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Verification of WebAssembly programs
No full textTheoretical thesis.Bibliography: pages 51-53.1. Introduction -- 2. Literature review -- 3. Methods -- 4. Translating WebAssembly into LLVM -- 5. Validating the translation -- 6. Verifying WebAssembly -- 7. Conclusions -- References.WebAssembly is a new low-level language and compilation target mainly for the web that is already shipped in all major browsers in its minimum viable product version. The current version does not support exception handling, and therefore runtime errors cannot be handled inside the WebAssembly code. Our main contribution of this research is the development of an approach that can detect runtime errors (traps) statically using Skink, a static analysis tool. To detect the possible traps, we: 1. translate WebAssembly (stack machine) into LLVM-IR (register machine), and 2. instrument the resulting code to reduce the problem of detecting traps to a reachability problem. To test our solution, we use C/C++ benchmarks files from SV-COMP compiled into WebAssembly by Emscripten and compare the results against the standard verification process of C/C++ files by Skink. After successfully testing our approach, we apply our tool to verify programs that could abort execution due to runtime errors, detecting the conditions under which the error would occur. Internet browsers could benefit from this approach in the future, as they will execute WebAssembly modules that originate from untrusted sources and possibly with malicious intentions. Our approach would then aid in the early detection of runtime errors of these WebAssembly modules -- abstract.1 online resource (xviii, 71 pages
Structure and physiology of the ant ocelli
No full textThesis by publication.Bibliography: pages 30-33.Introduction -- Materials and methods -- Results -- Discussion -- Conclusion -- References.Most flying insects possess single lens eyes known as ocelli that assist in flight, navigation and also have an indirect role in foraging. In this thesis, I studied the ocelli of pedestrian ants by characterising the anatomy of the ocelli in three species of desert ants and physiologically measuring the visual properties of the ocelli in day- and night-active Myrmecia ants. I found that the Saharan desert ants had a fused rhabdom and anatomical features that would make them polarisation sensitive. The Australian desert ant, M. bagoti had an unusual ocellar retina with open rhabdoms wherein each retinula cell contributed microvilli in more than one orientation, making them unlikely to bepolarisation detectors. In Myrmecia, I measured the contrast sensitivity and spatial resolving power of the ocellar second order neurons. I found that in all species when both the compound eyes and ocelli were exposed to the visual stimuli, the compound eye contributed significantly to the ocellar second order neurons. However, when the compound eyes were occluded the response from the ocellar second order neurons was not quantifiable, which made it difficult to measure the visual properties of the ocelli. I discuss these anatomical and physiological findings in the ecologically relevant conditions that each species encounters.Mode of access: World wide web1 online resource (33 pages) colour illustration
ASMR : induction, personality, and consciousness
No full textTheoretical thesis.Running title: ASMR : induction, personality, and consciousness.Includes bibliographical references.Chapter 1. Introduction -- Chapter 2. ASMR : scale development and personality correlates -- Chapter 3. ASMR : sensitivity and personality correlates -- Chapter 4. ASMR : induction and frisson -- Chapter 5. ASMR : altered states and consciousness correlates -- Chapter 6. General discussion -- Appendices.Altered states of consciousness (ASC) refer to qualitative shifts in an individual's pattern of mental functioning. One such experience, autonomous sensory meridian response (ASMR), has been relatively unexplored, despite garnering significant attention online and in the media. ASMR is a pleasurable, head-orientated tingling sensation, triggered by specific audio-visual stimuli, producing feelings of relaxation, comfort and euphoria. Common triggers include whispering, soft speaking and tapping sounds. The aim of this thesis was to explore the parameters of ASMR experiences, with respect to phenomenology, prevalence, induction and relationship to personality and consciousness correlates. This was achieved through a mixed-methods approach in 4 parts. Study 1 outlined the refinement of the newly developed ASMR-15 scale, and explored the relationship of ASMR to anxiety, misophonia and absorption. Study 2 assessed the associations between Big Five personality factors and dispositional sensitivity with ASMR propensity, and the prevalence of ASMR experiences in an undergraduate student population. Study 3 outlined the successful induction of ASMR experiences in a laboratory setting, and divergence from induced frisson. Finally, Study 4 examined consciousness correlates and the possibility of ASMR existing as an anomalous experience. Taken together, the findings of these studies suggest that ASMR propensity can be measured across generalised and niche populations, and that ASMR is a relatively common, unusual experience unaccounted for by existing constructs. In addition, ASMR appears to be associated with a number of personality traits and individual differences. Lastly, the ASMR-15 appears to be a reliable and valid measure of ASMR.Mode of access: World wide web1 online resource (245 pages) table
