UQ Theses (RHD) - Official collection - UQ eSpace

The role of patched1 in mammalian facial dysmorphology

Metzis, Vicki — 2012-10-31T00:00:00Z

THE ROLE OF PHASE VARIABLE TYPE III RESTRICTION-MODIFICATION SYSTEMS IN GENE REGULATION

Srikhanta, Yogitha — 2008-11-21T00:00:00Z

Phase variation, the high frequency reversible switching of gene expression, is a common feature of host-adapted bacterial pathogens and is generally associated with genes encoding surface factors. Phase variation results in genetically and phenotypically diverse populations, providing a strategy for rapid adaptation to changes within the host environment and evading immune responses. However, in a growing number of host-adapted pathogens, phase variation has been found to occur in genes encoding methyltransferases (mod genes) associated with type III restrictionmodification (R-M) systems. R-M systems traditionally confer protection against foreign DNA, and several roles have been proposed for phase variable R-M systems based on DNA restriction function. The existence of phase variable methyltransferases raises the possibility of further functions for R-M systems such as gene regulation. In this thesis the role of a phase variable methyltransferase (mod) associated with a type III R-M system of Haemophilus influenzae strain Rd was investigated. Microarray expression analysis comparing a wild-type strain expressing mod to a mod knockout mutant strain, revealed altered expression of 15 genes under Mod control, some of which were virulence associated. This key finding confirmed that this phase variable methyltransferase coordinates the random switching of expression of multiple genes. Phylogenetic studies were used to analyse phase variable mod genes associated with type III R-M systems in the human pathogens Neisseria meningitidis and Neisseria gonorrhoeae revealing that these organisms have two distinct mod genes - modA and modB. There are also distinct alleles of modA and modB that differ only in their DNA recognition domain. Phylogenetic analysis was also used to create an up-to-date list of potentially phase variable type III R-M systems present within other host-adapted organisms. To confirm whether phase variable methyltransferases controlled gene expression in other pathogens, the phase variable modA genes of Neisseria were studied. Mutant strains lacking the modA11, modA12 or modA13 genes were made and their phenotype analysed. Microarray analysis revealed that in all three modA alleles multiple genes were either up- or down-regulated, some of which were virulence associated. For example, in N. meningitidis (modA11), 80 genes were differentially expressed including the vaccine antigen candidates lactoferrin binding proteins A and B. Functional studies in N. gonorrhoeae confirmed that wild-type FA1090 modA13 ON and FA1090modA13::kan mutant strains have distinct phenotypes in antimicrobial resistance, a primary human cervical epithelial cell model of infection and biofilm formation. In summary, this thesis provides experimental confirmation that in three important human pathogens, H. influenzae, N. meningitidis and N. gonorrhoeae, alteration of expression of a type III DNA-methyltransferase causes switching of multiple genes. This novel genetic system has been termed the phasevarion (phase variable regulon). The wide distribution of phase variable mod genes indicates that this may be a common strategy used by host-adapted bacterial pathogens to randomly switch between distinct differentiated cell types.

THE ROLE OF PROTEASE IN UNLOCKING THE NUTRITIVE VALUE OF SORGHUM GRAIN FOR PIGS

Avril Finn — 2011-10-18T00:00:00Z

In Australia, and especially Queensland, sorghum is an important animal feed grain due to its drought resistance and heat tolerance. In many instances sorghum is thought to have a lower nutritive value compared to other cereal grains by pig producers due to poor pig performance when fed the grain with respect to rate of gain (ROG), average daily intake (ADI) and feed conversion ratio (FCR). An experiment was conducted on 640 Large White pigs (7.0 to 9.2 kgs) to evaluate the effects of different grain types and cultivars on performance of weaned pigs. The pigs were fed complete diets for 21 days containing 65% of one of 32 test grains (11 sorghum, 9 wheat, 7 barley and 5 triticale) with a calculated DE of 14 MJ/kg and lysine content of 0.90 g/MJ DE. Overall, sorghum was shown to have a significantly (P<0.05) negative effect on pig performance when compared to wheat, barley and triticale. However, it was also shown that some sorghum cultivars could perform just as well as the other grain types. To determine whether pig performance was affected by animal age, a second experiment was conducted on 120 Large White male pigs (16 to 25 kgs) to evaluate the effects of different sorghum cultivars. The pigs were fed complete diets for 21 days containing 82% of one of 10 sorghum grains (one yellow and nine red) with a calculated DE of 14 MJ/kg and lysine content of 1.13 g/MJ DE. Grower pigs fed different varieties of sorghum grains showed statistically significant (P<0.05) differences in ROG, but not ADI or FCR. The performance of the grower pigs compared to the weaner pigs on the same 10 test sorghum grains showed no correlation which leads to the conclusion that the age of a pig can affect its growth performance when fed the same grain. However, in contrast to the modest growth performance of pigs fed sorghum, the total digestible energy (DE) of sorghum is either similar or higher than some grains e.g. wheat. Therefore a third experiment was conducted on 42 Large White male pigs (32 to 37 kgs) to investigate whether DE values in grower pigs from both apparent ileal digested (AID) energy and apparent total tract digested (ATTD) energy measurements vary between different cereal grains. The pigs were fed complete diets containing 95% of each of the 32 grains used earlier with a calculated DE of 13 MJ/kg and lysine content of 0.70 g/MJ DE. There were highly significant (P<0.001) differences in the DE between grain types. The highest DE was from sorghum and wheat, followed by triticale, and the lowest for barley. Grain cultivar had a highly significant effect (P<0.001) on the ATTD energy for the diet on an as received (AR) basis, and the ATTD energy for the grain as an ingredient on an AR and dry matter (DM) basis. However, grain cultivar had no effect on the AID energy for the diet. There was also a significant (P<0.05) effect of the grain variety on the ratio of the diet AID to ATTD with wheat having the highest ratio followed by sorghum, triticale, and barley. One reason for poorer pig performance, when fed sorghum may be due to starch/protein interactions in the endosperm matrix restricting digestion of both starch and (kafirin) protein. Therefore an in vitro experiment was conducted using two sorghum cultivars, the yellow seeded Liberty and a red seed coat hybrid (Red1) to determine the efficacy of specific exogenous enzymes on the digestion of sorghum kafirins. Five exogenous enzymes, xylanase, beta-glucanase, protease, amylase and phytase were used in combination and individually. Enzymes were added to hammer milled whole grain then a protein extraction and sodium dodecyl sulfate polycrylamide gel electrophoresis (SDS-PAGE) analysis was undertaken, which showed that digestion of sorghum α-, β- and γ-kafirins was improved by the addition of protease either on its own or in combination with other enzymes. However, in combination with xylanase, beta-glucanase and amylase it appeared to lose its efficacy. Due to the positive effect of exogenous protease in vitro, an in vivo experiment with 144 Large White male pigs (7 to 9 kgs) was conducted to evaluate the addition of protease enzyme at four different levels (0ppm, 50ppm, 100ppm and 500ppm) to a complete diet containing 65% of either Liberty (yellow), Buster (red) sorghum and a wheat control, with a calculated digestible energy (DE) of 14.57 MJ/kg and an available lysine content of 1.55 g/MJ DE. At 0-21 days, for the highest protease level (500ppm) both sorghums performed better than in the absence of protease, and similarly to the wheat control in terms of FCR. In conclusion, although sorghum and wheat show higher AID and ATTD energy compared to triticale and barley, sorghum typically gives poorer pig performance than wheat, barley and triticale. However, selection of appropriate sorghum cultivars and, particularly, treatment with exogenous protease show promise as means of obtaining pig growth performance and feed conversion efficiency similar to or better than that of other cereals used in Australia.

The role of RSVP distractors in the effect of concurrent extraneous cognitive load on AB task performance

Samantha Howard — 2011-04-08T00:00:00Z

The attentional blink (AB) is the impaired ability to identify a second target (e.g., letter) presented among a rapid serial visual presentation (RSVP) of distractors (e.g., digits) when the second target (T2) occurs within approximately 500 ms of a correctly identified first target (T1). One of the more intriguing findings to emerge from recent AB literature is that an observer will show a significantly reduced AB and overall better target accuracy if they simultaneously perform a task that is extraneous to the RSVP (Olivers & Nieuwenhuis, 2005; 2006). Contemporary accounts of this ‘additional task benefit’ emphasise the role of distractors, with the most recent theories highlighting the importance of the processes occurring at T1+1 distractor selection (Olivers & Meeter, 2009; Olivers, van der Stigchel, & Hulleman, 2007). The purpose of this thesis is to test the following three general questions 1) whether the T1+1 distractor item plays a crucial role in the additional task benefit, 2) whether the additional task benefit is sensitive to the level of discriminability between targets and distractors, and 3) whether distractors are essential for demonstrating the additional task benefit. A preliminary set of experiments replicated Olivers and Nieuwenhuis’ (2006) finding of an additional task benefit on target identification accuracy in a standard AB task. In a set of follow-up AB experiments, RSVP targets were four-letter words and distractors were orthographically acceptable (word-similar) or orthographically unacceptable (word-dissimilar) non-words. The findings indicated that a low degree of discriminability between targets and distractors is pivotal for showing the beneficial effect of secondary task load. It was also shown that reducing the effectiveness of the T1+1 mask through distractor repetition eliminates the additional task benefit. These findings were extended in two final experiments demonstrating an additional task benefit when there were no distractors between T1 and T2, but no additional task benefit in an RSVP of successive target stimuli. These results suggest that the effect of secondary task load principally depends on the presence of T1 and an adequate temporal frame in which this initial target may be processed before the onset of T2. Taken together, the project’s findings are inconsistent with contemporary distractor-based models of the secondary task benefit on AB task performance. Instead, the findings match recent accounts of the AB, which emphasise the dynamics of attentional processes involved in target selection.

The Role of Sox18 in Blood Vessel Development

Meredith Downes — 2008-11-06T00:00:00Z

The Role of Stated Organizational Values in Times of Change and Crisis

Stewart Arnold — 2010-03-18T00:00:00Z

Weick (2006) calls for researchers to investigate how employees ‘hold it together’ during periods when organizational routine and order are challenged. This thesis focuses on employee experiences during two types of organizational upheaval: periods of planned, large-scale organizational change and periods of organizational crisis triggered by external events. In both conditions, employees can react negatively. This leads to failure to cope with the current situation and with future situations that pose similar threats and challenges. On the other hand, if employees can make sense of a threatening, challenging situation, the outcomes are more positive for them as individuals and for the organization as a whole. Weick’s (1988) concept of sensemaking is used as a guiding framework for investigating the experiences, attitudes, and actions reported by employees in times of organizational change and crisis. The general assertion of the thesis is that the espoused and enacted values of an organization provide sensemaking cues to employees in difficult times. More specifically, the role of stated organizational values is examined. Organizational values are often stated as a set of principles that provide guidance for employees, particularly as part of a managing-by-values approach. The context for the research program is the healthcare industry, because values are very important for healthcare employees. Moreover, healthcare organizations must continue to function optimally during challenging conditions. Three research studies are reported. Study 1 was conducted in an Australian public hospital that was undergoing large-scale change. Thirty-five employees from a range of occupations were interviewed midway through the five-year period of change. Thematic analysis of their interviews revealed that employees mostly reported negative experiences of the change program. Furthermore, employees made sense of the change program by focusing on specific cues in their situation. One such cue was the organization’s strongly promoted set of ‘core values’. The stated values were seen to be a visible symbol of the hospital’s principles, but there were negative perceptions about how well these principles were enacted. Study 2 was conducted in a public hospital in Singapore exposed to a crisis situation due to the SARS virus in 2003. Thirty-one employees from a range of occupations were interviewed four months after the outbreak had ended. Twenty of these participants returned for a second interview, one week after the first interview. A card sort procedure and thematic analysis of the interview data were used to investigate employees’ experiences of the crisis. Results revealed that employees made sense of the crisis through identification with their profession and their organization. They also perceived that the hospital’s actions during the crisis were consistent with its written set of organizational values. In addition, employees identified a number of organizational citizenship behaviors (OCBs) that they had shown during the crisis. Study 3 was conducted at three hospitals in Singapore. A pilot study involved 24 employees from a public hospital. They engaged in a focus group discussion about professionalism and they refined a set of hospital-specific employee behaviors that could potentially be classified as OCBs. The main study involved survey completion by a stratified sample of employees from another public hospital (n= 214) and from a private hospital (n=184). All respondents were invited to complete a second survey (measuring related variables) three weeks after the first survey. Analysis of 301 usable survey responses revealed findings that contribute to different literatures. Firstly, asking respondents to rate OCBs according to whether they were voluntary, unrewarded, and beneficial to the organization, revealed that many OCB items used in previous research were not perceived as being ‘true OCBs’ by the survey respondents. Furthermore, despite the use of many possible OCB dimensions, the true OCB items were factor analyzed into just two factors. One factor reflected OCBOs, which are behaviors directed towards the organization as a whole, while the other factor reflected OCBIs, which are behaviors directed towards other individuals. A second contribution is the suggestion that employees’ sense of ‘professionalism’ is a single construct. Survey respondents did not distinguish between professional identification and professional commitment in the same way as organizational identification and commitment were differentiated. Professionalism was weakly related to tendency to engage in OCBOs and more strongly related to tendency to engage in OCBIs. Finally, the main contribution to the values literature is the development of the concept of ‘organizational values integrity’ (OVI). This is conceptualized as the perceived alignment between organizational actions and organizational words, especially those words espoused in values statements. Structural equation modeling revealed that OVI influenced organizational identification and organizational commitment, which both mediated the impact of OVI on OCBOs. Furthermore, OVI had a direct impact on OCBOs. Overall, this thesis highlights employee perceptions that the organization acts in ways that are aligned to its stated values as important influences on employee attitudes and OCBs, particularly in difficult times. Implications for managerial practice and further research are discussed.

The role of summer dormancy in improving survival of temperate perennial pasture grasses in drought-prone environments

Norton, Mark Roger — 2008-11-21T00:00:00Z

The poor survival of perennial pasture grasses is a major constraint to agricultural systems where summers are characterised by long, severe droughts and high temperatures. The search for grasses with superior tolerance to these conditions has resulted in a re-awakening of interest in the summer dormancy trait leading to the recent release of several summer dormant cultivars. This has led to renewed questioning about the nature of summer dormancy particularly as the definition of the trait is unclear. Therefore, this research has aimed to strengthen understanding of summer dormancy in the pasture grasses Dactylis glomerata L. (cocksfoot), Festuca arundinacea Schreb. (tall fescue) and Phalaris aquatica L. (phalaris) by studying two cultivars contrasting in the expression of summer dormancy from each species. A range of field trials in the south of France aimed to identify key physiological mechanisms whereby summer dormancy enhances survival over long, dry summers by concentrating on the effects of different levels of summer water supply and plant maturity. Field trials in that region also compared and evaluated several methods to measure the intensity of summer dormancy and developed a new method based on herbage production from irrigated summer culture. Growth chamber trials with small pots studied the relationship between temperature and the expression of summer dormancy by comparing the growth response to a range of temperatures of two cohorts of plants contrasting in exposure to conditions aimed to induce summer dormancy. Finally, winter research conducted in pots in the glasshouse subjected plants to drying cycles to study dehydration tolerance and avoidance and related these to the expression of the summer dormancy which had been observed in the summer field studies. The component mechanisms of summer dormancy were clearly expressed under full summer irrigation by reproductive plants which had been vernalised and although present in younger, spring-sown plants they were approx. 40% less intense while the tall fescue cv only expressed dormancy if subjected to prior drought. Expression began in late spring/early summer and included growth cessation and herbage senescence resulting in substantially less summer evapotranspiration in the dormant tall fescue and cocksfoot swards compared to their summer active counterparts. The dormant cocksfoot under drought dehydrated to -6.7 MPa and even under irrigation dehydration to -3 MPa occurred . In contrast, under irrigation the dormant tall fescue and phalaris cvs remained hydrated. Dehydrin expression increased in all cvs as water deficit intensified but while expression declined after a storm in the non-dormant cvs (in response to increased water status), levels remained uniformly high in the three dormant cvs. The summer dormant tall fescue maintained full sward cover after summer droughts of 116 and 144 days whereas cover in the summer active cv fell by approx. 25%. Similar sward loss (22%) occurred in a summer active cocksfoot, in contrast to the summer dormant cv after a 144 day drought. No survival advantage for the summer dormant cv was measured in phalaris although this seemed to be due to unique field trial site characteristics. Five methods for summer dormancy measurement varying according to summer water availability, i.e., full irrigation, mid-summer storm and complete drought, and assessment method, viz., herbage production measurement or visual estimation of herbage senescence, were compared and evaluated. A method using the herbage harvested from irrigated summer culture was developed. Summer dormancy is best measured under non-limiting moisture, because assessing the trait under complete drought can result in false scores, e.g. Medly cocksfoot was moderately dormant under drought (6/10), but non-dormant under full summer irrigation or after a storm (1-2/10). Dormancy was scored equally well by measuring herbage production or by visually assessing the level of herbage senescence. The examination of the effect of temperature on summer dormancy questioned whether dormancy is independent of temperature or is simply a decline in growth in response to high summer temperatures. In cocksfoot the decline associated with summer dormancy (approx. 100%) was independent from any which occurred as a result of high temperatures. In tall fescue, despite indications that dormancy was a separate effect it was not possible to definitively separate the effects of rising temperature from prior dormancy induction suggesting the need for further research. Inconsistent and inconclusive results occurred in phalaris suggesting that small pot culture is inappropriate for studying dormancy in this species. Subjecting plants to drying cycles in a winter glasshouse environment demonstrated that dehydration tolerance, dehydration avoidance and summer dormancy are separate responses able to be independently expressed. In cocksfoot and tall fescue two highly dehydration-avoiding cvs also expressed high levels of dormancy in summer as reproductive plants although a summer active cocksfoot was also highly dehydration-avoiding. In contrast, the highly summer dormant phalaris cvs showed no greater levels of dehydration avoidance/tolerance than much less dormant cvs. The research has identified key mechanisms of drought survival as being component, defining characteristics of summer dormancy and has also demonstrated robust screening methods to extend utilisation of the trait in plant improvement.

