Diabetic cardiomyopathy is one of the causes of mortality and morbidity associated with diabetes. Diabetes is a disorder characterised by chronic hyperglycaemia and cardiovascular complications. The relationship between these integrally linked conditions has long been recognised, and for a significant portion of individuals the two conditions co-exist as part of metabolic syndrome. The presence of diabetes increases the risk of heart failure up to fivefold and three-fold in women and men, respectively, when compared to individuals without diabetes. While there has been a significant declining trend in cardiovascular mortality and morbidity in the general population over the past two decades, unfortunately such trends have not been seen among diabetic patients. As a result, this has persuaded many health professionals to re-evaluate their current treatment and pharmacological regimens. It is a well established fact that oxidative stress is a contributory mechanism in many agerelated disorders including T2DM, especially in those with poor glycaemic control. Thus far, clinical trials with antioxidant or carbonyl-trapping agents have produced mixed results, suggesting that the mechanisms underlying this disorder may be more complex than previously thought. Although altered systemic regulation of trace metals in diabetes has been previously investigated, it is still unclear whether changed trace metal metabolism would cause heart disease in common forms of diabetes and whether metal chelation can reverse this condition. Our hypothesis is that the accumulation of redox-active trace metals including Cu and Fe in cardiac muscle may, at least in part, result in cardiomyopathy through the generation of excess reactive oxygen species. We believed that the administration of a specific metal chelator should ameliorate this process by increasing the excretion of free systemic Cu and Fe, consequently limiting the production of superoxide oxygen free radicals and arresting the process of diabetic cardiomyopathy. Data from pre-clinical studies conducted in our laboratory using diabetic animal model with diabetes-induced abnormal Cu metabolism have been remarkably consistent in demonstrating that oral dosing with triethylenetetramine (TETA) can effectively remove systemic Cu via increased urinary Cu excretion, improve cardiomyocyte structure, reverse elevations in left ventricular collagen and β1-integrin, and alleviate heart failure, all in the presence of a consistently high circulating blood glucose profile. Taken together, these findings support the beneficial role of TETA in diabetic animal model and lay the foundation for its potential therapeutic effect in humans with diabetes. This thesis describes a series of randomised, placebo-controlled clinical trials that have investigated the metabolism of Cu and Fe and seven other trace metals in patients with chronic T2DM compared with non-diabetic control subjects. This thesis also examines the mechanism of action of TETA and addresses the hypothesis that a decrease in body systemic Cu pool through chelation therapy may improve cardiac complication in diabetic subjects. Trial 1 is a randomised, double-blind, placebo- and diet-controlled study which measured the 6d balance of Cu and Fe and seven other essential trace metals, in twenty male T2DM and twenty age-matched control subjects in whom we later probed systemic metal balance with oral TETA. Basal urinary output and balance of Cu and Fe was significantly elevated in diabetes, and the two output values correlated strongly (p<0.05). 6d treatment with 2400mg/d dose of TETA (maximum Wilson’s disease dose) has increased the urinary excretion of Cu, which was predicted by basal urinary Cu excretion, thereby causing a positive Cu balance to become negative in diabetes. Regulation of Cu metabolism was shown to be abnormal in diabetes and was selectively modified by TETA, which did not concomitantly modify Fe metabolism. Moreover, TETA did not cause a negative balance in any of the other seven trace metals monitored. These findings are consistent with TETA reversing the accumulation of free systemic Cu in diabetes, which may help to explain its potential therapeutic effects in some diabetic complications. Trial 2 investigated the acute response effect of a single 2400mg dose of TETA on urinary and serum trace metals in the first 10hr and 10~24hr post-dose. The results showed that TETA markedly increased the urinary Cu and Zn excretion in diabetes for the duration of 10hrs with the maximum excretion phase between 4~6hr post-drug (p<0.05). TETA did not change the metabolism of Mg and six other essential trace metals monitored. Trial 3 examined the dose-response effect of TETA, at and below the dose given to patients with the Wilson’s disease over a 7d period, on Cu and eight other trace metals in a subgroup of seven T2DM and seven control subjects who had completed trial 1. The results of this i i trial showed that there was a linear dose-response relationship over the dose range 300~2400 mg/d on urinary Cu excretion in both T2DM and control subjects. However, there was no significant difference between the two subject groups at any of the four doses tested. In addition, 300mg/d of TETA was effective in mobilizing Cu in both T2DM and healthy control subjects. Trial 4 described the full work-up of a sensitive LC-MS methodology to identify and quantify TETA and its metabolite(s) in human urine. Using the LC-MS, TETA metabolism and excretion was investigated by analysing the urine of seven T2DM and seven control subjects who received escalating doses of TETA (samples obtained from trial 3). I have successfully identified and characterised two major metabolites of TETA in the urine of both T2DM and control subjects, N1-monoacetytriethylenetetramine (MAT) and diacetytriethylenetetramine (DAT), the latter which has not been previously reported. The results from urinary TETA excretion analyses also showed that T2DM may metabolise TETA more extensively than control subjects, which in turn is associated with its higher uptake or bioavailability. Urinary Zn excretion was mainly linked with urinary TETA and MAT in T2DM and healthy controls, respectively, whereas urinary Cu excretion was associated with urinary TETA excretion in healthy controls and urinary TETA+MAT excretion in T2DM subjects. These results suggest that MAT may also be involved in the mechanism by which TETA extracts systemic free Cu in diabetes. The identification of the two major metabolites of TETA and the development of a robust analytical LC-MS methodology reported in this study is an important step to further investigate the pharmacological actions of TETA in diabetic individuals. Collectively, the results presented in this thesis and in association with previous animal and clinical studies from our laboratory have provided consistent supporting evidences for the use of TETA clinically as a safe and effective therapy to prevent the genesis of some diabetic complications, in conjunction with conventional complication modifying therapies.

