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Welding health hazards
No full textEmpirical thesis.Bibliography: pages 78-79.1. Introduction -- 2. Background and related work -- 3. Experimental procedure -- 4. Data analysis -- 5. Results -- 6. Discussion -- 7. Conclusion -- 8. Future work.Welding is one of the most widely used processes for joining metal together. There is a diversity of welding methods that are used in different working conditions. Welding could be extremely harmful for human health as it emits toxic gases and small respirable particulates that are also called welding fumes. The aim of this project is the assessment of welding fumes. Achieving this aim requires identifying the hazard, assessing the risk, and minimising the risk through proper control methods. To identify the hazard, air sampling techniques will be used to capture gases and welding fumes. Four welding processes will be carried on for the fumes to be extracted and analysed. TIG, MIG, SMAW and OXY welding and data collection will be conducted through air sampling techniques. Based on the results a recommendation will be shown of the welding process and the welding rod material in terms of the least health hazards risk created. The effect of both the extraction distance and flow rate on particle size distribution and morphology was also covered.Mode of access: World wide web.1 online resource (80 pages illustrations (some colour)
Internet of Things (IoT) enabled actuator for sensing application
No full textEmpirical thesis.Bibliography: pages 65-66.1. Abbreviations -- 2. Introduction -- 3. Background and related work -- 4. System development -- 5. Remote application system and deployment -- 6. Results and analysis -- 7. Conclusions -- 8. Future work -- Appendices -- Bibliography.Time required to travel and collect water samples is time-consuming where the collection of these samples from remote locations can drastically impact the water quality. Examples of these impacts include fluctuating temperatures and settling of the samples. Quality will diminish and inaccurate measurements will conceive invalid data relative to the actual water source. The recent innovation of IoT enabled sensors and actuators throughout recent years have proven beneficial to society. Here, we examine the integration of an IoT enabled microcontroller unit with a nitrate sensor to readily test and send a live data feed of the nitrate content of a remote water source to benefit the surrounding community dependent of this water source.Mode of access: World wide web.1 online resource (xv, 66 pages colour illustrations
Evaluation of the biophysical characteristics of upconversion nanoparticle-based nano-bio hybrids for blood-brain barrier crossing
No full textEmpirical thesis.Bibliography: pages 140-150.Chapter 1. Introduction -- Chapter 2. Protocol development and optimization -- Chapter 3. A versatile upconversion surface evaluation platform for bio-nano surface selection for the nervous system -- Chapter 4. Evaluation of the effect of shape upon endocytosis of transferrin-coated UCNPs, and their ability to cross the blood-brain barrier -- Chapter 5. The effect of modifying the aspect ratio of PEGylated UCNPs upon their cellular uptake -- Chapter 6. Summary and future scope.Brain diseases including Alzheimer’s disease, Huntington’s disease and amyotrophic lateral sclerosis (ALS) are fatal diseases without effective treatments. In past decades, some potentially effective therapeutics have been developed and demonstrated promising effects for brain diseases in pre-clinical cell culture and animal model evaluation. However, most of these developed drugs cannot reach the brain for therapy due to their inability to cross the blood-brain barrier (BBB). To overcome the BBB, nanotechnology is emerging as a promising approach to mediate and increase BBB penetration of drugs to the specific site of the brain. However, the efficiency of nanoparticle-based BBB penetration is still very low (<1%), with much to learn about how the biophysical properties of nanoparticles such as which size, surface, shape of nanoparticles facilitate BBB penetration. This project takes advantage of the specific properties of upconversion nanoparticles (UCNPs) including low auto-fluorescence, non-photobleaching, deep tissue penetration and adjustable size and shape, to develop a versatile platform to systematically evaluate the effects of nanoparticle surface, shape on BBB crossing in vitro and in vivo for future construction of multifunctional nano-carrier for theranostic applications in neurodegenerative diseases.In the first chapter, this thesis introduced the BBB and currently understood mechanisms of BBB penetration, and reviewed recent advances in nanoparticle-based BBB penetration strategies and approaches for brain disease therapy.In the second chapter, I described the key experimental methods that were developed and optimized