The Role of the Internet in the Lives of People with Traumatic Brain Injury

Jennifer Egan — 2010-06-17T00:00:00Z

Psychosocial factors represent complex and enduring challenges for people with a traumatic brain injury (TBI), their families and health and rehabilitation systems, particularly in relation to social isolation, change/loss of role and identity issues. Traditional rehabilitation approaches to psychosocial issues target cognitive rehabilitation and psychological adjustment of the individual with a TBI, which reflect the medical model of health. However, the International Classification of Functioning, Disability and Health (ICF) ushers a new era in TBI research and practice, which advances the conceptualisation of disability, to include the impact of environmental factors. The ICF identifies the Internet as one such environmental factor, which has the potential to facilitate or impede social participation of people with a disability. Empirical studies suggest the potential of the Internet to empower people with disabilities, via opportunities for social connection; social support; social role participation and identity experimentation. However, research has focused on people with sensory, physical, and mental health issues, with little known of the potential of the Internet for people with a TBI. This area of deficit warrants investigation, in view of the potential of the Internet to address many dimensions of psychosocial concern following TBI. This study explores the role of the Internet in the lives of people with a TBI, with a focus on the potential of the Internet to influence psychosocial recovery. Psychosocial recovery is conceptualised as the reconstruction of a positive identity, as found in subjective accounts of people with a TBI (Lewington, 1996), and strongly supported in the mental health consumer literature. Using a social constructionist approach, this study explores how people with a TBI use the Internet and how they make meaning of their Internet experience. This approach acknowledges the socially situated nature of Internet use and validates the subjective accounts of people with a TBI, whose perspectives are underrepresented in the rehabilitation literature. This study also trials the method of email-facilitated qualitative interviewing, to address face-to-face interviewing barriers, relating to cognitive-linguistic impairments (Lloyd, Gatherer, & Kalsy, 2006; Paterson & Scott-Findley, 2002). Thus, the Internet is the focus of the enquiry and the mediator of the method. The findings highlight the positive potential of the Internet to facilitate social participation for people with a TBI. Participants reported that features such as asynchronicity, reduced cues and anonymity made the Internet an accessible and usable technology, for social connection; social support; social role participation and identity reconstruction. A major theme emerging from the data was control of self, which this study conceptually linked to identity reconstruction and psychosocial recovery. Findings allayed concerns regarding the negative potential of the Internet to increase social isolation of vulnerable people, as participants regarded face-to-face relationships as more fulfilling than online friendships, supporting classic communication theories (Rice, 1987; Rice & Love, 1987), which propose that the Internet is a less personal medium than face-to-face communication, due to the feature of reduced cues. The findings of the method indicated that email facilitated qualitative interviewing addressed face-to-face interviewing barriers related to cognitive linguistic impairments; mobility factors; chronic health issues and environmental stimuli. Most participants indicated that asynchronicity, reduced cues, and anonymity facilitated control of communication, cognition and identity, thus enabling interview participation. The method had also advantages for the researcher, including time for reflection and the ability to yield richer data than in face-to-face contexts. However, the method was resource intensive, requiring information technology proficiency, familiarly with the impact of cognitive-linguistic impairments in online contexts and counselling experience. In addition, ethical guidelines required the involvement of a support person for the emotional protection of participants. This study makes two contributions to knowledge. One contribution relates to the potential of the Internet as an ICF environmental factor to address long-term psychosocial concerns, in addition to positively influencing psychosocial recovery from TBI, as reported by participants. This study contributes to a new era of research, which considers the impact of environmental factors on the experience of TBI, as framed by the ICF. The second contribution relates to the method of email facilitated qualitative interviewing, which advances knowledge of interviewing barriers for people with a TBI and addresses calls for innovative methods with this population. The findings of the method bring into question long held assumptions about the capacity of people with a TBI to participate in research and have implications for research design in qualitative and quantitative methodologies.

The role of the national government in facilitating innovation within the tourism industry: a case from Norway

Mei, Xiang Ying — 2012-09-05T20:35:10Z

THE ROLE OF THE PLANT CELL WALL ON THE BIOACCESSIBILITY AND BIOAVAILABILITY OF ANTHOCYANINS AND PHENOLIC ACIDS RELEASED FROM FRUITS AND VEGETABLES.

Anneline Padayachee — 2012-06-28T00:00:00Z

Fruits and vegetables are well known sources of vitamins, minerals and fibre as well as polyphenolic compounds and other phytonutrients. Extensive research into the chemoprotective benefits of plant-based foods has found that such compounds and their metabolites have antioxidant, anti-inflammatory and/or anti-carcinogenic properties. Whilst the health benefits associated with high dietary intake of fruit and vegetable polyphenols is a well researched field, the role of the plant cell wall on the bioaccessibility of these compounds is not. Polyphenolic and other nutrient compounds are located within the vacuole of plant cells surrounded by a lipid membrane and thereby separated from the plant cell wall which encapsulates the cell. In order for polyphenols and other nutrients to be bioavailable (i.e. absorbed during digestion through the gastrointestinal tract), they must first become bioaccessible (i.e. released from the plant cell ready to be absorbed by the body). In order for nutrients to be bioaccessible, the plant cell wall needs to be breached with the consequent possibility of binding between nutrients and plant cell walls. This thesis explores the nature of interactions between plant cell walls and two important classes of polyphenolic phytonutrients, anthocyanins and phenolic acids. The main structural constituent of the fruit and vegetable cell wall is cellulose, which is surrounded by a matrix of pectin and hemicelluloses, and at times lignin. Lignin directly affects the textural and palatability qualities of plant foods, and is generally not present in large amounts in fruits and vegetables. Cellulose fibres are tough and insoluble, and hence able to resist substantial force and provide support to the plant cells, whilst pectin increases the flexibility through formation of a co-extensive network with the rigid cellulose fibre network. The degree of methyl esterification (DE) of carboxyl groups is commonly used to differentiate pectins and to control network formation. The role of cell walls in polyphenol bioaccessibility has not been researched extensively. Rupture of the cell wall during mastication or processing (e.g. pureeing or juicing) results in polyphenols being released from the cell vacuole with consequent contact with cell walls for the first time, with the potential for binding interactions to occur. The human upper gastrointestinal tract (stomach and small intestine (S.I.) is unable to digest plant cell walls. Therefore if polyphenols bound to plant cell walls at the point of ingestion are not released from the cell wall material during transit through the gastric and small intestinal digestive phases, they will be carried by the cell walls to the large intestine where they may be released by bacterial fermentation of cell wall polymers and potentially further metabolised by bacteria before being either absorbed or excreted. This research fills several major gaps in current knowledge by: 1) identifying potential mechanisms for polyphenol-plant cell wall interactions; 2) assessing the bioaccessibility of polyphenols in a real vegetable system; and 3) examining the release of plant cell wall-bound polyphenols during gastric and S.I. digestion and the potential delivery of polyphenols to the colon. The extent of anthocyanin and phenolic acid interaction with cell wall components was investigated by monitoring the rate of polyphenol depletion from diluted purple carrot juice concentrate in the presence of pure cellulose or cellulose-pectin composites containing either low DE or high DE pectins, produced by the bacterium Gluconacetobacter xylinus. Binding of anthocyanins to plant cell wall components seems to be a 2-stage process with initially (1 hour) a limited amount (13-18%) of anthocyanins bound to the surface of the cellulose or cellulose-pectin composite. Whilst anthocyanins bound to both cellulose and pectin, more were bound to pectin. With prolonged exposure (7 days) to cell wall material, a gradual increase in anthocyanin binding occurred with approximately 35% binding to cellulose and the high DE composite and up to 80% binding to the low DE composite. This may be due to anthocyanins stacking on top of a base layer. Support for localised deposition of anthocyanins was found from confocal microscopy which showed apparent local high concentrations of anthocyanins alongside regions with much less, if any, bound anthocyanins. There does not seem to be molecular selectivity as depletion from solution of individual anthocyanin molecules is similar throughout the binding process. Phenolic acid depletion from solution in the presence of model cell walls also occurred. However unlike anthocyanins, more phenolic acids were bound to the pure cellulose initially than to the cellulose-pectin composites. Phenolic acid depletion was rapid, with approximately 20% phenolic acids binding to cell wall components within the first hour. This gradually increased to approximately 35% (low DE composite) and 50% (high DE composite and pure cellulose) over 14 days contact time. Additionally phenolic acid depletion from different concentrations of diluted purple carrot juice concentrate was similar indicating that cell walls may have a limited saturation level for binding phenolic acids. Conversely, doubling the concentration of free anthocyanins available led to at least twice as much binding with cell wall components. This indicates that whilst anthocyanin binding is slow, it may not be limited by available binding sites. Extrapolation of data from these model systems to carrot puree suggests that significant amounts of anthocyanins and phenolic acids could bind to the plant cell wall, potentially restricting their bioavailability in the S.I. In order to ascertain the potential extent of polyphenol delivery to the large intestine via plant fibre in a real food system, polyphenols bound to cell wall material in a black carrot puree were subjected to simulated gastric and small intestinal digestion. It was found that the majority of available hydrophilic polyphenols derived from black carrots bound to the PCW matter with only ~ 36 % of the total phenolic acids (~ 1.2 mg/g puree) and 30 % of anthocyanins (1.3 mg/g puree) in the black carrot puree being released into the liquid phase. Approximately 30 % of the bound phenolic acids and anthocyanins could be extracted with acidified methanol. However, only <5 % of anthocyanins and phenolic acids were released during simulated gastric and small intestinal digestion. This is in agreement with results from the model cell wall system where the majority of bound polyphenols remained bound after simulated gastric and small intestinal digestion indicating that the binding mechanism between polyphenols and cell wall components is sufficiently strong to resist pH changes during the digestive process. This may be due to a 3-phase mechanism with initial random binding of anthocyanins and phenolic acids to cellulose fibres followed by further deposition of anthocyanins and phenolic acids, finally resulting in penetration into the internal cavity of the fibre of at least some polyphenols. As almost all polyphenols bound to cell wall components remain bound during simulated gastric and small intestinal digestion, they would be expected to be delivered to the large intestine where fermentation and metabolism by gut bacteria can occur. The extent of release and uptake of polyphenols bound to cell walls by gut bacteria fermentation and the effect on large bowel health should be addressed in future studies.

The role of the ubiquitin protein ligase, Nedd4-2, in neuronal development

Prudence Donovan — 2012-03-28T00:00:00Z

Correct ontogeny of the nervous system is reliant upon exquisite regulation of exogenous growth factors and their cellular reception. Integration of a myriad of signalling pathways during the development of the nervous system results in up to 100 billion nerve cells differentiating and migrating to take the their place in the elegant neuronal network that underpins brain homeostasis. The importance of such receptor ligand interactions to the proper initiation of neuronal differentiation, outgrowth and innervation has been demonstrated using a variety of structure- function studies, analysis of knockout animal models, protein-protein interactions and behavioural studies. Despite this, at present, knowledge concerning how such a vast array of signalling pathways are coordinately regulated to achieve the appropriate temporal and spatial regulation of neurogenic proteins is deficient. Modulation of the functional protein output of cell can be regulated by ubiquitination. Attachment of ubiquitin to a target protein is a post-translation modification carried out primarily by ubiquitin protein ligases that bind to consensus motifs on target proteins and conjugate ubiquitin chains to lysine residues within that protein. This process is known to label proteins for recycling or degradation in the proteasome. Thereby providing a mechanism for the removal and attenuation of a proteins signalling potential-when and where it is required. Such a modification is rapid and provides regulation of a protein that is context dependent and easily reversible, therefore providing a on/off switching mechanism, appropriate to the formation complex networks, as seen during neuronal development. Nedd4-2 is an ubiquitin protein ligase that is developmentally regulated; the protein was first identified from a subtractive cDNA library as developmentally down-regulated transcript in the brain. The expression of Nedd4-2 peaks at the time of neurogenesis and is maintained at significantly lower levels in the adult brain. Presently, the knowledge concerning the regulation of Nedd4-2, protein recruitment by Nedd4-2 and how this regulates neuronal development is lacking. Early studies of protein recruitment by Nedd4-2 indicated that it binds to target proteins through a consensus PY motif, despite a small list of proteins being identified and characterized as targets of Nedd4-2 mediated proteolytic degradation; the role of Nedd4-2 has largely not been characterized in the mammalian brain. Therefore, the key focus of this thesis was to examine the role of Nedd4-2, in neuronal development by defining and pinpointing where and how Nedd4-2 influences initiation of neurite development,differentiation and survival. The work presented in this thesis addresses this by establishing the importance of Nedd4-2 expression in regulating neurite outgrowth in PC12 cells. Studies presented here indicate that Nedd4-2 acts to negatively regulate neurite development in PC12 cells, furthermore it is demonstrated that neurogenic proteins such as NGF and Ras differentially regulate Nedd4-2. This work was extended into an in vivo model, made possible by the generation of Nedd4-2 knockout mice. These studies demonstrated the importance of Nedd4-2 in maintaining homeostasis, indicating that complete abrogation of Nedd4-2 expression is peri-natal lethal. Histological assessment of key brain regions developing at this time indicates that the absence of Nedd4-2 is accompanied by deranged development of cortical areas in the brain. To gain insight into molecular mechanisms that mediate the phenotype observed in both the in vitro and in vivo modelling of Nedd4-2 during development an in silico screen was performed to develop a definitive list of putative binding candidates, this revealed the extent of the potential role for Nedd4-2 in regulating biological processes. Most notably, it was shown that PY containing proteins are enriched in pathways that regulate axon guidance receptors and the cytoskeleton. Of this list, it was demonstrated for the first time that Nedd4-2 binds to the axon guidance receptor, Neogenin and that Neogenin is ubiquitinated most likely in a Nedd4-2 dependent manner, highlighting the importance of Nedd4-2 in regulating the cell surface expression of proteins. Furthermore, prediction of the Nedd4-2 interactome led to the identification and characterization of MAP2 as a novel Nedd4-2 binding protein. These studies gave rise to the novel observation that Nedd4-2 is a potent regulator of the neuronally expressed MAP2 and indicate that Nedd4-2 can effect the differentiation and branching behaviour of nascent neurons possibly through destabilization of tubulin polymerization. Taken together this thesis demonstrates that Nedd4-2 is an important negative or rate-limiting regulator of neuronal differentiation and development in the embryonic brain, dorsal root ganglia and in PC12 cells. Furthermore, it is suggested that ubiquitin-mediated regulation of Nedd4-2 ligands such as MAP2 and Neogenin may be the effectors of the phenotype observed in the Nedd4- 2 knockout mice. This thesis also contributes to the broader understanding of how complex and convergent signalling networks are discretely regulated to achieve proper development and homeostasis.

The Role of Tissue Inhibitor of Metalloproteinases-3 (TIMP-3) in Haematopoiesis

Yi Shen — 2011-03-23T00:00:00Z

Haematopoietic stem cells (HSC) give rise to haematopoietic progenitor cells (HPC) which terminally differentiate into all blood cell types. HSC can reconstitute the haematopoietic system following damage and reside in specific micro-domains of the bone marrow (BM) known as niches. HSC niches are preferentially located at the interface between the bone and BM (endosteum) and are abundant in long bones. Molecules expressed in these niches provide the extrinsic cues that control HSC quiescence, self-renewal or differentiation by asymmetric division. Many proteins found in these niches are involved in the egress of HSC into the blood during mobilisation. These proteins include proteases such as neutrophil elastase, cathepsin-G and matrix metalloproteinases (MMP), as well as their inhibitors, α1-antitrypsin (serpina1) and tissue inhibitor of metalloproteinases (TIMP)-1 to -4. TIMP-3 is a less studied member of the TIMP family. It not only regulates MMP activity but also the activity of sheddases (and thus plays a role in cytokine maturation), prevents vascular endothelial growth factor binding to its receptor 2, inhibits cancer proliferation and can cause sorsby fundus dystrophy. Despite its many interesting functions, TIMP-3’s role in haematopoiesis and mobilisation has not been well documented. By qRT-PCR and reverse zymography, I have determined that TIMP-3 mRNA is expressed at a 10-fold higher level at the endosteum when compared to central BM. Multipotent stromal cells (MSC), endothelial cells and mature osteoblasts (OB) expressed high levels of TIMP-3. Erythroid progenitors, megakaryocyte progenitors and mature megakaryocytes expressed TIMP-3 mRNA at much lower levels than stromal cells, while all other haematopoietic cells expressed extremely low to undetectable levels of TIMP-3 mRNA. Immunohistofluorescence on paraffin embedded bone sections with a rabbit anti-human TIMP-3 antibody (which cross-reacts with mouse TIMP-3) validated TIMP-3 protein expression in endothelial cells, OB and megakaryocytes. Interestingly, TIMP-3 mRNA and protein expression decreased with granulocyte-colony stimulating factor induced mobilisation. To investigate TIMP-3 function, human TIMP-3 (huTIMP-3) cDNA was over-expressed in mouse HSC via retroviral transduction using MND-X-IRES-eGFP (MXIE) retroviral vector. In mice transplanted with HSC transduced with MXIE retroviral vector containing huTIMP-3 cDNA, the frequency of B-cells and T-cells over-expressing huTIMP-3 were significantly reduced in blood and BM when compared to mice transplanted with HSC transduced with control empty vector. Conversely, the frequency of huTIMP-3 expressing myeloid cells was significantly higher in the blood, BM and spleen. Blood leukocytes and splenocytes of mice over-expressing huTIMP-3 in haematopoietic cells exhibited significantly greater colony forming ability. The presence of huTIMP-3 also increased Lineage-Sca-1+Kit+ stem cell proliferation both in vivo and in vitro. Interestingly as well, long term over-expression of huTIMP-3 resulted in calcification of bones with markedly decreased BM content and ultimately death.