Diabetic cardiomyopathy is one of the causes of mortality and morbidity associated with diabetes. Diabetes is a disorder characterised by chronic hyperglycaemia and cardiovascular complications. The relationship between these integrally linked conditions has long been recognised, and for a significant portion of individuals the two conditions co-exist as part of metabolic syndrome. The presence of diabetes increases the risk of heart failure up to fivefold and three-fold in women and men, respectively, when compared to individuals without diabetes. While there has been a significant declining trend in cardiovascular mortality and morbidity in the general population over the past two decades, unfortunately such trends have not been seen among diabetic patients. As a result, this has persuaded many health professionals to re-evaluate their current treatment and pharmacological regimens. It is a well established fact that oxidative stress is a contributory mechanism in many agerelated disorders including T2DM, especially in those with poor glycaemic control. Thus far, clinical trials with antioxidant or carbonyl-trapping agents have produced mixed results, suggesting that the mechanisms underlying this disorder may be more complex than previously thought. Although altered systemic regulation of trace metals in diabetes has been previously investigated, it is still unclear whether changed trace metal metabolism would cause heart disease in common forms of diabetes and whether metal chelation can reverse this condition. Our hypothesis is that the accumulation of redox-active trace metals including Cu and Fe in cardiac muscle may, at least in part, result in cardiomyopathy through the generation of excess reactive oxygen species. We believed that the administration of a specific metal chelator should ameliorate this process by increasing the excretion of free systemic Cu and Fe, consequently limiting the production of superoxide oxygen free radicals and arresting the process of diabetic cardiomyopathy. Data from pre-clinical studies conducted in our laboratory using diabetic animal model with diabetes-induced abnormal Cu metabolism have been remarkably consistent in demonstrating that oral dosing with triethylenetetramine (TETA) can effectively remove systemic Cu via increased urinary Cu excretion, improve cardiomyocyte structure, reverse elevations in left ventricular collagen and β1-integrin, and alleviate heart failure, all in the presence of a consistently high circulating blood glucose profile. Taken together, these findings support the beneficial role of TETA in diabetic animal model and lay the foundation for its potential therapeutic effect in humans with diabetes. This thesis describes a series of randomised, placebo-controlled clinical trials that have investigated the metabolism of Cu and Fe and seven other trace metals in patients with chronic T2DM compared with non-diabetic control subjects. This thesis also examines the mechanism of action of TETA and addresses the hypothesis that a decrease in body systemic Cu pool through chelation therapy may improve cardiac complication in diabetic subjects. Trial 1 is a randomised, double-blind, placebo- and diet-controlled study which measured the 6d balance of Cu and Fe and seven other essential trace metals, in twenty male T2DM and twenty age-matched control subjects in whom we later probed systemic metal balance with oral TETA. Basal urinary output and balance of Cu and Fe was significantly elevated in diabetes, and the two output values correlated strongly (p<0.05). 6d treatment with 2400mg/d dose of TETA (maximum Wilson’s disease dose) has increased the urinary excretion of Cu, which was predicted by basal urinary Cu excretion, thereby causing a positive Cu balance to become negative in diabetes. Regulation of Cu metabolism was shown to be abnormal in diabetes and was selectively modified by TETA, which did not concomitantly modify Fe metabolism. Moreover, TETA did not cause a negative balance in any of the other seven trace metals monitored. These findings are consistent with TETA reversing the accumulation of free systemic Cu in diabetes, which may help to explain its potential therapeutic effects in some diabetic complications. Trial 2 investigated the acute response effect of a single 2400mg dose of TETA on urinary and serum trace metals in the first 10hr and 10~24hr post-dose. The results showed that TETA markedly increased the urinary Cu and Zn excretion in diabetes for the duration of 10hrs with the maximum excretion phase between 4~6hr post-drug (p<0.05). TETA did not change the metabolism of Mg and six other essential trace metals monitored. Trial 3 examined the dose-response effect of TETA, at and below the dose given to patients with the Wilson’s disease over a 7d period, on Cu and eight other