UQ Theses Collection (RHD) - UQ staff and students only - UQ eSpace

Biomarkers of Motor Neurone Disease: Neurophysiological studies of lower motor neuron degeneration

Fusun Baumann — 2012-05-24T00:00:00Z

Motor neurone disease (MND) is a fatal disease characterized by relentless degeneration of both upper motor neurones (UMN) and lower motor neurones (LMN) leading to progressive muscular paralysis, with death usually occurring 1 to 5 years after the onset. Despite the recent advances in research, the cause of motor neuron death and the pathological determinants of disease progression in MND still remain poorly understood. There is no efficient treatment of the disease and further clinical trials are required to test potential therapies. Clinical heterogeneity is a recognized feature of MND and is reflected in differences in survival time and rate of progression. From a pathophysiological point of view, this raises the question of whether MND is a single disease entity or a syndrome of different clinical entities arising from distinct biologic mechanisms. Clinical assessment by way of the traditional clinical examination remains the best way to assess neurodegeneration and to follow the process in real time but is not able to detect subclinical UMN or LMN involvement. Therefore, objective biomarkers of UMN and LMN dysfunction are useful not only as endpoint measures sensitive to early therapeutic effects but have the potential to shed light on the disease pathogenesis in MND and might also resolve complexities of clinical heterogeneity in clinical trials. We hypothesized that Bayesian motor unit number estimation (MUNE) is a sensitive biomarker of lower motor neuron degeneration in MND. We performed serial studies in a large cohort of MND patients to evaluate motor unit (MU) loss in different regions of the spinal cord and among clinical subtypes of MND The half life of MUs determined by serial Bayesian MUNE was able to demonstrate selective vulnerability of different motor neuron pools during the disease process and the spread of disease from the site of onset. It also distinguished the clinical subtypes with different survival time. Our findings were supported by previous reports using clinical and neuropathological methods in human subjects and animal models of MND. Therefore Bayesian MUNE has the potential to be a sensitive biomarker of disease process in MND subjects. Furthermore, since both the MU number and size have not been considered in previous MUNE methods, Bayesian MUNE provides useful information about MU sprouting in MND. Our results of serial studies of Bayesian MUNE have confirmed its potential as a biomarker of disease progression and as a reliable, reproducible, practical and tolerable method.

Biomimetic Orientated Total Synthesis of Neovibsane Natural Products and Comparison of Synthetic Neovibsanes on Neurite Outgrowth Promotion in PC12 Cells

Annette Chen — 2010-06-09T00:00:00Z

Neovibsanin A and B are natural products which induced neurite outgrowth in PC12 cells. They belong in the neovibsane class under the rare vibsane natural product family, whose structures are characterized by polycyclic, polyoxygenated cores. Based on a proposed biosynthesis, the synthetic strategy towards neovibsanin A and B involved synthesizing a key enone intermediate. Initial investigation using this intermediate lead to the total synthesis of 2-O-methylneovibsanin H. Crucial to this concise synthesis was an acid-catalyzed, one-pot, four-step cascade reaction. Modifying the reaction condition leads to a different five-step cascade pathway, resulting in the total synthesis of 4,5-bis-epi-neovibsanin A and B. The synthetic trials and tribulations encountered on the road to these final compounds are explored. It is envisaged that other related neovibsane natural products may arise based on this synthetic sequence. 4,5-Bis-epi-neovibsanin A and B, as well as several other structural analogues collected during the synthesis, were biologically assayed using NGF-stimulated PC12 cells. All compounds induced a significant proportion of neurons to extend neurite processes compared to control cultures. The structure-activity relationship studies indicated that the tricyclic core, as well as the 3,3-dimethylacroyl enol ester side chain, may be responsible for promoting a biological response.

Biomineralisation and the role of polyelectrolytes: an investigation into the crystal growth of hydroxyapatite in the presence of polyelectrolyte additives

Coleman, Robert Jonathon — 2012-12-07T13:50:52Z

Biomolecular Engineering for Peptide-Based Biomaterials

Belinda Hartmann — 2010-10-12T00:00:00Z

Bioactive peptides that can self-assemble reversibly, in response to external stimuli, are at the core of a new breed of “smart” peptides that form a complex array of novel biomaterials with potential applications in fields including tissue engineering, nanoelectronics, functional surface coating and food production. The majority of future markets associated with peptide-based biomaterials are characterized by high volume and low cost economics. This has limited the deployment of these new biomaterials because the expensive, synthetic peptide production routes currently used by industry to produce commercial quantities of peptide therapeutics are not compatible with this cost dynamic. Consequently, this project aimed to contribute to ongoing efforts to achieve cost-effective, efficient and scalable means of producing peptide by utilizing recombinant DNA technology and microbial hosts. Three separate bioprocesses have been designed, investigated and reported in this thesis. The first process design is based on the insoluble expression of a peptide-concatamer fusion protein in a bacterial host, and represents an attempt at optimizing a conventional, commercially-available system to test its suitability as an industrial bioprocess. The second bioprocess utilizes a soluble expression system, also in a bacterial host, and exemplifies a substantial departure from traditional process designs for recombinant peptide production. A final methodology is described which employs a yeast expression host and relies on the incorporation of additional unit operations into an existing industrial bioprocess, to create a dual production route for a target peptide and a target protein. The key research findings in this body of work are related to the development of selective precipitation methods, which were employed throughout each of the described processes to various degrees. Simple organic solvents, salts and acids were used to exploit the property differences between peptides and proteins in order to selectively partition peptide from heterogenous mixtures. The selective precipitation methods devised successfully minimized the need for expensive and time-consuming chromatography processes which are ordinarily required to obtain high yields of pure peptide. In terms of recombinant peptide production, the Selective Solvent Precipitation (SSP) techniques developed as part of this PhD have genuine potential as an industrial replacement for expensive chromatographic unit operations that currently limit the cost-effectiveness of conventional production routes.

Biopsychosocial Correlates of Women's Mental Health: A Longitudinal Analysis of Self-Reported Mental Health Across Three Generations of Australian women

Smith, Nadine Elizabeth — 2008-07-01T00:00:00Z

Biostratigraphic research on the Yarral Basin and marine geology on the Great Barrier Reef

Maxwell, William Graham Henderson — 2010-09-21T00:00:00Z

Biosynthesis of bovine oviductal explants : correlation of bovine oestrous-associated glycoprotein (BOGP) to glycosaminoglycan (CAG) and total protein synthesis

Legaspi, Alberto G. — 2011-09-14T00:00:00Z

BIOSYNTHESIS OF CIRCULAR PROTEINS IN PLANTS

Saska, Ivana — 2008-11-21T00:00:00Z

Backbone cyclisation has the potential to improve the thermodynamic and biochemical stability of proteins. The discovery of backbone cyclised (circular) proteins in nature has therefore generated a great deal of interest, both in understanding the basic biology of the cyclisation process and in its prospective application to bio-engineering. Naturally occurring circular proteins have now been identified in bacteria, plants and animals but their biosynthesis remains poorly understood, especially in eukaryotes. The broad aim of this study was to gain insight into natural mechanisms of cyclisation by examining the biosynthesis of the cyclotides, a large family of plant-derived circular proteins. The cyclotides are topologically complex circular proteins produced by plants from the Rubiaceae and Violaceae families. To date over 100 cyclotide sequences have been identified, but their total number is predicted to be in the thousands. Structurally, cyclotides are characterised by the combination of a cyclic backbone and a cystine knot arrangement of their three disulfide bonds. This framework is exceptionally stable and allows cyclotides to tolerate thermal, chemical and biological conditions that would degrade most linear proteins. The compact structure of cyclotides, while very stable, complicates detection of the proteins and has impeded efforts to characterise cyclotide expression levels in plants. As a result, in this project an alternative method for the detection of cyclotides was developed using MALDI-TOF mass spectrometry. The method facilitates both the detection and quantification of cyclotides in heterogenous mixtures, and challenges current assumptions that MALDI-TOF mass spectrometry is exclusively a qualitative technique. The analysis of cyclotides was also augmented by the development of a transient assay for the expression of cyclotide genes in Nicotiana benthamiana, a plant which does not endogenously produce cyclotides. Cyclotides are expressed as part of linear precursor proteins from which they must be excised before cyclisation can take place. Based on sequence conservation, processing at the N-terminus of the cyclotide domain does not appear to be specific but at the C-terminus occurs almost exclusively following an Asn or Asp residue. A major watershed in understanding this process was the finding presented that plants which do not naturally contain cyclotides are capable of producing the circular proteins when supplied with cyclotide precursor genes. This result indicates that the biochemical machinery necessary for protein cyclisation is not unique to cyclotide containing plants, but is common to plants in general. The production of cyclotides was less efficient in the transgenic system, leading to the production of linear cyclotide forms not characteristically observed in cyclotide containing plants. An analysis of the evolution of the linear species over time revealed an aberrant C-terminal processing mechanism that competed with the cyclisation process. This showed that the substrate for cyclisation was an extended linear cyclotide including part of the C-terminal tail and indicated that cleavage of the asparaginyl bond at the C-terminus of the cyclotide domain occurred together with cyclisation. Subsequent work was therefore directed towards identification of an enzyme capable of cleaving asparaginyl bonds. Only one class of enzymes, the legumains, are known to specifically hydrolyse asparaginyl, and occasionally aspartyl, bonds. These enzymes are common in plants where they are alternatively called asparaginyl endopeptidases and vacuolar processing enzymes (VPE). In vitro studies demonstrated that VPE activity was responsible for asparaginyl bond hydrolysis in cyclotide containing plants and was also capable of cleaving synthetic cyclotide substrates at the C-terminal asparaginyl bond of the cyclotide domain. The C-terminal Asn residue was not targeted when part of a full length precursor protein, suggesting that VPE activity was limited to the late stages of processing. Two approaches were used to assess the effects of decreased VPE activity on cyclotide biosynthesis in vivo. Both the application of a VPE inhibitor directly into plant leaves and virus induced gene silencing of VPEs caused a decrease in the levels of circular protein produced upon expression of the cyclotide precursor in N. benthamiana. The decease in VPE activity also correlated with an increase in the linear cyclotide forms, consistent with previous findings that cyclisation occurs together with cleavage of an extended linear substrate. The identification of a VPE from a cyclotide containing plant was the first step towards characterising this mechanism. Further inhibitor studies pointed towards the involvement of a cysteine protease in processing upstream of the cyclotide domain and subsequent non specific trimming to the N-terminal cleavage site. In summary this study has provided important insights into the processing and cyclisation of cyclotides in plants. A mechanism for backbone cyclisation is proposed in which cleavage at the C-terminal asparaginyl bond of the cyclotide domain is coupled to cyclisation in a transpeptidation reaction catalysed by a VPE.