The role of trust in community acceptance of urban water management schemes: A social-psychological model of the characteristics and determinants of trust and acceptance

Victoria Ross — 2010-06-04T00:00:00Z

Given the important role that trust plays in acceptance of water management schemes, the current research investigated the characteristics and determinants of trust by developing a social-psychological model of trust in the area of water management and reuse. The research advanced a theoretical understanding of trust by using social identity theory and the relational model of trust as a framework and providing a systematic examination of the relationships between the variables in the hypothesised trust model. The proposed trust model was tested across three potentially different perceived risk contexts; low, medium and high. Analysis through path modelling provided strong support for the hypothesised model. In all three contexts trust in the water authority was a significant predictor of acceptance of the water management scheme, and risk perceptions mediated the relationship between trust and acceptance. In other words higher levels of trust in the authority were associated with lower perceptions of risk, which were in turn associated with higher levels of acceptance. In Study 4, which was set in the high perceived risk context of the proposed indirect potable reuse scheme in Toowoomba, perceptions of risk had the strongest direct effect on acceptance of the scheme, and the trust, risk and acceptance relationship was stronger than it was in the other studies. The relational variables of procedural fairness, identification with one’s community, ingroup membership of the water authority and a social bond (shared values) with the water authority were all found to impact on trust, either directly or indirectly. In addition, the instrumental variable of the credibility of the authority (measured as technical competence and a lack of vested interests) was found to have a significant impact on trust. Taken together, the results provide support for social identity theory and the relational model of trust as a framework for understanding trust in authorities. The results are also consistent with literature that suggests that the relational and instrumental models of trust are not incompatible (e.g., Edwards & Kidd, 2003; Tyler & Kramer, 1996). The findings from this research program clearly have a practical application for improving acceptance of water management schemes. The combined results demonstrate the importance of trust in the water authority in reducing perceived risk and thus increasing acceptance of schemes. The results highlight the need for water authorities and policy makers to build public trust through procedural fairness, building a sense of the water authority as a member of the community, and through demonstrating technical competence and concern for the interests of the public.

The Role of Ultraviolet Radiation in Molecular Pathways to Melanoma

Hacker, Elke — 2008-11-21T00:00:00Z

A great deal of cancer research is aimed at describing the precise mechanisms that allow cells to become transformed. Many genes have been associated with melanoma and the majority of the functions of these genes pertain to three pathways Ras/Raf/MAPK, Ink4a/Cdk4-cyclin/pRb and ARF/Mdm2/p53. Over-expression of Hras in melanocytes, combined with a single neonatal UVR dose is sufficient to induce melanoma in pigmented mice. These lesions were small in situ cutaneous melanomas. To assess the role of the pRb pathway in melanoma mice, over expressing Hras were combined with activated Cdk4 mutants. These animals develop melanoma spontaneously, with a penetrance of 58%, which rose to 83% after neonatal ultraviolet radiation (UVR). Furthermore, the entire UVRtreated cohort that developed melanoma had multiple cutaneous lesions and 92% had metastatic tumours. In this model Hras activation alone is sufficient to predispose melanocytes to UVR-induced transformation, while mutant Cdk4 is more important for tumour progression, producing larger more aggressive, metastatic melanomas. To further assess the Ink4a/Cdk4-cyclin/pRb pathway in this disease a melanocytespecific deletion of the Rb1 gene was constructed. This model allowed for the culturing of Rb1-null melanocytes. Rb1-null melanocytes were studied and found to proliferate more rapidly than controls and to have a decreased requirement for mitogens. Expression arrays were performed to identify differences between the small in situ TPras lesions and those more aggressive Cdk4[superscript]R24C/R24C/TPras melanomas. We observed up regulation of Tcfeb, Ednrb, Tcfap2b and Gpr155 and down regulation of Plagl1 in Cdk4[superscript]R24C/R24C/TPras lesions. The overlay of expression and aCGH analysis showed dysfunction of various genes that are involved in regulating p53 and DNA repair pathways in the Cdk4[superscript]R24C/R24C/TPras tumours (Plagl1, Abcc10, Hsp90aa1 and Htatip). We also observed aberrations of several genes that regulate p21 (E2F2 and Htatip) and identified several potential markers of melanoma progression (Pax7, Dpp3, cdc42, Fgf22, Nme2, Esm1, Ednrb, Mum1 and Notch4). We also identified several genetic changes in Cdk4[superscript]R24C/R24C/TPras tumours that were specific to either UVR-induced or spontaneously derived lesions and identified a number of candidate genes (Hsp90aa1, Gzmk, Esm1, Bop1, Rapgef3, Htatip and Dpp3). This study has identified numerous novel candidate genes and also confirmed the importance of various melanoma-associated genes in this disease.

THE ROLE OF UNPLANNED HUMAN SETTLEMENTS IN LAND COVER CHANGE: A CASE STUDY OF THE CHYULU HILLS SQUATTERS- KENYA

Grace Muriuki — 2011-03-21T00:00:00Z

Investigations in this thesis advance our understanding on the role of unplanned human settlements in land cover change. Despite its complexity, the fundamental causes of land cover change are well known, and comprise biophysical, economic, policy/institutional and demographic factors. Of these, population growth and migration are implicated as the most significant. In future almost all land cover change will occur in rural areas which are experiencing rapid increases in population and migration, already a critical concern for conservation programs worldwide. Squatters are immigrants who illegally establish residence in areas deemed unsettled or with poorly-defined tenure. Their land use decisions tend to be risk-minimization strategies, influenced by their socio-economic characteristics and lack of long-term stakes in the land they occupy. This reduces their motivation to invest in and conserve resources, and they often become exceptional land degraders. In order to reduce their impact on landscapes and minimise the conflicts associated with their settlements, there is need for targeted research on their role in land cover change. I contribute knowledge to this problem using the Chyulu Hills as a case study. First, I reviewed current knowledge on migration and land cover change and the influential structural constructs that guide research in this field. Based on this review, I evaluated the dynamics of squatter migration to the Chyulu Hills, and the history of conflicts of squatters with the protected areas. Combining community surveys with statistical analysis, I revealed the proximate and underlying causes of the migration. I found that squatter movements to Chyulu Hills were widespread and long term, and that squatters are drawn from all over Kenya. Household socioeconomic and policy-related factors such as provision of schools, land tenure security and issuance of free land had a strong influence on squatter migration. Land and settlement policies were also implicated in migration and squatting. Most significantly, I established a high prevalence of secondary migration, where squatters migrated repeatedly to maximise their livelihood opportunities. The responsiveness of squatters to policy stimuli highlighted its potential to regulate or influence squatter mobility in rural landscapes. Next, I combined remote sensing/GIS tools, community surveys and landscape metrics to evaluate the rates and patterns of land cover change in the Chyulu Hills between 1967 and 1999, a period of high squatter migration. I found rapid changes in land cover over the 32 years of squatter settlements. The total proportion of native vegetation (dense forests, open forests and shrublands) decreased from 91% to 36%. In the same period, dense forests declined by 8.7% while cultivation expanded by approximately 40%. I explained these changes in the context of policy and management of land and the protected areas of Tsavo and Chyulu Hills. Squatter problems were related to land alienation during the British colonization of Kenya. I found preferential patterns of village establishment in or near dense forests. Landscape fragmentation confirmed the spontaneous nature of squatter settlements, and it is not clear yet how these transformations might affect the wildlife that uses it as a dispersal area. The community knowledge of the patterns and processes of land cover change, assessed using an adapted semi-quantitative tool known as proportional piling, agreed well with quantitative GIS measures of land cover change. Following this, I tested alternative postulates of the role of biophysical, household socioeconomic, access and institutional factors in the variation in remnant vegetation in villages in Chyulu Hills. Using Generalised Linear Models, model averaging and hierarchical partitioning analyses, I selected the best set of models within a 95% confidence interval, and ranked the relative importance of the explanatory factors in the variation in remnant vegetation. I found that squatter presence and their associated characteristics of short stays in villages, larger households and younger household heads were the most significant factors in remnant vegetation variations. This was supported by results of hierarchical partitioning. I then analyzed the policy on management of squatters and protected areas. For the most part, squatter management is ad hoc and reactionary, biased towards urban squatters, and largely limited to site and services improvements. I argued that this arose from a multiplicity of governance institutions and policies for natural resource management with overlapping mandates, rigid conservation management paradigms, and lack of provisions for participatory engagement of all stakeholders. I proposed the promotion of enabling policy environments that embrace participatory opportunities supported by building squatter human and social capital. Long-term land use planning should consider alternative livelihood sources that are less dependent on land as viable opportunities for reducing landscape changes and conflicts associated with squatters in rural areas. I recommend further research that integrates a broader spectrum of exogenous and contextual factors such as national policies, droughts and pandemics such as HIV/AIDS that influence household socioeconomics in rural land cover change. I also propose predictive studies that build potential future scenarios and that utilise finer temporal and spatial resolutions.

The "rules of engagement": Social conventions surrounding the communication of criticism

Carla Jeffries — 2012-04-27T00:00:00Z

Criticism is important because it carries the potential for growth and positive change. Criticism holds the potential to identify weaknesses and suboptimal behaviours and, if acknowledged and integrated, can lead to the positive transformation of an individual or a group. Despite the therapeutic benefits of criticism, communicating critical feedback is a difficult behaviour. Criticism is frequently experienced as threatening and, when delivered or “taken” badly, can lead to a cascade of negative consequences (damaged self-esteem, hurt, conflict, withdrawal). Because it carries so much potential for hurt, the delivery of negative feedback is bounded by complex codes of etiquette. The present thesis aims to provide the first comprehensive map of these “rules of engagement” and to explore their psychological underpinnings and consequences. Chapter 2 describes the extant literature pertaining to the communication of interpersonal criticism. It then presents a survey study (N = 849) examining the extent to which people view the communication of criticism as more or less appropriate across various targets and in various contexts. We found evidence that respondents calibrate their feedback as a function of (a) the psychological resilience of the target, (b) whether the target is mutable, (c) whether the target deserves punishment, and (d) whether the target lies outside or within the boundary of one’s extended self. The effects are robust across age and gender. Cross-cultural differences in the endorsement of some rules were identified. Chapter 3 presents a study (N = 263) that disentangles the extent to which the withholding of negative feedback is motivated by a desire to protect the self as opposed to a desire to protect the target from the damaging social consequences of criticism. We found that participants provided more negative essay feedback if they thought that their assessments were anonymous than if they anticipated providing feedback face-to-face with the essay writer. Feedback was most negative when the feedback was not to be delivered to the essay writer at all. This effect only emerged among participants who were low in self-liking (but was unrelated to perceptions of self-competency). Manipulations of the self-esteem of the essay writer had no effect at all on evaluations. The data lend strong support for a self-protection motive and more modest support for an other-protection motive for withholding negative feedback. Chapter 4 presents two studies investigating the normative protection of low status groups from criticism. Study 1 (N = 816) identified the “David and Goliath” rule – the tendency for people to perceive members of “David” groups (groups with low power or status) as more “off-limits” to criticism than “Goliath” groups (groups with high power or status). We identified the existence of the David and Goliath rule across five national samples (Study 1). However the rule was endorsed more strongly in Western than in Chinese cultures, an effect mediated by cultural differences in power distance. Study 2 (N = 302) identified the psychological underpinnings of this rule in an Australian sample. Lower social dominance orientation (SDO; Pratto, Sidanius, Stallworth, & Malle, 1994) was associated with greater endorsement of the rule, an effect mediated through the differential attribution of stereotypes. Specifically, those low in SDO were more likely to attribute traits of warmth and incompetence to David versus Goliath groups, a pattern of stereotypes that was related to the protection of David groups from criticism. In Chapter 5, three studies investigated whether men and women are viewed as more or less appropriate to criticize. In Studies 1 (N = 502) and 2 (N = 129) we identified the tendency for people in both community and student samples to view women as more “off-limits” to criticism than men; coined the gender rule. This effect was moderated by participant gender with male participants endorsing the gender rule to a greater extent than female participants. Study 3 (N = 163) demonstrated that the gender rule is not a broad brush tendency with all women receiving protection from criticism. Consistent with work on stereotype content, both male and female targets occupying communal roles (high warmth-low competence) received less negative feedback than male and female targets in agentic roles (low warmth-high competence). These differences in performance evaluations could not be explained by differences in performance expectations or endorsement of benevolent or hostile sexism. In sum, this thesis demonstrates that there are rules that govern the delivery of criticism. We argue that the ironic consequence of “protecting” certain individuals and groups against criticism is that these people and groups are not given the same opportunities to learn and grow from their mistakes. The potential for miscommunication – and the perverse implications of withholding criticism – are discussed in Chapter 6.

The Science and Policy of Greenhouse Gas Management: A study of Australian and British stakeholder understanding, demands and expectations within the anthropogenic climate change discourse

Graham Farebrother — 2011-11-15T00:00:00Z

This study examines the science and policy interactions of greenhouse gas management (GHG) in Australia and the UK. It takes an historic approach, detailing how human recognition of Earth System impacts developed. As perturbations to different aspects of the Earth System were increasingly recognised, concerns grew for the sustainability of the natural world, and consequently for the sustainability of the economic system that underpins human societies. Over time, impacts and problems of increasing complexity have been identified, and it has become evident that an ad hoc manner of economic advance cannot be perpetuated. Much global and nation state effort is currently dedicated to designing and implementing policies to mitigate and manage the expected far-reaching impacts associated with anthropogenic climate change (ACC). The ACC discourse has progressed rapidly in recent times. Speculation of human interference in the Earth’s climate began in the 19th century; this speculation progressed into warnings in the 1930s, followed by quantitative measurements of atmospheric perturbation in the 1950s. Fears of anthropogenic disruption to the Earth System in the form of climate change have since resulted in international agreements, underpinned by concepts of sustainable development, and the precautionary principle. During the second half of the 20th century, civil society grew in strength and adopted a more powerful role in decision making processes and governance within many nation states; a process that has been actively encouraged through the activities of the United Nations. This change, in conjunction with a growing Green ethic, driven by the observation of environmental damage and impacts, has enveloped many aspects of human activity. As the level of industrialisation has increased in both scope and geographic range, environmental impacts have grown from local to regional to global and, with the onset of predictive computer modelling, bleak scenarios of future conditions have ensued. A growing knowledge base pertaining to various aspects of ACC has merged with both the expectations of an increasingly more powerful civil society, and an increasingly pervasive Green ethic. Following the introduction of the United Nations Framework Convention on Climate Change in 1992, GHG management has been at the fore of global and nation state policy discussions. The ACC discourse has since become increasingly embroiled with issues of sustainability; equity between developed and developing countries; and, the maintenance and promotion of the economic positions of various developed countries and trading blocs. Because of the broad association of GHGs with a variety of human activities, the discourse is seen by many as an umbrella cause. The goal of reducing anthropogenic GHG perturbation of the atmosphere has been coopted to heighten the awareness of many environmental and social problems, and to underpin the promotion of a range of vested interests. To understand the role of science in the development of GHG management policies, this study examines stakeholder understanding, perceptions, and expectations of both climate change science and mitigation policies. Interviews conducted in the UK and Australia, that targeted vocal and affected stakeholders, suggested that a high level of expectation is associated with the outcomes of GHG management policies; beyond the direct minimisation of climate interference, other environmental and societal improvements are expected. The ACC discourse is associated with a broad swath of issues that are found within contemporary society and deemed to be in need of resolution. The discourse is not only linked to existing and well known issues such as tropical rainforest deforestation, developing country poverty alleviation, biodiversity decline, and waste management but also to emerging problems including resource decline, rampant consumerism, falling human health standards, environmental degradation, and low levels of societal wellbeing. These associations are shown to be strong even when stakeholders have limited knowledge of, or even regard for, the underlying science of ACC. As a consequence of these many and varied associations, that have different sets of emphases from different elements of civil society, and in different locations, instigating universally acceptable GHG management policy is suggested as being problematic. Findings from this research suggest that if a greater focus on quantifiable environmental and societal improvement was a component of localised GHG management policies, then their acceptance and uptake by civil society would be eased and enhanced. The study shows that many less than ideal conditions and norms have developed within different societies and that a focal point is widely recognised as being useful or even necessary to help identify and rectify such problems. At both local and global levels, because of its direct association with Earth System impacts and the links to unsustainable forms of human behaviour, GHG management could be such a focal point if it is appropriately used.

The search for meaning in music education: Reflections on difference and practice.