trace metals in a subgroup of seven T2DM and seven control subjects who had completed trial 1. The results of this i i trial showed that there was a linear dose-response relationship over the dose range 300~2400 mg/d on urinary Cu excretion in both T2DM and control subjects. However, there was no significant difference between the two subject groups at any of the four doses tested. In addition, 300mg/d of TETA was effective in mobilizing Cu in both T2DM and healthy control subjects. Trial 4 described the full work-up of a sensitive LC-MS methodology to identify and quantify TETA and its metabolite(s) in human urine. Using the LC-MS, TETA metabolism and excretion was investigated by analysing the urine of seven T2DM and seven control subjects who received escalating doses of TETA (samples obtained from trial 3). I have successfully identified and characterised two major metabolites of TETA in the urine of both T2DM and control subjects, N1-monoacetytriethylenetetramine (MAT) and diacetytriethylenetetramine (DAT), the latter which has not been previously reported. The results from urinary TETA excretion analyses also showed that T2DM may metabolise TETA more extensively than control subjects, which in turn is associated with its higher uptake or bioavailability. Urinary Zn excretion was mainly linked with urinary TETA and MAT in T2DM and healthy controls, respectively, whereas urinary Cu excretion was associated with urinary TETA excretion in healthy controls and urinary TETA+MAT excretion in T2DM subjects. These results suggest that MAT may also be involved in the mechanism by which TETA extracts systemic free Cu in diabetes. The identification of the two major metabolites of TETA and the development of a robust analytical LC-MS methodology reported in this study is an important step to further investigate the pharmacological actions of TETA in diabetic individuals. Collectively, the results presented in this thesis and in association with previous animal and clinical studies from our laboratory have provided consistent supporting evidences for the use of TETA clinically as a safe and effective therapy to prevent the genesis of some diabetic complications, in conjunction with conventional complication modifying therapies.

This study was undertaken to locate and characterise the neurons in the central nervous system that project to the kidney. In particular, the aim was to illustrate and characterise the neural link between regions in the hypothalamus known to influence renal function and fluid balance, and nerves known to innervate the kidney.

Diabetic cardiomyopathy is one of the causes of mortality and morbidity associated with diabetes. Diabetes is a disorder characterised by chronic hyperglycaemia and cardiovascular complications. The relationship between these integrally linked conditions has long been recognised, and for a significant portion of individuals the two conditions co-exist as part of metabolic syndrome. The presence of diabetes increases the risk of heart failure up to fivefold and three-fold in women and men, respectively, when compared to individuals without diabetes. While there has been a significant declining trend in cardiovascular mortality and morbidity in the general population over the past two decades, unfortunately such trends have not been seen among diabetic patients. As a result, this has persuaded many health professionals to re-evaluate their current treatment and pharmacological regimens. It is a well established fact that oxidative stress is a contributory mechanism in many agerelated disorders including T2DM, especially in those with poor glycaemic control. Thus far, clinical trials with antioxidant or carbonyl-trapping agents have produced mixed results, suggesting that the mechanisms underlying this disorder may be more complex than previously thought. Although altered systemic regulation of trace metals in diabetes has been previously investigated, it is still unclear whether changed trace metal metabolism would cause heart disease in common forms of diabetes and whether metal chelation can reverse this condition. Our hypothesis is that the accumulation of redox-active trace metals including Cu and Fe in cardiac muscle may, at least in part, result in cardiomyopathy through the generation of excess reactive oxygen species. We believed that the administration of a specific metal chelator should ameliorate this process by increasing the excretion of free systemic Cu and Fe, consequently limiting the production of superoxide oxygen free radicals and arresting the process of diabetic cardiomyopathy. Data from pre-clinical studies conducted in our laboratory using diabetic animal model with diabetes-induced abnormal Cu metabolism have been remarkably consistent in demonstrating that oral dosing with triethylenetetramine (TETA) can effectively remove systemic Cu via increased urinary Cu excretion, improve cardiomyocyte structure, reverse elevations in left ventricular collagen and β1-integrin, and alleviate heart failure, all in the presence of a consistently high circulating blood glucose profile. Taken together, these findings support the beneficial role of TETA in diabetic animal model and lay the foundation for its potential therapeutic effect in humans with diabetes. This thesis describes a series of randomised, placebo-controlled clinical trials that have investigated the metabolism of Cu and Fe and seven other trace metals in patients with chronic T2DM compared with non-diabetic control subjects. This thesis also examines the mechanism of action of TETA and addresses the hypothesis that a decrease in body systemic Cu pool through chelation therapy may improve cardiac complication in diabetic subjects. Trial 1 is a randomised, double-blind, placebo- and diet-controlled study which measured the 6d balance of Cu and Fe and seven other essential trace metals, in twenty male T2DM and twenty age-matched control subjects in whom we later probed systemic metal balance with oral TETA. Basal urinary output and balance of Cu and Fe was significantly elevated in diabetes, and the two output values correlated strongly (p<0.05). 6d treatment with 2400mg/d dose of TETA (maximum Wilson’s disease dose) has increased the urinary excretion of Cu, which was predicted by basal urinary Cu excretion, thereby causing a positive Cu balance to become negative in diabetes. Regulation of Cu metabolism was shown to be abnormal in diabetes and was selectively modified by TETA, which did not concomitantly modify Fe metabolism. Moreover, TETA did not cause a negative balance in any of the other seven trace metals monitored. These findings are consistent with TETA reversing the accumulation of free systemic Cu in diabetes, which may help to explain its potential therapeutic effects in some diabetic complications. Trial 2 investigated the acute response effect of a single 2400mg dose of TETA on urinary and serum trace metals in the first 10hr and 10~24hr post-dose. The results showed that TETA markedly increased the urinary Cu and Zn excretion in diabetes for the duration of 10hrs with the maximum excretion phase between 4~6hr post-drug (p<0.05). TETA did not change the metabolism of Mg and six other essential trace metals monitored. Trial 3 examined the dose-response effect of TETA, at and below the dose given to patients with the Wilson’s disease over a 7d period, on Cu and eight other trace metals in a subgroup of seven T2DM and seven control subjects who had completed trial 1. The results of this i i trial showed that there was a linear dose-response relationship over the dose range 300~2400 mg/d on urinary Cu excretion in both T2DM and control subjects. However, there was no significant difference between the two subject groups at any of the four doses tested. In addition, 300mg/d of TETA was effective in mobilizing Cu in both T2DM and healthy control subjects. Trial 4 described the full work-up of a sensitive LC-MS methodology to identify and quantify TETA and its metabolite(s) in human urine. Using the LC-MS, TETA metabolism and excretion was investigated by analysing the urine of seven T2DM and seven control subjects who received escalating doses of TETA (samples obtained from trial 3). I have successfully identified and characterised two major metabolites of TETA in the urine of both T2DM and control subjects, N1-monoacetytriethylenetetramine (MAT) and diacetytriethylenetetramine (DAT), the latter which has not been previously reported. The results from urinary TETA excretion analyses also showed that T2DM may metabolise TETA more extensively than control subjects, which in turn is associated with its higher uptake or bioavailability. Urinary Zn excretion was mainly linked with urinary TETA and MAT in T2DM and healthy controls, respectively, whereas urinary Cu excretion was associated with urinary TETA excretion in healthy controls and urinary TETA+MAT excretion in T2DM subjects. These results suggest that MAT may also be involved in the mechanism by which TETA extracts systemic free Cu in diabetes. The identification of the two major metabolites of TETA and the development of a robust analytical LC-MS methodology reported in this study is an important step to further investigate the pharmacological actions of TETA in diabetic individuals. Collectively, the results presented in this thesis and in association with previous animal and clinical studies from our laboratory have provided consistent supporting evidences for the use of TETA clinically as a safe and effective therapy to prevent the genesis of some diabetic complications, in conjunction with conventional complication modifying therapies.