for use in this project. Typically, the UCNPs employed in this project were fabricated via modified and optimized standard protocols for specific application as required. Importantly, the approaches of zebrafish imaging and microinjection were developed brand new in this project.In the third chapter, a UCNPs-based evaluation platform was synthesized for bio-nano surface selection in vitro and in vivo to systemically evaluate the suitability of various surface modifications for theranostic applications in neurodegenerative diseases. First, high lanthanide-doped UCNPs was designed, which provide strong tissue penetrable emission at 800nm. Then, these as-prepared UCNPs were further modified with four popular surfaces (OA-free, DNA-modified, silica coated and PEG-COOH capped) for comparison. The result showed that PEG-COOH performed superior cell internalization and excellent uptake capability into spinal motor neurons in zebrafish. Our work provides a versatile strategy via systemically surface evaluation for future construction of multifunctional nano-systems for therapeutic delivery to the central nervous system.In the fourth chapter, the effect of nanoparticle shape upon cell uptake and BBB penetration was further studied in vivo and in vitro. Firstly, a series of UCNPs with different shapes (including spherical, rod, disk and dumbbell) which retained similar size with each other were fabricated. Thereafter, these UCNPs were further modified with transferrin to make them specifically target the BBB. The results revealed that rod - shaped Tf - UCNPs displayed excellent brain endothelial cell uptake and brain accumulation in living zebrafish. Importantly, this study provides promising morphology information for design of efficient nano-carriers to cross the BBB for treatment of brain disease.In the fifth chapter, the optimal aspect ratio (AR, width/length) of upconversion nanorods (UCNRs) for BBB penetration were investigated. A series of high-lanthanide doped UCNRs with various aspect ratios (1, 2, 3 and 4) were developed. Then those UCNRs were further modified with PEG-COOH, since PEG-COOH modification was found to have superior cell internalization and excellent uptake capability for central nervous system from the results of Chapter 3. It was found that the aspect ratio of 2 PEGylated UCNRs provides the best cell uptake efficiency in neuron cells (NSC-34 neuron like cells, primary neuron cells and glial cells) compared to nanoparticles with other aspect ratios. This study demonstrates that aspect ratio has a significant influence upon cell uptake of neuron cells, which provides an alternative opportunity for further design of nanoparticle-based therapies for drug delivery of nanoparticles into the brain.In the sixth chapter, result of this thesis was summarized and perspective for the future applications for UCNPs-based drug delivery across BBB for CNS diseases was presented. To summarise, a transferrin-coated UCNRs with respect ratio of 2 was investigated as a potential drug carrier for treatment of neurodegenerative disease. These nanoparticles were capable of readily crossing the BBB and accumulating within the brains of living zebrafish, highlighting the therapeutic potential of this specific nanoparticle design. Overall, this study demonstrated a novel method to identify preferable biophysical characteristics of upconversion nanoparticle-based nano-bio hybrids to increase targeted nanoparticle accumulation in the brain.Mode of access: World wide web1 online resource (xviii, 174 pages) colour illustration
Explanatory framework for well-being theories: systematic, comprehensive, persistent
No full textTheoretical thesis.Bibliography: pages 81-95.Chapter 1. Systems theory : background and terminology -- Chapter 2. A system framework for building theories of well-being -- Chapter 3. The engine of well-being : a critical evaluation -- Chapter 4. The four qualities of life : a critical evaluation -- Chapter 5. Discussion, limitations and future research -- Reference list -- Appendices.Well-being is a broad construct widely acknowledged for being multidimensional, multidisciplinary and dynamic in nature. There is a growing need for a framework to assist in building comprehensive theories providing an explanation for well-being outcomes. In this thesis, a systems approach to well-being theories is proposed following research traditions in personality and organizational psychology and other disciplines. In these latter domains, a systems approach has provided many benefits including increased understanding of complex phenomena and theory formalization. Using conceptual analysis, systems theory is applied as a framework to develop five principles for building and evaluating theories of well-being: a well-being system framework. The principles are then applied to evaluate two integrative well-being frameworks: the engine of well-being (Jayawickreme, Forgeard, & Seligman, 2012) and the four qualities of life (Veenhoven, 2000). The theoretical contribution of this thesis is an explanatory framework aiming to guide theory development by suggesting components that a theory requires to explain well-being. The well-being system framework aims to open new avenues for research using a systems theory approach to assist in developing comprehensive models of well-being.Mode of access: World wide web1 online resource (v, 105 pages) diagrams, table