Cuskelly, James Martin — 2008-11-21T00:00:00Z

This thesis investigates issues of meaning in music and the ways in which music education can be organised and delivered to maximise the experience of meaning for students. Two key questions are pursued within this thesis. Firstly, what is the nature of meaning in music, both as it is reported by educators and students, and evidenced in the literature? Secondly, in what ways can music education curriculum be organised to maximise this experience of meaning for students, specifically in the core areas of listening, composing and performing? In recognizing the various ways in which concepts of musical meaning are employed within music education and in an attempt to clarify and more accurately define what is intended when referring to meaning in music, three specific terms-signification, responsification and socialification-are suggested. The use of these terms also provides important points of reference throughout the discussion. Employing an autobiographical and phenomenological approach alongside a critical analysis of music education philosophies, this study investigates the lived experiences of teachers and students in terms of meaning in music. The inclusion of personal histories-my own and the stories of the students whom I teach-within the methodological framework provides a unique vehicle for the capture of data given the highly personalised nature of much of the material to hand. Further, a consideration of the lived experience of teachers and students in light of contemporary research and thinking serves to firmly anchor the discussion within the educational context. This research has found that issues of meaning are layered, multifaceted and interrelated, that there are numerous elements that contribute to meaning and that what is significant in music may be diverse, varying from individual to individual, from group to group. Musical meaning may be highly personalized and /or culturally delineated, and meaning in music may not remain static; it may vary across experiences or over time. This research has identified particular practices and approaches which significantly influence the development of meaning in music; such educative practices are worthy of sustained consideration by those within the field.

THE SELF EVALUATION MAINTENANCE MODEL IN ADOLESCENT SIBLING AND TWIN RELATIONSHIPS

Blakeley-Smith, Anita Maria — 2008-11-21T00:00:00Z

The project was designed to examine how nontwin and twin sibling adolescents deal with situations of competition and comparison between them. Using the Self Evaluation Maintenance Model (Tesser, 1988) as a framework, this project explored the reactions and strategies that adolescent nontwin and twin adolescents employ in order to maintain a positive selfevaluation. In addition, the potential mediating factors of sibling relationship quality and perceptions of differential parental treatment on adolescents reactions to competition and comparison to their self esteem was also investigated. Three studies were conducted. All three studies investigated the relevance of the SEM model to understanding nontwin and twin adolescents reactions to situations of competition and comparison, but employed different methodologies and samples. Study 1 involved both members of the sibling pair completing a questionnaire that included their emotional and behavioural reactions to selfgenerated situations of competition and comparison, counterbalanced by closeness, relevance and performance. In this study, closeness referred to either a sibling or friend comparator. Four hundred and sixty (232 pairs of) same sex nontwin and twin adolescents aged between 13 and 17 took part in Study 1. The results revealed that both sibling nontwin and twin adolescents were motivated to maintain a positive self evaluation. In line with the SEM model, both the comparison and reflection processes were evident for emotional reactions. However, closeness of the competitor did not interact with selfrelevance of the task to affect performance as predicted. Self evaluation was enhanced when both nontwin and twin adolescents were outperformed on tasks of low rather than high self relevance, indicating the presence of the reflection process. However, nontwin adolescents reported being more positive about being outperformed by their sibling than their friend suggesting that siblings may consider their friendships to be the closer relationship to them. Closeness of the competitor did not affect positive reactions to competition and comparison for twin adolescents. For negative emotional reactions and behavioural reactions, closeness of the competitor did not interact with relevance to affect performance for either nontwin or twin adolescents as predicted. Birth order was found to affect self evaluation, even in twin relationships. Both younger nontwin and twin adolescents were more able to preserve self evaluation when outperformed by their older sibling, while older nontwin and twin adolescents found being outperformed by their younger sibling to be particularly difficult. Zygosity effects were only found for positive but not negative emotional reactions. Contrary to expectations, perceptions of differential parental treatment did not mediate emotional reactions to self esteem for adolescents. Sibling relationship quality did not mediate emotional reactions to self esteem for nontwin adolescents. When outperformed by their twin, sibling relationship conflict and sibling relationship warmth was found to mediate emotional reactions to self esteem for monozygotic twins and dizygotic twins respectively. A subsample of Study 1 participants completed Study 2. The participants in Study 2 were one hundred and six (53 pairs of) nontwin and twin same sex adolescents. Study 2 explored nontwin and twin adolescent siblings emotional reactions to situations of competition and comparison in an experiential context, again using the SEM model (Tesser, 1988) as a framework. Sibling pairs were asked to orally discuss situations where they had competed with or compared themselves to their sibling/twin, to view themselves completing this discussion and then to complete a series of questions relating to Tessers (1988) SEM model. Subjects completed the same questions for each of the four SEM conditions, counterbalanced by performance on the task and relevance of the task. As adolescents only competed against a close competitor (i.e. their sibling), the relevance of the task was the determining factor as to whether the processes of reflection and comparison would be utilised. The comparison and reflection processes were indicated for both positive and negative emotional reactions for nontwin and twin adolescents. Unlike Study 1, birth order, zygosity effects and mediating effects of sibling relationship quality were not found. Study 3 involved comparison of nontwin and twin adolescents in terms of self evaluation maintenance within the framework of the SEM model in both the retrospective and experiential context. In this study, closeness was assessed in terms of genetic similarity. Monozygotic twins showed the most positive emotional reactions to performance against their twin than dizygotic twins and siblings in both contexts. For retrospectively recalled situations, siblings, rather than twins, reported the most negative reactions to being outperformed on highly self relevant tasks compared to monozygotic and dizygotic twins. This project found that the SEM model (Tesser, 1988) provided a more valid framework for explaining both twin and nontwin adolescent siblings self evaluation maintenance than a strictly social comparison approach. The results of all three studies were interpreted as being generally consistent with the SEM model. The results contribute new insights into differences in self evaluation maintenance between nontwin and twin adolescent siblings and provide direction for future research into the potential role of birth order, sibling relationship quality and attachment in adolescents self evaluation maintenance.

The sensory biology and feeding behaviour of sawfish

Barbara Wueringer — 2011-04-13T00:00:00Z

The family of pristid sawfish face a global crisis, with all species listed as critically endangered on the IUCN Redlist. One characteristic that all species have in common may also be a major factor contributing to their decline; the elongated rostrum that bears lateral teeth (the ‘saw’). As the saw becomes easily entangled in fishing gear and is also a valuable trophy, sawfish are regularly taken as by-catch. However, the use of the saw has never been studied. My objective is to identify the importance of the saw during prey manipulation, and to assess the relative importance of three sensory modalities (vision, electroreception and mechanoreception) in the same context. The morphology of the rostrum of pristid sawfish was analysed and compared to rhinobatid shovelnose rays and the extinct sclerorhynchid sawfish, as these three families are monophyletic. Comparison of the internal structure of the rostrum in the three taxa indicates that in pristids the anterior portion of the rostrum lengthened, which results in a slimmer construction than that of the sclerorhynchid rostrum. Moreover, pristid rostral teeth grow continuously from the base, whereas sclerorhynchids possess functional rostral teeth and dormant replacement teeth. Characteristics of the pristid rostrum are interpreted as adaptations to reduce weight and therefore potentially allow fast lateral swipes of the rostrum during food manipulation. Contrary to other batoids, the atlanto-occipital joint of pristids allows free movement of the cranium in all directions. Feeding observations of juvenile freshwater sawfish Pristis microdon lead to the establishment of an ethogram in the context of prey manipulation. Results indicate that an average feeding event that leads to the successful ingestion of a fish is comprised of five behaviours, of which at least one includes the use of the saw. However, freshwater sawfish use their saw during prey manipulation in three distinctive behaviours. Comparison of the two dimensional sensory array of the electroreceptive ampullae of Lorenzini in rhinobatids and pristids reveals how the elongation of the rostrum may have expanded the food spectrum of pristids: the total number of ampullary pores distributed ventrally on the head and rostrum of the pristid Anoxypristis cuspidata (490.3 ± 68.7) equals that of the rhinobatids Glaucostegus typus (452.0 ± 162.8) and Aptychotrema rostrata (461.5 ± 17.7). However, A. cuspidata possesses more than seven times the number of pores on the dorsal surface of the rostrum (297.1 ± 56.6 pores) than the rhinobatids (A. rostrata 40.7 ± 2.3 pores, G. typus 24.9 ± 5.1 pores), indicating that pristids can potentially sense the electric field of prey in the water column. One retina of a juvenile freshwater sawfish P. microdon was analysed in a retinal wholemount. The density distribution of photoreceptors shows several peaks mediating acute vision, which is comparable to the retina of a white tip reef shark Triaenodon obseus. These peaks may help sawfish to maneouvre structurally complex habitats, such as mangrove roots in rivers in order to hide from predators. Peaks in the rod and cone density of the temporal region may be useful during prey manipulation with the rostrum. Detailed knowledge of sawfish biology is crucial for maintaining optimal health of these endangered species in captivity and alleviating future fishing pressure.

THE SILENCING OF DISSENT IN THE AUSTRALIAN JEWISH COMMUNITY

Salom, Margot F. — 2008-11-21T00:00:00Z

This thesis explores the experiences of Jewish peace activists in Sydney, Australia, who actively dissent from the mainstream Jewish community by expressing criticism of the oppression of the Palestinian people by various Israeli governments. Although some literature from the United States addresses the phenomenon of the silencing of dissent in the Jewish community, to date there has been very little research interest in the subject of dissent in the Australian Jewish community. This study sought to investigate the issue of dissent in the Australian Jewish community by examining the experiences of Jewish peace activists within an ethno-religious mainstream. Respondents were drawn from two Jewish peace groups in the Sydney metropolitan area. Data was generated by means of a questionnaire, which was sent to potential respondents at the time of the initial selection process. A series of semistructured, in-depth interviews followed, based on those questions and subsequent responses. The findings reveal that peace activists included in this research feel that there exists a subtle expectation/constraint within the Jewish community that disallows criticism of the Israeli government. Indeed, the majority of respondents revealed that they have personally experienced some form of silencing of their opinions and the majority of respondents either keep silent or avoid situations that would expose their views. This research also examines how Jewish peace activists perceive their identification as Jews in view of the attempts to silence their dissenting views. A majority of those interviewed agreed that they regard their activism as an expression of their Jewish identity and that they link their political stance with Jewish ethics related to justice and human rights.

The Sintering Behaviour of Al-Mg-Si-Cu-(Sn) Powder Metallurgy Alloys

Enda Crossin — 2010-03-01T00:00:00Z

The current, commercially available, press and sinter Al-Mg-Si-Cu alloys are based on wrought or cast alloy compositions and have not been tailored for the press and sinter process. The limited development of the Al-Mg-Si-Cu alloys for the press and sinter process can be partly attributed to a poor understanding of the effects of processing conditions on the sintering behaviour. The primary objective of this work was to investigate and understand the effects of processing conditions on the sintering behaviour of Al-Mg-Si-Cu-(Sn) alloys. Dilatometry was used in conjunction with other experimental techniques to elucidate and understand the expansion and shrinkage events that occur during the liquid-phase sintering of Al-Mg-Si-Cu-(Sn) powder metallurgy alloys. Samples were uni-axially pressed from elemental metal powder blends, de-waxed, and then sintered in a horizontal push-rod dilatometer to record the dimensional changes in the pressing direction. The processing conditions examined included the alloy composition, temperature, green density and atmosphere. A liquid forms during heating due to reactions between the alloying elements and the aluminium. This liquid is initially non-wetting on the oxide layer of the aluminium particles, resulting in separation of the particles, which is manifested by expansion of the sample. The oxide is reduced as sintering progresses, alleviating the non-wetting conditions. When more liquid forms, further expansion occurs, despite the improved wetting conditions. It is proposed that atmospheric oxygen and/or nitrogen can react with the liquid, forming a solid phase (‘shell’) at the liquid-vapour interfaces. These shells prevent the liquid from wetting the particles, resulting in further expansion and preventing shrinkage. Unbalanced diffusivities (the Kirkendall effect) between the aluminium and silicon contribute to the expansion. A mechanism is proposed to account for the transition to shrinkage, whereby the shells at the liquid-vapour interface rupture when there is a rapid increase in the volume of contained liquid. The liquid then flows out and over the shells, onto the aluminium substrate, causing shrinkage. Magnesium and nitrogen delay the transition to shrinkage by facilitating nitride shell formation at the solid-liquid interface. Silicon and tin cause an earlier transition to shrinkage by increasing the liquid volume. In addition, tin promotes shrinkage by segregating to the liquid-vapour interfaces, limiting the thickness of the shells at the liquid-vapour interfaces. The two dominant liquid-phase shrinkage mechanisms during the sintering of Al-Mg-Si-Cu-(Sn) alloys are rearrangement and pore-filling. Contact-flattening is not a dominant shrinkage mechanism, but may occur concurrently with the other mechanisms. If contact flattening occurs, a decrease in the pressure of isolated pores increases the total shrinkage rate. Nitrogen increases the shrinkage rate during rearrangement by restricting grain-growth. Magnesium increases the shrinkage rate during rearrangement by reducing the solid-liquid interface energy. Magnesium and nitrogen are essential for the formation of nitride within isolated pores, which decreases the pore pressure and increases the contribution of contact-flattening on the total shrinkage rate. Silicon reduces the beneficial influence of magnesium during rearrangement by diluting the magnesium content in the liquid. Silicon increases the pore-filling rate due to an increase in the liquid volume. Magnesium increases the pore-filling rate by facilitating aluminium nitride formation within isolated pores and by increasing the pore-filling. Tin additions can decrease the pore-filling rate due to its segregation to the liquid-vapour interface, limiting the consumption of nitrogen within isolated pores.

The social construction of economic man : the genesis, spread, impact and institutionalisation of economic ideas

MacKinnon, Lauchlan A.K. — 2008-11-21T00:00:00Z

The social context of familial child sexual abuse: the mother's perspective

Porter, Janet — 2008-11-21T00:00:00Z

This thesis examines the experiences of mothers whose children have been sexually abused by a male adult family member. It explores the relationships between the effect of biographical and social factors on mothers' perceptions and their experiences on learning of their children's sexual abuse. It also includes interrelated aims: a)to identify implications from the research for the development and extension of qualitative research methodology, and b)to develop and extend the understanding of the mothers' role in the sexually abusive situation. The mothers' perspectives and how they experienced the phenomenon of the sexual abuse of their child are central to the study. Historically the mother has been marginal to empirically based research while central to explanations regarding the causes and responsibility for the sexually abusive situation. Increasingly as the extent of sexual abuse as a social problem has been realised, the mother's role has been seen as central in the support of her children after the disclosure. In the literature, however, the lack of empirical research relating to the mother's experiences results in adherence to general prescriptive knowledges about motherhood. The primacy of the mothers' narratives in this study is therefore emphasised. Thirty mothers participated in the study and were a self selecting sample. They were contacted through social workers, self referral through other participants, and a private agency. The study combined quantitative and qualitative approaches. Quantitative approaches allowed the collection of socio-economic, demographic data and characteristics of the sexually abusive situation. This data was used to compare findings within and between cases and between this study and others reported in the literature. The interview guide was used as a prompt sheet rather than a structure of the interview process. The interview data contained the mothers' perceptions of their life experiences and how these affected their responses and reactions to events and relationships before and after disclosure of the abuse. This study, however, differed from much of the previous research in using qualitative approaches and in encouraging mothers to discuss what was of importance to them. The focus throughout the study was on the mothers' subjective realities and how they changed over time, as they attempted to make sense of their role in the establishment and maintenance of the abusive situation. The mothers were able to report their experiences in their own way, and were able to make their own links between ideas and perceptions which were not structured by the research process. The thirty transcripts were sorted and analysed using NUD*IST, a computer software programme for manageing non numerical, unstructured data. From the mothers' narratives four regularities and processes were noted: childhood socialisation in the family of origin, courtship and marriage, relationship to the abuser, and the disclosure of the abuse. Within each of these regularities and processes, similarities and differences were identified in relation to a number of themes and sub themes as the mothers reconstructed their experiences. The study focuses on how they experienced: the disclosure process; their relationship to the abuser, the child and perception of the abuser/child relationship; and who caused and was responsible for the perpetration of the abuse. The mothers' life experiences within different family and social contexts impacted on them in various ways. All the mothers contended, however, that for the abuser to sexually abuse the child in secret required not only the manipulation of the child but also the manipulation of others in the family and social environment. The primacy given to the mothers' experiences gives an alternative perspective to the understanding of the environments and processes involved in the maintenance and establishment of the sexually abusive situation and the mothers' role. Their accounts are local, contextualised and grounded in their life experiences. Their experiences are used as a basis for a critical analysis of family systems theory. A tentative theoretical development has also been presented using concepts from chaos theory and Foucault in a heuristic way. This study has implications for workers in the areas of investigation and therapeutic intervention. The mothers' perspectives challenge views presented in the literature about the culpability or powerlessness of the mother. Their experiences of the sexually abusive environment and processes involved, give insight into the manipulative and controlling strategies of the abusers. While the findings have limited generalisability, the methodological approach, analytical processes and extension of the theoretical understanding could be applied to other areas of social science research.