Structural bioinformatics analysis of single nucleotide polymorphisms mapped to cannabinoid receptor 1
No full textEmpirical thesis.Bibliography: pages 37-48.1. Introduction -- 2. Methods -- 3. Results -- 4.Discussion -- 5. Conclusions -- References -- Supplementary material.G protein-coupled receptors (GPCRs) are key cell membrane-embedded receptor proteins, with critical roles in cellular signal transduction. In the era of precision medicine, understanding the role of variants on GPCR function is critical, especially from a pharmacogenomics view point. A computational method has been used to map deleterious non-synonymous single nucleotide polymorphisms (nsSNPs) to a GPCR in the endocannabinoid system, the human cannabinoid receptor 1 (CB1). Due to its central role in the endocannabinoid system, especially in the central nervous system, CB1 is an important drug target and its variability has implications for disease susceptibility and altered drug response. CB1 mutations were collated from relevant SNP databases and then computationally evaluated from neutral to deleterious. Mapping the variants on the CB1 structure showed the top twelve deleterious mutations were found to be either close to the ligand binding region or the G-protein binding site. From the top mutations, nine variants have clinical relevance, corresponding to phenotypic variations. Additionally, molecular docking analysis with a set of common ligands, variant structural analysis and, investigation of SNPs by molecular dynamics simulation, helped to understand the structural basis of `variant pathogenicity.Mode of access: World wide web1 online resource (x, 48, vii pages) diagrams, graphs, table
Physiological responses of developing Port Jackson sharks to predation and elevated temperatures
No full textTheoretical thesis.Includes bibliography.Introduction -- Chapter I: Friend or foe? Odour detection, differentiation, and anti-predator response in an embryonic elasmobranch, Heterodontus portusjacksoni -- Chapter 2: Fight, flight, or freeze? Impact of conspecific necromones on the oxygen uptake rates of a benthic elasmobranch -- Chapter 3: Developing in hot water: populations vary in the physiological cost of embryonic development in Port Jackson sharks, Heterodontus portusjacksoni -- Chapter 4: Phenotypic plasticity or local adaptation: thermal and spatial effects on the physiology and behaviour of an oviparous elasmobranch, Heterodontus portusjacksoni -- General discussions and conclusions.Elasmobranchs are especially vulnerable to perturbation given their life history characteristic including slow growth rates and relatively long gest ation time. Species which develop in eggs are thought to be at a heightened risk to predation and the most vulnerable to changes in environmental conditions, such as increased temperatures, given their lack of capacity to move and evade these situations. R elative to other taxa, elasmobranchs are relatively under studied and lack much of the baseline information regarding their embryonic development and responses to these pervasive conditions. I n this thesis, I investigate d the physiological and behavioural implications of predation and elevated temperature over embryonic and juvenile life stages of the Port Jackson shark, Heterodontus portusjacksoni. Specifically, the first two data chapters explore d the respiration strategies of embryos in response to chemi cal cues from a known predator during development, and how conspecific necromones influence these traits in juvenile sharks. Secondly, the final two data chapters investigated how rearing temperature impacts the physiology and development of embryos collec ted from two distinct populations, and the knock - on effects this may have on the behaviour and physiology after hatching. Intermittent flow - respirometry techniques were utilized to measure the physiological changes in oxygen uptake rates with exposure to d ifferent stimuli (predator cues or temperature). This methodology can be useful at determining changes in an individual's energetic need (proxy for metabolic rates), as well as determining strategies linked to changes in respiratory function. Furthermore, to determine upper thermal limits and activity patterns across temperatures, standard critical thermal methodologies and a step - wise thermal stress methodology were utilized.Predation can shape marine communities, influencing behaviour and physiology of prey. Even without the physical presence of a predator, predat or - associated cues can elicit anti - predator strategies. While most species simply show enhanced or pre - emptive escape responses to evade predatory situations, young life stages may have limited options. Specifically, during embryonic development species are restricted within their egg capsule and may be limited in their sensory capabilities. Therefore, different strategies may be utilized during