Griffith Research Online
GRO delivers free online full-text versions of journal articles, conference papers, and more, where this is possible with the appropriate permissions of copyright owners. GRO increases the impact and influence of Griffith research and scholarship by ensuring it is visible, discoverable and accessible via search engines like Google and discovery services like the National Library’s Trove.
Communities in Griffith Research Repository
Select a community to browse its collections.
Recent Submissions
This program of research examines the relationship between young drivers' views of police legitimacy and their driving intentions and behaviours on the road. Police legitimacy refers to the public's perception of the police as a trustworthy, fair and effective authority whose actions are morally aligned with societal values (Tankebe et al., 2016). In the context of road safety, this program of research aims to determine if the public views police as legitimate and are more likely to comply with road rules, thus reducing risky driving behaviours that often lead to crashes, and enhancing overall road safety. The central aim of this research is to explore how these views of police legitimacy affect young driver' compliance with road rules and their willingness to engage in risky driving behaviours, contributing to their over-representation in serious and fatal crashes. This research employs a mixed-methods approach, incorporating longitudinal, experimental, and qualitative methodologies to provide a comprehensive exploration and understanding of factors that have not yet been considered in the research that may influence young driver behaviour and overall safety on the roads. The primary objectives of this research are fourfold. First, I assessed the immediate impact of a police-led school-based road safety education program (the LAW program) on young drivers' views of police legitimacy and self-reported driving behaviour. Second, I investigated whether the presence of uniformed police officers during educational road safety programs, such as the LAW program, significantly influences young drivers' views of police legitimacy when compared with plain-clothed officers. Third, I developed and evaluated a co-designed digital road safety intervention aimed at reinforcing safe driving behaviours and improving views of police legitimacy. Finally, I examined changes in young drivers' views of police legitimacy and self-reported traffic offences over time to understand the longer-term effects of the police-led road safety program and the co-designed digital intervention. This program of research utilises a combination of quantitative and qualitative methods. A quasi-longitudinal design was employed to assess changes in young drivers' views of police legitimacy and their self-reported traffic offences over time. This required surveys to be administered at multiple time points to capture the evolution of these views and behaviours. An experimental trial evaluated the impact of police uniforms on young drivers' views of police legitimacy. Young drivers attended a police-led road safety program delivered by the same police officers in either uniform or plain clothes, and their views of police legitimacy and driving intentions were measured. A digital road safety intervention was developed using a collaborative design process involving both road safety experts and young drivers. The intervention aimed to deliver engaging and effective, evidence-based road safety messages tailored to the target audience. The intervention was approximately 4 minutes long. The effectiveness of the digital intervention was assessed through follow-up surveys conducted three months post-intervention delivery to examine any changes in driving behaviours and views of police legitimacy between those who received the intervention and a comparison group. The key findings of this program of research are significant, both theoretically and practically. Participation in the LAW program led to improvements in young drivers' views of police legitimacy, which were significantly associated with lower intentions to offend. The presence of uniformed police officers during the LAW program had a greater positive impact on young drivers' views of police legitimacy and intentions to comply with traffic laws compared to when the same officers presented the program in plain clothes. While the co-designed digital intervention was well-received at the design stage and had input from both young drivers and road safety experts, it did not lead to significant changes in self-reported driving behaviours and offending. However, longitudinally, views of police legitimacy remained a significant predictor of young driver behaviours. The quasi-longitudinal study revealed that initial positive views of police legitimacy following the LAW program decayed over time, highlighting the need for sustained positive interactions between police and young drivers to maintain these views. [...]