Biosynthetic cytochrome P450s

Stok, Jeanette Elizabeth. — 2007-08-24T00:00:00Z

Birds of passage : British seagoing naturalists and the Royal Navy in the nineteenth century

Wilkins, Ian Keith — 2007-08-24T00:00:00Z

Birth order, motives, occupational role choice and organizational innovation : an evolutionary perspective

Plowman, Ian Cameron. — 2007-08-24T00:00:00Z

BIRTHWEIGHT AND SUSCEPTIBILITY TO CHRONIC DISEASE

Issa Al Salmi — 2009-06-12T00:00:00Z

The thesis examines the relationship of birthweight to risk factors and markers, such as proteinuria and glomerular filtration rate, for chronic disease in postnatal life. It made use of the Australian Diabetes, Obesity and Lifestyle Study (AusDiab). The AusDiab study is a cross sectional study where baseline data on 11,247 participants were collected in 1999-2000. Participants were recruited from a stratified sample of Australians aged ≥ 25 years, residing in 42 randomly selected urban and non-urban areas (Census Collector Districts) of the six states of Australia and the Northern Territory. The AusDiab study collected an enormous amount of clinical and laboratory data. During the 2004-05 follow-up AusDiab survey, questions about birthweight were included. Participants were asked to state their birthweight, the likely accuracy of the stated birthweight and the source of their stated birthweight. Four hundred and twelve chronic kidney disease (CKD) patients were approached, and 339 agreed to participate in the study. The patients completed the same questionnaire. Medical records were reviewed to check the diagnoses, causes of kidney trouble and SCr levels. Two control subjects, matched for gender and age, were selected for each CKD patient from participants in the AusDiab study who reported their birthweight. Among 7,157 AusDiab participants who responded to the questionnaire, 4,502 reported their birthweights, with a mean (standard deviation) of 3.4 (0.7) kg. The benefit and disadvantages of these data are discussed in chapter three. The data were analysed for the relationship between birthweight and adult body size and composition, disorders of glucose regulation, blood pressure, lipid abnormalities, cardiovascular diseases and glomerular filtration rate. Low birthweight was associated with smaller body build and lower lean mass and total body water in both females and males. In addition low birthweight was associated with central obesity and higher body fat percentage in females, even after taking into account current physical activity and socioeconomic status. Fasting plasma glucose, post load glucose and glycosylated haemoglobin were strongly and inversely correlated with birthweight. In those with low birthweight (< 2.5 kg), the risks for having impaired fasting glucose, impaired glucose tolerance, diabetes and all abnormalities combined were increased by 1.75, 2.22, 2.76 and 2.28 for females and by 1.40, 1.32, 1.98 and 1.49 for males compared to those with normal birthweight (≥ 2.5 kg), respectively. Low birthweight individuals were at higher risk for having high blood pressure ≥ 140/90 mmHg and ≥ 130/85 mmHg compared to those with normal birthweight. People with low birthweight showed a trend towards increased risk for high cholesterol (≥ 5.5 mmol/l) compared to those of normal birthweight. Females with low birthweight had increased risk for high low density lipoprotein cholesterol (≥ 3.5 mmol/l) and triglyceride levels (≥ 1.7 mmol/l) when compared to those with normal birthweight. Males with low birthweight exhibited increased risk for low levels of high density lipoprotein cholesterol (<0.9 mmol/l) than those with normal birthweight. Females with low birthweight were at least 1.39, 1.40, 2.30 and 1.47 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases respectively, compared to those ≥ 2.5 kg. Similarly, males with low birthweight were 1.76, 1.48, 3.34 and 1.70 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases compared to those ≥ 2.5 kg, respectively. The estimated glomerular filtration rate was strongly and positively associated with birthweight, with a predicted increase of 2.6 ml/min (CI 2.1, 3.2) and 3.8 (3.0, 4.5) for each kg of birthweight for females and males, respectively. The odd ratio (95% confidence interval) for low glomerular filtration rate (<61.0 ml/min for female and < 87.4 male) in people of low birthweight compared with those of normal birthweight was 2.04 (1.45, 2.88) for female and 3.4 (2.11, 5.36) for male. One hundred and eighty-nineCKD patients reported their birthweight; 106 were male. Their age was 60.3(15) years. Their birthweight was 3.27 (0.62) kg, vs 3.46 (0.6) kg for their AusDiab controls, p<0.001 and the proportions with birthweight<2.5 kg were 12.17% and 4.44%, p<0.001. Among CKD patients, 22.8%, 21.7%, 18% and 37.6% were in CKD stages 2, 3, 4 and 5 respectively. Birthweights by CKD stage and their AusDiab controls were as follows: 3.38 (0.52) vs 3.49 (0.52), p=0.251 for CKD2; 3.28 (0.54) vs 3.44 (0.54), p=0.121 for CKD3; 3.19 (0.72) vs 3.43 (0.56), p= 0.112 for CKD4 and 3.09 (0.65) vs 3.47 (0.67), p<0.001 for CKD5. The results demonstrate that in an affluent Western country with a good adult health profile, low birthweight people were predisposed to higher rates of glycaemic dysregulation, high blood pressure, dyslipidaemia, cardiovascular diseases and lower glomerular filtration rate in adult life. In all instances it would be prudent to adopt policies of intensified whole of life surveillance of lower birthweight people, anticipating this risk. The general public awareness of the effect of low birthweight on development of chronic diseases in later life is of vital importance. The general public, in addition to the awareness of people in medical practice of the role of low birthweight, will lead to a better management of this group of our population that is increasingly surviving into adulthood.

Bivalves and the Bucephalidae: A parasitic system on the Great Barrier Reef

Bott, Nathan James — 2008-11-21T00:00:00Z

This study set out to examine, for the first time, both the molluscan intermediate and the teleost definitive hosts of a major assemblage of trematode parasites present on the Great Barrier Reef (GBR). The parasite taxon was the Bucephalidae which occur in piscivorous fishes as sexually reproducing adults and in bivalves as asexually reproducing stages. The goal was to characterise the overall richness of the system and to explore patterns of host-specificity. Because of the size of this fauna it was not possible to incorporate all the taxa found in this study. This thesis reports the results of a survey of bivalves from this region, taxonomic studies on several elements of the fauna of fishes, and efforts to link life-cycles between bivalves and fishes. I surveyed 2256 bivalve individuals (47 species, 17 families) from South-east Queensland, Heron Island (southern GBR) and Lizard Island (northern GBR). Infections of trematode species from three families, Bucephalidae, Gorgoderidae and Monorchiidae, were found. Overall prevalence of infection was 2.3%. The Bucephalidae (11 species) was the most commonly found family. A single gorgoderid infection was found from a venerid, Lioconcha castrensis. This is the first report of a gorgoderid from a marine bivalve and phylogenetic analysis suggests that the species belongs to the Gorgoderinae. Monorchiids (5 species) were found from Tellinidae and Lucinidae. All infections are new host/parasite records. I deduce that this study produced lifecycle information, but no actual identifications, for 10% of the species of trematodes that infect bivalves of Queensland marine waters. Prosorhynchoides apogonis n. sp. is described from the intestine of the apogonid Cheilodipterus macrodon from the southern GBR. This is the first bucephalid to be described from the teleost family Apogonidae. Prosorhynchoides lamprelli n. sp. is described from the intestine of the carangid Caranx papuensis from off Lizard Island, GBR. This is the first bucephalid to be described from Caranx papuensis. A new trematode genus, Grammatorcynicola n. g. (Dolichoenterinae), and two new species, G. brayi n. sp. and G. nolani n. sp., are described from the intestines of the scombrids, Grammatorcynus bicarinatus and Gr. bilineatus respectively. Grammatorcynicola n. g. differs from other dolichoenterine genera in having a simple sucker-like rhynchus, the ovary anterior to the testes and by not having a particularly thick cirrus-sac wall. Six new species of bucephalid trematodes from the prosorhynchine bucephalid genera Prosorhynchus Odhner, 1905 and Neidhartia Nagaty, 1937 are reported from the epinepheline serranid genera Cephalopholis, Cromileptes, Epinephelus and Variola from the GBR. Two species of Prosorhynchus and one Neidhartia are reported from Epinephelus spp., P. jexi n. sp. from E. quoyanus, P. lafii n. sp. from E. fuscoguttatus, and N. epinepheli n. sp. from E. maculatus. The other species are P. robertsthomsoni n. sp. from several species of Cephalopholis, P. conorjonesi n. sp. from Cromileptes altivelis, and P. milleri n. sp. from Variola louti. I examined three species of Plectropomus (Serranidae: Epinephelinae), Pl. laevis, Pl. leopardus and Pl. maculatus from off Heron Island and Lizard Island on the GBR. Nine bucephalid species from the Prosorhynchinae were found, three species of Neidhartia and six species of Prosorhynchus. The three species of Neidhartia, N. haywardi n. sp., N. plectropomi n. sp. and N. tyleri n. sp., are readily distinguishable by morphology. Two of the six species of Prosorhynchus (P. lesteri n. sp. and P. wrightae n. sp.) are easily distinguished from their other congeners by morphology but the other four species (P. adlardi n. sp., P. heronensis n. sp., P. munozae n. sp. and P. plectropomi n. sp.) are highly similar in morphology and were only distinguished convincingly by comparing their ITS2 rDNA sequences. Both P. adlardi n. sp. and P. wrightae n. sp. have also been found once in V. louti at Lizard Island. This is also the first study to identify life-cycle matches of the Bucephalidae using molecular techniques. I found two perfect life-cycle matches (identical sequences). The bivalve host of Prosorhynchoides lamprelli is a tellinid, Exotica clathrata; Rhipidocotyle sp. from the sphyraenid Sphyraena jello also has E. clathrata as its first intermediate host. Bayesian Inference Analysis shows that all seven species from bivalves that were sequenced belong to the Bucephalinae. Perhaps the most striking finding of the study was that one bivalve species, E. clathrata, was shown to harbour four separate species. Matching of ITS2 rDNA sequences between life-cycle stages is highly effective in circumstances of great richness such as the Great Barrier Reef. Based on my data collected, the total bucephalid species in the system is estimated to be 84.

Bivalvia of the super families Pholadomyacea and Pectinacea from the permian of Eastern Australia

Runnegar, Bruce. — 2010-09-01T00:00:00Z

Blood dendritic cells in surgery and breast cancer

Ho, Christopher Siaw Kang — 2011-12-21T00:00:00Z

Blooms of the toxic cyanobacterium Lyngbya majuscula in Moreton Bay: links to anthropogenic nutrients