Multifarious methods for enhancement of luminescence in rare earth ion-doped upconversion nanocrystals
No full textThesis by publication.Bibliography: pages 177-181.Chapter 1. Introduction -- Chapter 2. Literature survey -- Chapter 3. Probing the interior crystal quality in the development of more efficient and smaller upconversion nanoparticles -- Chapter 4. Optimal sensitizer concentration in single upconversion nanocrystals -- Chapter 5. Uniformity and application of UCNCs in enhancing super resolution nanoscopy -- Chapter 6. Summary and future work -- References.Upconversion nanocrystals (UCNCs) have become a sought-after delivery system for advanced biomedical and photonics applications since they have the unique ability to convert low energy infrared photons into high-energy visible and ultraviolet photons. In this work, the author has developed a number of approaches to the fabrication of UCNCs that are small in size and so are of much use in the field of biology and medicine. Since a long-pursued goal for UCNCs is the further enhancement of their upconversion efficiency and the generation of a stronger emission, the author also describes new procedures for the fabrication of particles that possess enhanced efficiency in their upconversion luminescence.To achieve the two aims, the author first investigated the nature of the interior crystal quality of these particles and how to enhance it. Experiments that formed part of this work demonstrated that smaller and more efficient UCNCs can be formed with improved interior crystal quality. In parallel to this line of investigation, the author also demonstrated the importance of controlling the NaYF4 transit stage from cubic phase to hexagonal phase. Following this, an efficient method for synthesizing sub-10nm UCNCs, and then fabricating a novel sandwich structure, was developed. The sandwich structure nanocrystal can realize size-tunable and doped maximum sensitizer ions. The author also found that the particles, when enclosed by an inert shell, were able to achieve minimal surface quenching as well. Finally, the author shows that a photon-avalanche-like effect plays the key role in bringing down the intensity requirement for stimulated emission depletion with high Tm3+ ions doped nanocrystals s. The sensitizer ions present as a radial gradient distribute from the core to the surface. This kind of UCNCs offer efficient optical switching with saturation intensity at low power and provides a large contrast to conventional fluorescent probes used for super resolution stimulated emission depletion (STED) nanoscopy.The three major results are presented in four publications. The author presents a summary and prospect chapter at the end as well. This thesis provided several good ways to solve the key problems of size-tunable and luminescence enhancement for UCNCs applications. It has profound implications for the upconversion optical property exploration and realizes further bioimaging and biomedical applications.Mode of access: World wide web1 online resource (iv, 181 pages) illustrations (some colour
NSW preschool educational leaders
No full textEmpirical thesis.Running title: NSW preschool educational leaders.Bibliography: pages 93-97.Chapter One. Introduction -- Chapter Two. Literature review -- Chapter Three. Method -- Chapter Four. Findings -- Chapter Five. Discussion -- Chapter Six. Reference list -- Appendices.The requirement for a specific educational leader is relatively new to Australian ECEC settings and complexities have been observed regarding the implementation and purpose of the educational leader role. Previous research on the educational leader role has been limited and rarely included the experiences of educational leaders in preschool services. This mixed method study used the theory of practice architecture as a theoretical and analytical framework to investigate who the educational leaders of NSW preschools are, what they do and what supports them. The findings indicated that preschool educational leaders were experienced and educated. They were rewarded by the professional growth of other educators and challenged by limited time and ambiguous information about the educational leader role. Participants’ practices most frequently included casual talks and sharing research and resources and they found support for their role through training and their own research. Small differences were found in aspects of how directors and teacher educational leaders performed the role. Findings from this study show that if educational leaders are to be effective in improving practice in preschool settings more action is required to support educational leaders to lead and ECEC organisations and policy makers to champion educational leadership.Mode of access: World wide web1 online resource (vi, 131 pages) graphs, table