This thesis examines the impact of board gender diversity as a governance mechanism on different corporate outcomes: cash holdings, stock liquidity, and green financing, and on the interlink between stock liquidity and cash holdings, using four unique studies. Several factors motivate an investigation of board gender diversity effects, using a worldwide sample: i) global call to improve board gender diversity with quotas and voluntary initiatives; ii) rising global uncertainties such as the COVID-19 pandemic that require resilient boards; iii) variations in the institutional environment across international economies; iv) the paucity of existing literature in explaining the effects of board gender diversity from a global and holistic perspective. The first study examines the relationship between board gender diversity and cash holdings, with an emphasis on the board's behaviour during uncertain times. Drawing from 94,950 firm-year observations across 49 countries from 2006 to 2021, the study finds that board gender diversity significantly reduces firms' cash holdings and excess cash worldwide. Firms increasingly face disruptive surprises such as the COVID-19 pandemic; hence, it is important to examine whether gender-diverse boards are resilient in reducing agency problems associated with cash holdings when confronted with higher levels of uncertainty. This study provides fresh insights into the resilient attributes of gender-diverse boards in addressing these agency problems. Further, the study discerns the effects of the institutional environment, economic development, and national culture on the efficacy of gender-diverse boards. Findings are robust to endogeneity concerns, regulatory effects, and sample bias. This study contributes to the cash holdings and firm's resilience literature with insights into board gender diversity effects and cross-country variability and gender-quota effects. The rise of unprecedented uncertainties on a global scale demands more resilient firms to protect the interests of stakeholders. Hence, the second study investigates whether gender-diverse firms are resilient in maintaining stock liquidity during uncertain times, using a worldwide sample of 49 countries with 95,730 firm-year observations. Results show that gender-diverse boards improve stock liquidity, benefiting the stockholders. Of note during the pandemic, stock liquidity decreased for firms with less gender-diverse boards, but increased for firms with greater gender diversity. The study further provides evidence for the positive effects of mandatory gender quotas on stock liquidity, and the effects of institutional environment and national culture on gender diversity-stock liquidity association. This study contributes to the stock liquidity literature with board gender diversity effects during uncertain times, effects of gender-quotas and factors affecting cross-country variability. Financing for climate change initiatives is on the rise. The third study investigates whether board diversity drives green financing using cross-country data. Findings show that diverse boards in terms of gender and generalist skills improve the level of green financing. Moreover, the study examines two mechanisms that explain the positive association between board diversity and green financing. The findings show that diverse boards increase ESG ratings and reduce default risk, leading to higher levels of green financing. Further, the study provides evidence for the heterogeneity of the board diversity-green financing association with a sustainability-linked compensation policy and attributes of national culture. The study contributes to the literature in several ways. Despite prior literature showing board diversity effects on environmental performance, there is a dearth of studies on how board diversity influences the firm's level of green financing. This study fills this gap using cross-county data. Moreover, this study adds to the literature by providing mechanisms and interaction effects on the positive association between board diversity and green financing. Building on the observations of the first and second studies, the fourth study further examines the interlinks between stock liquidity and cash holdings. The purpose of this study is to investigate whether investors practise disciplinary trading using the ESG scores provided by rating agencies to influence firms' cash holdings. Employing a larger sample of US listed firms, this study finds that stock liquidity acts as a channel between ESG scores and cash holdings. ESG scores carry vital information on the effectiveness of firms' governance and on agency problems. Hence, investors respond to ESG information through stock trading that sends signals to management, resulting in changes in firms' cash holdings. Consequently, investors use stock trading as a mechanism to create the necessary push for insiders to resolve agency problems. The study contributes to the cash holdings and stock liquidity literature with novel evidence on how investors' disciplinary-based trading could influence a firm's behaviour. Overall, this thesis provides evidence of the positive effects of board diversity on different firm outcomes and the ability of stockholders to influence a firm's policies through stock trading to achieve desirable outcomes.