Kathleen Ahern — 2010-06-09T00:00:00Z

The increased proliferation of benthic marine cyanobacteria of the Lyngbya genus in many tropical and subtropical systems worldwide is a concern due to the detrimental impacts these blooms can have on ecosystems, local economies and public health. While increasing nutrient loads from anthropogenic sources/activities has been hypothesised as the main cause, evidence to support this is limited. This hypothesis was explored by investigating blooms of the toxic, benthic cyanobacterium Lyngbya majuscula in a sub-tropical shallow coastal embayment (Moreton Bay) in southeast Queensland, Australia—where blooms have increased in frequency and severity. More specifically, the thesis aimed to investigate the role of nutrients in the physiology and growth dynamics of L. majuscula in Moreton Bay through examination of three main research questions. Examination of the spatial and temporal variations in the growth and nutritional status of L. majuscula in Moreton Bay (Research Question 1) was investigated by tracking natural summer blooms in northeastern Moreton Bay (Deception Bay) over two successive years. Detailed field observations, extensive biomass and tissue nutrient sampling (every 10–14 days) and a three-dimensional model were used to map the change in areal extent, biomass and tissue nutrients over the course of the blooms. The results demonstrated the innate ability of L. majuscula to rapidly spread and generate massive amounts of biomass, with the peak biomass calculated at 5057 tww in the 2005–2006 and 10 213 tww in the 2006–2007 seasons. A sequence of phases showing differing appearance, biomass growth and tissue nutrient changes were identified and documented. The role of nutrients (individually and collectively) in the enhancement of L. majuscula growth (Research Question 2) was investigated using a combination of comprehensive laboratory experiments (filament growth, 14C-bicarbonate uptake rate and biomass increase) and in-situ field experiments. Addition of nutrients to the water column were shown to promote prolific L. majuscula growth in the laboratory; this was confirmed in field experiments at two locations in Moreton Bay—showing nutrients can be a major causal factor in bloom formation. Additions of phosphorus (macronutrient) and iron (required for photosynthesis and nitrogen-fixation) caused the greatest stimulation of L. majuscula in both laboratory and field experiments. The form of iron was shown to be important —organically complexed iron (FeEDTA) was substantially more effective in promoting L. majuscula growth under laboratory conditions than inorganic iron (FeCl3). This is important as FeEDTA mirrors the naturally occurring iron organic complexes (which increase the solubility of iron) in waters from the region. The effect of nitrogen additions was more complex—likely due to the capacity of L. majuscula to fix atmospheric nitrogen reducing reliance on an inorganic nitrogen source. In the high light conditions experienced in this study, L. majuscula appeared to acquire nitrogen: (i) directly from the dissolved inorganic nitrogen in the water column—evidenced by a positive response to the nitrogen treatments; and, (ii) through enhanced nitrogen-fixation rates when iron and/or phosphorus were added in the absence of nitrogen—inferred from a substantial increase in the total nitrogen content of the L. majuscula biomass (nitrogen-fixation was not measured directly). The main sources of naturally occurring nutrients likely to promote L. majuscula blooms in Moreton Bay (Research Question 3) were investigated using laboratory experiments, soil and water analyses, and GIS-based modelling. The potential for groundwater/surfacewater from different vegetation, soils, geology and landuses within the study area catchments to stimulate L. majuscula response (14C-bicarbonate uptake rate) was tested in laboratory bioassays. Areas with acid sulfate soils (ASS), Melaleuca vegetation, pine plantations and Casuarina on ASS all had waters that enhanced L. majuscula growth. To investigate causal agents, bioassay response data and water analyses were subject to multiple regression and correlation analysis; this confirmed the importance of iron, phosphorus and nitrogen to L. majuscula growth and the roles of low pH and dissolved organic carbon, the latter two appearing to influence the chemical state and enhance the solubility of nutrients to L. majuscula. This information was incorporated into a GIS-based model to identify areas of hazard which were most likely to supply/export nutrients to Moreton Bay. These hazard maps, with further local verification, will be used as planning and decision support tools to assist government and landuse managers to limit the mobilisation and transport of key nutrients to potential bloom sites. The results from this thesis demonstrate that a precautionary approach to limit phosphorus, iron, nitrogen and dissolved organic carbon to waterways is necessary; otherwise the magnitude of L. majuscula blooms is likely to increase in Moreton Bay as coastal development intensifies with the predicted population increase. The thesis findings provide strong support for the hypothesised link between nutrients and the increased proliferation of Lyngbya and other benthic cyanobacteria blooms and are likely to be applicable to other areas where environmental conditions are suitable for their growth.

Blur: Gerhard Richter and the photographic in painting

Hawker, Rosemary — 2008-11-21T00:00:00Z

Bodily Integrity and Disability in Roman Literature and Rhetoric: The Case of Emperors, Children and Military Leaders

Helen Tanner — 2012-03-12T00:00:00Z

Historians of the ancient past, almost without exception, have approached the topic of disability by identifying pathological conditions within the available evidence to gauge perceptions or cultural responses. By framing disability in this way, scholarship in this field has often relied on an implicitly understood medical distinction between bodily ‘normality’ and ‘abnormality.’ Scholars in the emerging field of disability studies have criticised this ‘medical model’ approach for wrongly assuming that such a distinction is objective and enduring, and thus unchanging between cultures and over time. Among scholars of disability, a strong consensus has emerged, proposing instead that physical normality and abnormality is more accurately understood as a socially negotiated distinction based on capacity to perform expected social roles in the community or society. While this ‘social model’ of disability has come to be accepted in other strands of historical inquiry, historians concerned with ancient disability have largely ignored the work of disability studies scholars. This thesis applies this modern theoretical approach to the ancient literary evidence and demonstrates how such a reading enhances our understanding of Roman attitudes towards disability. In light of the preference held by previous scholars to focus upon Greek history and evidence, this thesis has also sought to move the focus more firmly into the Roman period. By examining the bodily capacity of emperors,the rejection of children on the basis of bodily abnormality, and depictions of wounds and wounding among military leaders, this thesis consistently demonstrates that perceptions of bodily normality and abnormality were measured against and determined by considerations of an individual’s capacity to perform socially and culturally determined roles. Although this study is by no means a comprehensive analysis of disability in the Roman world, it nevertheless demonstrates support for a social model approach to disability in this context. This thesis also represents a further step in the liberation of this topic from its isolated position in the modern corpus of historical scholarship, and the forging of a mutually beneficial association between scholars of ancient history and scholars of disability.

Body Composition Measurements and Nutritional Status in Children with Clinical Conditions: Cystic Fibrosis and Cancer

Murphy, Alexia — 2010-11-11T00:00:00Z

Abstract Malnutrition, as indicated by body composition measurements, is a common problem in many paediatric diseases and is an issue of considerable concern. Optimal body composition is vital in children with clinical conditions because body composition will ultimately affect prognosis. In order to manage nutritional problems, it needs to be understood what body composition changes occur in children in response to clinical conditions and how body composition can be validly measured in paediatric clinical populations. This thesis investigated the body composition of children between five and 18 years of age from three different populations; healthy, diagnosed with cystic fibrosis or diagnosed with cancer. This research aimed to formulate the Body Cell Mass Index for use in children, report on the suitability of body composition methods for use in paediatric cystic fibrosis and cancer populations and detail the body composition of children with cystic fibrosis and cancer. This research showed that the Body Cell Mass Index for interpreting total body potassium measurements in children is BCM/HT2.5 for females and BCM/HT3 for males. Section Two on the validity of body composition assessment methods found that air displacement plethysmography can be used in cystic fibrosis populations to determine body composition, but that currently available bioelectrical impedance analysis equations should not be used to determine fat free mass in children with cystic fibrosis. In the cancer population, it was found that the recommended methods of weight and height indices, arm anthropometry and albumin measurements do not accurately determine nutritional status. Section three of the thesis examined the nutritional status of children with cystic fibrosis and cancer. It was found that while the children with cystic fibrosis were well nourished despite their condition, that children being treated for cancer were malnourished with low levels of body cell mass and high levels of fat mass. The determination of the Body Cell Mass Index in this thesis has changed and improved the way body cell mass results are reported for children assessed in the Body Composition Laboratory, Royal Children’s Hospital. The methodology findings will lead to better identification of nutritional problems in children with cystic fibrosis and cancer, with clinical centres adopting appropriate body composition techniques in these populations. The reporting of the nutritional status of children with cystic fibrosis and cancer will ensure that clinicians understand the impact that these conditions have on nutritional status and will allow them to tailor nutritional interventions to combat the potential changes that may result in each condition.

Body heat in the dairy cow

Hall, Anita Bernice. — 2010-10-13T00:00:00Z

Boltzmann machine learning : analysis and improvements

Wood, Ian Andrew. — 2007-08-24T00:00:00Z

Bone strength parameters in children and adolescents with cystic fibrosis: examining the muscle-bone unit

Brookes, Denise Susanne Kaesler — 2013-01-11T14:05:15Z

Border Gods in Communities and Classrooms: Toward a Pedagogy of Enchantment

Dale Allender — 2010-03-03T00:00:00Z

Mythology is a consistent part of the high school English language arts school curriculum dating back well beyond the last forty years. High school English teachers‘ beliefs about mythology, student engagement, and educational policy demonstrate the rationale and dynamic of this longevity. This study explores the development and elements of myth, asserting the importance of approaching myth through critical cultural studies generally, and in high school English arts classrooms specifically. Drawing upon a variety of cultural sources (i.e. sacred narrative, children‘s television, cable news television, literature, movies, music, and the internet); theorists (from Levi-Strauss‘s structuralism through the post-structuralism of Barthes, Anzuldua, and Maya Derrin); and methodologies (content analysis of murals, news excerpts, teacher footage on video literary analysis, and autoethnography) this study presents a critical cultural studies exploration of myth and myth studies. After deconstructing and applying Levi-Strauss‘ notion of Bricolage to a wide variety of contexts, I conclude that myth is based in all sorts of individual and collective human movement. And this movement gives rise to myth which can be characterized as political, spiritual inter-textual, performative and hybrid. I further conclude that a critical cultural studies approach to myth attends to student engagement, anticipates 21st century learning frameworks, and offers possible consideration of interfaith education in schools.

Boron nutrition of hass avocado (Persea Americana Mill.)

Smith, Timothy Edward — 2007-08-24T00:00:00Z

Bose-Einstein Condensates In Non-Harmonic Optical Potentials

Sebastian Schnelle — 2011-12-12T00:00:00Z

This thesis presents work on Bose-Einstein condensates in non-harmonic optical potentials. First, a new trap design developed at the University of Queensland is presented that allows the creation of nearly arbitrary two-dimensional potential landscapes by spatially scanning a far red-detuned laser beam using a two-dimensional acousto-optic modulator. In conjunction with a feed-forward technique this trap is capable of producing optical traps which have the necessary stability to be used in ultra-cold atom research. Different geometries are presented. In particular toroidal trap geometries are discussed which are interesting because they offer the possibility for a multiply connected Bose-Einstein condensate. The trap also offers the possibility of dynamic potentials which have been employed to measure the critical velocity of superfluidity in Bose-Einstein condensates. Secondly, measurements on condensation dynamics are presented which use an optical dimple potential superimposed upon a harmonic magnetic trap. In the experiments the dimple potential is ramped on slowly or turned on suddenly for a range of dimple depths and widths and the condensate fraction and temperature are measured as a function of hold times. The measurements taken are compared to equilibrium thermodynamics and quantum kinetic theory and for the first time a quantitative model is presented that allows correct prediction of condensate fractions and temperatures in good agreement with the measurements. Also presented are first results in condensate rethermalization experiments where a dimple potential is suddenly switched off and the condensate left to rethermalize in a much wider magnetic potential. The measurements show a sudden breakdown in condensate fraction followed by a subsequent recovery. So far no theory exists to properly interpret the results as quantum kinetic theory cannot be applied to the problem. Lastly, progress on experiments to measure the critical velocity of superfluidity in Bose-Einstein condensates is reported. Calculations have been carried out that show the creation of solitons and vortices as mechanisms to dissipate energy leading to a breakdown of superfluid behaviour at velocities lower than that predicted by Landau’s theory of superfluidity, the first theory to describe superfluidity. Progress on an experiment is presented that uses the scanning beam trap developed as part of this project to create a line potential with a moving barrier to measure the critical velocity and show solitons and vortices as the mechanisms for energy dissipation as seen in the calculations.