The multivariate distribution of genetic variance is key to understanding two fundamental and interrelated processes in evolution; the ability of populations to respond to selection, and the balance of forces that maintain the genetic variance that such a response is based upon. In this thesis, I develop an analytical framework for characterizing the multivariate distribution of genetic variance and how it evolves. I then apply this framework to explore the evolution of genetic variance in multiple sexually-selected traits under artificial selection using the Drosophila serrata experimental system. An analytical framework for characterizing the multivariate distribution of genetic variance and how it evolves: First, I present a method from the statistical literature to establish the statistical dimensionality of genetic variance in a suite of traits. I evaluate the ability of this and two other methods to predict the correct number and orientation of dimensions of genetic variance by conducting a simulation study for a suite of eight traits. Second, I present a method from the materials science literature that uses multi-linear algebra to characterize the variation among matrices. I show how variation in the multivariate distribution of genetic variance among populations can be analyzed by constructing a fourth-order genetic variance-covariance tensor, and how the spectral decomposition of this tensor reveals independent aspects of change in genetic variance. I use the tensor to explore the variation in the genetic variance of eight traits among nine populations of D. serrata, and show how this variation can be associated with variation in selection pressures to determine whether selection may have affected genetic variance within populations. The evolution of genetic variance in sexually-selected traits under artificial selection: Female D. serrata display a strong preference for a particular combination of male cuticular hydrocarbons (CHCs). Individually, these pheromones display substantial genetic variance, but the genetic variance is not distributed equally among all phenotypic dimensions. In the specific CHC combination preferred by females, genetic variance is low. This is compatible with the expectation that selection will deplete genetic variance, but is contrary to the typical observation of high levels of genetic variance in individual sexually-selected traits. By artificially selecting on the trait combination preferred by females, I show that male mating success can successfully respond to selection, but the evolution of the combination of CHCs preferred by females is constrained. I then show that a key prediction of mutation-selection balance (MSB) models that has rarely been observed holds for these traits. Under MSB, genetic variance is expected to be maintained by rare alleles with large effects. Therefore, when a trait that is usually under stabilizing selection is subjected to directional artificial selection, the genetic variance is predicted to increase. I show that genetic variance increases in the CHC combination preferred by females under artificial selection, but not when another combination of the same traits with greater genetic variance is artificially selected. Complex segregation analysis indicated that the observed increase in genetic variance was a consequence of at least one allele of major effect increasing in frequency. This experiment demonstrates the importance of the past history of selection on the nature of genetic variance. General conclusion: Mutation-selection balance (MSB) is appealing as an explanation for the maintenance of genetic variance because it is simple and intuitive: the total mutation rate must be sufficiently high to replenish the variation eliminated by selection. However, MSB models seem unable to adequately explain the coexistence of the observed levels of genetic variance and strength of selection on individual traits. I contend that the failure of MSB models to explain these data is not a failure of MSB theory itself; rather it is the data that has been used to evaluate MSB models that may not be appropriate. It is now clear that there are fewer genetically independent traits than measured phenotypes, and that selection gradients measured for individual traits do not adequately reflect the nature of selection on combinations of traits. In other words, it is not possible to understand the relationship between genetic variance and selection by simply associating median levels of genetic variance and selection collated across studies as levels of genetic variance are likely to be much lower in trait combinations associated with stronger selection. Together, these observations suggest that we should be looking at the distribution of genetic variance in suites of traits and pattern of correlated selection on those same traits if we are to understand MSB.

Contemporary interest in and demand for a healthy balance between work and family/life (WF/L) commitments has resulted in the proliferation of organisations commonly referred to as family-friendly workplaces (FFWs). Such a proliferation has been met with assertions that WF/L balance is as much organisational rhetoric as it is organisational reality. Such claims are damaging for organisations that are genuinely committed to providing WF/L-friendly work environments. Additionally, such allegations if true also indicate a more serious problem of organisational ineffectiveness. This study therefore perceives a way by which FFWs can test and evaluate the effectiveness of their efforts to provide employees with WF/L balance. Three research questions drive this study: Why are FFWs’ efforts to provide WF/L balance regarded as rhetoric? What is the gap level between WF/L balance rhetoric and reality in an organisation? What organisational issues and challenges contribute to the rhetoric claim? In the absence of models or frameworks that can effectively test and measure rhetoric-reality gaps this research may be considered as ‘experimental’, since it introduces a new conceptual framework, ‘The rhetoric-reality discrepancy framework’. The framework illustrates how gaps arise and highlights key underlying contributing factors. These factors represent organisational challenges that impede WF/L balance for employees, and indicate areas that organisations need to address if they wish to dispel claims that WF/L balance is more rhetoric than reality. The ‘experimental’ nature of this framework meant that a within-case approach was the obvious choice, as it allows for the thorough study of the research problem within one organisational setting. The study was based on a case analysis of an Australian organisation that promotes itself as and has achieved formal recognition as a FFW, through nominating itself for and subsequently winning national-level work and family awards. The dual-centred nature of the research inquiry meant that a mixed paradigmatic approach was selected. A positivist approach was used to measure gap levels while an interpretivist approach was used to guide understanding of underlying contributors of these gaps. Additionally, the combined paradigm meant that the choice of research methodology was framed by a mixed methods approach. Quantitative tools such as a questionnaire survey and qualitative