Journal and Proceedings of The Royal Society of New South Wales
STUDENT THESES ABSTRACTS IN VOLS 123-132 (Part 5 of 5: VOLS 131-132)
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CONTENTS
(in chronological order of publication)
| 1984-1989 [v118 pts 1-2 to v122 pts 3-4] | |
| Go to Theses Abstracts Archive Part 1 | |
| 1990-1993 [v123 pts 1-2 to v126 pts 3-4] | |
| Go to Theses Abstracts Archive Part 2 | |
| 1990-1994 [v127 pts 1-2 to v128 pts 3-4] | |
| Go to Theses Abstracts Archive Part 3 | |
| 1990-1994 [v129 pts 1-2 to v130 pts 3-4] | |
| Go to Theses Abstracts Archive Part 4 | |
| 1998 [v131 pts 1-2] | |
| Chopin, L.K. | Some cardiovascular morphological specialisations and aspects of cardiovascular control in the lower vertebrates, Carcharhinus melanopterus, Rhinobatos typus, Neoceratodus forsteri and Arius graegei. |
| Dowling, P.J. | "A great deal of sickness". Introduced diseases among the aboriginal people of colonial South-east Australia 1788-1900 |
| Fergusson, K.J. | Integer factorisation algorithms |
| Glover, J. | Male sterile mutants of Arabidopsis. Cloning of a T-DNA tagged gene |
| Jahufer, M.Z.Z. | Developing efficient white clover (Trifolium repels L.). Breeding strategies for the dryland summer moisture stress envirtonments of Australia |
| Quinn, R. | NGOs, peasants and the state: transformation and intervention in rural Thailand, 1970s-1990s |
| 1998 [v131 pts 3-4] | |
| Baada, I.A. | Survival Analysis Diagnostics |
| Chopin, L.K. | Some Cardiovascular Morphological Specialisations and Aspects of Cardiovascular Control in the Lower Vertebrates, Carcharhinus melanopterus, Rhinobatos typus, Neoceratodus forsteri and Arius graeffei |
| Hockings, G.I. | Neuroendocrine Studies on the Function of the Normal and Abnormal Human Hypothalamic – Pituitary – Adrenal Axis |
| Lanspeary, P.V. | Establishing Very Low Speed, Disturbance-free Flow for Anemometry in Turbulent Boundary |
| Vickery, K.A. | Molecular Recognition between DNA and CHIRAL Intercalative Metalloprobes |
| 1999 [v132 pts 1-2] | |
| John R Burgess | The Pathogenesis and Behaviour of Clinical Endocrinopathy in Multiple Endocrine Neoplasia Type 1 |
| Monica Anne Hamilton-Bruce | Conventional and Topographic Electroencephalography and Somatosensory Evoked Potential Studies in Ischaemic Stroke |
| Anthony H. Harakuwe | Capillary Zone Electrophoresis: Studies on Separation Selectivity of Inorganic Anions |
| Helen Monks | The Management of Regional Economic Development Organisations with a Particular Emphasis on Funder Relationships |
| Firoozeh Rabbani | A Study Of The Scaling Behavior Of Some Cr2O3 Forming Alloys With Relevance To Inter-connect Plates For Solid Oxide Fuel Cells |
| Seán Stewart | Thermodynamic and Dielectric Properties in Modulated Two-dimensional Electronic Systems |
| Christina Wright | "Where The Spirits Meet" A History of The National Museum And Art Gallery, Waigani, Papua New Guinea |
| 1999 [v132 pts 3-4] | |
| Cooper, Ian | Geology And Geochemistry of The Wallendbeen Area, N.S.W. |
| Corbyn John Andrew | Air Movement in the Human Sleeping Environment and Sudden Infant Death |
| Low, Chun Yu Danny | Prediction of the Dimensional Accuracy of Small Extra-coronal Titanium Castings |
| Murphy-Poulton, Susam F. | A Study of Some Ternary Tetradentate Complexes As Phenanthrene-based Chiral Metallointercalators |
| Orr, Rhonda | Effect of Exercise on Diffusing Capacity in Patients with Cystic Fibrosis |
Vol 131 parts 1-2, pp. 39-40 [1998] |
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Some Cardiovascular Morphological Specialisations Aspects of Cardiovascular Control in the Lower Vertebrates, Carcharhinus Melanopterus, Rhinobatos Typus, Neoceratodus Forsteri and Arius Graeffei
Lisa K. Chopin
Abstract of Thesis submitted for the Degree of Doctor of Philosophy at The University of Queensland
(A number of errors were inadvertently printed in this edition of the abstract; a corrected version was later printed in vol.131, pts 3-4, pp. 115-116); and reproduced below.
Vol 131 parts 1-2, pp. 39-40 [1998] |
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Thesis Abstract: "A Great Deal of Sickness". Introduced Diseases among the Aboriginal People of Colonial Southeast Australia 1788-1900
Peter J. Dowling
Abstract of a Thesis Submitted for the Degree of Doctor of Philosophy, The Australian National University, Canberra
Palaeopathological studies have sought to build up a picture of Australian Aboriginal health before European settlement in 1788, and epidemiological studies of Aboriginal health in the twentieth century are now legion. But, despite a growing body of literature on Aboriginal history in the intervening colonial period, this remains an under-studied period from the viewpoint specifically of Aboriginal health. This thesis is a contribution to filling that gap through an examination of documentary and skeletal evidence on the changing biomedical situation experienced by Aboriginal populations of Southeast Australia from 1788 to 1900.
This thesis examines one of the major biological components of this change - the diseases that were introduced into Australian Aboriginal populations during the process of colonisation. The epidemiology, timing, diffusion of diseases are considered with specific attention given to infectious and respiratory diseases that were responsible for causing major epidemics of morbidity and mortality.
A medical model for the contact period in the late 18th and 19th centuries is proposed. This model considers three major stages in the disease environment of Aboriginal populations in Southeast Australia; a pre-contact stage with endemic pathogens causing chronic diseases and limited epidemics, an early contact stage where introduced exotic human diseases cause severe epidemics of infectious and respiratory diseases among Aboriginal populations, and a third stage where remaining Aboriginal populations were institutionalized on government and mission settlements and were subjected to a high level of mortality from the introduced diseases.
The major epidemic diseases during the early contact stage were smallpox, syphilis, tuberculosis, influenza, and measles. Each of these diseases was responsible for excessive morbidity and mortality. During the period of institutionalisation infectious and respiratory diseases were responsible for over 50% of recorded deaths on 8 separate Aboriginal settlements in Southeast Australia. The major diseases recorded as causes of death were tuberculosis, bronchitis, pneumonia, diarrhoea and dysentery.
Aboriginal and non-Aboriginal Australian infant mortality rates are calculated to provide an indicator to compare the state of health of the two populations. Aboriginal rates were high when compared to the non-aboriginal populations of Victoria and South Australia. The rates reveal a substantial health differential between Aboriginal and non-Aboriginal populations. Aboriginal infant mortality has improved into the latter quarter of the twentieth century but the corresponding improvement in non-Aboriginal infant mortality has been at a much higher rate. The gap between the health status of each has widened rather than narrowed over the last one hundred years.
Vol 131 parts 1-2, p. 41[1998] |
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Thesis Abstract: Integer Factorisation Algorithms
Kevin John Fergusson
A Thesis submitted for the Degree of Master of Science University of Western Australia.
This thesis concerns itself with the problem of decomposing an integer into its prime factors. The problem can be equivalently posed as the question: Given the number n, what whole numbers a and b (both larger than one) will multiply together to give n? This problem has received much research interest because its difficulty of solution is exploited in many cryptosystems, in particular, the popular RSA cryptosystem discovered by Rivest, Shamir and Adleman at MIT in 1977. A survey of integer factorisation algorithms is presented as well as some of my attempts at generalizations or variations of existing methods in the hope that this comprises a comprehensive overview of the current state of the art of integer factorisation.
The first chapter of this thesis introduces the problem of integer factorisation and provides detailed analyses of algorithms such as Pollard's rho method and Brent's method. Chapter one also provides an alternative analysis of an algorithm which is simpler than Pollard's rho method. Random walks in number fields are suggested as an alternative to the rho methods, which are basically random walks in congruence classes of the integers.