The sociality of healing Engaging Southern Sudanese refugees resettling in an Australian context a model of social healing

Westoby, Peter Ralph — 2008-11-21T00:00:00Z

Within the thesis the author examines how Southern Sudanese refugees understand healing as a social process in a resettlement context within Australia. This examination has led the author to explore first how do we understand the distress of refugees, and second, what are the social processes that facilitate healing? The author builds on the argument that if healing is at least partly a social process then the re-building of a social world for refugees is critical for recovery. Social healing is the metaphor used as a way of describing this process and a new model of intervention. The key argument of the dissertation is that contrary to much of the literature, the distress exhibited by Sudanese refugees is related more to resettlement issues than to the experiences of violence that caused their refugee status. Broadly speaking, their distress is located in the social milieu of their resettlement. It follows from this that the primary goal of intervention should be based on a model of the social that is developed in this thesis. This model differs from current intervention models in two principle ways: (i) instead of being therapeutically oriented to the individual, it requires the identification of social healing across three spheres of culture, community and power; and (ii) rather than focusing on the professional/ client relationship, intervention needs to be dialogically based on the agency of the Southern Sudanese communitys attempt to make sense of their agonistic new location in Australia. The analysis is used to tentatively theorize social healing. The author also aims to build an archive of the subjective experience of refugee distress and their aspirations for and performances of social healing. The model of social healing developed builds on the emerging critique of a psycho-social discourse as it relates to refugees in a resettlement context that represents and problematizes refugees in certain ways. The author argues that the contemporary psycho-social approach, embedded in a therapeutic discourse, constitutes refugees in particular ways that draw on a dominant paradigm that is therapeutically, individually and technically oriented. This dissertation interrupts this discursive practice through drawing on several critical intellectual traditions (anthropology, philosophy and sociology) and also through empirical work with Southern Sudanese refugees that supports the intellectual critique. The distress of Southern Sudanese refugees is made sense of through an alternative paradigm (to the dominant psychological, therapeutic and individually orientated one), through using key concepts such as cultural trauma, social trauma and social distress. These concepts orient the reader towards the collective, the social and refugee agency. Conversely a new social model of healing is then developed that explores the spheres and resources of, albeit disrupted, yet still existing, culture, community and power within the context of a dialogical and elicitive approach to intervention. The new social model provides a new map and new contours for building theory and identifying practice implications that draw on refugee emic perspectives, endogenous resources and insider action in a resettlement context. The dissertation has used an elicitive approach to research. The research methodology parallels the social model of healing articulated. Interviews, dialogue workshops and participant observation have been used to gain empirical and participant data. At the heart of the methodology is an elicitive process of dialogue that provides the opportunity for a mutual journey of discovery in re-building a social world of Southern Sudanese refugees within the spheres of: culture through for example, [re]orienting and [re]cycling cultural practice; community through for example, [re]creating bonding and bridging social capital, dealing with conflict, socializing suffering; and power through contesting political (structural and post-structural) dynamics linked to citizen rights, formal organized power, and engagement with the settlement and welfare industry. Overall the dissertation is a useful contribution to the ongoing debates about psycho-social and moral-political work with refugee communities within multicultural contexts.

The soldier’s life: martial virtues and hegemonic masculinity in the early Byzantine Empire

Stewart, Michael Edward — 2013-01-21T22:04:41Z

The soybean nodulation inhibitory factor SDI

Lin, Yu-hsiang — 2012-08-13T00:00:00Z

The Space and Performance of Virtual Reality

Neal Harvey — 2010-06-15T00:00:00Z

In this dissertation’s study of virtual reality (VR), I focus my attention on two prominent types of VR: real virtualities and virtual realities. I argue that both are composed of performative acts of spatial production and that through the study of those acts, researchers can isolate and describe the difference between these two tropes of virtual reality. My thesis focuses on Henri Lefebvre’s theorisation of social space as the most detailed and appropriate spatial theory for such a process while Victor Turner’s liminal theory of social and ritual performance provides the necessary performative methodology to complement Lefebvre’s. My use of these theories allows researchers to identify the difference between social spaces that produce new spaces and practices, and those which reinforce the spatial paradigm that generated them. The process of identifying these differences further clarifies Lefebvre’s complicated description of social space, but it also provides a platform for researchers to distinguish between the two different types of virtual reality. Through a detailed examination of three ostensibly different examples of VR, I argue that virtual realities ought to be considered primarily as realities made virtual while real virtualities should be discussed as virtualities made real. In doing so this thesis advances the study and application of Lefebvrean thought whilst opening up new directions for virtuality studies. I have chosen to explore three case studies that, through their difference, foreground their spatial and performative nature. By focusing on distinctly different and atypical case studies, I highlight the methodology described in this project and its suitability (or otherwise) for discussing VR. Focusing firstly on Google, I explore the virtual reality of the World Wide Web, perhaps the most ubiquitous example of a virtual reality. The sheer pervasiveness, uptake and constant evolution of the World Wide Web means that it requires constant academic attention. Google is the page through which a staggering 53.3% of Web users access the Internet and to say that most people are actually browsing Google’s web instead of the actual web is by no means an under statement. Google, like all other search engines, has its own formula for determining results and rankings for search queries. Google is not, as many people would like to think, an objective map of the Internet. It relies so heavily on users’ data in relation to their search query (which pages they click on, how long they spend there, whether they click back) that apart from the virtual algorithms that it uses to articulate the process Google could be said to be constituted solely by the real world practices of its users. Secondly I explore an example of the other type of VR, a real virtuality. Though the Gothic cathedral may not traditionally fall under the rubric of virtuality studies, the building itself provides an excellent example of the interaction of space and performance required to bring into existence that which was not there before. The Gothic cathedral is a concrete resolution of the actual/virtual dialectic and provides a unique opportunity to test my methodology’s ability to describe both types of VR and highlight the distinction between them. Whereas much of what constitutes virtuality studies centres on what I am calling the virtualisation of reality (online chat rooms, virtual banking, etc) – spaces that represent virtual others of real world entities, the Gothic cathedral represents the reverse of this: the realisation of a virtuality. The Gothic cathedral is unique in the context of this thesis for it is first and foremost a physical building rather than an onscreen other. It is a real virtuality in this thesis because, while concrete, there are some aspects of its reality that remain essential rather than formal and are dependent upon parishioners’ performance in order to be made ‘real.’ The final case study of this project represents the future usefulness of my methodology. In following up the work on exploring the suitability of describing a Gothic cathedral alongside Google, the last chapter of my dissertation explores the suitability of describing theatrical space as a VR. Similar to the Google chapter, this chapter focuses on a digital VR tool recently developed by Joanne Tompkins at the University of Queensland called the Online Theatre Project. The Online Theatre Project (OTP) represents a unique approach to the documentation, digital conceptualisation and archival problems that present themselves to a working theatre company in its everyday practice. The OTP is a server-based modeling and archival tool that allows users to draw, model and design their theatre production in real-time and then house their data on a remotely accessible server. Any notional description of theatrical space is necessarily a slippery one, given the relative youth of such studies and this project positions itself in this ever evolving debate by suggesting that the Online Theatre Project actually provides a description of what theatrical space entails where others have not. This thesis argues that VR space is dependent upon a constant spatial and performative production process. It illustrates how Lefebvre’s conceptualisation of the production process is most suitable for describing that production process and argues that re-imagining Lefebvre’s definition with the assistance of Turner’s everyday performative theory of liminality affords researchers the chance to differentiate between real virtualities and virtual realities. In doing so this thesis advances the study of VR, by proving that it is possible to discuss such complicated subjects in spatial and performative terms instead of the dominant real or un-real ones. Further, I outline the necessary adaptation of Lefebvre’s spatial triad that can be undertaken to prove its usefulness in many other aspects of VR studies.

The spacing effect in inductive learning

Zulkiply, Norehan — 2012-09-03T00:00:00Z

The spatial and temporal distribution of the metal mineralisation in Eastern Australia and the relationship of the observed patterns to giant ore deposits

Robinson, Larry — 2008-11-21T00:00:00Z

The introduced mineral deposit model (MDM) is the product of a trans-disciplinary study, based on Complexity and General Systems Theory. Both investigate the abstract organization of phenomena, independent of their substance, type, or spatial or temporal scale of existence. The focus of the research has been on giant, hydrothermal mineral deposits. They constitute <0.001% of the total number of deposits yet contain 70-85% of the world's metal resources. Giants are the definitive exploration targets. They are more profitable to exploit and less susceptible to fluctuations of the market. Consensus has it that the same processes that generate small deposits also form giants but those processes are simply longer, vaster, and larger. Heat is the dominant factor in the genesis of giant mineral deposits. A paleothermal map shows where the vast heat required to generate a giant has been concentrated in a large space, and even allows us to deduce the duration of the process. To generate a paleothermal map acceptable to the scientific community requires reproducibility. Experimentation with various approaches to pattern recognition of geochemical data showed that the AUTOCLUST algorithm not only gave reproducibility but also gave the most consistent, most meaningful results. It automatically extracts boundaries based on Voronoi and Delaunay tessellations. The user does not specify parameters; however, the modeller does have tools to explore the data. This approach is near ideal in that it removes much of the humangenerated bias. This algorithm reveals the radial, spatial distribution, of gold deposits in the Lachlan Fold Belt of southeastern Australia at two distinct scales repeating patterns every ~80 km and ~230 km. Both scales of patterning are reflected in the geology. The ~80 km patterns are nested within the ~230 km patterns revealing a self-similar, geometrical relationship. It is proposed that these patterns originate from Rayleigh-Bénard convection in the mantle. At the Rayleigh Number appropriate for the mantle, the stable planform is the spoke pattern, where hot mantle material is moving upward near the centre of the pattern and outward along the radial arms. Discontinuities in the mantle, Rayleigh-Bénard convection in the mantle, and the spatial distribution of giant mineral deposits, are correlative. The discontinuities in the Earth are acting as platforms from which Rayleigh-Bénard convection can originate. Shallow discontinuities give rise to plumelets, which manifest at the crust as repeating patterns ranging, from ~100 to ~1,000 km in diameter. Deeper discontinuities give rise to plumes, which become apparent at the crust as repeating patterns ranging from >1,000 to ~4,000 km in diameter. The deepest discontinuities give rise to the superplumes, which become detectable at the crust as repeating patterns ranging from >4,000 to >10,000 km in diameter. Rayleigh-Bénard convection concentrates the reservoir of heat in the mantle into specific locations in the crust; thereby providing the vast heat requirements for the processes that generate giant, hydrothermal mineral deposits. The radial spatial distribution patterns observed for gold deposits are also present for base metal deposits. At the supergiant Broken Hill deposit in far western New South Wales, Australia, the higher temperature Broken Hill-type deposits occur in a radial pattern while the lower temperature deposits occur in concentric patterns. The supergiant Broken Hill deposit occurs at the very centre of the pattern. If the supergiant Broken Hill Deposit was buried beneath alluvium, water or younger rocks, it would now be possible to predict its location with accuracy measured in tens of square kilometres. This predictive accuracy is desired by every exploration manager of every exploration company. The giant deposits at Broken Hill, Olympic Dam, and Mount Isa all occur on the edge of an annulus. There are at least two ways of creating an annulus on the Earth's surface. One is through Rayleigh-Bénard convection and the other is through meteor impact. It is likely that only 'large' meteors (those >10 km in diameter) would have any permanent impact on the mantle. Lesser meteors would leave only a superficial scar that would be eroded away. The permanent scars in the mantle act as accidental templates consisting of concentric and possibly radial fractures that impose those structures on any rocks that were subsequently laid down or emplaced over the mantle. In southeastern Australia, the proposed Deniliquin Impact structure has been an 'accidental template' providing a 'line-of-least-resistance' for the ascent of the ~2,000 km diameter, offshore, Cape Howe Plume. The western and northwestern radial arms of this plume have created the very geometry of the Lachlan Fold Belt, as well as giving rise to the spatial distribution of the granitic rocks in that belt and ultimately to the gold deposits. The interplay between the templating of the mantle by meteor impacts and the ascent of plumelets, plumes or superplumes from various discontinuities in the mantle is quite possibly the reason that mineral deposits occur where they do.

The Specification and Refinement of Timed Processes

Mahony, Brendan Patrick — 2008-11-21T00:00:00Z

The use of predicate transformers to model the action of sequential programs has allowed the construction of a refinement calculus for expressing the formal verification of the top-down development of sequential programs. It is shown that predicate transformers may also be used to model real-time processes. The notions of precondition and postcondition in the sequential refinement calculus are replaced by the notions of assumption and effect. In this way the formal development of real-time processes may also be expressed within the refinement calculus. Notations are developed for the specification and implementation of real-time processes within the framework of the refinement calculus. Several case-studies are presented to demonstrate the utility of this approach.

The spectroscopic properties of melanin

Riesz, Jennifer Jean — 2008-11-21T00:00:00Z

Melanin exhibits a broadband absorbance spectrum that appears to be unique amongst func- tional biomolecules. Explaining the origin of this spectrum is one of the primary challenges facing this field. Three main theories have been proposed: 1) The optical density is due to scattering, 2) Melanin is an amorphous semiconductor which then naturally exhibits broad- band absorbance, or 3) Melanin has a large amount of chemical heterogeneity (or disorder) which leads to a broadband absorbance spectrum through superposition of the absorbance spectra of many species (the chemical disorder model). We discuss these models and the experimental evidence for each. We report direct experimental evidence that the optical density is not a consequence of scattering processes, and is due to true absorbance. Distin- guishing between the two remaining explanations leads us to a discussion of the molecular structure of melanin, an issue which remains unresolved. We include a literature review, summarising the important structural findings for melanins, and conclude that the evidence suggests that melanin consists of a heterogeneous collection of small oligomers, which points towards the chemical disorder explanation for broadband absorbance. We caution, however, that the amount of chemical disorder obviously prevalent in this system is often neglected in discussions of the structure of melanin. We show that the oscillator strengths of melanin and its fundamental components are naturally explained by the chemical disorder model, as are their emission and excitation spectra and their radiative quantum yields. We show that the emission properties of melanin are not consistently reported in the literature, which is in part due to the strong re-absorption that occurs in this system, and we emphasise the im- portance of correcting for this effect in any measurement of the fluorescence of melanin. The emission properties of synthetic pheomelanin are reported, and are found to be different to those for eumelanin, suggesting different energy dissipation processes for these pigments. We also report a careful study of the spectroscopic properties of DHICA (5,6-dihydroxyindole-2- carboxylic acid), a key melanin monomer, and propose, based on these results, that proton transfer processes contribute to energy dissipation in this molecule. The radiative yield of melanin is measured to be extremely small (< 0.1%), which is consistent with melanins biological role as a photoprotectant, and suggests that non-radiative energy dissipation pro- cesses are very important for melanin. As a result of this finding we measure the vibronic structure of eumelanin related molecules using inelastic neutron scattering and accurately assign the vibrational modes using density functional theory calculations. This provides an important first step towards understanding the non-radiative processes in melanin energy dissipation and its biological functionality.

The Storied Landscape: A Queensland Collection

Luke Keogh — 2011-08-22T00:00:00Z

History’s train travels across the country capturing a film as it goes. The view from the train makes immediate the motion intrinsic to all landscapes. But this train, this film of the landscape, is not silent. Listen. There are words and stories and storytellers to be found: an intimate and evocative map of the landscape embedded with literatures and histories. To celebrate its sesquicentenary of responsible government an historical steam train travelled throughout Queensland, a north-eastern state of Australia. The train moved along a resource pathway from Mount Isa in the far west and travelled all the way to Townsville on the east coast; from cattle country to cane country, and all the while it was powered by Blair Athol’s famous steaming coal. It was an extraordinary moment in Queensland environmental histories where an image of resources collided with history and landscape. Sites of such wreckage are not just to be found with celebratory historical steam trains, but are scattered across Queensland. Indeed, so frequently do stories, landscapes and commodities collide, that they fuel The Storied Landscape. Commodities and resources are a defining way that Queenslanders have engaged with their environment. And so the archive of the land, the feel of its history, continuously leaves the residue of things. This thesis is a collection of stories and landscapes but it is a distinctly Queensland collection with resources framing the study. Three exploratory historical case studies focus on the Queensland commodities of pituri, coal and sugar. Challenging the normative economic perspective often given to these commodities, especially coal and sugar, the approach adopted here develops new ways of looking at landscapes transformed by resource extraction. In other words, not how big the hole in the ground is or how many acres of land have been cleared, rather how the landscape enters the mind and remains there. Such visions and contradictions are critical in the ways we continue to look at landscapes and the decisions made about changing them. This is an environmental history with a creative logic, which engages with recent anthropological works of ‘ethnographic natural history’. Stories and landscapes have material connections and to explore this means looking at the roots that stories take in the landscape. Such material connections form this Queensland collection. There is a map, a road sign for tourists, a lost natural history specimen, a colonial novel, an Aboriginal dreaming story collected by a pastoralist, a government report about a coal seam, a poem by a miner’s son, an ironbark prop, a pyramid, a collection of historical bulletins and a grave. A collection so diverse one wonders if a train could ever travel through so many places. Yet throughout this journey the storied landscape will persist as a central way to understand and see Queensland. Moving like a resource train across the country, the thesis stops at certain moments in time and space and collects stories and landscapes and explores the roots between them. How all this unfolds is a matter for this story. All aboard.