Boundary Layer Separation in Hypersonic Ducted Flows

Andrew Dann — 2009-11-03T00:00:00Z

Experiments to generate multiple shock waves in an axisymmetric model at hypersonic speeds were conducted in a small reflected shock tunnel. Conical surfaces were used to generate shock waves inside a circular duct chosen to be representative of a scramjet combustor. These shock waves impinged on turbulent boundary layers to produce shock wave/boundary layer interactions (SWBLIs). In the process of observing this phenomenon, the commonly used empirical correlations of Korkegi were tested for accuracy, i.e. the combined pressure ratio across these shocks can be measured and compared to that predicted by these correlations. Korkegi correlates only with Mach number, and is independent of Reynolds number and on how the pressure is applied. A major contribution of this work is to examine how the details of the compression process effect separation. In this study, the history of applying the compression was varied. An analytical method was developed for theoretically estimating the onset of incipient separation using an integrated computation of the momentum flux contained in the boundary layer. By including the summed (negative) contribution of wall shear stress on the integrated momentum flux, the upstream history of the boundary layer was considered. The overall result has a form similar to the Korkegi correlations, plus an additional correction term relating to momentum loss through wall shear stress. The correction term was determined to be a second order effect, which explains why the Reynolds number independent Korkegi correlations work so well over such a large range of conditions. A hypersonic flow test condition conducive to the generation of high Reynolds number flows and turbulent boundary layer production was developed in a small reflected shock tunnel. The experimentally measured flow parameters were matched by numerical simulation using a number of in-house codes at The University of Queensland. This has allowed the unmeasured parameters which are numerically derived to be stated with greater confidence. An internal centre-body with a conical forebody was used to generate conditions of incipient separation. This provided benchmark data for comparison with subsequent experiments with multiple compressions. A semi-vertex angle of 15o was selected based on Large Eddy Simulation (LES) numerical results once the experimental and numerical static wall pressure and heat flux were matched. A two-cone experimental model, which provided for adjustment of the axial separation between the two shock systems, was tested at the same flow conditions as used in the single-cone experiments. A technique of incrementally moving the instrumentation (relative to the centre-body) and repeating the same condition to achieve high resolution in pressure and heat flux distributions with a limited number of transducers was successful. The results verified that it was possible to subject a hypersonic turbulent boundary layer to two quantified compression-expansion systems with an adjustable axial separation between them and capture the first reflected shock in a “shock trap” to remove it's influence from the second SWBLI. The data from this initial two-cone model provided non-separated pressure and heat flux data which was used as a reference to help interpret data from separated flows. The commercially available Reynolds Averaged Navier-Stokes (RANS) numerical code, CFD-Fastran, was used to help design an experimental model which produces boundary layer separation. Algebraic and two-equation turbulence models were applied to a modified two-cone model to show greater pressure rises which would produce boundary layer separation. A modified two-cone model was tested and demonstrated boundary layer separation. Three configurations with varying axial separation between SWBLIs were tested which all produced separation. The configuration that produced the largest pressure ratio and largest separation region at the second SWBLI may represent a geometry whereby the distance from the hollow cylinder inlet and the second cone may represent a critical value. The amount of viscous interaction, generated from the leading edge of the shock trap, and the proximity of the two interactions may be coupled to produce higher than expected values. It is postulated that the boundary layer momentum recovery for the configuration where the second SWBLI was furthest downstream (30 mm configuration), prevented severe separation from occurring. An in-house RANS code, elmer3, was used to simulate the flow of the modified two-cone model. An algebraic turbulence model was applied to this model and comparisons of experimentally measured static wall pressure and heat flux have given good agreement. The wall shear stress was investigated to provide further information concerning the position and size of flow reversal regions. The use of the numerical codes utilised in this study has reinforced their effectiveness for model design and comparison of experimental results.

Bounds on integrals of the Wigner function

Wood, James Gareth — 2007-08-24T00:00:00Z

Bovine enterovirus: Molecular characterisation and evaluation as a vaccine vector

McCarthy, Fiona — 2008-11-21T00:00:00Z

The purpose of this study is to characterise Australian isolates of bovine enterovirus (BEV) and develop a suitable isolate as a replication-limited vaccine vector. Advantages of using BEV as a vector are that it both elicits mucosal immunity and has naturally occurring temperature stable isolates so that a BEV vector could be administered orally to elicit a protective immune response in the host and should not require cold storage to maintain vaccine efficacy. Furthermore, wildtype BEV causes no or only mild clinical symptoms in its host and if BEV is used as a vaccine vector, reversion to wildtype phenotype would not cause deleterious effects in vaccinated cattle. To date many of the viruses used as vaccine vectors are produced by modifying the structural proteins of the virion so that they contain heterologous sequences. However, each of the four BEV structural proteins are essential and it is not possible to insert large sequences without disrupting the virion. While this study looks at potential insertion sites within the BEV virion, the main focus for the development of BEV as a vaccine vector is through using a replication-limited BEV vector. The development of a replication-limited vector requires the deletion of an essential viral gene that is then replaced in vitro using an expression vector. When the replication-limited vector and its complementing expression cassette are co-transfected into a permissive cell line all the proteins required for viral assembly are produced but only replication deficient genomes are available to be encapsidated. The physically intact but replication deficient viral particles produced in vitro can then infect permissive cells in vivo, resulting in the production of all but the deleted viral protein. Moreover, the deleted portion of the viral genome can be replaced with heterologous sequences within the replication-limited BEV vector. These heterologous sequences can then be expressed in vivo where they can be recognised by the host immune system. Three BEV isolates representing the Australian subserotypes were used in this study: K2577, SL305 and 66/27. The full-length sequences of K2577 and SL305 were obtained as well as partial sequence from the third isolate, 66/27. Sequence homology and phylogenetic analysis showed all three isolates were more closely related to BEV-1 subserotypes than BEV-2. This is the first report to indicate that Australian BEV isolates can be classified as BEV-1. Analysis of the 5-untranslated region (5-UTR) indicated that BEV isolates were recombinants with each other and that these recombinant regions correspond to the duplicated cloverleaf structure which is present in BEV 5-UTR but absent from other enteroviruses. While BEV was initially reported to be stable at higher temperatures, later studies showed that this property varied between isolates and this is also true of the three isolates used in this study. Since it is important not only to ensure that the isolate used as a vaccine vector is temperature stable but also the resulting vaccine vector, the molecular basis of BEV temperature stability was also studied. Using sequence data from the Australian isolates, regions of variation were located and hybrid BEV created. Unfortunately, all of the hybrid BEV produced in this study were non-infectious and could not be used to for further characterisation of BEV temperature stability. Preparatory to constructing replication-limited BEV, a system for full-length amplification of BEV was developed. By including sequences for the bacterial promoter T7 on the positive sense primer used for full-length amplification of BEV, it was possible to prepare full-length transcripts of the amplified product and these were shown to produce infectious BEV particles when transfected into to cell lines that supported BEV growth. Subsequent cloning of the K2577 amplification product resulted in infectious clones for this BEV isolate and these clones were used to prepare replication-limited BEV constructs. To test the replication-limited system BEV structural genes were replaced with a reporter gene to produce replication deficient infectious clones. Complementary constructs containing only the deleted structural genes were also prepared to express the deleted genes. While it was expected that these expression vector would be able to complement the replication deficient BEV in vivo, co-transfection of the replication-limited construct with its complementing expression vector did not produce viable BEV.

Bovine immune responses to cattle tick infestation

Emily Piper — 2010-08-15T00:00:00Z

The cattle tick, Rhipicephalus Boophilus microplus (formerly Boophilus microplus), is the most significant parasite of cattle in Australia and threatens the improvement of cattle production in tropical and subtropical countries worldwide. Some cattle breeds of mainly Bos indicus origin develop a strong resistance to infestation with R. B. microplus, while other breeds of mainly Bos taurus origin will succumb to anaemia and ‘tick worry’ in tick-infested pastures. Resistance to cattle tick infestation is primarily manifest against the larval stage and results in the immature tick failing to make a successful attachment and obtain a meal. It is widely accepted that resistance to tick infestation in cattle is immunologically mediated and involves both cell-mediated and humoral immune responses. Previous research has demonstrated a role for the hypersensitivity response in the rejection of larvae from resistant B. taurus cattle. The immune response to R. B. microplus infestation in B. indicus and B. indicus × B. taurus cattle has not been studied in great detail and this thesis aimed to describe those responses of highly tick-resistant cattle that differ from those of tick-susceptible cattle. A pilot trial was conducted using six tick-resistant Brahman heifers (B. indicus) and six tick-susceptible Holstein-Friesian heifers (B. taurus). The animals were artificially infested for several weeks and blood samples obtained weekly for three weeks during the height of infestation, and on one occasion, skin biopsies obtained. It was found that significant differences existed between the two breeds with respect to the percentage of cellular subsets comprising the peripheral blood mononuclear cell (PBMC) population, cytokine expression by peripheral blood leukocytes (PBL), and levels of tick-specific immunoglobulin G1 (IgG1) antibodies measured in the peripheral circulation. These results in combination with whole genome expression analysis of circulating PBL suggested that the B. indicus cattle had developed a stabilised T cell-mediated response to tick infestation evidenced by their cellular profile and leukocyte cytokine spectrum. The B. taurus cattle demonstrated cellular and gene expression profiles consistent with a sustained innate, inflammatory response to infestation, although high tick-specific IgG1 levels suggested that these animals had also developed a T cell response to infestation. Gene expression analyses using quantitative PCR (qPCR) and whole genome expression platforms indicated that the B. taurus cattle elicited an innate inflammatory response in the skin at the site of larval attachment. This was supported by histological examination of the tick-attachment sites. Conversely, the B. indicus cattle appeared to limit the inflammatory response and instead exhibited increased expression of genes involved in wound healing and the structural integrity of the skin. A second trial was conducted using a group of tick-naïve Santa-Gertrudis heifers to eliminate any innate breed differences that may have confounded the results obtained in the pilot trial. Thirty-five animals were obtained from a tick-free region of Australia; thirty animals were artificially infested weekly for thirteen weeks while five animals remained at a tick-free quarantine property to serve as a control group. Following thirteen weeks of tick infestation the animals in this trial exhibited divergent tick-resistance phenotypes and those carrying the lowest and highest numbers of ticks were classified into tick-resistant (n = 6 animals) and tick-susceptible (n = 6 animals) groups, respectively. The larger number of animals in this study and repeated measurements over the course of the trial enabled a detailed analysis of the effect of tick infestation across all animals, and also within the groups identified as highly resistant or highly susceptible. A cell-mediated response to tick-infestation was detected in all tick-infested animals by twenty-one days after the initial infestation, a response which waned towards the end of the trial when the antibody response became more dominant. Similar to the pilot trial, the tick-susceptible animals developed significantly higher levels of tick-specific IgG1 antibodies compared with the tick-resistant group. Some differences were observed between tick-resistant and tick-susceptible animals with respect to the percentage of cellular subsets comprising the PBMC population. Skin biopsies were taken from these animals prior to initial infestation and then at twenty-one days and ninety-one days after the initial infestation and whole genome expression profiles were produced and analysed. At twenty-one days post infestation both tick-resistant and tick-susceptible animals demonstrated an upregulation of genes involved in leukocyte migration and complement activation, suggestive of an inflammatory response. While this response persisted in the tick-susceptible group at ninety-one days post-infestation, it appeared to lessen in the tick-resistant group. A dominant interleukin-8 (IL-8) response was observed in the skin of the tick-susceptible animals at both time points post-infestation that was not observed in the tick-resistant animals. This thesis demonstrates that tick-susceptible animals respond to infestation with R. B. microplus with an apparently non-protective antibody response, and that tick-resistant animals demonstrate different structural responses in the skin at the tick-attachment site compared with the intense inflammatory response observed in tick-susceptible animals. The results presented here suggest that the extreme susceptibility of pure B. taurus and some B. taurus × B. indicus individuals may be due to their heightened ability to recognise and respond to tick antigens introduced into the host via tick saliva during the blood feeding process. These animals’ increased ability to recognise and respond to these proteins may act to set up a chronic state of inflammation that is beneficial to the tick through increased capillary permeability providing a suitable environment for tick feeding and survival.