Narrative and transmedia branding: storytelling in Macy’s Inc. Believe Christmas campaign
No full textTheoretical thesis."Believe in the magic of giving" -- title page.Bibliography: pages 138-155.Introduction -- Assumptions and definitions -- Chapter 1. Literature review -- Chapter 2. Towards transmedia storytelling -- Chapter 3. Case study -- Macy's Inc. Believe campaign -- Chapter 4. Conclusion --Appendices -- Bibliography.Transmedia storytelling techniques have been primarily used by the entertainment industry but have also been applied to the advertising campaigns designed by corporations, a concept known as transmedia branding. Transmedia storytelling requires a narrative to be told over a range of mediums with each working within its own capabilities of communication and interactivity. Meanwhile an all-encompassing storyline is created to keep all the threads within the same story world.The aim of this study is to demonstrate how the narrative potential of campaigns specifically created via transmedia branding techniques is changing the way stories are being communicated and consumed. Previous studies in the use of transmedia branding have concentrated on their effectiveness as an advertising campaign while an analysis of the narrative techniques being employed was missing. Narrative studies into transmedia use have tended to focus on movies or television series that already have an inherent created story world.A critical qualitative analysis has been applied to Macy Inc.’s Believe Christmas campaign to determine how they have created and maintained a nine-year evolving story world across multiple mediums. The study shows how the complexity of audience interactivity challenges the basic narrative concepts of story organisation, presentation and coherence. Discourse and visual analysis was also applied to user responses to discover how and whether they have understood and interpreted the story world being presented to them.Mode of access: World wide web1 online resource (155 pages) colour illustration
Driving and cognitive functioning: does age matter?
No full textEmpirical thesis.Bibliography: pages 60-72.Introduction --- Method -- Results -- Discussion -- References -- Appendices.There is an established relationship in the literature between cognitive functioning and driving performance in older drivers and new evidence suggests that this relationship also exists in younger drivers. Given this, it follows that this relationship may exist for all drivers, however the relationship between cognitive function and driving in drivers in middle adulthood has not yet been examined. This study therefore aims to examine this relationship in drivers in middle adulthood, and thereby fill the gap in the literature. A secondary aim was to apply a neurocognitive model of driving to this driver group. The participants were 88 drivers aged between 24 and 65. Each participant was assessed on a battery of cognitive tests and completed a drive on a driving simulator. Measures of driving performance included speeding, lane deviation, and an overall driving performance score. The results showed new evidence to suggest that overall cognitive function can predict speeding and overall driving performance. There is preliminary evidence to suggest that a neurocognitive model of driving can explain speeding in drivers in middle adulthood. Future research should focus on the development of a comprehensive model to explain driving performance across all ages and across disciplines.Mode of access: World wide web1 online resource (x, 84 pages) 1 colour illustratio
Proteomics of Pseudomonas aeruginosa cystic fibrosis isolates to understand host adaptation
No full textTheoretical thesis.Bibliography: pages 173-196.Chapter-1: Introduction -- Chapter-2: Proteomics of host and pathogens in cystic fibrosis -- Chapter-3: Genetically and phenotypically distinct Pseudomonas aeruginosa cystic fibrosis isolates share a core proteomic signature -- Chapter-4: Quantitative proteomics by SWATH-MS reflects alterations in the phenotypic profiles of Pseudomonas aeruginosa strains isolated from cystic fibrosis patients -- Chapter-5: Pseudomonas aeruginosa cell membrane protein expression from phenotypically diverse cystic fibrosis isolates demonstrate host specific adaptations -- Chapter-6: TMT and SWATH proteomic analyses reveal adaptation dynamics of Pseudomonas aeruginosa to the hypoxic environment -- Chapter-7: General discussions -- Chapter-8: References -- Chapter-9: Appendix.Pseudomonas aeruginosa is an