The theory of elliptic curves leads the reader into the elliptic curve method of factorisation in the third chapter, and this theory provides the basis for a running time analysis of the algorithm. The fourth chapter involves the theory of binary integer quadratic forms in developing the class group method of factorisation. Various implementations of the algorithms are presented and analysed in the hope that this might lead to some more general method. Also, auxiliary algorithms for these previously mentioned methods of factorisation are presented with some generalisation attempted. One popular example of an auxiliary method is a random walk among the group elements. The other methods deviate slightly from this example.
Chapters six and seven explore methods of integer factorisation which attack the problem from a different viewpoint, notably the continued fraction method, the quadratic sieve, the multiple polynomial quadratic sieve and the number field sieve. Attempts are made to generalise these algorithms or to provide variations of them in the hope of an improvement in running time. The thesis concludes with a summary of the theoretical running times of the algorithms.
Vol 131 parts 1-2, p. 42 [1998] |
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Thesis Abstract: Male sterile mutants of Arabidopsis. Cloning of a T-DNA tagged gene
Julie Glover
Abstract of a Thesis Submitted for the Degree of Doctor of Philosophy at The Australian National University, Canberra
Fertile pollen is the culmination of physiological, biochemical and morphological processes requiring the coordinated spatial and temporal expression of a large number of gametophytic and sporophytic genes. Although male sterile mutants have been described in many different plant species, few of the genes responsible have been cloned. This study describes the screening of 21 T-DNA generated, reduced fertility lines of Arabidopsis thaliana in order to identify a tagged male sterile mutation and clone the interrupted gene. In two lines the male sterile mutation was segregating with a T-DNA insert. Further studies focused on one of these, Line 178.
The nuclear male sterile mutation in Line 178 was found to be allelic with a previously described EMS-generated mutant, ms5. The phenotype of this new, tagged allele (ms5-2) is the result of complex interplay between genetic and environmental factors. Using both alleles the ms5 mutation was mapped to chromosome 4. Plant DNA adjacent to the T-DNA was isolated from the ms5-2 mutant plants and isolation of the equivalent wild-type sequences is described. Two open reading frames were detected in the region of T-DNA integration; one of them corresponding to a β-tubulin gene (TUB9)that has previously been sequenced. The T-DNA has integrated 601 bp downstream of the stop codon for this TUB9 gene and transcript levels appear unaffected.
A novel gene that was interrupted by the T-DNA insertion was identified and a cDNA isolated from an Arabidopsis flower bud library. Northern analysis failed to detect expression of the putative MS5 gene (pMS5) in flower buds or leaves of wild-type plants. The T-DNA has inserted into the coding region of this gene, truncating the protein by 112 amino acids. Southern analysis suggests that pMS5 may be a member of a small gene family. The predicted protein sequence for this gene has homology with two expressed sequence tags (ESTs), one from Arabidopsis and one from rice. These homologies are limited, suggesting that these are members of the pMS5 gene family rather than being functional homologues. Complementation experiments were initiated in Arabidopsis to determine whether this gene corresponds to the MS5 gene.
Vol 131 parts 1-2, pp. 43-44[1998] |
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Thesis Abstract: Developing Efficient White clover (Trifolium Repels L.). Breeding Strategies for the Dryland Summer Moisture Stress Environments of Australia
M. Z. Z. Jahufer
Abstract of a Thesis submitted for the Degree of Doctor of Philosophy at The University of Queensland
Summer moisture stress has been identified as a major constraint to vegetative persistence and herbage yield of white clover in Australia. Genetic improvement of vegetative persistence and herbage yield of white clover for dryland summer moisture stress environments is a key objective in the development of new cultivars for the Australian grazing industries.
The Ph.D. research program was focused on: (i) studying the genotypic variation for stolon and other morphological attributes, including seasonal herbage yield, present in a world sourced collection of white clover germplasm accessions maintained at the Genetic Resource Centre, Glen Innes, New South Wales (NSW); (ii) examining the effects of environmental variation for level of moisture stress during summer on the expression of variation for stolon attributes and herbage yield; (iii) estimating quantitative genetic parameters for stolon morphological attributes and herbage yield; (iv) testing the hypothesis that crossing of morphologically diverse plants may be a useful strategy for breaking the negative association between vegetative persistence and herbage yield of white clover under dryland summer moisture stress conditions of Australia.
Morphological characterisation of the total world sourced collection of white clover germplasm (439 accessions) was conducted on different batches of accessions over a period of five years under dryland summer moisture stress conditions. There was significant (P < 0.05) genotypic variation among accessions for all the morphological attributes including herbage yield. The performance of the two check cultivars, Haifa and Huia, included in each batch provided a basis for adjustment of the data for attribute-by-year interaction effects by estimation of Best Linear Unbiased Predictions (BLUPs). Pattern analysis enabled identification of germplasm accessions that could be used for the development of white clover cultivars through recurrent selection. The germplasm collection was also found to be deficient in genotypes with high stolon density, high number of branches, high number of rooted nodes and large leaves.
Genetic families produced using the North Carolina I (NCI) mating design were evaluated for herbage yield and key stolon attributes conferring vegetative persistence in dryland summer moisture stress and irrigated treatments over three years. The combined analysis of variance of the families across environments and years indicated the presence of genotypic variation for all the stolon attributes and summer herbage yield. Large genotype-by-environment-by-year-interactions were estimated. The phenotypic and genotypic correlation coefficients between the attributes, estimated for the genetic families, indicated that the undesirable negative association between vegetative perenniality and herbage yield had been changed. This provided strong evidence that the negative correlation coefficients reported from other studies are a result of linkage and not pleiotropy.
The following recommendations were made to improve the efficiency of breeding white clover for dryland moisture stress environments in Australia: (i) upgrade the germplasm collection to compensate for plant types that are deficient; (ii) generation of new genotypic recombinants by crossing morphologically diverse accessions; (iii) use of multi-site testing during all stages of evaluation in the breeding program; (iv) use of progeny tests to identify parents with good general combining ability; and (v) use of row-column experimental design methodology and pattern analysis methodology at all stages of testing as statistical tools to enhance the opportunities for identification of useful germplasm from the world collection and cultivars with improved adaptation from the breeding program.
Vol 131 parts 1-2, pp. 44-45 [1998] |
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Thesis Abstract: NGOs, Peasants and the State: Transformation and Intervention in Rural Thailand, 1970s-1990s
Rapin Quinn
Abstract of Thesis Submitted for the Degree of Doctor of Philosophy The Australian National University, 1997
This study examines people-centred Thai NGOs trying to help peasants empower themselves in order to compete better in conflicts over land, water, forest, and capital, during the 1970s to '90s. The study investigates how the NGOs contested asymmetric power relations among government officials, private entrepreneurs and ordinary people while helping raise the peoples confidence in their own power to negotiate their demands with other actors.
The thesis argues that the NGOs are able to play an interventionist role when a number of key factors coexist. First, the NGOs are able to understand loci situations which contain asymmetric power relations between different actors, in relation to current changes in the wider context of the Thai political economy and seize the time to take action. Secondly, the NGOs are able to articulate a social meaning beyond the dominating rhetoric of the 'state' and the 'capitalists' which encourages the people s, participation in collective activities. Thirdly, while dealing with one problem in social relations and negotiation with local environment, the NGOs are able to recognise new problems as they arise and rapidly identify a new political space for the actors and to renegotiate their conflicting interests and demands. Fourthly, the NGOs are able to recreate new meanings, new actors and reform their organisations and networks to deal with new situations.
Finally, the NGOs are able to effectively use three pillars of their movement, namely individuals, organisations and networks to deal with everyday politics and collective protest. The case studies in three villages in Northern Thailand reveal that the NGOs were able to play an interventionist role in specific situations through their alternate development strategies somewhat influenced by structural Marxism. The thesis recommends that the NGO interventionist role be continued so as to overcome tensions within the NGO community, for instance, between the NGOs working at the grassroots level and the NGOs working at regional and national levels (including NGO funding agencies); local everyday conflicts; and the bipolar views of a society among the NGOs expressed in dichotomous thinking between 'rural' and 'urban, 'community' and 'state', conflict and order, actor and system.