Boys, masculinity and reading: Exploring differences amongst male readers.

Laura Scholes — 2011-08-24T00:00:00Z

The purpose of this study was to explore how students interpreted their experiences reading with the aim of developing an empirically justified account of the apparent systematic underperformance of boys, compared to girls, on national and international reading benchmarks. Exploring the diverse nature of students’ interpretations of their reading experiences, this study moved beyond broad generalizations about boys and girls to consider complexities inherent in notions of masculinity and associated tensions. Specifically, this study examined and further developed understandings about the ways in which notions of masculinity were constructed among different groups of boys in school contexts and the influence of these differences on educational experiences, such as reading. From an understanding of literacy as sociocultural practice, reading was considered a concept defined by social and communication practices students engaged in their everyday lives. Implementing a mixed method approach this study involved a survey and follow up semi-structured interviews. Initially, a paper and pencil survey collected information from 297 students attending year 4 and year 5 in seven primary school contexts. The survey asked boys and girls about their attitudes, beliefs and enjoyment of a range of activities including reading. Additional information was also collected concerning each student’s reading level, reading frequency and the socioeconomic status of the participants’ school community. Analysis of the survey data identified six clusters of students who presented in a similar manner. Thirty-four students from six clusters then took part in follow up semi-structured interviews to substantiate and further develop survey findings. Findings were considered within a broad ecological framework. This conceptual framework provided a lens for developing understandings about the multiplicity and interconnected nature of contextual influences on boys’ experiences as readers. The study found that while more girls than boys indicated high reading achievement, high reading frequency and high levels of reading enjoyment, these differences were not as prominent as expected. For example, while there was a male majority in the lower achieving anti-reading cluster, which portrayed reading as “uncool” and “nerdy” this group made up only thirteen percent of the total male cohort. Significantly, boys were also well represented in the higher achieving, avidly reading groups. There were, however, noteworthy differences in attitudes toward the social aspects of reading, with some boys indicating significantly negative attitudes and some girls reporting considerably higher levels of enjoyment. Findings also indicated that some expressions of masculinity were interpreted as problematic for many boys in personal and potent ways, constraining their social experiences as readers. Furthermore, disadvantage was found to be a significant factor with some but not all students. That is, disadvantage was interpreted as an interactional influence compounding constraining reading experiences for some boys. Findings build upon and extend understandings about the role of masculinity in creating and constraining reading experiences for boys in school spaces. Interpretations indicated inflections in boys’ experiences as readers highlighting diversity and the need to make visible differences amongst boys. It is argued that the systematic underperformance of some boys, compared to some girls, is influenced by particular attitudes and actions that boys internalise through their everyday social interactions and it is these interactions that contribute enabling and constraining influences on reading attitudes, reading frequency and subsequently performance. Furthermore, findings indicated the need to facilitate educational policies and practices that consider broader social processes with recognition for “which boys” and “which girls” are underachieving in reading.

Bradman : representation, meaning and Australian culture

Hutchins, Brett. — 2007-08-24T00:00:00Z

Brain Development and Behaviour in Developmentally Vitamin D-Deficient Mice

Lauren Harms — 2012-01-06T00:00:00Z

Schizophrenia is a debilitating neuropsychiatric disorder associated with a wide range of genetic and environmental risk factors. Based on epidemiological evidence, maternal vitamin D deficiency has been proposed as an environmental risk factor for schizophrenia. Recent findings showed that low levels of vitamin D at birth were associated with an approximate two-fold increase in the risk of developing schizophrenia in later life (McGrath et al., 2010). Moreover, a rat model of developmental vitamin D (DVD) deficiency exhibited neuroanatomical and behavioural phenotypes analogous to schizophrenia (Eyles et al., 2009b), further supporting the biological plausibility of the epidemiological link between DVD deficiency and schizophrenia. Studies in a mouse model of DVD deficiency revealed that brain development and adult behaviour were affected by DVD deficiency in a strain-dependent manner (Harms et al., 2008; de Abreu et al., 2010). To further explore the effects of DVD deficiency on the mouse brain and to facilitate potential future genetic studies into DVD deficiency, the aim of the current thesis was to examine the effects of DVD deficiency in mice by assessing gene expression, cell proliferation and brain morphology in neonatal mice, as well as comprehensively assessing behaviour and brain morphology in DVD- deficient adult mice. DVD deficiency in C57BL/6J mice resulted in early changes in forebrain gene expression. Compared to brains from control mice, some 700 genes were differentially expressed in the brains of DVD-deficient neonates, the vast majority of which were down regulated. Pathways analysis of the genes that were down regulated revealed that the reelin and neuregulin signalling pathways were altered. Both of these pathways play an important role in brain development and have been implicated in schizophrenia. These changes in gene expression were not associated with alterations in the proportion of proliferating cells in DVD-deficient whole forebrain samples. However, there were changes in neonatal brain morphology, such that C57BL/6J female DVD-deficient neonatal mice had a smaller hippocampus compared to female controls. Adult C57BL/6J male DVD-deficient mice had smaller lateral ventricles compared to controls, which may have been compressed by the enlarged striatum seen in these DVD-deficient mice. The behaviour of adult DVD-deficient mice was examined in multiple tests used to model the positive, negative and cognitive symptoms of schizophrenia. Compared to controls, C57BL/6J DVD- deficient mice were hyper-explorative of novel stimuli in the hole-board test. Furthermore, male C57BL/6J DVD-deficient mice had altered patterns of locomotion in a test of pseudo-home cage activity; exhibiting lower activity levels at certain times of the day. Male DVD-deficient mice also made more perseverative responses in a continuous performance test of attention, potentially indicating compulsive behaviour and impaired response inhibition in these mice. The combined results from the studies in this thesis demonstrate that DVD deficiency in the mouse was associated with specific neurodevelopmental and behavioural changes. The alterations in gene expression in the reelin and neuregulin pathways in developing mice may suggest a possible mechanism by which DVD deficiency affects the risk of developing schizophrenia in human populations. The behavioural studies indicate that DVD deficiency affects systems involved in novelty-seeking and compulsive behaviours and also affects dopamine-related behaviour in a strain- dependent manner. Ultimately, these results highlight the importance of vitamin D signalling in the developing mammalian brain and present the DVD-deficient mouse as a platform for further investigation of vitamin D, neurodevelopment and schizophrenia.

Brain mapping of acupuncture effects using functional magnetic resonance imaging

Strudwick, Mark — 2009-05-29T00:00:00Z

There remains a high degree of scepticism about acupuncture since its theoretical basis has no clear reference in Western medical and scientific terms, making any associations between neurophysiology and specific acupuncture concepts difficult to determine. Using neuroimaging and engineering approaches to understand its physiological basis may engender greater acceptance of and improvement in the clinical application of acupuncture. Research into the efficacy of acupuncture has raised a number of difficult methodological issues, particularly in relation to the selection of appropriate controls. Separating specific effects from non-specific effects is complex because acupuncture is a physical, invasive, manual procedure involving time and ritual. Sham acupuncture results show only the difference between sham and real acupuncture not the real affect of acupuncture, and other controls may produce distinct subjective and objective effects. Point injection (the injection of a small amount of a substance at an acupoint), a recent innovation of traditional acupuncture, aims to enhance and prolong the stimulation effect in a standardised, reproducible manner. By providing precise, measurable acupoint stimulation applied incrementally in a specifically designed paradigm, an acupoint could act as its own control. This firstly requires injection to be validated against traditional needling. Aims 1. To develop an instrument for reproducible saline delivery at an acupoint. 2. To cross-validate saline acupoint injection (PI) with traditional needle acupuncture (TA). 3. To demonstrate central nervous system (CNS) effects of acupuncture both in health and chronic pain. Hypothesis The primary hypothesis is that stimulation of specific acupoints with linearly incremental saline injection produces differential effects within the CNS observable with functional magnetic resonance imaging (fMRI) allowing investigation of acupuncture in health and chronic pain. Novelty As neuroimaging has not yet clearly defined the brain structures that may be modulated by acupuncture, this project is exploratory in nature. It is expected that acupuncture effects can be robustly imaged with fMRI in healthy subjects and those suffering chronic pain. The demonstrated effects will result from the acupuncture process of progressive point stimulation by tissue distension rather than needle insertion or biological noise. It is proposed to examine the putative modulation of pain by acupuncture within the extensively mapped neuromatrix of cortical and subcortical regions, including the somatic, insula, and limbic cortices, and thalamus. Detailed information regarding differences in brain response between acupuncture in normal and diseased states will expand understanding of acupuncture as a clinical tool. The dilemma of sham stimulation or arbitrary controls will be addressed by confirming PI as a valid, reproducible stimulation method. Methods and Results A series of empirical experiments was designed and conducted to determine the effects of stimulation of different acupoints. 1. Chapters 1 and 3 outline the current understanding of acupuncture in the Western milieu and a review of the neuroimaging literature respectively. 2. In Chapter 2, the report of PI tested against TA in healthy volunteers to determine equivalence of physiological effect demonstrates no statistically significant differences between the methodologies. 3. Chapter 4 reports the design and validation of a task specific microprocessor controlled syringe driver. 4. Four differing acupoints were tested during an fMRI experiment described in Chapter 5; different activation areas were demonstrated across the acupoints providing early support for the hypothesis that different acupoints may have different effects. A subset of brain areas recognised within the pain neuromatrix was delineated, congruent spatially and directionally with those reported in pharmacological analgesia studies. 5. As outlined in Chapter 6, heart rate variability can be measured rapidly in a stressful environment to provide meaningful data on the response of the autonomic nervous system to acupuncture stimulation. 6. The hypothesis of different acupoints having different effects was tested in subjects suffering chronic pain by contrasting an accepted and a neutral acupoint, the results being reported in Chapter 7. Conclusion Despite a long history of clinical usage, appropriate scientific studies have not yet addressed the basic effectiveness and efficacy of acupuncture. This thesis presents a series of empirical studies designed to address a number of the questions arising in the literature and provides converging evidence of the manner in which different acupoints modulate the CNS, specifically within the pain neuromatrix.