opportunistic bacterial pathogen commonly associated with cystic fibrosis (CF) lung infection. Numerous studies have investigated the mechanism of adaptation of P. aeruginosa to CF lungs, predominantly using the laboratory reference strain PAO1 as a model organism. However, considering the vast diversity of P. aeruginosa strains isolated from CF patients, additional information is needed to understand the role of specific proteins in this pathophysiology. This thesis describes proteomic-oriented investigations of novel CF isolated P. aeruginosa strains (PASS1-4) to better understand how this organism adapts to the harsh microenvironment, typical of the CF lung.Mode of access: World wide web1 online resource (xv, 228 pages) illustration
Multiple perspectives on self-regulation in alcohol use disorder: executive functioning, neuroimaging and psychophysiology
No full textEmpirical thesis.Bibliography: pages 213-260.Chapter One. General introduction -- Chapter Two. Executive functioning and dysregulated drinking history are associated with regulation of alcohol cue responses in non-treatment-seeking drinkers -- Chapter Three. Regulation of alcohol cue-elicited responses in alcoholic liver disease and alcohol dependent drinkers during a cue reactivity task -- Chapter Four. Impaired decision-making and reduced somatic responses indicating expectation of risky choices during the Iowa Gambling Task in severe alcohol use disorderD -- Chapter Five. Neural correlates of alcohol cue-induced brain activation and neuropsychological executive functioning measures in individuals with alcohol dependence -- Chapter Six. General discussion -- References -- Appendices.Reduced ability to regulate deleterious behaviours can lead to negative social, health, and financial outcomes. Individuals with alcohol use disorder that continue to drink despite adverse consequences from their drinking demonstrate dysregulated drinking behaviour, potentially due to difficulty in appropriate self-regulation. Identifying the factors that may be integral in appropriate regulation of responses to alcohol cues may help us better understand the underlying mechanisms involved in self-regulation in these dysregulated individuals. Elucidating the factors involved in the regulation of impulsive, motivational drives inherent in alcohol use disorder is important to inform and augment current frameworks, which do not yet adequately explain dysregulated behaviour within this complex and multifaceted disorder.Thus, the aim of thesis was to empirically examine the regulation of responses to alcohol cues and influencing factors in alcohol use disorder. A diverse methodology of neuropsychological, psychophysiological and neuroimaging techniques was applied to comprehensively evaluate regulation across various time periods surrounding cue presentation, to assess the influence of components, such as executive functioning, in appropriate regulation, and to identify overlapping evidence of underlying regulatory processes and influencing factors in a range of dysregulated alcohol use disorder samples.Four separate studies were conducted. The first applied an influential theoretical framework of executive functioning to demonstrate discrete executive functioning domains were uniquely associated with the regulation of alcohol cue-elicited responses as indicated by physiological indices in non-treatment-seeking drinkers. The second further investigated these associations using the same methodology in more severely dysregulated alcohol use disorder samples—individuals with alcoholic liver disease and alcohol dependence—and showed overall difficulties in regulation of responses in these samples that were not related to executive functioning ability. The third used the same dysregulated samples to examine whether reduced capacity for incorporating previous negative feedback leads to impaired decision-making processes regarding drinking, and found reduced physiological responses to risky choices with negative outcomes and decision-making deficits in these samples. The final study used functional neuroimaging techniques to find converging reduced neural activation in prefrontal regions related to regulation of alcohol cue responses, and worse executive functioning and dysregulated drinking measures in an alcohol dependent sample.Taken together, this thesis advances our understanding of the integral components that may underlie the progression and maintenance of alcohol use disorder. This body of work contributes to the literature involved in elucidating the role of self-regulation and influencing factors in alcohol use disorder, through a convergence of neurocircuitry and underlying neurocognitive mechanisms that is essential to advance our understanding of key processes of regulation in alcohol use disorder and better inform treatment approaches.Mode of access: World wide web1 online resource (ix, 276 pages) graphs, table