channels such as document analysis, personal interviews and participant observation were used. In line with Creswell’s Sequential Exploratory Design (11.2a), fieldwork commenced with the quantitative phase and on its completion was followed by the qualitative phase. SPSS software was the predominant tool used in the quantitative analytical phase while NVivo software was used in the qualitative phase. Three areas of employee experiences - their awareness of, need for, and take up of WF/L balance initiatives - were used to explore the magnitude of the rhetoric-reality gap, while the qualitative phase sought to understand what caused the gaps, what employees thought of their organisation’s efforts, and uncover emergent themes. The two methods were ‘mixed’ in the final stage of the study, and provided a rich and deeper understanding of the research problem. The quantitative results showed that employees had less than satisfactory experiences in all three areas and further supported the notion that WF/L balance may be more rhetoric than reality. The qualitative findings identified a number of contributing factors, many of which could be broadly categorised under key themes in existing literature, such as poor communication, organisational culture, differential access, cost considerations, and managerial discretion. The study also uncovered other issues that could contribute to organisational rhetoric, such as implementation challenges. One such challenge involved an organisational need to cater for a diverse workforce and therefore to provide a broad range of initiatives. Another finding is that need for particular provisions is closely linked to employees’ life stage. Both these issues mean that while organisations should offer a wide range of provisions there is also the strong likelihood that a good number of provisions may have very poor take up or have no take up. An emergent theme, though linked to few participants only, was the set of WF/L balance challenges faced by first generation Australians or immigrant workers. Another finding which appears to contradict the gap level finding of organisational rhetoric is that a number of employees either specifically identified their organisation as being WF/L-friendly or identified that flexibility was a key ingredient of WF/L balance and acknowledged that their organisation provided such flexibility. / Doctor of Philosophy (PhD)

Vertigo is the presenting symptom of some peripheral vestibular disorders, like Benign Positional Vertigo (BPV), Ménière's disease, and vestibular neuritis, and for many other clinical conditions as well. Some clinicians from the Christchurch Public Hospital suspect that there is a significant need to improve the diagnostic accuracy and overall management of patients presenting with complaints of "acute vertigo or dizziness", especially BPV and Ménière's disease. The final diagnosis of many such patients treated for these conditions in the past has been suspected to be somewhat incomplete or inappropriate. These patients were commonly referred to various other departments, where they underwent a number of investigations, particularly medical imaging [head CT (Computed Tomography) / MRI (Magnetic Resonance Imaging) scans, which were in many cases not necessary. Such delays in the process led to an extra or unnecessary burden on the limited health funds available to the hospital or to the patient. Another drawback was an elevated patient stress and anxiety as critical time was lost with the increased number of admissions, or in transferring the patient between various departments without any conclusive diagnosis and treatment. It was proposed to conduct a retrospective study on the accuracy of diagnosis of those patients admitted to Christchurch Public Hospital with complaints of acute vertigo, particularly for suspected peripheral vestibular disorders (mainly BPV and Ménière's disease) over the period of 2004-2005. Implementation of a more specific and detailed management approach at the level of the initial clinical examination or diagnostic investigations (specifically, by an early Otolaryngology/Audiology intervention) was planned for the year 2006. The two groups of patients (2004-2005 and 2006) were compared to verify the final achievements concerning the diagnostic accuracy and at various other levels with the newly implemented changes in 2006.

The aim of this research was to demonstrate the relationship between variations in summertime surface mass balance of the McMurdo Ice Shelf and atmospheric processes. The approach encompassed a broad range of techniques. An existing energy balance mass balance model was adapted to deal with debris-covered ice surfaces and modified to produce distributed output. Point based surface energy and mass balance for two key surfaces of the ice shelf were linked to different synoptic types that were identified using a manual synoptic classification. The distributed model was initialised with distributed parameters derived from satellite remote sensing and forced with data from a regional climate model. Patterns of summertime surface mass balance produced by the distributed model were assessed against stake measurements and with respect to atmospheric processes. During the summers of 2003-2004 and 2004-2005 an automatic weather station (AWS) was operated on bare and debris-covered ice surfaces of the McMurdo Ice shelf, Antarctica. Surface mass balance was calculated using the energy balance model driven by the data from the AWS and additional data from permanent climate stations. Net mass balance for the measurement period was reproduced reasonably well when validated against directly measured turbulent fluxes, stake measurements, and continuously measured surface height at the AWS. For the bare ice surface net radiation provided the major energy input for ablation, whereas sensible heat flux was a second heat source. Ablation was by both melt (70%) and sublimation (30%). At the debris-covered ice site investigated, it is inferred that the debris cover is sufficient to insulate the underlying ice from ablation. Synoptic weather situations were analysed based on AVHRR composite images and surface pressure charts. Three distinct synoptic situations were found to occur during the summers, these were defined as Type A, low pressure system residing in the Ross Sea Embayment; Type B, anticyclonic conditions across region; and Type C, a trough of low pressure extending into the Ross Sea Embayment. A dependence of surface energy fluxes and mass balance on synoptic situation was identified for the bare ice surface. The distributed model was found to produce spatial patterns of mass balance which compared well with stake measurements. Mass balance patterns show that the McMurdo Ice Shelf was generally ablating in the west, and accumulating in the east during summer. Areas of enhanced ablation were found which were likely to be caused by the surface conditions and topographic effects on the wind field. The mean summertime surface mass balance across the entire ice shelf for the 2003-2004 and 2004-2005 summers were –2.5 mm w.e. and –6.7 mm w.e. respectively. The differences between the two summers are inferred to be a result of more frequent type A conditions occurring during the summer of 2004-2005.