Branching in Pea: Molecular Physiology and Computational Analysis

Elizabeth Dun — 2008-03-31T00:00:00Z

BRCA1 interactors and cancer

Felicity A Lose — 2008-05-29T00:00:00Z

BRCA1, Kap1 and the DNA Damage Response

Kienan Savage — 2010-01-29T00:00:00Z

Cancer cells exhibit genomic instability and are commonly defective in DNA damage signalling and/or DNA repair. There are many types of DNA damage inducing agents such as mechanical stress on chromosomes during recombination, chemotherapeutics, ionising and ultraviolet radiation and endogenously produced free radicals. These genetic lesions pose a serious threat to the cell and evoke a rapid and intricate DNA damage response signalling pathway involving many transducer and effector pathways including cell cycle arrest, DNA repair, chromatin remodelling, and apoptotic pathways. Genetic mutations within genes in this pathway often lead to genomic instability and cancer. The main effectors of the DNA damage response are the protein kinases ATM and ATR which are rapidly activated in response to DNA damage induction and phosphorylate a large and diverse number of targets including the checkpoint kinases Chk1, and Chk2, the tumour suppressors p53 and BRCA1 and chromatin associated proteins such as H2AX. BRCA1 is a key transducer molecule within the DNA damage response. This is evident from its loss, which leads to defects in many damage response processes such as cell cycle arrest and DNA repair. BRCA1s binding partner BARD1 has also been implicated in the DNA damage response and recent reports indicate that these proteins co-operate in this pathway. This study utilises a multifaceted approach to further characterise the function of the BRCA1/BARD1 complex within the DNA damage response. Firstly we have used shRNA to deplete the BRCA1/BARD1 complex and have shown that the BRCA1/BARD1 complex is required for ATM/ATR dependent phosphorylation of p53Ser-15 in response to IR and UV induced DNA damage. In contrast, we have shown that the phosphorylation of a number of other ATM/ATR dependent targets including H2AX, Chk2, and c-jun do not require the BRCA1/BARD1 complex. The study has also revealed that the prior phosphorylation of BRCA1 at Ser-1423 and Ser-1524 is required for the phosphorylation of p53 at Ser-15. Furthermore, we have shown that these phosphorylation events are required for IR induced G1/S cell cycle arrest via transcriptional induction of the cyclin dependent kinase inhibitor p21. The second part of this study involved the characterisation of a putative BRCA1 interacting protein – The KRAB associated protein 1 (Kap1). During this study we have been unable to confirm Kap1 as a bona fide BRCA1 interactor, however we have identified a clear role for Kap1 in the DNA damage response pathway. Using Mass spectrometric phospho amino acid mapping we have identified a novel Chk2 dependent phosphorylation site, Ser-473, within Kap1. Furthermore, we have shown that this phosphorylation event may regulate Histone H3-Lys-9 acetylation after DNA damage possibly regulating chromatin relaxation. This study has also identified a number of novel Kap1 interacting proteins, which appear to be regulated by Kap1 phosphorylation at Ser-473. These interactors may play an important role in the regulation of chromatin modification and/or structure after DNA damage. By studying the role of BRCA1 in the DNA damage response pathway we have not only uncovered a novel scaffolding function for BRCA1 in the G1/S checkpoint but have also identified a novel protein, Kap1, acting within the DNA damage response pathway. This study has identified a role for Kap-1 in the regulation of chromatin structure in response to DNA damage via the ATM – Chk2 pathway.

Breaking the Circle of Blame Achieving best practice ecological performance on medium to large scale mixed use precinct developments.

Richard Moore — 2010-07-31T00:00:00Z

Breeding biology of two Parakeelya (Australian Calandrinia) species

Wickramasinghe, Priyanka — 2011-11-14T00:00:00Z

The ornamental horticulture industry is largely driven by the development and commercialisation of novel plant varieties. Australia has an abundance of native plant species with potential for development as flowering ornamentals, but only a small proportion have actually been cultivated and domesticated. To a large extent, this is due to the effort and cost of domesticating new species, and progress is often impeded by a lack of knowledge of the reproductive and breeding biology. Parakeelya sp. (Mt Clere) and Parakeelya balonensis (Australian Calandrinia; family Montiaceae, formerly in Portulacaceae) are floriferous Australian herbaceous succulents with ornamental potential. To facilitate future breeding and development of a range of new ornamental cultivars from these species, and assess their potential for use in intergeneric breeding with distantly related ornamental Portulaca species (Portulaca grandiflora and Portulaca umbraticola) the objectives of this study were to: (1) understand the cytological and phylogenetic relationships of these four species; (2) characterise their reproductive biology and intergeneric breeding compatibility; (3) establish methods for intergeneric hybridization; and (4) assess their amenably to advanced breeding methods such as somatic polyploidization. Infrageneric and intergeneric phylogenetic relationships of Parakeelya were studied using rDNA ITS sequence data of 37 taxa and chromosome number data of 20 taxa. This is the first comprehensive molecular phylogenetic analysis of Parakeelya, with new rDNA ITS sequence data generated for 13 species and seven accessions, new somatic chromosome counts for 13 species and two accessions, and reconfirmed somatic chromosome counts for three species. There were two infrageneric groups of seven of the eight Parakeelya accessions coincident with somatic chromosomes 2n=18 and 2n=24. The species relationships of Parakeelya schistorhiza (2n=36) could not be clearly clarified using rDNA ITS sequence data and chromosome numbers. All 12 Portulaca accessions studied were monophyletic and clustered mostly according to their morphological taxonomy representing subgenera Portullacella and Portulaca. The nine accessions studied in subgenus Portulaca formed three subclades viz. Oleracea, Pilosa and Umbraticola. Portulaca intraterranea was clustered with Portulaca oleraceae in the subclade Oleracea. The study also found that Portulaca oleracea is genetically diverse with three different ITS sequences. The reproductive biology and breeding compatibility of Parakeelya sp. (Mt Clere), Parakeelya balonensis and two popular garden ornamental Portulaca species (Portulaca grandiflora and Portulaca umbraticola) were studied. This work clearly showed that prefertilization intergeneric breeding incompatibility exists for reciprocal crosses of Portulaca grandiflora  Parakeelya balonensis (2n=18) and Portulaca umbraticola  Parakeelya sp. (Mt Clere) (2n=24). Further, the study found breeding compatibility of intraspecific outcrosses of all four species, partial self-compatibility of Parakeelya sp. (Mt Clere) and Portulaca grandiflora, self-incompatibility of Parakeelya balonensis and Portulaca umbraticola and autogamy of Portulaca grandiflora. To assist future research efforts to overcome these prefertilization breeding barriers using in vitro ovule pollination and embryo rescue, studies were performed to characterize capsule and seed development, and to establish in ovulo embryo culture of intraspecific control crosses and in vitro ovule culture of these four species. The study demonstrated that in ovulo embryo culture is possible for Portulaca umbraticola. Since breeding incompatibility hindered intergeneric hybridization, the efficacy of somatic polyploidization was investigated as a tool to accelerate the domestication of Parakeelya sp. (Mt Clere). For the first time, the study generated fertile colchicine induced tetraploids (2n=48) of Parakeelya sp. (Mt Clere) with novel flower characteristics of ruffled/serrated petal edges and darker red, and wider red and white petal sectors. Stomata density, guard cell length, anther length and flower bud diameter were efficient tools for discerning diploids and tetraploids. However, breeding incompatibility existed between colchicine induced tetraploids and diploids of Parakeelya sp. (Mt Clere), hindering the production of triploid plants. This thesis provides the first reports of the phylogenetic relationships, cytology, reproductive biology, breeding compatibility and polyploidization of Parakeelya sp. (Mt Clere) and Parakeelya balonensis and optimized protocols for future breeding research in these key areas. Hence, it has generated significant and essential new knowledge required for the development of more efficient breeding programmes for the early domestication of Parakeelya sp. (Mt Clere) and Parakeelya balonensis for ornamental horticulture.

Breeding psyllid resistant Leucaena varieties using interspecific hybrids between Leucaena leucocephala (Lam.) de Wit ssp. glabrata (Rose) S. Zárate and L. pallida (Britton & Rose)

Gerardo Solis-Pasos — 2007-08-24T00:00:00Z

BRING THE BOMBS OUT OF THE BASEMENT: THE UNITED STATES, THE NPT,AND THE NUCLEAR NON-SIGNATORIES, 1961-1974

Eliza Matthews — 2010-03-12T00:00:00Z

ABSTRACT Since the dawn of the atomic age, the United States of America [US] saw the problem of nuclear proliferation as one of its own creation and therefore theirs to rectify. Perhaps motivated by a form of nuclear imperialism, the US held the majority of the aspiration and ability to solve the international problem of nuclear proliferation. In hindsight there is perhaps very little that successive presidential administrations could have done to prevent the spread of nuclear weapons during this period without significantly affecting their own international ambitions. However, the possibility that the US could have obtained the signatures of the nuclear non-signatories of India, Pakistan and Israel on the Treaty on the Non-Proliferation of Nuclear Weapons (1968) [NPT] became more remote due to the determination of those states to act independently and demonstrate their authority over their own nuclear matters in the shadow of both the superpowers during the Cold War. Furthermore, the American failure to obtain early agreement on the nuclear issue meant that the long-term nuclear ambitions of these nations could not be reversed. Exploiting an array of archival sources, Bring the Bombs out of the Basement analyses the process by which the US sought to bring these non-compliant states into the nuclear non-proliferation regime. It also discusses the significance of the failure of the US to bring the nuclear non-signatories into the fold. Studying the problem under the framework of the NPT as the cornerstone of the nuclear non-proliferation system, it focuses on the period between 1961 and 1974 – from the intensification of NPT negotiations under President John F. Kennedy, to the year in which India detonated its first nuclear device. By analysing the diplomatic interactions between the US and India, Pakistan and Israel, this thesis examines why the US was unable to politically tame one of the most significant scientific research achievements of all time and wield influence in the nuclear arena commensurate to its superpower status. In terms of uniqueness, this is the first study to have comprehensively examined and compared US nuclear policy towards only the nuclear non-signatories.

Broadcasters' Rights: Competing Rationales in the Global Digital Age

Ms Megumi Ogawa — 2008-12-24T00:00:00Z

This thesis clarifies the rationale for the protection of the rights of broadcasting organisations and attempts to provide a theoretical basis for reforming the current regime. This research explores the formation and contents of legislation for protecting the rights of broadcasting organisations and analyses the current issues by means of a comparative study of Australian and Japanese law. The thesis starts with an introduction setting out the parameters of the argument, examination of previous research in relation to the topic, explanation of two approaches to the protection of broadcasters’ rights, the hypothesis, the scope, the material covered and the structure of the thesis. It then provides a detailed explanation of the key concepts (broadcasting, broadcasting organisation and the rights of broadcasting organisations). The research analyses the legal context in which those concepts operate in order to establish the scope of the legal inquiry into the rights of broadcasting organisations. The thesis then examines the international conventions and transnational legislation regarding protection of the rights of broadcasting organisations in order to provide a complete picture of the current situation at the international level. Following analysis of the present situation, the thesis examines the new communication technologies and critically reviews the ongoing discussions for the reform of the current international protection of the rights of broadcasting organisations by the Standing Committee on Copyright and Related Rights in the World Intellectual Property Organisation. The thesis argues that the problems that broadcasting organisations are currently facing stem from the unsatisfactory understanding of the rationale for the protection of broadcasters’ rights. The thesis further argues from the analysis of the Australian Copyright Act 1968 (Cth) as representative of the common law or copyright approach that the rationale for the protection of broadcasters’ rights are in transition. This view is further advanced by the findings obtained as a result of analysis of the Japanese Copyright Law as representative of the civil law approach. The research reveals that the rationale for protection under Japanese law has long been misconceived. The research concludes that the current difficulties in considering the effective reform of the protection of the rights of broadcasting organisations both at the international and national level arose out of the lack of understanding of the rationale for protection.