The story of alpha-conotoxins, Vc1.1 and RgIA, on their journey to becoming therapeutics

Reena Halai — 2010-05-07T00:00:00Z

Abstract The broad aim of this thesis is to structurally and functionally explore two α-conotoxins, from venomous sea snails, Vc1.1 and RgIA, in the hope of improving their journey to becoming analgesic therapeutics (introduction to conotoxins in Chapter 1). Vc1.1 is a two-disulfide peptide that is of interest as a potential therapeutic for the treatment of neuropathic pain. Despite investigations, limited structure-activity relationships have been conducted on this α-conotoxin. Consequently there is restricted insight into the interaction of this peptide with one of its analgesic targets, the α9α10 nicotinic acetylcholine receptor (nAChR). Late in this PhD project, the GABAB receptor was implicated as the possible target for conotoxins in neuropathic pain relief. However, there is still debate in the literature with regard to the true target of Vc1.1 and the α9α10 nAChR is still believed to be the target by some groups. This thesis predominantly focuses on the α9α10 nicotinic acetylcholine receptor. Chapter 4 of this thesis presents an extensive series of mutational studies in which all residues except the conserved cysteines were mutated separately to Ala, Asp or Lys (materials and methods described in Chapter 3) and examined using NMR spectroscopy (theory of NMR presented in Chapter 2), to determine the effects of the mutations on the structure of Vc1.1. The structural fold was found to be preserved in all peptides except where Pro was substituted. Chapter 5 explores the effect of these mutations on the blocking of acetylcholine (ACh)-evoked membrane currents at the α9α10 nAChR. Electrophysiological studies showed that the key residues for Vc1.1’s activity are Asp5-Arg7 and Asp11-Ile15, as changes at these positions resulted in the loss of activity at the α9α10 nAChR. Interestingly, the S4K and N9A analogs were more potent than Vc1.1 itself. Hence, Chapter 6 describes a second generation of mutants that was synthesized, namely N9G, N9I, N9L, S4R and S4K+N9A, all of which were more potent than Vc1.1 at both the rat α9α10 and the human α9/rat α10 hybrid receptor, providing a mechanistic insight into the key residues involved in eliciting the biological function of Vc1.1. The most potent analogs were also tested at the α3β2, α3β4 and α7 nAChR subtypes to determine their selectivity. All mutants tested were most selective for the α9α10 nAChR. These findings provide valuable insight into the interaction of Vc1.1 with the α9α10 nAChR subtype and will help in the further development of Vc1.1 or its analogs as drugs. However, despite peptides exhibiting high degrees of potency and selectivity, such as Vc1.1 and RgIA, they are potentially hindered in their development as drugs due to their stability and bioavailability limitations, leading to invasive delivery techniques. Chapter 7 presents a range of cyclic RgIA analogs, tested at their targets the α9α10 nAChR and the GABAB receptor, that retain their activity and increase their stability in human serum relative to non-cyclic RgIA. NMR spectroscopy was used to determine the structure of the non-cyclic peptide and the cyclic peptide to confirm similarities in the global fold of the peptide. Structural perturbations and reduced activities were observed for cyclic RgIA analogs cyclized via linkers composed of three and four residues. Analogs with five, six and seven residues showed no structural perturbations, but differences in their activities at the different receptors. Because cRgIA-6 showed high potency for the GABAB receptor and lower potency for the α9α10 nAChR, this study has identified a GABAB selective peptide. Additionally, because the cRgIA-7 showed high potency for the α9α10 nAChR and low potency for the GABAB receptor, a α9α10 nAChR selective analog has also been identified. With improvements in these peptides against enzymatic attack, they show great potential on their path to becoming orally available analgesics as they may be able to withstand enzymatic conditions in the stomach.

The Strategic Planning of Post Disaster Reconstruction (A Case Study of Banda Aceh’s Reconstruction)

Mr . Aulia Sofyan — 2011-02-16T00:00:00Z

This thesis investigates the reconstruction of Banda Aceh after the disastrous earthquake and tsunami of December, 2004. It fits the investigation within a framework derived from the literature on disaster studies and disaster recovery. The fundamental issue addressed in the thesis is the delays apparent in the reconstruction process even though a new government agency (BRR, or the Aceh and Nias Reconstruction and Rehabilitation Agency) was created to expedite reconstruction. The questions that underpin the research are concerned with the factors that hinder and support effective and speedy reconstruction; the thesis then reaches conclusions and makes recommendations on the basis of this investigation. The study used a number of research approaches, including interviews with 50 members of the community, with public figures, with representatives of donor organizations and NGOs from abroad and with national, provincial and local government officials. The interviews were supported by data from focus group discussions, as well as official reports and documents and the wider literature. The author was also able to use participant observation to support and guide the other research methodologies. The author was able to work closely with BRR in discussing in the field problems and obstacles that faced the implementation of BRR programs. The field work for the study was carried out in two six-month periods in 2005 and 2006. The research showed the approach needed for an effective reconstruction program in Aceh should enhance communication among stakeholders, build stronger coordination mechanisms amongst these stakeholders, build an effective bureaucracy working within an effective governance system, improve community involvement in the recovery process, strengthen the local government capacity and increase the level of practical and effective commitment from donors and NGOs. These are all aspects that have been listed in the literature as components of effective reconstruction after natural disasters. In general, the thesis research supports these conclusions. An issue that was of special significance in Banda Aceh was the impact of the level of international sympathy and support. Although this is a feature of many international disaster responses the reconstruction in Banda Aceh showed how critical is the actual level of delivery of assistance compared to the level of promises of assistance. The general recovery process faced obstacles that arose from the presence and absence of factors that can aid reconstruction: lack of communication among stakeholders, lack of coordination among stakeholders, ineffective bureaucracy, lack of community participation, lack of human resources, and unfulfilled promises to the communities. However, the case study showed that factors that strongly support the rehabilitation and reconstruction in Aceh are the strong budgetary commitment by central government, strong financial support from donors and NGOs and the powerful mandate of BRR to aid the reconstruction. A special circumstance that applied in Banda Aceh was the ceasefire agreements in the preceding civil strife and the agreement of both sides to assist in the reconstruction. The role of BRR has been very significant and effective in the implementation of the reconstruction programs, in the light of these constraints and opportunities. However, BRR faced many challenges. BRR was less successful than intended in re-housing tsunami victims. The reasons for this are indicated in the research findings, but some of the difficulties arose from cultural differences between BRR staff and the local population. The thesis used an institutional framework based on the work of Healey (2002) and Van Horen (2005). Through this, several forms of community assets (or capital) are identified that need to be in place for full community sustainability, and thus are needed as the basis for recovery after natural disasters. These forms of capital were used to assess the optimal framework for Aceh’s recovery and reconstruction. Physical and natural assets are the most obvious assets impacted on by a natural disaster such as the Aceh tsunami. Economic assets are not so immediately obvious but nonetheless are still important. These are also assets that are relatively easily identified and addressed (although often imperfectly) by international aid agencies. Human and relational capitals were shown in the case of Banda Aceh to be of particular importance and so should be flagged as a concern for post-disaster reconstruction. Similarly the strong Muslim ethic of the Aceh community was identified as being fundamental to the approach that should be used in reconstruction; in this way the spiritual aspects of cultural capital was seen as especially important in Aceh. Both Healey (2002) and van Horen (2005) recognize the governance framework within which these assets are utilized as critical for the development of values such as transparency and accountability.

The Structural Basis for Interaction Between Colony-Stimulating Factor-1 and Its Receptor, CSF-1R

Hamwood, Tamarind — 2008-11-21T00:00:00Z

Macrophages are white blood cells involved in many aspects of host defence, immunity, pathology and homeostasis. Colony-stimulating factor-1 (CSF-1) is required for normal proliferation, differentiation and maturing of macrophage lineage cells. CSF-1 binds to its proto-oncogene receptor, CSF-1R (also known as c-fms) to induce phosphorylation of cytoplasmic tyrosine residues on the receptor and activation, which initiates molecular signalling cascades leading to specific gene regulation. Given the central role of macrophages in immunity and pathology, CSF-1 and its receptor are obvious drug targets. This study involves the structural characterization of the interaction between CSF-1 and its receptor with the eventual aim of designing novel therapeutics to act antagonistically on CSF-1R. Three approaches were taken towards this aim. In Chapter 3, molecular modelling and inter-species cross-reactivity of CSF-1 was used to identify residues likely to be involved in the interaction between CSF-1 and its receptor. The crystal structure of human CSF-1 (PDB code 1hmc), a four-helix bundle cytokine, was used to create a model of murine CSF-1. The CSF-1R is a type III receptor tyrosine kinase (RTK), with five extracellular immunoglobulin-like (Ig-like) domains, a single transmembrane region and a cytoplasmic kinase domain. The ligand-binding regions, located within the three N-terminal Ig-like domains of the receptor, were modelled on similar cell-surface receptors. An investigative comparison of mouse and human structural models identified seven residues on mouse CSF-1R as candidates for interaction with CSF- 1 based on structural location, solvent exposure, electrostatic complementarity, evolutionary conservation and prevalence in protein-protein interaction sites. To further explore these residues, mutated CSF-1R constructs were assayed in two independent systems. The first assay utilized endogenous signalling by CSF-1R that leads to transcriptional activation of urokinase plasminogen-activator (uPA). Mutant or wild type CSF-1R constructs were co-transfected with a luciferase reporter construct under regulation of the uPA promoter. Luciferase activity measured CSF-1-dependent CSF-1R signalling, to identify mutant receptors not capable of responding to CSF-1. Mutant receptors were also assayed for the ability to promote CSF-1-induced growth in the Ba/F3 cell line. Evidence from both assays confirmed that R127, Y238 and W140 are essential for CSF-1-induced activation of the receptor. Due to the complex disulfide-linkages and glycosylation patterns of CSF-1 and CSF-1R, obtaining crystallization amounts of pure protein required empirical study of different expression systems. As the interaction does not require the transmembrane domain, only the ligand-binding regions of murine CSF-1R were included in the his-tagged constructs. The first contained the entire extracellular region (F15), while shorter truncations contained either the N-terminal three domains (F13) or the second and third Ig-like domains (F23). In Chapter 4, these constructs and CSF-1 were expressed in bacteria as inclusion bodies, purified to homogeneity by metal-affinity chromatography and refolded in the presence of disulfide-exchange factors. While CSF-1 refolded with little aggregation, receptor proteins showed significant aggregation upon removal of denaturants. To overcome aggregation during refolding, receptor constructs were cloned into a baculovirus vector for expression as a secreted protein in a eukaryotic insect cell system. In Chapter 5, insect cell production of CSF-1R proteins for large-scale production was optimised. Chapter 6 describes various assays for protein integrity and activity that were undertaken on the proteins produced in Chapters 4 and 5. In particular, the native activity of CSF-1 to promote bone marrow macrophage growth was examined, as was the ability of soluble receptor and neutralizing antibody to prevent this activity. Additionally, an assay amenable to high-throughput screening for agents that interact specifically with the extracellular domains of CSF-1R was developed in the Ba/F3 cell line. This assay shows excellent dosedependent response to CSF-1, with maximal activity double the baseline activity, and may be used to identify both agonists and antagonists of the interaction.

The structural determinants of quality in residential aged care.

Richardson, Beverley Frances — 2008-11-21T00:00:00Z

The sustainability of the pig and poultry industries in Santa Catarina, Brazil: a framework for change

Spies, Airton — 2008-11-21T00:00:00Z

This study begins with a review of the concept of sustainability and sustainability indicators in the context of the pig and poultry industries in Santa Catarina State (SC), in Southern Brazil, and proposes an approach to the development of sustainability indicators for these industries. A review of the background and current situation of the pig and poultry industries in SC revealed that they are well organised into vertically integrated production systems and are regarded as being very competitive in world markets from technical and economic points of view. In 2002, SC produced 24% of total pork and 20% of total chicken production in Brazil in 2002, but this State has an area of only 95,000 km2, which amounts to just 1.1% of the country. SC also contributed 66% of pork exports and 54% of poultry exports from Brazil in 2002. So far the pig and poultry industries in SC have developed successfully, but recent changes towards more intensive production methods have resulted in much concern being expressed by the community, as the environmental impact of waste produced in the region has increased. The review of literature showed that in order to be sustainable, the pig and poultry industries in SC should acknowledge the concept of the triple bottom line and the principles of ecologically sustainable development. These include (i) biophysical or environmental sustainability, (ii) economic viability and (iii) social sustainability as criteria to guide industry development. The sustainability of the pig and poultry industries is influenced by local, regional, national and global factors which operate on several scales, and which in turn, indicate the need to use a multi-dimensional approach, combining environmental, economic, and social attributes. This study used a combination of qualitative and quantitative methods and was completed in four phases. In the first phase, an electronic survey of 205 stakeholders (complemented by 60 interviews with farmers) was undertaken to identify their views and perceptions of what sustainability meant to them. The survey was also designed to obtain stakeholders views on a suggested list of sustainability indicators. In Phase 2, the findings of the e-survey were discussed with panels of key industry stakeholders in 4 focus group discussions with of 47 participants to develop the list of indicators. In the third phase, a streamlined Life Cycle Assessment (LCA) study was conducted, to quantify the flows of materials, energy and of natural resource uses and to assess environmental impact. Finally, in Phase 4, stakeholder feedback was sought in 9 meetings to discuss and refine preliminary results and conclusions from the previous three phases of work. In the LCA the environmental burdens produced by typical intensive pig and poultry production systems were quantified and the contribution to each of nine selected environmental effects was estimated. The functional units (FU) were 1 tonne of live weight (LW) of pigs and 1 tonne of LW of chickens delivered to the gate of the abattoir. The boundaries of the systems analysed included the processes of producing fertilisers, feed products (maize and soybeans), energy, fuel, pesticides, production of rations, production of pigs and chickens and transportation required during all stages until the pigs and chickens are delivered to the abattoir. Data were collected from a variety of sources, including pig and poultry industry operators, research institutions, and agribusiness analysts from SC, as well as publicly available databases. Identified environmental hotspots in pig production were greenhouse gas emissions, acidification, and eutrophication, particularly from ration production and waste management. Environmental hotspots for poultry production reflect the high use of energy and pesticides, particularly associated with ration production from soybeans. The study concluded that although economic performance is competitive in world markets, most producers were operating outside the boundaries of sustainability because of inadequate waste management and excessive waste produced in a small geographical area, beyond the assimilation capacity of the local environment. This also causes other environmental effects (such as offensive odours, and increased numbers of blackflies, and houseflies), which were not quantified in the LCA study, but which were regarded as very important issues by stakeholders in the survey and focus group discussions. While comparing the overall environmental impact of producing 1 FU of pigs and poultry, this study concluded that under current production systems, pigs cause 68% greater impact than chickens. The key indicators proposed to assess the sustainability of the pig and poultry industries in SC were grouped into physical or environmental, economic, and social indicators. For physical and environmental indicators, monitoring the natural resource condition is the key indicator and requires measurement of attributes such as manure load per area of land and nutrient balance (P and K), soil condition, water use and water quality, agricultural plant species diversity, impact on native vegetation, and chemical residues in products. Among the economic indicators, long-term real net farm income and the industries overall competitiveness in national and international markets are key indicators. Attributes to measure these indicators are real net farm income, cost of production, farmers terms of trade, total factor productivity, and disposable income per farm household. Other farm level technical indicators which influence the economic outcome, such as feed conversion and productivity indices for pigs and poultry, also need to be monitored. For social indicators, the age structure and gender balance of the agricultural workforce, farmers managerial skills and level of training, as well as access to basic services, such as health, education, communications, and electricity in rural communities, are the key sustainability indicators. This study made four main contributions to knowledge: (a) the views and perceptions about sustainability among pig and poultry stakeholders were identified; (b) the environmental impacts of pig and poultry production were quantified and compared; (c) a set of key sustainability indicators for the pig and poultry industries was developed and validated; and (d) a framework for change towards sustainability and policy guidelines were suggested. The overall conclusion of the study is that, to be sustainable, the pig and poultry industries need to adjust their management practices, policies, and development strategies to incorporate the principles of ecologically sustainable development. Feeding strategies and methods of grain production have much influence on the key points of environmental impact, such as global warming, pesticides, and energy consumption. Waste management, however, has the greatest local impact, because of water and soil pollution and reduction in the quality of life due to offensive odours, blackflies, and houseflies. Sustainability indicators can thus assist to drive the industries to adopt improvements in the production systems to achieve better environmental performance. Although the findings of this study are confined to SC, the principles are generally applicable to other similar livestock industries in other places. The main justification for conducting this study rests on the increasing demands by the government, community and industry stakeholders for initiatives to reduce the impact of the pig and poultry production on the environment, while maintaining and enhancing its economic competitiveness in global markets and continuing to deliver important social benefits.