The fragmentation of NGO social and environmental movements showed that there is no single formula or easy solution to the problems. If the NGOs want to continue their interventionist role to help empower ordinary people and help them gain access to productive resources, they must move beyond their bipolar views of a society to discover the middle ground to search for new meanings, new actors, new issues and to create again and again counter-hegemony movements. This could be done by having abstract development theories assessed and enriched by concrete development practices and vice versa. Both theorists and practitioners need to use their own imagination to invent and reinvent what and how best to continue.
Vol 131 parts 3-4, p. 113 [1998] |
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Survival Analysis Diagnostics
Ingrid Baada
Abstract of a Thesis Submitted for the Degree of Doctor of Philosophy at Queensland University of Technology
The Cox proportional hazards model for assessing survival data continues to grow in popularity, especially in the medical context. This Thesis provides diagnostics to determine if observations are influential for the parameter estimates in the Cox proportional hazards model.
Diagnostics such as Cook's distance have been available for the ordinary least squares model for many years. In order to extend them so they can be used for the proportional hazards model it is necessary to first extend them to the generalised least squares model. For models with normal errors with known variance matrix, the change in parameter estimates that occurs when cases are removed from the dataset can be calculated exactly. For generalised least squares the change is exact if it can be assumed that the estimates of the pararneters in the variance matrix do not change when cases are removed.
The Newton-Raphson fitting procedure for the proportional hazards model is an iterative procedure. If we find fully iterated estimates of regression parameters then we can take one-step of a new iterative procedure toward parameter estimates for a reduced dataset, For the proportional hazards model with the usual loglinear relative risk function, the formula used for the Newton-Raphson iterative procedure looks like the formula for calculating the exact change in the generalised least squares model.
The one-step estimates of the changes in parameter estimates for the proportional hazards model can then be used to construct quantities like Cook's distance.
This thesis shows that the data augmentation method commonly used for proportional hazards is a type of case deletion method. A new case deletion method is examined.
Vol 131 parts 3-4, pp. 115-116 [1998] |
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Some Cardiovascular Morphological Specialisations and Aspects of Cardiovascular Control in the Lower Vertebrates, Carcharhinus melanopterus, Rhinobatos typus, Neoceratodus forsteri and Arius graeffei
Lisa K. Chopin
Abstract of a Thesis for the Degree of Doctor of Philosophy at the University of Queensland.
[This Abstract was initially published in vol 131 parts 1-2, but with a number of printing errors. The corrected version follows]
Catecholamines released from chromaffin cells appear to play an integral role in the regulation of the cardiovascular system of lower vertebrates. Chromaffin cells are present in the axillary and suprarena1 bodies of R. typus and C. melanopterus; in the atrium, intercostal arteries and the posterior cardinal vein of N. forsteri; and in the posterior cardinal vein in the head kidney of A. graeffei. Although chromaffin cells have been described in the sinus venosus of other elasmobranchs, there are no chromaffin cel1s here in R typus and C. melanopterus. Chromaffin tissues in C. forsteri and A. graeffei exhibit tyrosine- hydroxylase-immunoreactivity. U1trastructural studies show that chromaffin cells contain large numbers of chromaffin-positive, electron-dense, membrane-bound granular vesicles, Two cell types (presumably adrenaline- and noradrenaline-storing cells) can be distinguished on the basis of granule electrondensity in R. typus, C. melanopterus and in A. graeffei but only one cell type can be distinguished in N. forsteri. Chromaffin cells receive an innervation in these lower vertebrates, and synaptic specialisations have been observed in close association with chromaffin cells.
The role of the autonomic nervous system in the regulation of the cardiovascular system is investigated. Physiological and anatomical studies failed to reveal evidence for an autonomic innervation of the branchial vasculature of C. melanopterus. Perfused gill preparations are responsive to noradrenaline with vasoconstriction at high concentrations and vasodilatation at low concentrations. The branchial vasculature constricts via muscarinic receptors in response to acetylcholine. The distribution of the caudal autonomic nervous system of C. melanopterus and R. typus is similar to that of other elasmobranchs.
Adrenergic nerve fibres were demonstrated histochemically. Isolated tail preparations in R. typus and C. melanopterus are responsive to perfused catecholamines and acetylcholine which both vasoconstrict the tail vasculature. Nerve stimulation experiments gave inconclusive results in these preparations. The functional role of the autonoxnic nervous system in regulating the tail vasculature of elasmobranchs remains controversial. This is the first study to demonstrate catecholaminergic nerves in the dipnoans. The pulmonary artery and branchial vasculature contain catecholamine fluorescent nerves which have the ultarastructural features of catecholaminergic nerves. Adrenergic nerves, revealed immunohistochemically, are associated with the systemic secondary vessel system of the teleost, A. graeffei. Vascular casts are used to describe the systemic secondary vessel system in A graegei, and some fine structural features of this system are described for the first time in this study. No morphological features of such a system are present in R typus, C. melanopterus or N. forsteri. The measurement of a low erythrocyte content in the cutaneous veins of R. typus suggests that a functional shunting of erythrocytes could be occurring.
The four species studied share many cardiac ultrastructural features. Exposure of R. typus to a low salinity environment for three days resulted in some morphological and morphoxnetric changes in myoendocrine cell ultrastructure presumably due to sn increase in atrial natriuretic or related peptide production.
Vol 131 parts 3-4, pp. 117-118 [1998] |
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Neuroendocrine Studies on the Function of the Normal and Abnormal Human Hypothalamic-Pituitary-Adrenal Axis
Gregory I. Hockings
Abstract of a Thesis Submitted for the Degree of Doctor of Medicine at The University of Queensland
This thesis reports several studies which assessed the function of the hypothalamic-pituitary-adrenal axis (HPAA) in healthy human subjects and in patients with (1) myotonic dystrophy (DM), an autosoxnal dominantly transmitted form of muscular dystrophy which involves multiple organ systems; and (2) post-traumatic stress disorder (PTSD), a psychiatric condition which results from exposure to a very stressful, dangerous situation. Plasma concentrations of adrenocorticotropic hormone (ACTH), cortisol, and arginine vasopressin (AVP) were measured in response to ad- ministration of the opioid antagonist naloxone, exogenous AVP and synthetic ACTH. All studies were placebo-controlled and singleblinded.
In healthy volunteers, administration of both naloxone and AVP resulted in a synergistic ACTH response compared to administration of each agent alone, similar to the synergism previously reported between corticotropin-releasing hormone (CRH) and AVP. This finding indicates that, in humans, naloxone stimulates the HPAA predominantly or exclusively via increased release of hypothalamic CRH, similar to its mechanism of action in animal studies.
In DM patients, the ACTH response to naloxone was markedly increased compared to control subjects. Pre-treatment with nifedipine (which blocks dihydropyridine (DHP)-sensitive Ca2+ transport via L-type voltage-dependent Ca2+ channels) delayed the ACTH and cortisol responses to naloxone in the DM group without altering the magnitude of these responses. In contrast, nifedipine reduced but did not delay the ACTH and cortisol responses to naloxone in the control group. These findings suggest the presence of an abnormality of DHP- insensitive Ca2+ transport in the corticotrophs of DM patients. Pre-treatment with aspirin (which inhibits the cyclooxygenase pathway of arachidonic acid metabolism) resulted in an increased ACTH response to naloxone in the contro1 group, but a paradoxical decrease in the ACTH response of the DM patients. This finding implies that the interaction between arachidonic acid metabolites and ACTH secretion is abnormal in DM patients. The effects of nifedipine and aspirin on the HPAA are probably occurring at the pituitary level of the axis. The abnormal findings in the DM patients are likely to be due to altered cAMP-dependent protein kinase function in this condition.
The PTSD patients were studied by sequential injections of naloxone and AVP in separate dose-response protocols. Half of the PTSD patients had greater ACTH responses to the lowest dose of naloxone than did any of the control subjects. Detailed statistical analysis confirmed that these PTSD patients constituted a distinct subgroup, with greater ACTH and cortisol responses to naloxone than the other PTSD patients or the control subjects. However, there were no differences in the responses to AVP between the PTSD patients and the control subjects. These findings suggest that there is an abnormality in PTSD which may cause hypersensitivity to naloxone-stimulated CRH secretion, and that it is probably located at a supra-pituitary, rather than pituitary, level of the HPAA.