Broken by the rain

Cheong, Felix. — 2007-08-24T00:00:00Z

Brominated flame retardants - sources and exposure pathways

Leisa-Maree Leontjew Toms — 2009-05-27T00:00:00Z

Summary Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants. The addition of these chemicals to electrical and electronic equipment, building materials, carpet and textiles reduces flammability and therefore harm and destruction caused by unwanted fire. These chemicals are now internationally ubiquitous in the environment and humans because of their increased usage and physical and chemical properties of persistence and lipophilicity. Although Australian data on both the concentrations and the sources and exposure pathways was limited, a preliminary study of PBDEs in 10 pools of human blood serum revealed that concentrations of PBDEs in Australia were comparatively higher than most countries with the exception of Canada and the USA. The aim of this project was to determine the concentrations of PBDEs in the Australian population and to examine the possible sources and pathways of exposure in humans. Experimental evaluation of PBDE exposure matrices included samples of: sediment (n=46), air (n=19), dust (n=19), surface wipes (n=10) and human milk (157 samples combined into 17 pools, n=10 individual samples); and the general population using human blood serum (10552 samples combined into 169 pools). With accumulating evidence regarding age differences in PBDE concentrations, the scope of this project was broadened to include a focus on infants and young children. This study found that PBDE contamination was widespread in the Australian environment and human population. In sediment, PBDEs were relatively low at the majority of sites with mean ± standard deviation and median ΣPBDE concentrations across all sites of 4707 ± 12580 and 305 pg g-1 dw, respectively. There were elevated concentrations found downstream of sewerage treatment plants; in areas dominated by industrial and urban land-use types; and in estuarine compared to freshwater environments. PBDEs were detected in air, dust and surface wipes. Concentrations on the whole were found to be higher indoors compared to outdoors and in offices compared to homes. ΣPBDE concentrations ranged from 0.5 -179 pg/m3 for homes and 15 - 487 pg/m3 for offices and at the two outdoor sites the concentrations were 1.7 and 6.8 pg/m3. PBDEs were detected on 9 out of 10 surfaces (e.g. television, refrigerator, DVD player) sampled and ranged from non-detectable to 5985 pg/cm2 while in dust, ΣPBDEs ranged from 87 - 733 ng/g dust in homes and 583 - 3070 ng/g dust in offices. PBDEs were detected in all individual and pooled samples of human milk and blood serum and the ΣPBDE and BDE-47 concentrations ranged from 5.5 to 103 and 0.6 to 55 ng/g lipid, respectively. There were no regional differences in concentrations in human milk or blood serum and in general PBDE concentrations were higher in males than in females. Although no temporal trend was apparent in samples of human milk or blood serum collected between 2002 and 2008, the ban on penta- and octa-BDE commercial products in several countries has only been in place since 2004. Hence, effects of the ban may not be reflected in human body burden for several years. The concentrations of PBDEs were found to be highest in young children aged 2 – 5 years of age where concentrations were up to 10 times greater than those detected in adults. Congener profiles for sediment, air, dust and surface wipes were mostly dominated by BDE-209. In human milk and serum, BDE-47 was dominant while BDE-209 contributed only 3% in human milk and was not determined in serum. Concentrations of PBDEs found in Australian human and environmental samples were lower than those reported from North America but higher than those reported from Europe and Asia. The results of modeling and the assessment of matched samples of human milk, indoor air and dust showed that body burden could be partly explained by exposure via food, air, dust and human milk as well as clearance (half-life) data. However, the higher than expected concentrations in young children indicated that there are likely to be missing sources and exposure pathways and/ or the clearance data is inaccurate. The results of this thesis provide baseline data on PBDE concentrations in Australia and will prove important for long term monitoring of the effect of changes in usage rates of these chemicals. It is important to understand the specific sources and exposure pathways of PBDEs in infants and young children in order to identify intervention methods whereby exposure to this vulnerable population can be reduced. In terms of the future use of PBDEs or other flame retardant chemicals, it is important that the risk-benefit ratio is regulated so that the minimization of human exposure and potential associated negative health effects is balanced with the reduction of harm caused by fire.

Bronchoscopy and Airway Disorders in Children

Masters, Ian Brent — 2008-04-03T00:00:00Z

Tracheobronchial structural lesions present a considerable diagnostic challenge and workload to tertiary paediatrics. Bronchoscopy is the definitive way of confirming these diagnoses. Quantification of the size of lesions is important to the decision-making processes for management, yet this aspect of assessment has been left to subjective visual estimates of the size as there has not been a method developed that enabled quantitative measurement. The clinical profiles of children with these disorders have long been suspected to be worse than respiratory illnesses in normal children however this aspect has never been studied using objective criteria. The major hypothesis of this thesis is that structural lesions such as malacia disorders of the tracheobronchial tree result in significant respiratory morbidity that is a result of dose dependent crossectional area losses in lesions which improve with increasing age and management strategies. The aims of this thesis were i. to develop a methodology for objectively quantifing airway lesions using a paediatric bronchoscope ii. establish a cohort of children with airway lesions and quantitatively define the airway lesions and then longitudinally study these lesions and the respiratory illness profiles using validated scales of illness over a 2 year period.

BROWNING MECHANISM IN BACKHOUSIA MYRTIFOLIA

Sarana Sommano — 2011-08-13T00:00:00Z

Backhousia myrtiflolia is an Australian native that has recently been cultivated for cut flowers. Browning in the leaves and flowers (sepals) of this plant has become a hurdle for the export marketability of its cut foliage. Understanding the mechanism and triggers for this discolouration is important for the further development of methods that could ideally prevent browning. This research study focussed on a biochemical approach to understanding the enzymatic browning process. One clear cause of browning in this species is reported herein. Browning in B. myrtifolia potted plant leaves was observed during winter 2008 - 2009. Koch’s postulates were performed with leaf lesion explants. The discolouration proved to be a result of plant disease from a single fungus morphologically identified and confirmed as Alternaria alternata. Inoculations on attached leaves and detached flowers were positive in terms of causing browning. However, not all browning in B. myrtifolia can be attributed to pathogenic infection. The physical and biochemical browning processes of B. myrtifolia were investigated. Browning was elicited by heating the tissues at 60C for 30 and 60 min. Changes in electrolyte leakage (EL), malondialdehyde (MDA) content, polyphenol oxidase (PPO), peroxidase (POD) and phenylalanine ammonialyase (PAL) enzyme activities, total phenolic content and antioxidant capacity (DPPH) were monitored. Leaves were separated into two types, yellow and green, due to observed differences in their browning susceptibility. They were tested for chlorophyll content (Chl a and b) and chlorophyll fluorescence (CF) prior to browning induction. Heat treatment had generally similar effects on physiological and biochemical parameters in both leaf tissue types and also sepals. However, high browning susceptibility in the yellow leaf type was associated with higher post-treatment EL, relatively high initial PPO activity and high pre- and post-treatment PAL activity. The greater initial PPO activity and higher concentrations of reactive oxygen species (ROS) evidently resulted in chlorophyll bleaching in yellow leaves. Light microscopy images of tissues before and after heat-induced browning treatment were compared. The tissues were cleared of chlorophyll pigments using choral hydrate solution. Browning was intensively found in cells surrounding gland structures identified by light and scanning electron microscopy. Browning also appeared on the surface of B. myrtifolia leaves to with B. citriodora essential oil had been applied. This observation suggested an oleocellosis-like phenomenon in B. myrtifolia. Polyphenol oxidase (PPO) and polyphenol peroxidise (POD) are two major enzymes involved in post-harvest browning reactions. Characterisation of these enzymes from B. myrtifolia tissues involved the removal of endogenous phenols by incoperating polyvinyl pyrorolidone (PVPP, an insoluble phenol-absorbing agent) at a concentration of 5% (w/v) in 0.1 M sodium phosphate buffer pH 6.8). PPOs were also activated by the use of Triton X 100 (TTX-100; 2% v/v). POD activity was similary improved by using the same extraction process as for PPO. The protein form the PPO-POD extract (also known as crude extract) was concentrated using an Amicon® filter unit and used for native electrophoresis. The concentrated protein extract lost spectrophotometric activity presumably due to the high amount of phenols and chlorophylls released after detergent was added to the extraction solution. However, strong PPO activity band was detected from this extract with native electrophoresis. Staining of gels for POD activity was not successful. For further purification of the PPO-POD extract, high temperature induce phase partitioning in TTX-114 which eliminated chlorophylls and remaining phenols and thereby improved the enzymatic activity was used. . The enzyme extract partically purified using this optimised extraction combination were characterised for their reaction to pH, their temperature optima, their substrate specificity and their reaction kinetics. The results suggested that PPO and POD from both leaf and floral tissues were of different isozymes as there were peaks in activities in both acidic and basic pH regions. PPO and POD from both tissues types were heat sensitive with temperature optima at 20 - 25°C. Both enzymes were active with mono and diphenol substrates. A kinetic study of these enzymes was made using the partially purified extracts. The enzymatic rate constant (Km) for both PPO and POD suggested that the intercellular substrate concentration was higher in floral tissues than in leaf tissues. It also confirmed that PPO and POD from leaf and floral tissues were different isozymes. The effects of inhibitors of PPO and POD from B. myrtifolia leaf and floral tissues were also investigated. Glutathione was an uncompetitive inhibitor to PPO in leaf and floral tissues at a high concentration of 10 mM. Soduim azide at 0.005 - 0.5 mM was competitive to POD from both leaf and floral tissue types. Enzyme localisation was also examined by using a subcellular extraction method. PPO and POD from both B. myrtifolia leaf and flower tissues were mainly membrane bound enzymes as detected by native electrophorersis (PPO) and Western analysis with specific antibodies (POD). Multiple isoforms were confirmed by 2 dimensional electrophoresis (2 DE) patterns. Overall, browning in B. myrtifolia leaf and floral tissues was a result of cell compartment degeneration which was triggered by stresses (i.e., heat, essential oil toxicity and pathogen). Thereafter, browning related enzymes namely PPO, POD, PAL-phenol reactions were active. Results also suggested that browning was associated with damage to photosynthesis apparatus when plants were grown in the fully-opened area during severe winter condition. Both B. myrtifolia leaf and foral tissues contain a considerable high amount of polyphenol content. This together with high chlorophyll pigments have to be eliminated prior to PPO and POD characterisation study. PPO and POD from leaf and floral tissues are membrane bound proteins and presented in different isozymes as well as different isoforms.

Bubble formation and weeping at a submerged orifice.

McCann, David James. — 2010-09-02T00:00:00Z

Buddhist Meditation Through the Medium of the Internet

Joanne Miller — 2010-01-30T00:00:00Z

Since its inception, the Internet has served as a powerful medium for the dissemination of religious information and the creation of religious communities. Cyberspace now represents an important global paradigm shift in the way religion is conducted. This research provides a sociological account of the affordances the Internet contributes to religious life by examining the ways in which it has influenced the conduct or practices associated with Buddhism. In particular, it assesses the extent to which the rituals constitutive of the Buddhist practice of meditation have been achieved by the Cybersangha, the term Buddhists use for the online Buddhist community. The thesis argues that the Internet is not well suited to the facilitation of particular types of religious understanding and that there are clear limitations to its ability to provide the shared ritualistic experience necessitated by meditation. This is due to the fact that current technology can enable ritual only to a limited degree, and to the ways in which the textual nature of the Internet poses problems for religious experience of an intuitive, non-mediated nature. For these reasons, despite the fact that many websites advertise ‘online meditation’ and despite the strong attempts of some communities to use the Internet as a meditational medium, online meditation cannot be fully facilitated by the Internet. Since a key method by which a Buddhist attains understanding of reality is the use of the body in a meditative act, the inability to provide for embodiment means that the Internet can never offer an experiential equivalent to that of an offline environment. The lack of this experiential aspect means that it cannot in turn provide for holistic, religious communion. As such, there needs to be a further philosophical and practical appraisal of the capabilities of the Internet in general, and as a medium by which a religious experience can be engendered.