The Synthesis and Characterization of Peptide-Based Carriers for Gene Delivery and Peptide Therapeutics

Daniel Coles — 2010-11-23T00:00:00Z

Gene therapy is a promising approach for the treatment of genetic diseases. Currently, there are no gene therapy drugs available on the market. There are many therapeutic genes available for treating various diseases but they are not delivered effectively to the target site. The size, negative charge and susceptibility of DNA to degradation can be overcome by using a gene carrier. Current gene carriers are divided into two groups, viral and non-viral. Viral carriers are very efficient but they can induce an immune response. Non-viral carriers are less efficient and sometimes toxic. The optimisation of gene carriers is an ongoing endeavour for researchers. We have designed gene carriers to overcome the barriers associated with gene delivery. These barriers include DNA stability, the cell membrane, endosomal membrane, nuclear membrane and dissociation of DNA/carrier complex. Therefore, our gene carrier design included a cell-penetrating peptide (CPP) TAT, a nuclear localization signal (NLS) peptide, dendritic polylysine and lipoamino acids (LAAs). The carriers were synthesized by solid phase peptide synthesis using Boc chemistry. They were purified by preparative RP-HPLC and characterized by mass spectrometry and analytical RP-HPLC. The carriers’ ability to form a complex with DNA was assessed by gel shift assay, dynamic light scattering (DLS) and zeta potential (zetasizer), isothermal titration calorimetry (ITC) and transmission electron microscopy (TEM). Cell uptake and gene expression were analysed by our collaborators. The carriers were successfully synthesized and were shown to form complexes with plasmid DNA. The gel shift showed a shift of the band to the well of the gel compared to free DNA. The sizes of the complexes were 60-100 nm according to DLS and TEM measurements. The zeta potential of the particles was positive when an excess of carrier was used. ITC experiments revealed that the ionic interaction between the carrier and DNA was strong and increased with the carriers possessing more positive charges. The cell uptake was high when TAT was used in combination with NLS and/or polylysine. Also, the inclusion of LAAs increased cell uptake in Jurkat cells. Gene expression was low for all carriers without the application of chloroquine, a lysosomotropic agent. The TAT peptide was synthesized with different polycationic dendrimers to determine the optimum type, composition and size of dendrimer. We found that a polylysine dendrimer with eight positive charges provided the best results. A different CPP, penetratin, was used to see if it employed a different mechanism of cell uptake and therefore increase gene expression. However, these carriers did not significantly improve gene expression because the complexes were trapped inside the endosome. Carriers incorporating a substitute for chloroquine, the N-terminal of the influenza virus haemagglutinin HA2, were synthesized to increase endosomal escape and therefore, gene expression. An improvement in gene expression only occurred when using high ratios of carrier (20:1) but still the gene expression was low and increased upon the application of chloroquine. An anticancer peptide, shepherdin, was enhanced by adding penetratin and a LAA to improve its cell uptake and to lower the concentration of administration required for a therapeutic effect. The inclusion of a LAA did improve shepherdin’s anticancer ability. However, the negative control peptide coupled with a LAA was also toxic to cancer cells. A LAA conjugated with thymine was assessed for its ability to hydrogen bond to single-stranded DNA and characterized by diffusion ordered NMR spectroscopy (DOSY), ITC and TEM. It was found that the LAA-thymine compound binds to DNA at a ratio of 1.7:1 (LAA-thymine:DNA). Additionally, a control experiment titrating LAA-thymine into a solution of adenine showed a ratio of 0.9:1. A selection of peptide vaccines were analysed by DOSY, DLS and mathematical expressions to determine their particle size and to compare the three methods used. DOSY yielded results that were closer to the expected size compared to DLS measurements. Also, the smaller the peptide, the more accurate the measurements were when compared to the expected size generated from mathematical models. Our investigations proved that combinations of CPPs, NLS peptides, charged dendrimers, fusogenic peptides and lipids can be applied for successful gene delivery.

The Synthesis, Physicochemical Characterization and Biological Interactions of Polymer-Coated Nanoparticles

I-Chun Lin — 2011-10-31T00:00:00Z

The versatility in the synthesis of polymer nanocomposites has allowed researchers to tune the size, surface charge and their function for use in various biomedical applications. However the behaviours of these engineered nanomaterials in biological systems are still being elucidated. Due to the different physico-chemical properties and multifunctionality, nanoparticles may interact with various biological components causing different toxic/health concerns. With means to improve the efficiency and the performance of engineered nanoparticles, it is necessary to understand the interactions of nanoparticles in the biological systems. For this purpose, a library of polymer coated nanoparticles (gold and silica) was designed with different sizes (5 nm ~150 nm) and surface properties (hydrophilic/hydrophobic, postive, negative and neutral surface charge). The polymers used were prepared by RAFT-mediated polymerization and grafted onto the nanoparticle surface. Grafting of polymers made by RAFT onto gold nanoparticles (AuNPs) gave a densely packed polmyer shell as quantified by thermogravimetric analysis (TGA). In comparison, polymers were found to have low grafting densities on SiNPs. The grafting desnity for the majority of polymers on the AuNP surface was around 0.7 ~1.4 chains/nm2. With such high grafting densities, the surface properties and the size of these hybrid nanoparticles were the only contributing factors affecting their behaviour in the biological system. The surface properties of the nanoparticles were known to play a crucial role in their interaction with cells. The uptake and transport of the nanoparticles library were investigated using epithelial Caco-2 cells, which represented an excellent model to resemble the human intestinal epithelium. The modification of the nanoparticle with the positively charged polymers (PAEA-AuNPs) gave the greatest uptake due to its high affinity to the negatively charged cell membrane. Interestingly, the uptake efficiency for PNIPAM-AuNPs (neutral charged but becomes hydrophobic at 37 oC) was much greater than the negative and neutral AuNPs. It is believed that this is caused by the hydrophobic interactions with the cell membrane or the increase in nanoparticle size. Despite the high level of cellular uptake of the hydrophobic and postive charged AuNPs, the translocation of these nanoparticles across Caco-2 cell monolayers was low. Instead these particles were trapped inside endocytic vesicles or endosomes in the cytoplasm as shown by TEM. Only the neutral PDHA, PEG-AuNPs and negative charged PAA-AuNPs were able to transport thorugh the Caco-2 cell monolayer with higher efficiency. Smaller nanoparticles were also found to have a greater translocation across cell monolayers compared to larger nanoparticles. All polymer-coated AuNPs displayed a marked effect on the translocation of small molecules across the cellular monolayer. This suggested that all tested nanoparticles can loosen the paracellular tight junction joing individual cells. The resistance values (TEER) of monolayers decreased upon the opening of tight junctions but generally recovered 12 h after removal of the polymer-coated AuNPs. The mechanism of nanoparticle cellular transport was investigated by endocytosis inhibition test. Transport of nanoparticle through the cell monolayer involved both a transcellular or paracellular pathway. The endocytic uptake and transport of nanoparticles underwent either a microtubule-dependent or microtubule-independent mechanisms. An interesting finding was that neutral polymer coatings (PEG and PDHA) facilitated different types of endocytic transport. The majority of the polymer coated nanoparticles tested also showed no apparent signs of toxicity from the in vitro assays. In summary, this thesis detailed the synthesis of nanoparticles with controlled sizes and presented a practical approach to modify the surface properties of different nanoparticles with polymers. These studies have provided insights on the influence of nanoparticle surface properties on their cellular interaction and toxicity. While numerous studies have started to examine the effect of nanoparticles surface properties on their biological interactions, many challenges and mystery in this area of research still remains to be solved. This nanoparticle library could potentially help researchers to forecast the biological properties of novel pharmaceutically important nanomaterials, aiding in their future design and use.

The tale of the two shoals: How individual experience influences shoal behaviour

Zehev Benzaken — 2010-08-31T00:00:00Z

This project examined how the spatial behaviour and cohesion of rainbow fish (Melanotaenia duboulayi) shoals are affected by the contrasting previous experience of individual shoal members. The main variables considered were: overall group size, the time since group members were exposed to a positive (food) or negative (threat) experience, and the proportions of shoal members having the two types of experience. The food and threat stimuli were introduced close to a habitat patch, to which fish were normally attracted. Shoals of ten or two fish were exposed to food or threat for thirty minutes. Their behaviour was then recorded in twenty- minute trials after different lengths of time had elapsed since exposure (0, 1, 24 and 48 hrs). Shoals made up of different combinations of food-exposed and threat-exposed fish were used (for ten-fish shoals: 0+10, 2+8, 5+5, 8+2 and 10+0; for two fish shoals: 0+2, 1+1, 2+0). Threat-exposed ten-fish shoals stayed away from the patch, whereas their food-exposed counterparts continued to use the patch. Such behaviour was consistent with expectations based on predator avoidance theory. However, the reaction of the threat-exposed two-fish shoals had a different reaction to the presented stimuli if compared to shoal with ten individuals. Smaller shoals continued to use the patch, possibly because of a protection trade-off where for a small group the refuge benefits of the patch outweighed the perceived risks associated with open water, or because of lower efficiencies in terms of learning and mutual reinforcement in small shoals. The effects of increasing time since exposure varied according to group composition (ratio of fish exposed to threat versus food). Thus, within the first hour after exposure, a shoal of ten threat-exposed fish moved away from the patch and began individual patch inspections, while ten food-exposed fish showed a smaller change in individual inspection frequency. After 24 hrs, all unevenly-mixed shoals had moved away from the patch, but after 48 hours shoals dominated by food-exposed individuals, but not those dominated by threat-exposed fish, were using it once more and performing more group inspections. These results showed that shoal behaviour was affected by a complex interaction between individual experience, group composition and the elapsed time since threat- or food-exposure. However, the uniform results with two-fish shoals indicated that the range of options for dynamic, risk-balancing behaviour involving factors such as memory and reprioritisation of experience was more limited when group sizes were low. Further work is proposed to investigate learning in shoaling and refuge time budgets. In summary, this project has shed some light on the poorly understood topic of how shoals perceive experiences and how memory of past experiences influences shoal behaviour.

The taxonomy and systematics of the coral genus Favia from Thai waters

Narinratana Kongjandtre — 2011-07-03T00:00:00Z

There is unequivocal evidence that the current changes in the global climate, coupled with increasing anthropogenic disturbance on reefs, pose serious threats to the future of coral reefs. As such, much emphasis has recently been placed on reef resilience. Biodiversity, however, is an important component underpinning resilience and its study via taxonomy is central to our understanding of coral reef ecosystems. Stable and accurate taxonomies are critical to an understanding the biodiversity on coral reefs, yet our understanding of the taxonomy and systematics of reef building corals is beset with problems and ambiguities. The genus Favia (Cnidaria: Scleractinia) is a particularly problematic group of corals with previous studies finding it to be non-monophyletic, with the Atlantic Favia and Indo-Pacific Favia being genetically distinct and nested among other genera and families. This thesis focuses on the taxonomy and systematics of Favia (with para-septothecal walls) and uncovers major problems with, and inconsistencies in, genetic markers currently used for corals. The non-homology of mt-IGR (COI-trnM region) and multiple copies of ITS present a huge challenge for using DNA sequences alone to delineate species of Favia (Chapter 4). This study explored ways to resolve some of the major problems within this important group resulting in some new insights into the evolution of Favia. Southeast Asian Favia appear to be largely monophyletic, when non-homologous copies of COI-trnM are removed (with the exception of Barabattoia amicorum, which was included along with a likely erroneous sequence of Goniastrea aspera from Genbank). The ITS region also recovers the monophyly of Favia (with para-septothecal walls) albeit with Barabattoia not sampled. Bayesian phylogenetic analysis of COI-trnM found no support for monophyly of F. pallida, F. cf. pallida, F. cf. lizardensis and the F. favus species complex; they were distributed in four clades that are sister to F. truncatus. In the ITS phylogeny, the four morphospecies were paraphyletic and haplotypes from each of these morphospecies were distributed among four poorly-defined clusters which were also sister species to F. truncatus, however with no support. This thesis found little support for the current circumscription of many species, including F. pallida, F. cf. pallida, F. cf. lizardensis and members of the F. favus species complex. Even though current taxonomy is mostly based on morphology, analyses of morphological data also failed to recover the described species (Chapter 5). Application of a Phylogenetic Species Concept (PSC) failed to recover current species and provided little resolution for alternative taxonomies (Chapter 4). Similarly, if considered under a Biological Species Concept (BSC), current species could not be separated and there were no alternative groupings (Chapters 3, 6). Nontheless, there is conclusive genetic evidence to show that F. truncatus and F. cf. helianthoides each represent a well-supported monophyletic group in both ITS and COI-trnM DNA regions. In addition, they are each reproductively isolated from other species and are thus separate species under both the PSC and the BSC (Chapters 4, 6). Furthermore, using the hooded appearance of the corallite as a character, F. truncatus is further defined under a Morphological Species Concept (MSC). On the other hand, the morphology of F. cf. helianthoides often overlapped with the highly variable morphology of the F. favus species complex and could therefore not be resolved under the MSC (Chapter 5). Chapters 4 – 6 reveal evidence for the non-monophyly for four morphospecies of Favia. Favia pallida, F. cf. pallida, F. cf. lizardensis and the F. favus species complex spawned on the same nights with ability for inter-breeding and highly compatible gametes between morphospecies, although testing for the presence of any post-zygotic isolating barriers was not included in this study. Therefore, these morphospecies have been rejected by the PSC and the BSC. More flexible species concepts such as the ‘genotypic cluster’ concept allowed the delineation of polytypic species. Chapter 5 therefore tested the ‘genotypic cluster’ against the MSC by testing the hypothesis that morphospecies represent natural taxa and are congruent with species described under the ‘genotypic cluster’ concept. This thesis reveals that, whilst showing some merit, morphological methods alone are limited in their ability to accurately classify proposed unknown specimens (potential hybrids) when specimens were identified based on a priori species information using morphospecies and genotypic clusters (ITS and COI-trnM). A direct comparison between genetic and morphological information suggests that the ‘genotypic cluster’ concept is more robust at revealing species boundaries between Favia. The work embodied by this thesis has significantly expanded knowledge about the role of introgressive hybridization within the Southeast Asian Favia and provided a novel perspective of these important species within a number of species concepts. Inferring phylogenies from mitochondrial versus nuclear gene trees has allowed unknown specimens (potential hybrids) to be identified suggesting that this approach should be used in future studies. Significant genetic differentiation between F. pallida and the F. favus species complex, well separated using morphological characters and a small gap in spawning time between 18.30 – 20.00 hours (the F. favus species complex) and 20.30 – 21.30 hours (F. pallida) supported the hypothesis that the two species were once distinct biological species. However, the lack of genetic differentiation observed between F. cf. pallida and F. cf. lizardensis, high genetic connectivity, and gamete compatibility across morphospecies, provided evidence that there has been gene flow between morphospecies of Favia. The present thesis emphasizes the lack of pre-mating barriers for genetic exchange to maintain species boundaries within Favia. In summary, non-monophyly observed using ITS and COI-trnM DNA regions reflect syngameons that are capable of introgressive hybridization. This thesis also demonstrates the importance of using both life history and molecular studies across the broad geographic range of corals. Comparisons between multiple study sites have also been shown to be informative to define hybridization zones. This thesis recognizes some morphological characters such as septa teeth, septa size and thickness, number of septa and wall thickness as useful in distinguishing the morphospecies of Favia. Further study on septa details by the use of the scanning electron microscope may provide new insight into morphological traits in the species of Favia. Incorporating environmental parameters from each location and transplantation experiments would provide a better understanding of phenotypic plasticity among different genotypes and species.

The Technology Of The Præternatural: An Operational Analysis and Empirical Study of the Psycho-Phenomenology of Mystical, Visionary and Remote Perception Experiences

Nelson, Peter Laurence — 2008-11-21T00:00:00Z

In Part I of this thesis, mystical experience is defined in terms of some of the classical philosophical and psychological issues which surround it. It is also connected to the general class of the præternatural which is defined operationally as those visionary and remote perception experiences which have a quality of supernaturalness as defined by Hultkrantz. The psycho-phenomenology of these states, taking mystical experience as the sine qua non of præternatural experiences, is developed from both religious and secular perspectives and related to issues of psychopathology. This is followed by a discussion of the problems of interpretation and an ontologically neutral, operational and phenomenological method, which emphasizes the how rather than the meaning of these experiences, is posited. This approach then is cast in the mould of consciousness studies as the most suitable theoretical position from which to pursue the paradigm of the how. The next part of this section examines contemporary theories of consciousness and critiques them in terms of their ontological assumptions, epistemological ascriptions and suitability for an empirical, operational, psycho-phenomenological study of human experience. This examination commences with the non-consciousness of James Radical Empiricism and the phenomenological position as re-interpreted by Sartre in Chapter 3 and continues in Chapter 4 with an analysis of the psychological-cognitive and neurophysiological reductive hypotheses current today. It concludes with the notion of consciousness which arises from the current interpretations of modern physics. Chapter 5 attempts to build a concept of consciousness as pan-consciousness which is strictly operational and free of ontological grounding. In this notion, things, objects, states and human observers all arise as the reflective processes of pan-consciousness as process without the need for a final location or object. This section closes with a suggestion for a method of empirically studying experience within the proposed theoretical context. Part II is an exploratory investigation of the operational and phenomenological aspects of præternatural experience. The three dimensions of Personality, Operational and Phenomenological as the basis of experience are defined and set in the context of psycho-phenomenological research using verbal reports as data. The first part of the investigation, reported in Chapter 7, is a non-random survey of the populations of Queensland and Griffith universities and it reveals a level of occurrence consistent with the 20-40 percent found in overseas studies such as those of Hay and others. Chapters 8 and 9 detail an in-depth psycho-phenomenological study of 120 cases drawn from the original sample. Using Direct Discriminant Function Analysis and Principal Components Analysis an empirical case is made for two general types of præternatural experience - Ontic and Perceptual. This exploratory investigation also establishes differences on all three dimensions between præternatural experience and normal, everyday, veridical experience. It appears, therefore, to extend Tarts theoretical position as well as confirming some of the preliminary research on mystical experience conducted by Hood and others while opening a new, three-dimensional, approach to the study of experiential states.