In conclusion, this thesis reports several findings on HPAA function in healthy control subjects, including the effects of nifedipine and aspirin, dose-response data for naloxone and AVP, and synergism (with regard to ACTH release) between naloxone and AVP. It also reports new abnormalities of HPA axis function in DM and PTSD which are probably related to the underlying pathophysiology of these conditions.
Vol 131 parts 3-4, pp. 119-120 [1998] |
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Establishing Very Low Speed, Disturbance-free Flow for Anemometry in Turbulent Boundary Layers
P.V. Lanspeary
Abstract of Thesis submitted for the Degree of Doctor of Philosophy, University of Adelaide
The thesis addresses problems encountered when establishing the very low air-flow speeds required for experimental investigations of the mechanisms of low-Reynolds-number boundary-layer turbulence. Small-scale motions in the near wall region are important features of turbulent boundary-layer dynamics, and, if these features are to be resolved by measurements in air with conventionally-sized hot-wire probes, a well-behaved canonical turbulent boundary layer must be developed at free stream flow speeds no higher than 4 m/s. However, at such low speeds, the turbulent boundary layers developed on the walls of a wind tunnel are very susceptible to perturbation by non-turbulent time-dependent flow structures which are produced in the laminar flow upstream of the test section.
Four different non-turbulent flow structures have been identified. The first is a result of quasi-two-dimensional separation of the laminar boundary-layer from the surfaces of the wind-tunnel contraction. Potential flow simulations show that susceptibility to this form of separation is reduced by increasing the degree of axisymmetry in the cross-section geometry and by decreasing the streamwise curvature of the concave surfaces. The second source of time-dependence in the laminar boundary-layer flow is an array of weak stream wise vortices produced by Görtler instability. The Görtler vortices can be removed by boundary-layer suction at the contraction exit. The third form of flow perturbation, revealed by visualisation experiments with streamers, is a weak large-scale forced-vortex swirl produced by random spatial fluctuations of temperature at the wind-tunnel inlet. This can be prevented by thorough mixing of the inlet flow; for example, a centrifugal blower installed at the inlet reduces the amplitude of temperature nonuniformity by a factor of about forty and so prevents buoyancy-driven swirl. When subjected to weak pressure gradients near the start of a wind-tunnel contraction, Görtler vortices in laminar wall layers can develop into three-dimensional separations with strong counter-rotating trailing vortices. These trailing vortices are the fourth source of unsteady flow in the test-section. They can be suppressed by a series of appropriately located screens which remove the low-speed-streak precursors of the three-dimensional separations. Elimination of the above four contaminating secondary flows permits the development of a steady uniform downstream flow and well-behaved turbulent wall layers.
Measurements of velocity in the turbulent boundary layer of the test-section have been obtained by hot-wire anemometry. When a hot-wire probe is located within the viscous sublayer, heat transfer from the hot-wire filament to the wall produces significant errors in the measurements of both the mean and the fluctuating velocity components. This error is known as wall-proximity effect and two successful methods are developed for removing it from the hot-wire signal. The first method is based on the observation that, if all experimental parameters except flow speed and distance from the wall are fixed, the velocity error may be expressed non dimensionally as a function of only one parameter, in the form ΔU+=ƒ(y+). The second method, which also accommodates the effect of changing the hot-wire overheat ratio, is based on a dimensional analysis of heat transfer to the wall.
Velocity measurements in the turbulent boundary layer at the mid-plane of a nearly square test-sectionduct have established that, when the boundary-layer thickness is less than one quarter of the duct height, mean-velocity characteristics are indistinguishable from those of a two-dimensional flat-plate boundary layer. In thicker mid-plane boundary layers, the mean-velocity characteristics are affected by stress-induced secondary flow and by lateral constriction of the boundary-layer wake region. A significant difference between flat-plate and duct boundary layers is also observed in momentum-balance calculations. The momentum-integral equation for predicted by the momentum-integral equation for a duct agree closely with measurements of the newly defined duct momentum thickness. Such agreement cannot be obtained in terms of standard flat-plate momentum thickness.
In duct boundary layers with Reynolds numbers (Re ) between 400 and 2600, similarity in the wake-region distributions of streamwise turbulence statistics has been obtained by normalising distance from the wall with the flat-plate momentum thickness, 2. This result indicates that, in contrast with the mean velocity characteristics, the structure of mid-plane turbulence does not depend on the proportion of duct cross-section occupied by boundary layers and is essentially the same as in a flat-plate boundary layer. For Reynolds numbers less than 400, both wall-region and wake-region similarity fail because near-wall turbulence events interact strongly with the free stream flow and because large scale turbulence motions are directly influenced by the wall. In these conditions, which exist in both duct and flat-plate turbulent boundary layers, there is no distinct near-wall or wake region, and the behaviour of turbulence throughout the boundary layer depends on both wall variables and on outer region variables simultaneously.
Vol 131 parts 3-4, pp. 121-122 [1998] |
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Molecular Recognition between DNA and CHIRAL Intercalative Metalloprobes
Kymberley A. Vickery
Abstract of a Thesis submitted for the Degree of Doctor of Philosophy, Macquarie University, NSW, 1998
A series of ruthenium(II) octahedral complexes comprising the chiral N4-tetradentateN,N-dimethyl-N,N'-di(2-picolyl)-1R*,2R*- diaminocyclohexane (R*R*-picchxnMe2) of the type Δ,Δ-cis-α and Δ,Δ-cis-β-[Ru(R*R*-picchxnMe2)-(bidentate)]2+ [where bidentate = bipy (2,2'-bipyridine), phen (1,10- phenanthroline), dpq (dipyrido[3,2-ƒ:2,'Sh]quinoxaline), phdi (9,10-phenanthrenequinone diimine), dip (4,7-diphenyl-1,10-phenanthroline) npdi (1,2-diiminonaphthalene) and dppz (dipyrido-[3,2-a:2,'3-c]phenazine)] has been synthesised. Resolution into α and β stereoisomers and Λ and Δ configurational enantiomers has been carried out on the complexes containing the phen, dpq and phdi ligands. General structural analyses of the isomerically pure products were undertaken using1HNMR, circular dichroism absorption spectroscopic methods. The tetradentate was found to be non-stereospecific in its coordination to Ru(II), yielding both α and β conformational geometries for each of the bidentates used, with the exception of npdi, for which only the α isomer was obtained.
The complexes were designed to interact with DNA via a reversible intercalative mode, where the bidentate component functions as the intercalating chromophore and the tetradentate governs binding selectivities through helical groove contacts. The chiral recognition abilities of nucleic acids towards the diastereomeric and enantiomeric forms of the cations were investigated using various forms of DNA. Nucleic acid sources employed include calf thymus DNA, synthetic self-complementary oligonucleotide fragments, the homo- and co-polynucleotides poly[dA]·poly[dT] and (poly[dG·dC])and plasmid as well as whole-cell bacterial DNA systems. Binding interactions were investigated by following the hypochromism induced in the visible absorption spectra of the complex cations upon addition of calf thymus DNA and selected polynucleotides. The complex-DNA adduct stoichiometries and equilibrium binding constants were determined and used to rank the intercalating ability of the different bidentate systems as phdi>dpq>phen. Bacterial mutagenesis activity assays were used to seek structure-activity relationships between the various α and β and Λ and Δ isomers in each of the bidentate systems. The results of these investigations correlate well with the ranking order obtained from the binding constant data. Poly[dA]·poly[dT] and (poly[dG·dC])2 polynucleotide forms and calf thymus were used to show that only minor nucleobase sequence selectivity exists between the four isomers of the [Ru(R*R*-picchxnMe2)(dpq)]2+ metalloprobes. Flow linear dichroism studies indicate the binding mode of action as predominantly intercalative for the dpq and phdi series metalloprobes, while the phen complexes were found to have an orientation indicative of groove binding to the host duplex. NMR studies of synthetic oligonucleotides interacting with various probe cations were used to show the main site of interaction on the complex, and their effects on the oligonucleotides. Metalloprobe self-association studies were carried out to demonstrate that significant p-stacking interactions occur in aqueous media for the cations based on the dpq and phdi chromophores.
Vol 132 parts 1-2, p. 37 [1999] |
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The Pathogenesis and Behaviour of Clinical Endocrinopathy in Multiple Endocrine Neoplasia Type 1
John R Burgess
Abstract of a Thesis Submitted for the Degree of Doctor of Medicine at the University of Tasmania.
Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant tumour syndrome characterised by poly-glandular parathyroid hyperplasia, pancreatic tumours and anterior pituitary neoplasia. The MEN 1 gene is believed to be a tumour suppressor gene and has recently been cloned. Genotype-phenotype correlations have not been identified thus far. This thesis sought to identify factors predicting the development and behaviour of endocrine tumours in patients with MEN 1. The patients studied derive predominantly from a large, multi-generational Tasmanian MEN 1 family (designated Tasman 1), of whom over 160 members carry a mutation of the MEN 1 gene. The prevalence, distribution and behavior of pituitary disease, enteropancreatic neoplasia, adrenal tumours and parathyroid neoplasia has been examined. Acromegaly is often been cited as a cardinal pituitary manifestations of MEN 1. There is a complete and unexpected absence of acromegaly in the Tasman 1 family, suggesting that either the expression of acromegaly in Tasman 1 is attenuated or that the previously reported high prevalence of acromegaly in other MEN 1 families is the result of inadvertent inclusion of patients with MEN 1 phenocopy. Both factors appear contributory, as correlation of genetic and clinical screening data indicates conventional phenotypic criteria for MEN 1 diagnosis over-estimate the prevalence of genotypic MEN 1. The distribution of prolactinoma and enteropancreatic malignancy in the Tasman 1 family also suggests the involvement of genetic modifier factors in MEN 1 tumour pathogenesis. These tumour species occur frequently in some branches of the Tasman 1 family, whilst they are relatively uncommon in other parts of the kindred. Given common ancestry of the MEN 1 disease allele in Tasman 1, disease clustering can not be explained by MEN 1 allelic heterogeneity. These observations suggest that additional genetic loci inherited separately from the primary MEN 1 locus have an important role in modulating tumorigenesis. Adrenal tumours in MEN 1 appear to develop in response to circulating growth factor(s) secreted by enteropancreatic tumours. Moreover, a propensity for parathyroid hyperplasia to recur despite extensive surgical resection of parathyroid tissue suggests a role for circulating growth stimuli in MEN 1 tumorigenesis.
In conclusion, this thesis shows that MEN 1 gene expression is modified by a variety of genetic and biological factors. The findings have implications for patient management as well as providing an insight into the mechanisms of tumour pathogenesis.
Vol 132 parts 1-2, p. 38 [1999] |
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Conventional and Topographic Electroencephalography and Somatosensory Evoked Potential Studies in Ischaemic Stroke
Monica Anne Hamilton-Bruce
Abstract of a Thesis Submitted for the Degree of Doctor Of Philosophy at Adelaide University.
The purpose of this prospective study was to assess the diagnostic and prognostic value of early electroencephalography (EEG) and somatosensory evoked potential (SEP) studies in cortical and non-cortical ischaemic stroke. Both conventional and topographic/quantitative studies were performed. A parallel study was carried out on healthy volunteers to provide an effective control. Equipment and quantitative EEG (qEEG) variability was also assessed.
Equipment was tested using an external calibration source, from which some amplitudes fell outside the ñ4% specified machine limits; a customised software upgrade rectified the problem. Voltage mapping showed that a single colour change could represent a variation of 1% to 25%. Intra-and inter-operator and intersession qEEG studies showed that most variability occurred in Absolute Power, but no significant difference was detected between 3 operators.
Fifty-one unselected acute ischaemic stroke patients were assessed clinically. All underwent non-contrast computerised tomography (CT), 16-channel EEG, 21-channel topographic qEEG, 3-channel SEP and 21-channel topographic SEP studies within 48 hours of the stroke; forty-five underwent all tests 4 to 15 days later. Final stroke classification was based on full clinical assessment, including the later CT. Clinimetric assessment included an early and 3 month Barthel Index (BI). Sixty-five healthy volunteers underwent the above electro-physiological studies after a clinical assessment; fifty-one were studied 5 to 16 days later.
Seventy-three percent of the patients were considered to have had unilateral cortical stroke and logistic regression showed that the tests most discriminating between cortical and non-cortical stroke were qEEG and CT in the first session and qEEG in the second session, at the 0.05 level. Conventional and topographic SEPs were independently associated with BI outcome in the first session, while for the second session this association applied only to conventional SEPs. Models were developed that were predictive of group (cortical/non-cortical) and outcome.
In conclusion, topographic qEEG, reflecting altered brain function after stroke, was useful in distinguishing between cortical and non-cortical ischaemic stroke, while conventional and topographic SEPs proved useful indicators of functional outcome.
Vol 132 parts 1-2, pp. 39-40 [1999] |
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Capillary Zone Electrophoresis: Studies on Separation Selectivity of Inorganic Anions
Anthony H. Harakuwe
Abstract of a Thesis Submitted for the Degree of Doctor of Philosophy at the University of Tasmania.
Parameters influencing the separation selectivity of low molecular-mass anions using free-solution reversed electroosmotic flow capillary zone electrophoresis (CZE) have been studied. First, detailed preliminary investigations were performed to address two major limitations of CZE, namely, imprecision in migration times and variability of phosphate response. A capillary conditioning regime suitable for the generation of stable migration times and optimal phosphate response was developed. Also, it was established that dried quaternary ammonium electroosmotic flow (EOF) modifiers generated more stable migration times and gave improved resolution.
Second, a wide range of selectivity-influencing parameters was studied. These parameters included electrolyte pH, EOF modifier chain length, nature of the EOF modifier counter-anion, EOF modifier concentration, binary EOF modifier mixtures, type of indirect detection probe, probe concentration, 1-butanol as an electrolyte additive, and instrumental variables (e.g. detection wavelength and separation voltage). The trends of migration order observed with the above parameters are discussed and possible mechanisms outlined. Major migration order changes were caused by pH and EOF modifier effects. Electrolyte pH variation changed the migration order of weak acid anions at pH values close to their pKa points by altering their charge-to-mass ratios. Migration order changes due to either increased or reduced ion-pairing effects were pronounced for lipophilic anions and could be induced particularly with EOF modifier changes, electrolyte concentration and 1-butanol as additive. Migration order changes due to increased effective charge of anions were influenced particularly by pH, 1-butanol as additive, and electrolyte ionic strength.
Third, information from the above studies was applied to the separation of inorganic anions in samples having varying levels of matrix complexity, e.g. tap water, Bayer liquor, seawater, acid- digested concrete, toothpaste, urine, a formulation for prevention of gall-stone formation, corned beef, and Antarctic saline lake water. Analytical performance characteristics are discussed for the separation of anions in Bayer liquor, concrete, and toothpaste.
The highlights of this study were that the useful pH range of chromate-based electrolytes could be extended by 20% by incorporation of 1-butanol in the electrolyte; the resolution between fluoride and phosphate could be improved by over 400% making possible the separation of 1 μg.mL-1 fluoride in the presence of over 800 μg.mL-1 phosphate, and the use of binary EOF modifier mixtures was introduced and applied to the analysis of Bayer liquor. Two electrolyte compositions capable of simultaneously separating chloride, sulfate, oxalate, malonate, fluoride, formate, phosphate, succinate, tartrate, carbonate, and acetate in under 4 minutes were identified. Calibrations were linear in the range 1-10 μg.mL-1, detection limits as low as 0.09 μg.mL-1 were obtained, and near quantitative recoveries (except for phosphate) were recorded.
Vol 132 parts 1-2, p. 41[1999] |
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The Management of Regional Economic Development Organisations with a Particular Emphasis on Funder Relationships
Helen Monks
Abstract of Thesis for the Degree of Doctor of Philosophy at the University of New England, Armidale.
The study aims to assist understanding of the management and organizational behaviour of regional development organisations in non-metropolitan Australia. The objective is to find new methodologies for studying regional development. The study will increase stakeholders' knowledge of appropriate management techniques.
This study has been undertaken when Australia is experiencing rural/urban and rural/coastal population movements exacerbated by difficult economic conditions in inland areas. Maintenance of the economy in rural communities is the background to this work.
The theoretical context adopted for the study proposes that development organisations are entities operating within an environment which exercises political economic and social demands (an open systems view). However, the open system is modified here by the addition of permeable organisational boundaries.