Diabetic cardiomyopathy is one of the causes of mortality and morbidity associated with diabetes. Diabetes is a disorder characterised by chronic hyperglycaemia and cardiovascular complications. The relationship between these integrally linked conditions has long been recognised, and for a significant portion of individuals the two conditions co-exist as part of metabolic syndrome. The presence of diabetes increases the risk of heart failure up to fivefold and three-fold in women and men, respectively, when compared to individuals without diabetes. While there has been a significant declining trend in cardiovascular mortality and morbidity in the general population over the past two decades, unfortunately such trends have not been seen among diabetic patients. As a result, this has persuaded many health professionals to re-evaluate their current treatment and pharmacological regimens. It is a well established fact that oxidative stress is a contributory mechanism in many agerelated disorders including T2DM, especially in those with poor glycaemic control. Thus far, clinical trials with antioxidant or carbonyl-trapping agents have produced mixed results, suggesting that the mechanisms underlying this disorder may be more complex than previously thought. Although altered systemic regulation of trace metals in diabetes has been previously investigated, it is still unclear whether changed trace metal metabolism would cause heart disease in common forms of diabetes and whether metal chelation can reverse this condition. Our hypothesis is that the accumulation of redox-active trace metals including Cu and Fe in cardiac muscle may, at least in part, result in cardiomyopathy through the generation of excess reactive oxygen species. We believed that the administration of a specific metal chelator should ameliorate this process by increasing the excretion of free systemic Cu and Fe, consequently limiting the production of superoxide oxygen free radicals and arresting the process of diabetic cardiomyopathy. Data from pre-clinical studies conducted in our laboratory using diabetic animal model with diabetes-induced abnormal Cu metabolism have been remarkably consistent in demonstrating that oral dosing with triethylenetetramine (TETA) can effectively remove systemic Cu via increased urinary Cu excretion, improve cardiomyocyte structure, reverse elevations in left ventricular collagen and β1-integrin, and alleviate heart failure, all in the presence of a consistently high circulating blood glucose profile. Taken together, these findings support the beneficial role of TETA in diabetic animal model and lay the foundation for its potential therapeutic effect in humans with diabetes. This thesis describes a series of randomised, placebo-controlled clinical trials that have investigated the metabolism of Cu and Fe and seven other trace metals in patients with chronic T2DM compared with non-diabetic control subjects. This thesis also examines the mechanism of action of TETA and addresses the hypothesis that a decrease in body systemic Cu pool through chelation therapy may improve cardiac complication in diabetic subjects. Trial 1 is a randomised, double-blind, placebo- and diet-controlled study which measured the 6d balance of Cu and Fe and seven other essential trace metals, in twenty male T2DM and twenty age-matched control subjects in whom we later probed systemic metal balance with oral TETA. Basal urinary output and balance of Cu and Fe was significantly elevated in diabetes, and the two output values correlated strongly (p<0.05). 6d treatment with 2400mg/d dose of TETA (maximum Wilson’s disease dose) has increased the urinary excretion of Cu, which was predicted by basal urinary Cu excretion, thereby causing a positive Cu balance to become negative in diabetes. Regulation of Cu metabolism was shown to be abnormal in diabetes and was selectively modified by TETA, which did not concomitantly modify Fe metabolism. Moreover, TETA did not cause a negative balance in any of the other seven trace metals monitored. These findings are consistent with TETA reversing the accumulation of free systemic Cu in diabetes, which may help to explain its potential therapeutic effects in some diabetic complications. Trial 2 investigated the acute response effect of a single 2400mg dose of TETA on urinary and serum trace metals in the first 10hr and 10~24hr post-dose. The results showed that TETA markedly increased the urinary Cu and Zn excretion in diabetes for the duration of 10hrs with the maximum excretion phase between 4~6hr post-drug (p<0.05). TETA did not change the metabolism of Mg and six other essential trace metals monitored. Trial 3 examined the dose-response effect of TETA, at and below the dose given to patients with the Wilson’s disease over a 7d period, on Cu and eight other trace metals in a subgroup of seven T2DM and seven control subjects who had completed trial 1. The results of this i i trial showed that there was a linear dose-response relationship over the dose range 300~2400 mg/d on urinary Cu excretion in both T2DM and control subjects. However, there was no significant difference between the two subject groups at any of the four doses tested. In addition, 300mg/d of TETA was effective in mobilizing Cu in both T2DM and healthy control subjects. Trial 4 described the full work-up of a sensitive LC-MS methodology to identify and quantify TETA and its metabolite(s) in human urine. Using the LC-MS, TETA metabolism and excretion was investigated by analysing the urine of seven T2DM and seven control subjects who received escalating doses of TETA (samples obtained from trial 3). I have successfully identified and characterised two