Building communities and empowering experiences? Women's voluntary work in Queensland and its place-based dimensions.

Taylor, Barbara Gail. — 2010-05-07T00:00:00Z

Recent international scholarship has placed new emphasis on women’s formative role in the social, economic, political and cultural lives of their respective communities. Some researchers have suggested the greatest legacy of women’s organised contribution to those communities can be found in the history of their voluntary work. Others have urged greater recognition of that contribution through landmark recognition and historic preservation programs. To date, women’s voluntary work in Queensland has drawn limited scholarly interest and it is not well represented on the State Heritage Register. Attempts to establish links between cultural heritage and women’s history generally have been restricted to national heritage agencies in North America and Australia. However, methodologies tended to rely on existing historiography which was traditionally non-inclusive of women, and gaps in the record remained a problem. This thesis seeks to address these developments by undertaking a comprehensive gender-sensitive study of women’s voluntary work and its associated place-based dimensions, across ninety-four groups in Queensland between 1859 and 1959. A central hypothesis asserts women’s formative role as historical agents and community builders, and argues that participation in voluntary work provided opportunities to enrich and empower lives. A social history approach emphasises the diversity of women’s volunteer experiences over time and their manifestation in the built environment. The capacity of cultural heritage to effectively and comprehensively represent those experiences and map key contributions to building and shaping communities is also tested. Research confirms a direct correlation between broader historical developments and women’s volunteer responses in groups. Women reacted proactively, spontaneously and creatively to changing community needs. They committed their collective voluntary labour to address shortcomings in government policies and emerging inequalities in society, to support a nation at war and the work of various Church denominations. These findings validated women’s creative and progressive agency in volunteer-based groups to building and shaping communities, and confirmed their contribution was sustained and consistent over time. Although most volunteer experiences reflected traditional definitions of gender, more expansive opportunities were available to office-bearers, as well as those involved in self-development groups, the suffrage movement and mobilising for the war effort. Government policy did, however, attempt to restrict women’s voluntary wartime work to conventional roles, as did male-dominated ecclesiastical views within church-affiliated groups. Regardless of work or group type, evidence suggests that participation was nevertheless an empowering process. It enriched the lives of many women and facilitated their transition from the private domain of home and family to the public arena. The pioneering nature of women’s voluntary work, especially in nineteenth century Queensland, further enhanced that journey. While voluntary work over this period was dominated mostly by married upper- and middle-class women, single women were well represented. All groups benefitted from career volunteers, who displayed high levels of participation within and across groups. Many participants were motivated by strong altruist ideals, although patriotism and government propaganda played a major role during the war years, as did the influence of the Church and strong Christian beliefs for those involved in groups with a religious affiliation. A key outcome of the study is the identification of some 700 cultural heritages sites, just over half of which appear on an indicative list of places by theme. They reflect the diversity and development of women’s volunteer experiences in Queensland between 1859 and 1959 and provide tangible evidence of their sustained contribution in volunteer-based groups to processes that build and shape communities over time. Collectively, however, these sites tend to strengthen the conservative view of women’s roles, in that they were associated with services which often reflected concerns about issues impacting on home and family. Groups pursuing social or political reform were also disadvantaged in that their sites were restricted in number and frequently limited to public space and bureaucratic or ministerial offices. Likewise, the efforts of Church-based groups were diffused, given their sites of association were, in many cases, not their own. As the first of its kind in a Queensland setting, this study provides substantive findings in an area not well served by scholarly researchers in the past. It also offers an alternative gender-sensitive approach to establishing links between women’s history and cultural heritage. In addition, it has the potential to lift the visibility of women’s voluntary work through landmark recognition and historic preservation programs, whether as new entries on heritage registers, additional information for existing listings, plaque placement or memorial programs and heritage trails.

Building knowledge for policy and practice in out-of-home care: exploring the boundaries of systematic mapping

Belinda Mayfield — 2012-06-20T00:00:00Z

Abstract The impetus for this study arose from the current challenges facing out-of-home care systems in Australia and the urgent need to improve the outcomes for the vulnerable children and young people and their families who experience these systems. The central focus of the study is the notion of accessibility of the literature as a source of knowledge to inform out-of-home care policy and practice. Accessibility is conceptualised as a fundamental precursor to the application of knowledge. This issue was selected as it appeared to have been largely glossed over in knowledge utilisation studies, indicating that it required focused attention. The overall aim of this study was to investigate the issue of the accessibility of the out-of-home care literature as a source of knowledge to professionals working in roles which influence policy and best practice in this field. The significance of the study lies in the scope, perspective, and research design, creating potential for the findings to have relevance at both a content and methodological level. Systematic mapping is an emerging approach and maps aim to identify the majority of available literature on a broad topic, as a tool for readily accessing and interrogating the research literature (Clapton, Rutter & Sharif, 2009). Specifically, the aims of the study were to: • Develop a systematic map of the out-of-home care literature by systematically searching and organising the out-of-home care literature into relevant content areas; • Provide a descriptive analysis of the composition of the available literature (as identified in the systematic map) to identify gaps and areas where there appears to be substantial knowledge; • Gain insight about how different user roles view their knowledge needs and the barriers they experience in accessing relevant literature; and • Gather feedback about the utility and limitations of the systematic map from the perspective of different user roles. To meet the research aims, the study was conducted in two phases: the first phase involved developing a systematic map of the out-of-home care literature; and the second phase involved in-depth semi-structured interviews with key informants from different user roles, including researchers, policy makers, program managers and practitioners. While each phase of the study was distinct, relying on different methods, the two phases were interrelated, contributing to the achievement of the overall aims of the study. The systematic map developed in the first phase had dual purposes. Firstly, the purpose was to identify the majority of readily available out-of-home care literature for the period 1995 to 2008, and to provide a basis for a descriptive analysis of the composition of the literature, relevant to specific content areas. The second purpose of the map was as a practical resource and a tool to engage informants in the semi-structured interview process. The foci of the interviews were to gain in-depth insight into knowledge needs and barriers and enablers to the accessibility the out-of-home care literature and to gather feedback on the utility and limitations of the systematic map, from the perspective of different user roles. In reflecting on the outcomes, this study has led to the creation of an information resource in the form of a systematic map of the out-of-home care literature, which categorises over 4,000 publications reporting research, theory, policy and practice literature. One of the conclusions drawn from this study is that the out-of-home care systematic map appears to have potential utility in a range of areas including: as a resource to readily locate relevant publications for interrogation in response to specific practice or policy related questions; to identify key methodological and content gaps in the knowledge base in a planned and systematic way; and as a tool to engage with users in discussion about knowledge needs. The overall findings add weight to the existing body of research examining barriers to knowledge utilisation, which identify issues such as time constraints, volume of literature and physical and intellectual accessibility, along with lack of motivation and organisational support, as potential barriers (Barratt, 2003; H. Elliott & Popay, 2000; McSherry, Artley, & Halloran, 2006; Randall, Cowley, & Tomlinson, 2000; Straus & Haynes, 2009). An additional key insight from this research is that barriers do not necessarily occur in isolation or independently. When a number of issues are compounded a sense of being overwhelmed may result, which in turn becomes a barrier in itself. This thesis provides new contributions to knowledge in the areas of understanding the barriers to the accessibility of the literature, the knowledge needs of different user groups and systematic review methodology. The conclusion was reached that knowledge needs extend beyond research literature and that narrow conceptualisations of knowledge for instrumental use have limitations in an applied field. In light of the composition of the out-of-home care literature, the case for drawing together research literature reporting studies with diverse methodologies in a systematic map seems incontestable. This study, however, by challenging conventional boundaries also highlights the potential of incorporating non-empirical literature in systematic maps. The conclusions drawn from this study have implications for out-of-home care policy and practice, further research in this field and systematic mapping methodology. In particular, the findings have implications for understanding the knowledge needs of user groups in an applied field, and managing the uncertainty created by the limitations of the out-of-home care knowledge base in an accountable and transparent way. The overall findings of this study indicate that for this field to move beyond the rhetoric of evidence-informed policy and practice, emphasis must be given to a balanced approach to addressing research gaps, not only in primary research, but secondary analysis to support utilisation of the knowledge that is currently available.

Built Form and Culture: A Case Study of Gilbertese Architecture

Hockings, John — 2008-11-21T00:00:00Z

The last two decades of architectural studies have been marked by a renewal of interest in human behaviour and how it is related to the environments we inhabit. This interest has stemmed from the recognition that much contemporary architecture, in its pursuit of economic technological efficiency, pays little or no attention to its human context. As part of the attempt to re-establish this context, designers and scholars alike have seen the need to increase our understanding of the nature of the relationship between man and his spatial environment. The aim of this thesis is to examine the aspect of this relationship which emerges from the premise that the formal 'rules' of culture are one of the means used by man in the process of interpreting his spatial environment. Based on a field study in the Gilbert Islands in the western Pacific, this research outlines the specific nature of the cultural rules used by the Gilbertese in this process, and examines how the process has changed over time. The thesis is divided into four sections. The Introduction outlines the argument for this type of study in more detail, and explains the theoretical framework developed to relate man, culture, and built form. Also included are the research methodologies used, and a brief physical description of the study area. In the second section, Part One, four distinct units of traditional Gilbertese settlement pattern are identified - the home, the clan hamlet, the meeting house, and the island as a whole. Each is analysed as a physical environment, the arrangement and use of which were developed by the Gilbertese in accordance with certain relevant cultural practices. Taken as a whole Part One gives an overall outline of the important traditional relationships between built form and culture. In the third section, Part Two, the impact of Western occupation and influence upon the traditional pattern of relationships is examined. Through an analysis of the manner in which the Gilbertese manipulated those relationships in response to such influences, it became possible to draw conclusions as to the workings of Gilbertese built form and culture, one against the other. The eventual understanding of the built form/culture relationship, arrived at through the analyses conducted in Parts One and Two, is outlined in the final section, Concluding Remarks. The argument is again supported by notable examples cited earlier in the main text. The specific conclusions so drawn are then synthesised into a more general conclusion of interest to scholars and practitioners of architecture alike. The thesis begins with the premise that culture would be a determining factor of much of the meaning which people read into their spatial environment. But, as evidence is collected and conclusions drawn, it is shown that such a view (suggesting that culture is used by people as a means of comprehending their architectural environment) cannot be sustained, and that the Gilbertese in fact use their architecture to explore and explain cultural ideas. So it is deduced that it is preferable to treat architecture as a means to a cultural end, thus avoiding the temptation, inherent in the initial premise, to attribute a falsely deterministic role to culture. Most importantly, it allows architecture to be seen as an active element in the cultural process rather than as a passive receptacle of cultural meaning.