The style of the thesis is empirical and multi-disciplinary rather than theoretical. Disciplines such as government, non-profit sector management, regional economic development and organisation theory contribute metaconcepts and diverse perspectives. A modified case study method is applied to two organisations in New South Wales, one government owned and one community-based non-profit. A new analytical tool compares the impacts of five critical incidents upon each organisation, by their effect and source.
A comparison of summarised case study information suggests that organisational behaviour during the critical incidents differed distinctly. Specifically the non-profit organisation appeared to be more evenly: balanced than the government organisation in the quantity of its dealings with all stakeholders. Qualitatively, the former also had more positive transactions overall. Further, the government organisation appeared to have more negative transactions in total than the non-profit.
Strategic management of permeable organisational boundaries and of external relationships is touted as being significant for organisational independence and viability. Five management factors are proposed as a framework for balanced proactive management. Finally, the study canvasses possible productive roles for stakeholders in their support of regional development organisations.
Vol 132 parts 1-2, pp. 43-44[1999] |
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A Study Of The Scaling Behavior Of Some Cr2O3 Forming Alloys With Relevance To Inter-connect Plates For Solid Oxide Fuel Cells
Firoozeh Rabbani
Abstract of a thesis submitted for the Degree of Doctor of Philosophy at the University of South Australia.
Corrosion of metallic parts in low partial pressures of oxygen occur in oil and coal gasification processes, high temperature gas cooled reactor (HTGR) systems, fuel cells and fluidized bed combustion environments. However, there has been a lack of systematic work comparing/contrasting oxidation in air (high partial pressures of oxygen, high pO2) and at low pO2.
In this thesis the scaling behavior of some chromia forming alloys that had been used as metallic interconnects or current collectors for Solid Oxide Fuel Cells (SOFC) have been investigated. The oxidation behavior of three 'superalloys', five laboratory cast nickel-chromium binary alloys, and pure chromium was assessed in air and low partial pressures of oxygen simulating on a small scale the environments encountered at the anode and cathode of a SOFC. Initially, two partial pressures of oxygen were studied using air and a hydrogen/water mixture thereby excluding the effects of carbon and sulfur. The emphasis in this study was on the differences that arose as a result of changes in the pO2 and alloy composition, in particular chromium content. In air, nitrided layers were noted on some alloys. Three temperatures were considered 880oC, 930 oC and 980 oC with the objective of obtaining Arrhenius plots and activation energies. Evaluations were kept constant for both environments and made after 4, 49, 100 and 225 h oxidation time. Weight gain data were obtained and scale thickness measurements were made (using an image analysis system) on selected samples to constitute the kinetic data. The validity and relevance of the kinetic data obtained using these two parameters were evaluated.
Metallographic observations, SEM, EDS, EPMA, XRD, XPS, and AFM were selectively used to obtain information about the morphology and composition of the scales formed. This information was used to draw out empirical differences as a result of variations in the pO2 and temperature.
The results indicated that the chromium content of the binary alloys determined the oxidation kinetics and oxide morphology developed (including internal oxidation) in air and low pO2. In air, the scale compositions were further affected by the bulk chromium content. Values for the parabolic rate constant based on weight gain, kp, for the oxidation of the binary alloys in low pO2 ranged from 10-13 to 10-9 g2.cm-4.s-1. The rate constant based on scale thickness, ks, where measured, was of the order of 10-13 cm2/s. The value for kp in hydrogen/water increased with increase in temperature but the change did not appear to be as great as that observed for air oxidation. The kp of pure chromium was higher in air than in low pO2.
Values of kp for the commercial alloys were within the limits quoted for chromia formers, i.e. 10-13 to 10-12 g2.cm-4.s-1. The ks values ranged from 10-14 to 10-13 cm2/s. Oxidation in hydrogen/water yielded kp values which were comparable in magnitude to air oxidation, but ks values were lower than their air counterparts. The activation energy, Q, for the oxidation of the commercial alloys in air and low pO2 ranged from 307 to 193.6 kJ/mol calculated using kp. The limits of Q based on measurements of scale thickness were 266.2 and 31.1 kJ/mol.
The implications of these and other results were discussed in terms of alloy composition, exposure time and temperature, and the type of gaseous environment. Links were made to factors such as chromium content, alloy microstructure, and effect of minor additional elements on the oxidation kinetics and morphology where possible. The oxidation of the binary alloys in the hydrogen/water environment was compared to the oxidation of an alloy containing a noble metal. The effect of alloying chromium was highlighted. Variations in the kinetics were used to support different defect models for the oxidation of chromia in air and low pO2.
The initial stages of oxidation were studied for Ni20Cr, Ni30Cr, Ni80Cr binary alloys and for one commercial alloy. This information when correlated with the effects of heating procedure on the nucleation of oxides helps elucidate the mechanism of oxide growth. The surface application of cerium and the use of Au markers and immersion in an alumina pack were additional experiments to further elucidate the mechanics of oxidation. Finally a model has been presented for the oxidation mechanism of the commercial alloys incorporating existing hypothesis regarding oxide development.
Vol 132 parts 1-2, pp. 45-46 [1999] |
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Thermodynamic and Dielectric Properties in Modulated Two-dimensional Electronic Systems
Seán Stewart
Abstract of a Thesis Submitted for the Degree of Doctor of Philosophy at the University of Wollongong, Wollongong.
In this thesis we investigate the influence of an additional periodic modulation potential which is weak, either electric or magnetic in nature, and spatially modulated along one dimension, on the equilibrium thermodynamic and dielectric response properties of a two-dimensional electron gas in the presence of an externally applied perpendicular magnetic field.
The application of an additional modulation potential results in a broadening of the Landau level energy spectrum into bands whose widths oscillate as a function of the externally applied magnetic field. Such oscillations are found to reflect the commensurability between the two different length scales present in the sys-tem, namely the cyclotron diameter at the chemical potential and the period of the modulation. We show that such commensurability effects are also to be found in all thermodynamic quantities of the system which, in the case of a magnetic modulation, are shown for the first time. They appear at low magnetic fields as an amplitude modulation of the well-known de Haas-van Alphen-type oscillations, familiar from the homogeneous two-dimensional electron gas system in an external magnetic field which may or may not be resolved depending on temperature, and are only weakly dependent on temperature. Their origin is attributed to the oscillations occurring in the bandwidths and are consequently completely different in origin from the usual de Haas-van Alphen-type oscillations. We also find that the resulting commensurability oscillations in each thermodynamic function exhibit well-defined phase relations between the electric and magnetic modulations except in the case of the orbital magnetisation and the orbital magnetic susceptibility.
The dynamical dielectric response function and collective excitations for such weak spatially modulated systems are also calculated for within the random-phase approximation. It is found that the dynamical dielectric response function is not only broadened by the additional spatial modulation, it also contains a series of subsingularities at the band edges. The origin of the new subsingularities is related to the transition energies near the van Hove singularities of the energy bands attributed to the modulation-induced broadening of the energy spectrum. This broadening, being non-uniform, leads to the reintroduction of particle-hole pair excitations into the dielectric response function. Such broadening of the response function is also found to modify the magnetoplasmon modes of such systems over their unmodulated counterpart. The broadened Landau levels allow for a new low-frequency intra-magnetoplasmon mode to occur which exhibits oscillatory behaviour as a function o-l the external magnetic field. It is also shown that additional modulation-induced oscillations occur in the inter-magnetoplasmon spectrum, which is split into the principal and the Bernstein modes. All such oscillations reflect the ubiquitous commensurability oscillations now found in these weakly modulated systems as a function of the external magnetic field.
Vol 132 parts 1-2, pp. 47-48 [1999] |
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"Where The Spirits Meet" A History of The National Museum And Art Gallery, Waigani, Papua New Guinea
Christina Wright
Abstract of a Thesis submitted for the Degree of Master of Arts (Hons) at the Charles Sturt University, Bathurst Campus.
This thesis examines the history of collecting cultural material during the first century of colonial impact, 1884-1984, beginning with the British colonization of the territory in 1884; the use of temporary museums established in Papua by Australian government officials after it was proclaimed a Territory of the Commonwealth in 1906; to the Independent State of Papua New Guinea in 1975 followed by the establishment of the permanent Papua New Guinea National Museum at Waigani in 1977.
