeutic efficacy of radionuclide cocktails. Dose response in terms of biological effective dose (BED), tumour control probability (TCP) and normal-tissue complication was modelled for cocktails of radionuclides of recent interest in the field of RPT (67Cu, 166Ho, 188Re and 225Ac), in addition to the more conventional cocktail radionuclides 90Y and 177Lu.Uniform distribution of radionuclide cocktails have been simulated in the Geant4 Monte Carlo toolkit with variable initial activity concentration ratios. The BED was modified to include the absorbed dose-rate effects from the simultaneous administration of 2 radionuclides and TCP values in solid tumours ranging from 100 μm to 2.5 cm were estimated. The equivalent uniform equieffective dose (EUEQDX) to surrounding tissue was assessed up to a distance 3 times the lesion radius for evaluation of normal-tissue complication.The theoretical benefits of cocktails for treatment of metastatic disease are demonstrated with a greater range of tumour sizes experiencing a higher TCP when exposed to a combination of radionuclides rather than either radionuclide alone. When selecting appropriate radionuclide combinations, the half-life and range of emissions must be considered carefully, with most optimal results seen in this study after combining 177Lu with 166Ho or 225Ac. Care must also be taken with the ratio of administered radionuclide activity concentrations, as the TCP is shown to vary significantly in response to these ratios. In any combination considered in this study the surrounding normal-tissue EUEQD2 equivalent to a 2 Gy external beam radiotherapy (EBRT) regime did not exceed 5.3 Gy.This modelling study provides a framework for the assessment of dose response and normal-tissue toxicity in the use of novel radionuclide cocktails in RPT. The approach proposed in this work can be used, in the future, to tailor the treatment of metastatic lesions for individual patients by supporting the selection of cocktail of radionuclides of given composition, when appropriate, over single radionuclides.</p
Dose Quantification in Neutron Capture Enhanced Particle Therapy
No full textThe main aim of radiotherapy is to target tumour cells while limiting dose to healthy tissue. Particle therapy is ideal for this purpose, with a low entrance dose and a characteristic Bragg Peak at the end of the ion path for high dose inside the target.Charged particles can interact in matter through a variety of ways, including via nuclear inelastic collisions with atoms in the beam path; secondary particle generation in this process leads to the production of fragments such as neutrons. These neutrons, through the tumour uptake of high neutron capture cross-section isotopes such as 10B or 157Gd, can be captured to deliver additional dose to the target. This is the main principle of Neutron Capture Enhanced Particle Therapy (NCEPT). However, the implementation of such a modality requires extensive research into methods of accurate dose quantification, for both the primary ion dose and additional neutron capture dose.One possibility is through the detection of characteristic photons which are emitted as a product of the neutron capture interactions; for 10B this occurs at 478 keV, while a range of photons are produced for 157Gd including the higher energy photons at 6.75 MeV and 7.94 MeV. As these photons are only emitted during neutron capture, their detection indicates that the interaction has occurred and hence there is additional dose deposition.The detection of photons due to neutron capture is limited by false positive counts that occur within the same energy and temporal windows, but were created by other processes (including Compton scattered photons). The discrimination of neutron capture photons from these other detected counts is essential for the application of a prompt gamma detection based system for NCEPT; this can be through various methods, including the implementation of energy and timing windows, or they may be reduced through shielding.This Thesis details the initial stages of the development of a dose quantification system in NCEPT through both simulation and experimental methods. The characteristics of photon and neutron emission following 12C and 4He ion therapy are studied, with timing windows for the detection of prompt gamma and neutron capture photons identified for potential application in neutron capture discrimination. A window of 12 ns - 104 ns is recommended, with prompt gamma photons arriving at the detector prior to this time and positron annihilation photons arriving after 104 ns.The BeNEdiCTE detection module is investigated for its feasibility as a prototype scintillation system and its ability to distinguish an increase in the 478 keV signal with the addition of 10B. This was identified for 12C and 4He ion beams, with the first experimental demonstration of neutron capture photon detector during heavy ion therapy detailed here. For comparison to the heavier ion beams and consideration of its feasibility, an experimental study was also conducted with a proton beam.Additionally, the ability of the detection system to measure differences in the signal with variation in position and concentration was considered. The simulated detector was able to detect a change in concentration down to the order of 100 ppm, however for concentrations below this, a multi-head detection system is suggested.Finally, a shielding optimisation study was performed in which it was determined that in a low-background environment it is preferable to avoid shielding of the detector crystal. Alternatively, for high neutron background environments or in the presence of boroncontaining electronics (such as printed circuit boards) during 10B NCEPT, a small layer of shielding such as 1 mm Gd2O3 is suggested.Overall, it has been demonstrated that dose quantification during NCEPT using a neutron capture detection system is both feasible and essential for the clinical implementation of this modality.</p