these early life - history stages to allow them to ev ade predator detection. In Chapter I, I investigated the capacity of developing embryos to detect and respond to predatory odours. Embryos were exposed to predatory cues (a horn shark) and non - predator cues (a teleost fish) while in a respirometry chambers to measure changes in oxygen uptake rates. Embryos displayed variable responses both dependent on odour and on developmental stage. During development their response was strongest to non - predatory cues, in which embryos depressed oxygen uptake rates, simi lar to that of 'crypsis' responses. However, this response diminished over development which may indicate that embryos have the capacity to assess predation risk and thus regulate their response based on prior experience. At hatching, the embryo s response s w here highes 10 towards predatory cues in which they increased oxygen uptake which may be similar to that of 'fight or flight' responses in which sharks were pre - emptively trying to relocate away from predation cues.Unlike embryonic individuals, hatchling s are able to move and utilize different anti - predator strategies to that of embryos. No longer are they restrained to one place, but they can use energetically costly escape responses to evade capture. The scent of a dead conspecific (necromones) is often enough to elicit anti - predatory strategies in other species such as teleost fish and amphibians; however, it is un known if these cues would elicit any response from sharks. Given that juvenile Port Jackson sharks are found within loose aggregation in the wild, in Chapter II I explored the anti - predatory strategies of juvenile sharks and their response to conspecific necromones. Juveniles were exposed to necromones, chased (to simulate a predator attack) or both. Sharks depressed their oxygen uptake rates b y 18% in response to necromones, indicative of 'crypsis' response. Unsurprisingly, when chased, regardless of if exposed to necromones, oxygen uptake rates increased to meet the energetic demand of exercise, and any other associated processes ...1 online resource (138 pages) illustration
Organisational career management in a protean and boundaryless world: a mixed-methods study
No full textThesis by publication.Bibliography: pages 229-267.Chapter 1. General introduction -- Chapter 2. How has organisational career management changed in 20 years? -- Chapter 3. Understanding the factors that support employee engagement in OCM -- Chapter 4. Voluntary career change : a systematic review and research agenda -- Chapter 5. Importance of leadership in supporting employee career self-management -- Chapter 6. General discussions -- Complete list of references.Employee development is an integral component of strategic human resources management to engage and retain employees. Protean and boundaryless career theories suggest that that organisational responsibility for employee career development has decreased. This theoretical shift was based on the assumption that with increased organisational change, downsizing, and re-structuring, employees would no longer be in a position to rely on organisations to support their career development, and instead employees would need to take responsibility for their own employability. More than two decades after these initial assertions, a small body of empirical research has highlighted that this shift from organisation to individual responsibility has not been as dramatic as first hypothesised. Rather than diminishing, the role of organisations in career development is as important as ever. This paradox between theory and practice highlights a gap in theoretical understanding of the role of the organisation in career development. In this PhD thesis, we place organisational career management (OCM) under the research microscope. First, data on the types and frequencies of individual OCM practices reported in the 1996, 1999, 2004, 2009, and 2015 Australian Cranet surveys was examined. Counterintuitive findings indicate that the use of more than half the OCM practices increased over time. Second, we interviewed 51 employees to investigate their perception of OCM. Employees identified both formal and informal OCM, and findings highlight that rather than operating in opposition, individually-driven career development and OCM are working in partnership. Next, in an effort to understand how organisations can support employees navigating voluntary career change, a systematic and theoretical review of voluntary career change was conducted. This review highlights lack of empirical research on the utility of important and well-developed career transition models and the importance of organisational factors in buffering the negative impact on employees during the pre-career change period. Finally, further investigating two of the factors that support employee engagement in OCM, we adapted the social cognitive model of career self-management to examine the factors that enable career adaptive behaviours for employees navigating career change. Our findings demonstrate that the social cognitive model of career self-management model is a useful framework for design of strategic organisational career management systems. Our overall findings indicate OCM remains an important component of a human resources strategy.Mode of access: World wide web1 online resource (xiv, 267 pages) graphs, table