BACKGROUND: Group A streptococci (Strep A) orStreptococcus pyogenes is a major human pathogen causing an estimated 500,000 deaths worldwide each year. Disease can range from mild pharyngitis to more severe infections, such as necrotizing fasciitis, septicemia, and toxic shock syndrome. Untreated, Strep A infection can lead to the serious post streptococcal pathologies of rheumatic fever/rheumatic heart disease and post-streptococcal glomerulonephritis. An effective vaccine against Strep A would have great benefits worldwide. Here, we test two products, J8 and p17-both peptide derivatives of a highly conserved region in the M protein, in combination with the protein subunit K4S2 of SpyCEP, an IL-8 protease associated with neutrophil chemoattraction. Each peptide is individually conjugated to cross reacting material (CRM197), and the conjugated peptide vaccines are abbreviated as J8-K4S2 or p17-K4S2. METHODS: This single-site phase I, two-stage clinical trial in Edmonton, Alberta, Canada, aims to recruit a total of 30 healthy volunteers, aged 18-45 years, without any evidence of pre-existing valvular heart disease. The trial is divided into the initial unblinded safety test dose stage (stage 1) and the randomized, double-blinded, controlled trial stage (stage 2). Stage 1 will recruit 10 volunteers-5 each to receive either J8-K4S2 or p17-K4S2 in an unblinded, staggered fashion, whereby volunteers are dosed with intentional spacing of at least 2 days in between doses to monitor for any immediate side effects before dosing the next. Once all 5 volunteers have received 3 doses of the first test vaccine, a similar process will follow for the second test vaccine. Once safety is established in stage 1, we will proceed to stage 2, which will recruit 20 volunteers to our 3-arm randomized controlled trial (RCT), receiving either of the trial vaccines, J8-K4S2 or p17-K4S2, or comparator (rabies) vaccine. All product dosing will be at 0, 3, and 6 weeks. The primary outcome is vaccine safety; the secondary outcome is immunogenicity and comparative analyses of the different vaccine regimens. DISCUSSION: This Strep A vaccine clinical trial aims to investigate safety and immunogenicity of two novel conjugated peptide-based vaccines, J8-KS42 and p*17-K4S2. If one or both vaccine products demonstrate favorable primary and secondary outcomes, the product(s) will move into phase II and III studies. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04882514. Registered on 2021-05-12, https://clinicaltrials.gov/study/NCT04882514 .
Background Maintaining the quality and integrity of student assessments, especially in professional fields like nursing, is critical. Managing moderation processes across large teams poses social and logistical challenges, further complicated by varying quality and clarity of institutional guidelines. Systematic reviews on moderation practices in higher education are scarce. Objectives This integrative review critically analyses moderation practices in the literature and evaluates the quality of published institutional guidelines to support faculty in enhancing moderation practice. Method An integrative review, guided by research questions, was used to facilitate data extraction. Searches in ERIC, Web of Science, and A Plus Education Informit databases focused on higher education papers published in English between 2008 and 2023. Of 552 studies screened, 19 were included in the final review. The quality of the included studies was appraised using the appropriate Critical Appraisal Skills Programme (CASP) checklists, tailored to the specific research designs. Institutional guidelines were identified via web searches and evaluated using a tool based on elements of a recognised clinical practice guideline assessment tool. Results The review included 19 peer-reviewed studies and 27 institutional guidelines. Of the studies, 14 were qualitative, 2 quantitative, 2 mixed-methods, and 1 a guideline review, with most focused on Australian higher education. Key findings indicate the importance of collaborative moderation processes, in establishing shared standards. The studies highlighted the need for clear marking guides, ongoing training, pre-teaching discussions and adequate resourcing. The guideline evaluation revealed variability in quality, with frequent deficiencies in stakeholder involvement and development rigour. Some guidelines offered practical implementation tools. Conclusions Moderation practices in higher education are complex and resource-intensive, particularly for large teams. Effective moderation is crucial for maintaining assessment quality and integrity. Consensus moderation, through collaboration among markers, tutors, and assessors, supports shared standards via dialogue, calibration, and consensus building. Improving moderation practices requires evidence-based guidelines, a focus on consensus-building, sufficient resources, and ongoing professional development.