The Termination of the Last Glacial Cycle in eastern Australia: A High Resolution, Multiproxy Analysis

Lynda Petherick — 2012-06-05T00:00:00Z

A continuous, high resolution (average ca. 22 year) record encompassing the termination of the Last Glacial Cycle (LGC) (defined here as ca. 31 – 18 kyr) has been developed using multiple proxies (viz. sediment flux, grain size, moisture content, pollen and charcoal) in lake sediment from Tortoise Lagoon (TOR), North Stradbroke Island (NSI), Queensland, Australia. This record is one of only two available from the lowland subtropics of Australia which are continuous through the termination of the LGCLGC. As such, the TOR record assists in bridging an extensive spatial gap between the records of palaeoclimatic and palaeoenvironmental variability from the tropical north and temperate south. The presence of key pollen taxa (e.g. Asteraceae (Tubuliflorae) and spineless Asteraceae, which are common indicators of glacial conditions in Australia) at TOR indicates significantly cooler temperatures (mean annual temperature up to 11oC lower than today) extending into the subtropics. Pollen taxa present also indicate mean annual precipitation up to 65% lower than modern. Similarities between the vegetation at TOR during the Last Glacial Maximum (LGM) and that at temperate sites e.g. Caledonia Fen, Victoria (Kershaw et al. 2007b), Redhead Lagoon, New South Wales (Williams et al. 2006) and Barrington Tops, New South Wales (Sweller and Martin 2001) suggests that this record reflects regional conditions across southeastern Australia. The TOR record also correlates well with that from nearby Native Companion Lagoon which suggests that the LGM was actually an extended period of ca. 8 – 10 kyr, characterised by 2 periods of increased aridity (ca. 30 – 26.5 kyr and 21 – 19.5 kyr) (Petherick et al. 2008a). A growing number of records from across the Southern Hemisphere e.g. New Zealand (Suggate and Almond 2003; Alloway et al. 2007; Newnham et al. 2007a), Chile (Denton et al. 1999b), Antarctica (Röthlisberger et al. 2002; EPICA 2006) and Australia (Smith 2009) also show evidence that the LGM encompassed a longer period of time than traditionally accepted, and was not uniformly cool and dry. As such, it is suggested that the early onset of the termination of the LGC in the Southern Hemisphere occurred from ca. 35 – 30 kyr, and was possibly driven by summer insolation minima in the high southern latitudes. In addition, trace element compositions of inorganic deposits archived in the TOR sediments were used to provenance dust to continental source areas. Such provenance allowed the reconstruction of major dust transport pathways to NSI during the LGM, which in turn allowed associated synoptic scale conditions to be suggested. The position and strength of dust transport pathways for eastern Australia during the termination of the LGC provides new insights into climatic conditions in the region. Our reconstructions show that latitudinal westerly wind circulation was dominant during the LGM in two phases, suggesting an equatorward shift in the position of the westerlies. Westerlies appeared to shift poleward during the interstadial period, when southeasterly trade winds became more influential on NSI.

The Theosophy of Jacob Boehme, German Protestant Mystic, and the Development of His Ideas in the Works of His English Disciples, Dr. John Pordage and Mrs. Jane Leade.

Harris, Brian — 2008-11-21T00:00:00Z

This thesis, in the spirit of the History of Ideas, seeks to bring together in one work the basic ideas contained in the theosophy of the German Protestant mystic Jacob Boehme, and to subsequently trace how his ideas were developed and changed in the works of the English disciples, Dr. John Pordage and Mrs. Jane Leade. Recent studies have shown the pervasive influence of Jacob Boehmes writings in the early modern period, especially in England; Charles I, John Milton, William Law, and later, William Blake, were some of the important figures who came under its spell. Because of the radical nature of Boehmes message, that God had personally revealed universal secrets to him, Boehmes life in Germany became marred by persecution from the established religious hegemony. Religious radicals in England were also harried and pursued. During the interregnum, the Presbyterian and Anglican authority tried to uphold their power against a disintegrating political circumstance. They attacked with vigour any religious movement they deemed to be heretical and subversive to their authority. Under such pressure many religious groups sought refuge from the dictates of any religious jurisdiction. During the periods of intense political upheaval they looked for security in their own interpretations of the scriptures, and especially in the quietude of turning away from the world to the impulses given by the inner spirit. Overall, mystically inclined religious dissidents tended to long for some pansophic revelation that would rise above the worldly tumult and provide a resolution to long unanswered questions and aspirations. Boehme, for example, experienced the political and religious upheaval in Germany which led to the 30 Years War. He meditated upon the question of the cause of evil in the world. This endeavour led him to examine fundamental Christian questions, about what is God? What is the nature of God? How does God cause the things that are to come into existence? He sought to know these truths before he could answer the puzzle of why evil obtains. Because he could not find answers to these questions in orthodox canons he trawled far and wide - even to the works of antiquity, to bring in many topics he thought relevant into the pansophic net. Consequently, in his eclectic reach we will find reference to Neoplatonism, Alchemy, the Kabbalah, Astrology, Magia and Angelology, subjects that were always an undercurrent to the mystical in religion, now in Boehmes theosophy brought to the fore. This thesis will identify and draw out from the mass of Jacob Boehmes works the core ideas which underpin his theosophy. In bringing these subjects to the foreground the thesis points to the source, or tradition, of the core idea. Once we have established Jacob Boehmes core ideas and pointed to his sources it is contended that it will be possible then to approach and understand the doctrines of Dr. John Pordage and Mrs. Jane Leade in a clearer light. The thesis is divided into 6 chapters, but following the pattern set by the preceding remarks, the basic framework of the thesis is in three parts. Part one examines some detail of Boehmes life where it is deemed necessary for a framing exposition. The thesis is not concerned with an encyclopaedic reach of Boehmes biographical story but gives many details relevant for an understanding of his theosophy. Similarly, the thesis looks at the life and doctrines of former writers on mystical topics who are known to have been influential and it notes what aspect of their work was taken up by Boehme. Thus, armed with enough biographical detail and with an exposition of the major influences upon him, the thesis moves on to examine the core ideas of Jacob Boehmes theosophy. In part two, once the main planks of Jacob Boehmes are clearly delineated, the thesis moves on to discuss the reception of Boehmes theosophy in England, and how it impacted on the life and works of Dr. John Pordage. Pordage would go on to champion aspects of the Boehme canon to his own detriment. For a time he was able to combine his duties as an Anglican Rector with his preference for religious experimentation of a mystical nature. Unable to achieve the spontaneous theophanies encountered by the mentor Boehme, Pordage sought divine revelation in encounters with mediums, in trance-inducing rhythmic singing and dancing, in the rigours of self-deprivation, and in the company of eccentric characters who pretended to divine preference. These pursuits were obviously outside the scope of his Anglican duties and brought ill repute to him when such experiments were made known to the ecclesiastic authority. He was brought to book and sacked from the living of the Rectory at Bradfield. After exile from the church, Pordage continued on to live in seclusion, gathering about him a small number of devotees who were drawn to him by his undoubted personal magnetism and by the power of his preaching ability. As he got older he began to shun the world and to spend many days in introspective journeys where his spirit soared from his body in mystical flights of fancy. The thesis details biographical events relevant to an understanding of Pordages thought and then moves on to discuss the main ideas presented in Pordages work, the Theosophia Mystica, published by Jane Leade and her associates, three years after his death. The discussion seeks to establish the core ideas of Pordages theosophy. Another aim of the thesis is to ascertain to what degree Pordage took up Boehmes ideas, and alternately, to show where he parted from them and why. In the third section of the thesis there is an exposition of Mrs. Jane Leades works. After Pordage was rusticated he remained for a time in the vicinity of Bradfield, but thereafter moved to London. It was in London that Jane Leade was drawn to his little band of private worshippers. Mrs. Leade was destitute following the death of her husband. She had decided that her future lay in promoting Gods works. As a chiliast she was especially concerned with the advent of the New Jerusalem. She believed that such an event was imminent and Gods kingdom would be established on Earth. Eventually she was invited to join the Pordage household and she cast her lot with them. Together they worked upon a religious manifesto and eventually decided to publish their exhortations to the world under the banner of what they called the Philadelphian Society. The Philadelphian Society was a loose-knit federation of like minded people in England and on the Continent who were interested in Jacob Boehmes theosophy and the mystical in religion in general. When Pordage died Mrs. Leade assumed the leadership. She published many tracts of a religious nature during this time. Her purpose was to exhort those of lesser religious experience to strive to become of higher standing in the Lord. She wrote that she had achieved numerous preferments from God. She even contended that she had stood before Gods presence in order that she might understand His purpose. In this way she thought she had become like a General. Her duties sought to martial the righteous armies back to their spiritual home. The thesis will notice her drive towards a thoroughgoing Neoplatonism as she eschewed all worldly gifts, honours and riches - counting them as of nothing compared to the glory of spiritual life. Her other-worldly encounters were often induced by what she called daily dyings, which meant, in practice, a regime of austere asceticism; meaning that the body was denied the comforts of repose, sleep and sustenance. She put into practice the extreme negative aspects of a Neoplatonic doctrine that the body and the things of this world were worthless. In similar fashion to the elder Pordage, she was never happier than in the state when she thought her spirit left her body to prepare for her return to the eternal spiritual home. Accordingly, the thesis discusses the major planks of Mrs. Leades ideas as she extolled them in her writings. The exposition shows how she followed in the steps of her mentor John Pordage and where she added emphasis here and there with her own stamp. Overall, it is noticed how the framework of her ideas was compiled through her association with John Pordage; and how, through his mentorship, she reached back to the maker, Jacob Boehme.

The Thirty-two Major Marks of a Buddha

Stiebritz, Rudi — 2008-11-21T00:00:00Z

The research of this dissertation focuses on the Thirty-two Major Marks (Sanskrit laksana, Pali lakkhana) of the physical body of the Buddha. According to Indian tradition these marks are already present at birth of any Great Personality or Great Being (Mahiipurusa), and they are also characteristics of the Buddha. Although the special marks (laksana) of a Great Being (Mahiipurusa) were present in many earlier Indian traditions even before the Buddha, all Buddhist schools developed this important concept further and the Thirty-two Marks of a Great Man (Sanskrit Mahiipurusalaksana, Pali Mahiipurisalakkhana) became a very important aspect of the buddha concept in all Buddhist traditions. The main purpose of this study is to investigate and compare the variations and differences in the descriptions and understanding of the Major Marks of the Great Man (Mahiipuvusa) as given in the texts of the early Theravada Buddhist tradition and the later Mahayana tradition of Northern India and Tibet. Such comparative research, using the Theravada and Tibetan sources, has to my knowledge not been done up tp date and it is the first attempt to analyse the descriptions of bodily marks of the Buddha, their karmic causes and the differences in their relative importance for the Theravada and the Tibetan Buddhist traditions. This research throws additional light on the development of the concept of a Great Man in Buddhist traditions and contributes to a better understanding of the Buddhist ideas of human perfection and the iconography of the image of a Great Man, an Enlightened Being (buddha) in different Buddhist schools.

The Tourism Transformation Process: An inquiry into the three main process phases

Char-lee McLennan — 2012-04-26T00:00:00Z

Over the last century, many industrialised countries around the world responded to the declines in traditional industries, such as agriculture and manufacturing, by transforming into service economies (Cali, Ellis & Willem te Velde, 2008; Gallouj, 2002). Indeed, governments have actively pursued tourism as an economic development strategy (Akama & Kieti, 2007; Lourens, 2007; Ritchie & Crouch, 2000). As a result, tourism has changed and transformed the nature of the world’s economies. In Australia, many regions have had to restructure their economies towards tourism to avoid declines (Sorenson & Epps, 2005). However, regions have often had to pursue transformation on their own, lacking external federal and state government support, in addition to the internal mechanisms for gaining advice, funding and the decision-making tools required for dealing appropriately with the process (Kelly, 2002). As a result, many regions have pursued inappropriate policies and, with a lack of long-term focus on development, there have been significant negative impacts upon local economies, communities and the environment (Alexandra & Riddington, 2007). Consequently, there is a need to increase knowledge surrounding the long-term tourism change process to aid decision-makers. This long-term process of change, whereby an economy restructures from one economic sector to another owing to institutional change, has been termed transformation (Seliger, 2002). The literature suggests that institutions are important underlying factors in tourism development and require further research (Agarwal, 2002; Breakey, 2005; Onkvisit & Shaw, 1986; Saarinen, 2004), particularly across the stages of development (Scott, 2003). Existing indicators used to measure institutions in a tourism destination are currently under-developed and there is little evidence of how institutions interact with structures across the transformation process (McLennan, Ruhanen, Ritchie & Pham, 2011). The tourism literature postulates that a destinations structure is defined by the triple bottom line, or its economic, social and environmental characteristics (Carter, 2004; Prideaux, 2000; Martens & Rotmans, 2005; McDonald, 2006). Understanding such elements and their relationship to the tourism industry is critical for comprehending how tourism develops over the long-term. Currently, there is a lack of clarity surrounding how tourism relates and contributes to long-run economic, social and environmental changes (Alexandra & Riddington, 2007; Papatheodorou, 1999; Parrilla & Font, 2007). There are still clear theoretical gaps within the current understanding of long-range planning for tourism destinations. Consequently, this research aims to identify and examine relationships and changes in a regions structures and institutions as the tourism system transforms from an inception to an urban system. It achieves this by using a mixed-model research design aimed at comparing and contrasting structural and institutional factors in three tourism regions at different stages of tourism and economic development. Specifically, the three regions represent the inception, construction and urbanisation stage of transformation. The mixed-method research design incorporated surveying, index development, generalised ordinal logistic regression and counter-factual scenario planning. The findings of this research suggest that the relationship between tourism and the economy, society and environment is far more complex and, while some factors are dependent upon the stage of transformation, the relationships vary and are interrelated. In particular, this research found a positive relationship between tourism and the economy at all three stages of transformation, yet no significant difference between the regions’ societies or how tourism affected these societies. This infers that the impact of tourism on societies is complicated by its dependence on the geographic location and cultural context of the region. However, the impact of tourism on the environment was heterogeneous across the stages of transformation. While the inception region had the most positive environmental rating, tourism had the greatest negative impact on the environment in this region, most likely owing to the inception region being less economically developed and more environmentally preserved than the other two regions. In contrast, the urban region had the least positive environmental rating, yet tourism had a positive relationship with the environment. Indeed, other factors besides tourism were determined to be significantly affecting the urban regions environment. In terms of institutions, there was no difference between the three regions tourism industry’s management processes, performance measurement and benchmarking processes. There were few institutional differences between the tourism industry and other industries in the inception region, but several significant differences were found for the construction region and more were found for the urban region. This suggests that, across the development spectrum, the tourism industry adapts to become ‘smarter’ and more agile and adaptable than other industries in a region across the transformation process. This thesis advances transformation theory as a tool for understanding the tourism development process and investigates the phenomenon from a cyclical time perspective, which has been under-investigated within the tourism literature. This research contributes a suite of structural and institutional indexes that can be used by tourism managers and planners to monitor, evaluate and benchmark the tourism industry across time. This research also has implications for tourism planning, development and policy makers, particularly long-range planning at the local level.

THE TRANSVERSOTREMATIDAE WITENBERG, 1944 (PLATYHELMINTHES: DIGENEA): RICHNESS AND ABUNDANCE IN THE INDO-WEST PACIFIC

Janet Hunter — 2011-11-01T00:00:00Z

Janet Hunter 33649603 Abstract The Transversotrematidae Witenberg, 1944 is one of the smallest families of trematodes. The adult habitat in the recess beneath the scales of marine and freshwater fishes is unique among digeneans. The group was first identified as a larval form from freshwater streams in India (Soparkar, 1924). The first adult marine transversotrematid was found from an unidentified host from the Red Sea, was described and established as a subfamily (spelled Transversotreminae) by Witenberg (1944) and raised to family status by Yamaguti (1953). The first transversotrematid from Australian waters was discovered in Moreton Bay by Manter (1970). The goal of this study was to investigate the richness, host specificity and biogeographical distribution of this family in the Indo-West Pacific region involving the collection of as many host/parasite/location combinations as possible throughout the region with a major focus on the Great Barrier Reef. A total of 2808 individuals from 321 species from 61 fish families were inspected. Infections were found on 610 individuals from 15 fish families from the Great Barrier Reef (Heron Island and Lizard Island), Moreton Bay (Queensland), the Maldives, New Caledonia, Ningaloo (Western Australia) and Palau. The simple morphology of transversotrematids and apparently equivocal characters meant that morphological analysis alone was insufficient to separate species. Sequence analyses of the internal transcribed spacer ITS2 rDNA were used to explore the integrity of the species and their evolution and biogeographic range. Wherever possible, sequences from multiple replicates from as many host/parasite/location combinations were examined to explore intraspecific or interspecific variation. Sequences of ITS1 rDNA and 28S rDNA from specimens from a complex of species associated with mullid fishes corroborated the information generated from the ITS2 data. Multivariate analyses of the morphometric data placed the species in the same groups as the molecular data had done. Molecular analysis identified the presence of three complexes of cryptic species of Transversotrema: one of four species from mullid fishes; the second of two species from labroid fishes from Heron Island and Ningaloo WA and a species from haemulid and lethrinid fishes from Lizard Island; the third of 11 species from multiple fish families from Moreton Bay, southern Queensland, Heron Island and Lizard Island, Great Barrier Reef, the Maldives, New Caledonia, Ningaloo WA and Palau. The number of described species from the Indo-Pacific region has increased from two to 19. The richness and complexity, host and biogeographical range of the Transversotrematidae in the Indo–West Pacific are discussed.

The treatment of acquired conductive deafness and management of congenital hereditary sensorineural deafness in the dog

Sommerlad, Susan Florence — 2013-01-26T20:19:18Z

The trials of frother evaluation for industrial scale use

Comley, Brigitte Angela — 2013-01-21T15:59:06Z