The notion of a museum was brought to Papua and New Guinea with the English language by government officials, explorers and missionaries who came for a variety of reasons. The new residents of the islands began collecting specimens of cultural material regarded as 'curios' from the colony before it was greatly altered or completely lost with the encroachment of European civilization. Many of these artefacts are stored in museums and private collections throughout the world. A small band of the government officials collected cultural material with the intention that it be returned at a later time to Papua New Guinea.
In traditional times village societies had special places for particular and religious artefacts associated with their way of life. The goal of the carvers and artists was not noble simplicity but multiplicity of visions, as the objects combined formal discipline with diversity of motifs for their own needs. Nothing was left to chance: to the villagers, all things were linked and merged into one another. The term 'museum', a building used for the storage and exhibition of objects, has been embraced by Papua New Guineans to take over the functions of their own traditional communal houses. This pre-existing cultural attitude towards collections of objects of social importance made the western 'museum culture' easy for Papua New Guineans to assimilate.
Early colonial officers, such as MacGregor, Murray, Cleland, McCarthy and others established policies that sought to protect and preserve the country's cultural heritage until Papua New Guineans could implement their own cultural policies for the nation. These early 'Heads of Government' took advantage of the work done by the anthropologists, Haddon, Pitt-Rivers, Seligman, Williams and others in seeking to understand the ways of the indigenous people of the new colony. The role played by the professionals (both from outside the Museum and as employees) has been very influential in enlisting Australian and international aid, including UNESCO support. Despite the good intentions behind the National Cultural Property (Preservation) Act to protect the country's cultural heritage, the Museum has encountered many difficulties in enforcing the law.
When contrasting the position between Papua New Guinea's National Museum and museums of other Pacific nations, it can be seen that early colonial officials in Papua New Guinea have been most supportive and protective of the culture and the development of museums for the people. This has not always been the case with other Pacific Islands. There were times when those involved with the National Museum succeeded in their objectives and other times when some poor decisions were made. However, the basic policies of promoting national identity and encouraging people's pride in their own individual cultures has always been of paramount importance to those involved with the Museum. The Constitution of the Nation acknowledges the noble traditions passed from one generation to another. (See Appendix 1 ).
After Independence, the historical account of the progressive development of the Papua New Guinea National Museum was followed by a setback in 1984 when the Head of Government support was withdrawn and funding to the Museum severely cut.
It will be seen that the Papua New Guinea National Museum has been forged out of British Imperial culture and early colonial foresight. There has been a blending of 'native' and European cultures by Papua New Guineans to meet their own particular cultural needs. Sir Bernard Narokobi, while President of the Museum Board of Trustees, said 'We should start with our ways and make use of other people's ways to uplift and improve upon our ways'1
The Museum reflects the nation's cultural background aesthetically and spiritually and it ' stands as a monument to the past, a source of study to the present and an inspiration to the future.2 It is a place 'where the spirits meet'.3
Notes
- C. B. Narokobi, The Melanesian Way: Total Cosmic Vision of Life, Institute of PNG Studies, Port Moresby, 1980, p.12
- Michael Somare, President, board of Trustees, Papua New Guinea Public Museum and Art Gallery, Annual Report of the Tnjstees, 1975-76, Port Moresby, p.ii
- Mr Geoffrey Mosuwadoga, in discussions with Mrs. Chris Wright, referred to the National Museum as the place 'where the spirits meet'.
Appendix 1
The following extract from: "The Constitution of the Independent State of Papua New Guinea" acknowledges the noble traditional wisdoms passed from one generation to another:
"We the people of Papua New Guinea
| United in one nation | ||
| Pay homage to the memory of our ancestors the source of our strength and origin of our combined heritage | ||
| Acknowledge the worthy customs and traditional wisdoms of our people which have come down to us from generation to generation | ||
| Pledge ourselves to guard and pass on to those who come after us, our noble traditions... " |
"Therefore let us live and be guided by our Constitution."
Vol 132 parts 3-4, pp. 111-112 [1999] |
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Geology And Geochemistry of The Wallendbeen Area, N.S.W.
Ian Cooper
Abstract of a Thesis Submitted for the Degree of Master of Science, University of Sydney 1998
The geology of the Wallendbeen area (400km south west of Sydney) is dominated by the Silurian Young Batholith and (?)Cambro-Ordovician Jindalee Group. The Jindalee Group consists of deformed and metamorphosed basalt, mafic volcaniclastic rocks, gabbro, ultramafic rocks, and banded quartz - 150 Fe - 150 Mn meta-chert defining an ocean floor environment. Although samples are altered, whole rock major, trace and rare earth element data are consistent with a primary back-arc basin setting. A second association within the Jindalee Group is composed of finely bedded quartzose psammite and psammopelite that bear similarities to the Middle Ordovician Wagga Group. These quartzose rocks have been derived from a continental source and are part of an extensive turbidite fan covering the Lachlan Orogen in the Ordovician.
Both the mafic and quartzose rocks share a common metamorphic and structural history that involves two periods of tight to isoclinal folding. The first deformation event is correlated with the Early Silurian 'Benambran Orogeny' where peak metamorphic conditions are transitional to amphibolite facies at ~500 OC and 300 MPa, indicating a depth of burial of 10-12 km. The second deformation involves tight to isoclinal upright folding with lower greenschist facies conditions. This event is ascribed to the 'Bowning Orogeny' that is constrained to the period ~420 to 417 Ma in the Wallendbeen area.
An 8 km long fault bounded wedge of andesitic volcanic rocks (Yandilla Volcanics) occurs within serpentinites at 'Fontenoy'. The Yandilla Volcanics comprise andesitic volcanic rocks, phyllite, banded chemical sedimentary rocks and a small hornblende diorite. The whole rock major, trace and rare earth element geochemistry display a continental arc signature and the Yandilla Volcanics are correlated with the Mid-Silurian Blowering Formation in the Cullinga area.
Both the Jindalee Group and the Yandilla Volcanics show the effects of contact metamorphism and boron-potassium metasomatism due to intrusion of the Young Granodiorite that postdates 'Bowning Orogeny' deformation. The Young Batholith is a large granitic body (210 km north-south by 40 km east-west) that is characterised by peraluminous S-type geochemistry. The intrusion is dominated by grey biotite granodiorite with rare alkali feldspar leucogranite. Metasediment xenoliths and tonalitic igneous enclaves that represent frozen droplets of a more mafic magma are abundant. Tectonic discriminant diagrams and palaeogeographic reconstructions indicate a volcanic arc setting for the pluton. The Young Granodiorite is the product of partial fusion of Cambrian oceanic crust (Jindalee Group equivalents) and Ordovician metasediment with a mantle subduction component.
The tectonic development of the region commenced with the formation of a (?)Cambrian back-arc basin containing the Jindalee Group. This oceanic crust was covered by an enormous turbidite fan in the Ordovician, then both units were strongly deformed and metamorphosed in the Early Silurian 'Benambran Orogeny' that produced continental thickness crust. Mid Silurian back-arc transtensional rifting exhumed the Jindalee Group from ~12 km. Continental arc volcanism above the Young Granodiorite produced the Blowering Formation and Yandilla Volcanics. These units along with the Jindalee Group basement were deformed by the 'Bowning Orogeny' just prior to intrusion of the Young Granodiorite into the upper crust.
Vol 132 parts 3-4, pp. 113-114 [1999] |
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Thesis Abstract: Air Movement in the Human Sleeping Environment and Sudden Infant Death
John Andrew Corbyn
Abstract of a Thesis submitted for the Degree of Doctor of Philosophy Murdoch University, W.A. 1999.
Searches for disease or abnormality within the infant have not led to an explanation for many Sudden Infant Death Syndrome or SIDS cases. The present study considers SIDS in terms of the microclimate at the face and the inhalation of previously exhaled air. Inhalation of previously exhaled air is also known as re-breathing. The physiology of sleeping in re-breathing conditions and SIDS is discussed. Statistical data concerning SIDS and environmental conditions is reviewed. The transport of carbon dioxide from and oxygen to the face is effected by jet action of the nose and other processes. Temperature, humidity, pollution (which affects aerosol formation), bedding arrangement, sleeping position and other conditions are significant. A simulator for studying sleeping environments is described. It was found that exhaled air can accumulate at the face of a sleeping infant. In some circumstances the carbon dioxide content of the inhaled air is above the industrial threshold limit of 0.5% with values of over 2% occurring.