major metabolites of TETA in the urine of both T2DM and control subjects, N1-monoacetytriethylenetetramine (MAT) and diacetytriethylenetetramine (DAT), the latter which has not been previously reported. The results from urinary TETA excretion analyses also showed that T2DM may metabolise TETA more extensively than control subjects, which in turn is associated with its higher uptake or bioavailability. Urinary Zn excretion was mainly linked with urinary TETA and MAT in T2DM and healthy controls, respectively, whereas urinary Cu excretion was associated with urinary TETA excretion in healthy controls and urinary TETA+MAT excretion in T2DM subjects. These results suggest that MAT may also be involved in the mechanism by which TETA extracts systemic free Cu in diabetes. The identification of the two major metabolites of TETA and the development of a robust analytical LC-MS methodology reported in this study is an important step to further investigate the pharmacological actions of TETA in diabetic individuals. Collectively, the results presented in this thesis and in association with previous animal and clinical studies from our laboratory have provided consistent supporting evidences for the use of TETA clinically as a safe and effective therapy to prevent the genesis of some diabetic complications, in conjunction with conventional complication modifying therapies.

Doctor of Philosophy(PhD) / In many areas of India, increasing groundwater use has led to depleted aquifers. Rainwater harvesting (RWH), the small scale collection and storage of runoff to augment groundwater stores, is seen as a solution to the deepening groundwater crisis in India. However while the social and economic gains of RWH have been highlighted, there has not yet been a thorough attempt to evaluate the impacts of RWH on larger catchment hydrological balances. The thesis here will endeavour to address this research gap through a case study of the 476 km2 ungauged semi-arid Arvari River catchment in the state of Rajasthan. Over 366 RWH structures have been built in this catchment since 1985 by the community and the local non-government organisation (NGO), Tarun Bharat Sangh (TBS). The local effects of RWH structures and general catchment characteristics were determined through field investigations during the monsoon seasons of 2007 and 2008. The analysis described large variability in both climatic patterns and recharge estimates. Potential recharge estimates from seven RWH storages, of three different sizes and in six landscape positions, were calculated using the water balance method, which were compared with recharge estimates from water level rises in twenty-nine dug wells using the water table fluctuation method. The average daily potential recharge from RWH structures is between 12 – 52 mm/day, while recharge reaching the groundwater was between 3 – 7 mm/day. The large difference between recharge estimates could be explained through soil storage, and a large lateral transmissivity in the aquifer. Approximately 7% of rainfall is recharged by RWH in the catchment, which is similar in both the comparatively wet and dry years of the field analysis. This is because the capacity of an individual structure to induce recharge is related to structure size and capacity, catchment runoff characteristics and underlying geology. Due to the large annual fluctuations in groundwater levels, the field study results suggest that RWH has a large impact on the groundwater supply, and that there is a large lateral flow of groundwater in the area. The results inferred from the field analysis were then applied to a conceptual water balance model to study catchment-scale impacts of RWH. An existing model was not used because of the paucity of data, and the need to incorporate an effective representation of RWH function and impact. The model works on a daily time step and is divided into subbasins. Within the subbasin hydrological response units (HRUs) describe the different land use/soil combinations associated with the Arvari River catchment, including irrigated agriculture. Sustainability indices, related to water from groundwater and rainfall for irrigated agriculture demand, were used to compare scenarios of management simulated in the conceptual model. The analysis shows that as RWH area increases, it reaches a limiting capacity from where developing additional RWH area does not increase the benefit to groundwater stores, but substantially reduces streamflow. This limiting capacity was also seen at the local-scale, where cumulative potential recharge from an individual RWH structure reaches a maximum daily recharge rate. These results could have important implications for RWH development, but require further research. The analysis highlighted the important link between irrigation area and RWH area. If the irrigation area is increased at the optimal level of RWH, where the sustainability indices were greatest, the resilience of the system actually decreased. Nevertheless RWH in a system increased the overall sustainability of the water demand for irrigated agriculture, compared to a system without RWH. Also RWH provided a slight buffer in the groundwater store when drought occurred. While RWH addresses the supply-side issues of groundwater operation, the institutions that form rules for groundwater use must also be considered, because of the link between irrigation area and RWH. The Arvari River Parliament, the community-based group in the case study area, was examined according to Ostrom’s factors for collective action. It was found that the major limitation for the effectiveness of this group was the minimal information available about the aquifer characteristics.