Head and neck malignancy, and in particular squamous cell carcinoma (SCC), is responsible for a significant disease burden globally. Head and neck SCC (HNSCC) epidemiology has changed over the past 40 years, with human papillomavirus infection now demonstrated to be a major causative factor in rising rates of oral cavity and oropharyngeal mucosal SCC. The lack of an optimal in vitro model system to accurately recapitulate in vivo responses to therapy in HNSCC remains a challenge. The development of tumour-derived three-dimensional cultures known as tumour organoids, or tumoroids, has provided for improved modelling of the tumour microenvironment through simulation of important characteristics such as tumour hypoxia, cell-cell interactions, and nutrient diffusion characteristics. In turn, this has revealed broad promise in translational research towards the characterisation of cancer therapy responses within the domain of precision medicine. Current methods of tumoroid development utilise Matrigel® and CultrexTM Basement Membrane Extract 2 - two common proprietary murine-derived hydrogels containing extracellular matrix proteins. While useful for facilitating cell-matrix interactions and providing a scaffold for three-dimensional cell growth and organisation, these have notable limitations. Hydrogels are temperature sensitive and liable to solidification which can impede the addition and removal from supernatant of chemotherapeutic agents, secreted vesicles, and growth factors. Their murine origin and absence of human immune cells are also inherently suboptimal in creating the correct substrate for the culture and modelling of human cancers. There exists a need for further optimisation of these organotypic models as a platform for novel drug discovery and drug testing. A protocol that reliably and reproducibly facilitates the propagation of tumoroids from a heterogeneous patient-derived tumour specimens will be invaluable in achieving this aim. A novel hydrogel-free method of establishing in vitro tumoroid cultures has been subject to experimentation in colorectal malignancy but not in head and neck malignancy. The absence of a hydrogel provides for the de novo synthesis of extracellular matrix native to the tumour and self-organisation of cells within this scaffold through the use of ultralow attachment plates. This model demonstrates similar structural and physiological properties to native tissue, whilst enabling more accurate biomimicry of the tumour microenvironment for drug testing. We applied a novel hydrogel-free method to establish an end-to-end protocol for the development of HNSCC tumoroids and compared them quantitatively and qualitatively to existing hydrogel-based methods using CultrexTM and Matrigel®. A total of 26 successful tumoroid lines were created using the three culture methods from 27 patient-derived tumour samples, representing the highest rate of success in the literature. These patient-derived tissues encompassed the breadth of the upper aerodigestive tract from a broad, heterogeneous demographic. Tumoroids developed without hydrogels demonstrated significantly higher logarithmic growth over a 14-day incubation period compared to their hydrogel-based counterparts. Importantly, increased cell proliferation was observed in proportion to lower initial cell counts in the hydrogel-free model, further highlighting its ability to replicate in vivo cancers, which typically start with small numbers of cells. Further characterisation of the tumoroids with static interval imaging and timelapse imaging provided opportunities for qualitative assessment. Dominant tumoroid morphologies of heterogenous size and density were viewed under low magnification and observed to increase in size exponentially with static imaging. However, the timelapse imaging experiment was not successful secondary to a number of logistical, hardware and so\ware issues experienced. Immunofluorescence of key cell elements including pancytokeratin and cell-surface vimentin confirmed the presence of tumoroid organisation, diseased squamous epithelium, and de novo synthesis of cytoskeletal elements. The presence of tumour hypoxia is a key phenomenon of the tumour microenvironment and was demonstrated in one of the hydrogel-free tumoroids. An assay of metabolic activity demonstrated dose-dependent responses to chemotherapeuGc agents used in treatment of HNSCC. These were independent of the culture methods, indicating the utility of the tumoroids in in vitro drug testing. This study iterates our understanding of tumour organoids in HNSCC and at large, by introducing hydrogel-free culture as a novel method achieving greater cell yield and closer recapitulation of the tumour microenvironment. The results are promising for groups looking to replicate the method at scale and serve as a gateway to furthering the application of this work to precision medicine.