Physiological mechanisms exist which allow that re-breathing of vitiated air can account for a proportion of SIDS cases. In particular a sleeping infant acclimatized to an atmosphere with excess carbon dioxide may suffer from a reduced lung ventilation rate [in medical terms a reduced minute volume] on subsequent exposure to a normal atmosphere. The associations between SIDS and particular environmental conditions were found to be consistent with re-breathing as a cause of SIDS. It is recommended that sleeping infants have unobstructed passage of exhaled air away from the face. Detailed safety precautions are given. It is clear that investigations of SIDS deaths should include physical model studies of the infant's sleeping environment; follow-up SIDS investigations should include searches for evidence of past exposure to continual re-breathing.
The present study aimed at establishing a formula that predicts the dimensional accuracy Sudden Infant Death, Crib Death (U. S. A. term for cot death), Cot Death and Overlaying (where baby dies in bed with mother) and now all described as SIDS, have been found to be more common in these circumstances: winter, low temperatures, high humidity, atmospheric pollution.
Explanation for a proportion of these deaths can be made in terms of the accumulation of exhaled air with excess carbon dioxide at the face during sleep. The result of continued sleeping in this environment is that the infant becomes acclimatized to a high carbon dioxide level in inspired air and the control of breathing becomes abnormal. Exhaled air from other persons or animals sleeping close to the face of the infant may also contribute.
| Conditions that make the retention of
exhaled air in the bed more likely:- *Soft bedding *Bulky bedding near the face *No draughts *Face down position *Damp or wet bedding *Confined cot, pram or bed *Unventilated mattress *Infant under bedding *High humidity (see note A) *Tobacco smoke, air pollution * Exhaled air directed into bed |
Conditions that make retention of exhaled
air near the face less likely:- *Hard bed *Thin bedding *Dry bed *Face up position *Draughts *No bottles, toys or obstructions *Not sleeping through the night *Not exposed to breath of others (note B) *Not sleeping between adults *Not to sleep against a wall *Mattress bedding not permeable *Breath to direct air away from the face. |
| Note A: | High humidity can result from climatic influences, unflued gas or kerosene heaters and evaporative air conditioners. |
| Note B: | If in bed with adults the infant must not be down in the bed and exposed to a pool of exhaled air from the adults. Always make sure that there is a clear space around the head so that the baby has access to fresh air. The breath coming from the mouth or nose is not obstructed so that it can move freely away from the face. Making sure that the baby gets fresh air will provide protection against the dangers of exhaled air at the face even if other conditions are bad. |
Vol 132 parts 3-4, p. 115 [1999] |
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Thesis Abstract: Prediction of the Dimensional Accuracy of Small Extra-coronal Titanium Castings
Chun Yu Danny Low
Abstract of a Thesis Submitted for the Degree of Master of Science in Dentistry at The University of Sydney.
The present study aimed at establishing a formula that predicts the dimensional accuracy of small extra-coronal titanium castings. The experimental component of the research started with determination of the metal shrinkage to be compensated. This was followed by the prediction of dimensional accuracy firstly using mould expansion data from manufacturers and then those from laboratory measurements. Three investments available for titanium casting were used. The dimensional accuracy of dental castings has long been assessed using specially designed metal dies. Although full crown designs are very common for this purpose, the demand for porcelain veneered restorations is increasing and a new die design for this type was also introduced in the present study.
Finally, a statistical model was developed to examine the contribution of setting and thermal expansion to the accuracy of castings. It was hoped that the statistical approach would provide an answer to the hypothesis that the contribution of setting expansion of investment is little in the fabrication of small extra-coronal castings.
Vol 132 parts 3-4, p. 116 [1999] |
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A Study of Some Ternary Tetradentate Complexes As Phenanthrene-based Chiral Metallointercalators
Susan F. Murphy-Poulton
Abstract of a Thesis submitted for the Degree of Master of Science, Macquarie University, NSW, 1998
The main aim of this research was to investigate the synthetic and structural chemistry of the ternary Ru(II)-picchxn-phdi chelate system and to characterise the interaction of these chelates with DNA. The complex cations synthesised and characterised were rac-β-[Ru(picchxn)(phdi)]2+, Δ-β-[Ru(S,S-picchxn)(phdi)]2+, Λ-β-[Ru(R,R-picchxnmi)(phdi)]2+, rac-β-[Ru(picchxnmi) (phdi)]2+, Λ-β2-[Ru(R,R-picchxnmi)(dmso)Cl]+. Here picchxn represents N,N'-di(2-picolyl)-1R*,2R*-diaminocyclohexane, picchxnmi refers to the monoimine form of the same, phda is 9,10-diaminophenanthrene, and phdi refers to the diimine form of the same. The compounds were obtained as their Cl- or PF6- salts. The interaction of each of the phdi complexes isolated with calf thymus DNA was studied spectroscopically by visible absorbance hypochromism and circular dichroism (CD) titration methods. The absorbance titrations show DNA to be saturated at ca 3.6 base pairs per ruthenium complex for rac-β-[Ru(picchxn)(phdi)]2+ and Δ-β-[Ru(2+, and ca 3.9 for Λ-β-[Ru(R,R-picchxnmi)(phdi)]2+. The calculated intrinsic equilibrium binding constants range from 5.6-13 x 104p, and the red shifts with accompanying hypochromism observed indicate that the complexes intercalate. The plotted extrema in CD titrations reveal the existence of two inflection points suggesting that more than one mode of binding exists in these systems. Titrations performed on racemic complexes suggest a Δ enantioselectivity. The red shift and positive induced CD (ICD) provide further evidence as to the mode of binding being intercalation. Equilibrium dialysis and ethanol co-precipitation experiments for the racemic complexes in the presence of calf thymus DNA also reveal a small degree of enantiomeric selectivity for the Δ enantiomer, with the optical enrichment values ranging between 4-18%. Thermal denaturation studies on free DNA and DNA-complex adducts show significant increases in Tm upon binding of the cations, confirming that intercalation is the predominant binding mode. There is also an indication that the DNA interaction of these complexes is base sequence selective. Molecular modelling reveals that the one amine proton of picchxn is well positioned for H-bonding with O6 of a guanine residue when the complex is intercalated into a G-C site, which may be the cause of this selectivity.
Vol 132 parts 3-4, p. 117 [1999] |
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Thesis Abstract: Effect of Exercise on Diffusing Capacity in Patients with Cystic Fibrosis
Rhonda Orr
Abstract of a Thesis Submitted for the Degree of Master of Exercise and Sport Sciences at The University of Sydney
Regular exercise has been increasingly emphasised as an important component in the management of the patient with cystic fibrosis. However, exercise imposes great stress on the pulmonary system and patients with cystic fibrosis can vary markedly in their exercise response. Patients with spirometry in the normal range exhibit a normal response to exercise. Patients with severe lung disease experience exercise intolerance, with hypoxaemia, hypercapnia and increased end-expiratory lung volume.
One aspect of pulmonary investigation is diffusion of gases during exercise. Diffusing capacity of the lung for carbon monoxide (DLCO) increases with exercise in the normal population, but has not been demonstrated in patients with cystic fibrosis. The limited number of studies in this area give conflicting results, both at rest and after completion of exercise. Reports suggested that there may be a diffusing defect or diffusion limitation during exercise in patients with cystic fibrosis. To the author's knowledge, no studies have directly measured DLCO during exercise in patients with cystic fibrosis, who have not undergone heart-lung transplantation.
The aim of this study was to measure DLCO directly during exercise and to determine if there was a normal increase with exercise. Single-breath DLCO was measured in twelve patients with cystic fibrosis and six normal subjects, at rest and during incremental steady state exercise to exhaustion, with five minute rest intervals between workloads. During exercise, all patients with cystic fibrosis significantly increased their single-breath DLCO from rest, suggesting an ability to recruit alveoli and pulmonary capillaries by expanding the pulmonary capillary bed effected through an increase in cardiac output. Moreover, the rise in the diffusion rate was similar to that of normal subjects. There was no evidence for diffusion limitation during submaximal exercise in patients with cystic fibrosis.