Hypothalamic control of blood pressure in polycystic kidney disease
No full textThesis by publication.Bibliography: pages 205-294.1. Introduction -- 2. Increased excitatory regulation of the hypothalamic paraventricular nucleus circulating vasopressin results in the hypertension observed in polycystic kidney disease -- 3. Angiotension II differentially regulates blood pressure and sympathetic nerve activity in polycystic kidney disease -- 4. The subfornical organ drives hypertension in polycystic kidney disease via the hypthalamic paraventricular nucleus -- 5. High water intake provides renal and cardiac autonomic benefits in a rat model of polycystic kidney disease -- 6. General discussion -- References -- Appendices.Polycystic kidney disease (PKD) is characterised by the progressive accumulation of multiple bilateral renal cysts that threaten body-fluid homeostasis and glomerular filtration. In PKD patients, the development of hypertension and baroreflex dysfunction both contribute to a high risk of cardiovascular mortality, but the underlying mechanisms are poorly understood. This thesis examined the hypothesis that altered signalling within the hypothalamus and elevations in extracellular fluid osmolality contribute to hypertension and baroreflex dysfunction in a rat model of PKD, the Lewis Polycystic Kidney (LPK) rat.The first goal of this thesis was to determine whether the ongoing activity of neurons in the hypothalamic paraventricular nucleus (PVN), a structure that regulates arterial pressure through multiple neural and humoral outputs, contributes to the maintenance of hypertension and baroreflex dysfunction in LPK rats in early and advanced stages of the disease. Acute pharmacological experiments in anaesthetised animals showed that an early increase in the glutamatergic excitation of PVN neurons maintains hypertension, but not baroreflex dysfunction, in LPK animals. This study also suggested that vasopressin release maintains a component of the hypertension in anaesthetised LPK rats but is independent of PVN neuronal activity and might therefore involve the supraoptic nucleus. However, additional work showed that while supraoptic nucleus vasopressin neurons are more active in LPK rats, chronic systemic inhibition of V1A receptors is not anti-hypertensive.Further studies examined the source of elevated PVN glutamatergic tone in LPK rats. The first hypothesis examined was that the local signalling of angiotensin II, a critical regulator of PVN glutamatergic tone, is enhanced in LPK rats. It was shown that the sensitivity but not tonicity of the angiotensin II type 1 receptor (AT1R) is enhanced in LPK rats and that its activation preferentially drives vasopressin release rather than sympathetic outflow via an indirect interaction with PVN astrocytes. Subsequent work determined whether heightened PVN glutamatergic tone is produced by a greater ongoing discharge of glutamatergic afferents in LPK rats. It was demonstrated that the subfornical organ (SFO), a sensory structure that detects plasma angiotensin II and osmolality levels, contains more activated PVN-projecting neurons in LPK animals and is the primary source of enhanced glutamatergic drive to the PVN in this disease model. However, PVN glutamatergic tone was not reduced by chronic suppression of AT1R (with pharmacology) or plasma hyperosmolality (via high-water intake). High-water intake nevertheless provided novel cardiovascular benefits in LPK rats, including an improvement in hypertension and cardiac baroreflex function.These experiments further our understanding of the origins of cardiovascular dysfunction in PKD, highlighting a SFO-PVN neuronal pathway as a novel therapeutic target to manage hypertension. The work encourages the clinical investigation into whether a prescribed increase in water consumption protects against the development of cardiovascular disease in PKD patients.Mode of access: World wide web1 online resource (xiv, 307 pages) colour illustration
A framework for the establishment of an environmental court in Indonesia: opportunities and challenges
No full textTheoretical thesis.Bibliography: pages 215-228Chapter 1: The need to strengthen environmental adjudication: an introduction -- Chapter 2: An effective environmental court and its characteristics: an analytical framework -- Chapter 3: Current structure and practices of adjudicating environmental cases in Indonesia -- Chapter 4: Competence of the judiciary in handling environmental cases in Indonesia -- Chapter 5: Using scientific evidence to handle environmental cases in the Indonesian judiciary -- Chapter 6: Framework for an environmental court in Indonesia: the way forward -- Chapter 7: Conclusion.Environmental cases are widely known to be multidimensional and scientifically sophisticated, and to involve uncertainty. Science, economics and technology are changing faster than the law, which makes it difficult for the judiciary to adjudicate complex environmental cases. Traditional processes of adjudication are insufficient for handling many environmental cases efficiently and effectively. Recently, there has been a significant move in favour of environmental courts and tribunals (ECTs) worldwide, which have unique characteristics and different level s of success and challenges. However, despite the challenges of judicial specialisation, ECTs are acknowledged to be the mechanism that can best protect environmental rights and achieve sustainable development. Given the current environmental issues, challenges and progress in adjudicating environmental cases in Indonesia, this thesis proposes the creation of a specialised environmental court for Indonesia and develops a framework for its establishment. The thesis examines select ed ECTs and their unique features, success es and challenges to deduce instructive lessons for Indonesia, and it tailors relevant international experience to suit the country's unique and special features. Thus, this study analyses (a) the relevance and applicability of foreign experience in the Indonesian context and (b) the problems and prospects of establishing an environmental court in Indonesia. The thesis identifies and draws upon the features of the most effective model of an environmental court that best suits Indonesia 's legal culture, judicial system and specific environmental goals to determine a framework for the establishment of a specialised environmental court.This thesis concludes that an environmental court would essentially be a specialised environmental court (pengadilan khusus lingkungan) within the general and administrative courts, which can offer a better forum to effectively facilitate the adjudication of complex environmental cases in Indonesia. A specialised environmental court under the general court would adjudicate civil and criminal matters, whereas a specialised environmental court under the administrative court would adjudicate administrative matters. Some preconditions must exist within and outside the Indonesian judiciary to realise the creation of a specialised environmental court. The Indonesian Government must take a step-by-step approach to establish a specialised environmental court. To this end, this thesis recommends some essential and sequential steps for policymakers to take as a foundation for developing a strategic plan for the creation of an environmental court. This plan will assist the Indonesian Government to measure its progress towards establishing a specialised environmental court. The outcome of this research will contribute to (a) the existing literature on environmental courts, (b) the modernisation and reform of the Indonesian judiciary and (c) the creation of a domino effect on other countries that are desirous of establishing ECTs amid challenges and conditions similar to those in Indonesia.1 online resource (xxiv, 229 pages
Barbarians are people too: the discourse of barbarism in young adult fantasy fiction
No full textTheoretical thesis.Bibliography: pages 188-192.Chapter 1. The discourse of barbarism -- Chapter 2. Why fantasy? -- Chapter 3. Barbaric oppression: why societies go wrong -- Chapter 4. Manly man in tight thighs: barbarism, masculinity, and young adult fantasy fiction -- Chapter 5. Barbaric subjectivity and the power of language -- Conclusion.Barbarism and the idea of the barbarian is an old and powerful concept. Initially developed by the Greeks as a method for delineating Greek and 'other', the idea was gradually appropriated into Roman literature and political rhetoric in order to both express a sense of exclusion of the barbarian and also reinforce a sense of their own cultural and intellectual superiority. In doing so, a discourse around the barbaric emerged and continued to adapt to the changing socio-cultural landscape of the Roman world ...1 online resource (192 pages
A scalable non-linear noise model for high-electron-mobility transistors
No full textTheoretical thesis.Bibliography: pages 54-57.1 Introduction -- 2 Modelling noise in FETs -- 3 Noise model based on charge fluctuations -- 4 Complete non-linear noise model -- 5 Conclusion and future work.Noise is the unwanted random fluctuations in a signal, voltage or current. Over a frequency range from a few GHz to tens of GHz, the major noise contributors in the High-Electron-Mobility Transistor (HEMT) were thought to be partially correlated thermal drain-noise and gate-noise currents. However, the thermal origin of the drain-noise current cannot be explained with sub-micrometre HEMT theory. Furthermore, the measurements also reflect that both the noise figure and the optimum signal source admittance cannot be accurately defined using the conventional two noise sources. A simple but novel scalable non-linear noise model is presented in this thesis to predict the response and number of noise current sources in the HEMT in a frequency range from a few GHz to tens of GHz. The model uses probability theory, which is one of the best ways to predict the randomness associated with any quantity, for modelling noise in HEMTs, and describes how three noise sources are essential to completely define the noise performance of the HEMT over that frequency range. A comparison between the simulated and measured noise parameters is also carried out to test the validity of the model.1 online resource (xv, 57 pages) colour illustration