Does psychological stress mediate social deprivation in tooth loss?

It is unclear which theoretical dimension of psychological stress affects health status. We hypothesized that both distress and coping mediate the relationship between socio-economic position and tooth loss. Cross-sectional data from 2915 middle-aged adults evaluated retention of < 20 teeth, behaviors, psychological stress, and sociodemographic characteristics. Principal components analysis of the Perceived Stress Scale (PSS) extracted 'distress' (a = 0.85) and 'coping' (a =0.83) factors, consistent with theory. Hierarchical entry of explanatory variables into age- and sex-adjusted logistic regression models estimated odds ratios (OR) and 95% confidence intervals [95% CI] for retention of < 20 teeth. Analysis of the separate contributions of distress and coping revealed a significant main effect of coping (OR = 0.7 [95% CI = 0.7-0.8]), but no effect for distress (OR = 1.0 [95% CI = 0.9-1.1]) or for the interaction of coping and distress. Behavior and psychological stress only modestly attenuated socio-economic inequality in retention of < 20 teeth, providing evidence to support a mediating role of coping.

Water uptake of aerosols with a focus on seeded aerosols and instrumentation techniques

This thesis focuses on the volatile and hygroscopic properties of mixed aerosol species. In particular, the influence organic species of varying solubility have upon seed aerosols. Aerosol studies were conducted at the Paul Scherrer Institut Laboratory for Atmospheric Chemistry (PSI-LAC, Villigen, Switzerland) and at the Queensland University of Technology International Laboratory for Air Quality and Health (QUT-ILAQH, Brisbane, Australia). The primary measurement tool employed in this program was the Volatilisation and Hygroscopicity Tandem Differential Mobility Analyser (VHTDMA - Johnson et al. 2004). This system was initially developed at QUT within the ILAQH and was completely re-developed as part of this project (see Section 1.4 for a description of this process). The new VHTDMA was deployed to the PSI-LAC where an analysis of the volatile and hygroscopic properties of ammonium sulphate seeds coated with organic species formed from the photo-oxidation of á-pinene was conducted. This investigation was driven by a desire to understand the influence of atmospherically prevalent organics upon water uptake by material with cloud forming capabilities. Of particular note from this campaign were observed influences of partially soluble organic coatings upon inorganic ammonium sulphate seeds above and below their deliquescence relative humidity (DRH). Above the DRH of the seed increasing the volume fraction of the organic component was shown to reduce the water uptake of the mixed particle. Below the DRH the organic was shown to activate the water uptake of the seed. This was the first time this effect had been observed for á-pinene derived SOA. In contrast with the simulated aerosols generated at the PSI-LAC a case study of the volatile and hygroscopic properties of diesel emissions was undertaken. During this stage of the project ternary nucleation was shown, for the first time, to be one of the processes involved in formation of diesel particulate matter. Furthermore, these particles were shown to be coated with a volatile hydrophobic material which prevented the water uptake of the highly hygroscopic material below. This result was a first and indicated that previous studies into the hygroscopicity of diesel emission had erroneously reported the particles to be hydrophobic. Both of these results contradict the previously upheld Zdanovksii-Stokes-Robinson (ZSR) additive rule for water uptake by mixed species. This is an important contribution as it adds to the weight of evidence that limits the validity of this rule.

Sustainable subdivisions – review of technologies for integrated water services

Water is a current major global, national and local issue. Historic drought and unprecedented restriction levels are now substantially influencing almost all Australia’s major cities. Residential design and adoption of appropriate technologies plays a key role in urban water efficiency. This project, the first of the CRC-CI Sustainable subdivisions program with a focus on water, explores the existing technologies available for sustainable suburbs.

Effect of height of bridge above water on salt deposition levels

Maintenance of bridge structures is a major issue for the Queensland Department of Main Roads. In the previous phase of this CRC project an initial approach was made towards the development of a program for lifetime prediction of metallic bridge components. This involved the analysis of five representative bridge structures with respect to salt deposition (a major contributor to metallic corrosion) to determine common elements to be used as “cases” - those defined for buildings are not applicable. The five bridges analysed included the Gladstone Port Access Road Overpass, Stewart Road Overpass, South Johnstone River Bridge, Johnson Creek Bridge and the Ward River Bridge.

Post-traumatic stress disorder in response to HIV infection

This study investigated the psychological impact of HIV infection through assessment of posttraumatic stress disorder in response to HIV infection. Sixty-one HIV-positive homosexual/bisexual men were assessed for posttraumatic stress disorder in response to HIV infection (PTSD-HIV) using a modified PTSD module of the DIS-III-R. Thirty percent met criteria for a syndrome of posttraumatic stress disorder in response to HIV diagnosis (PTSD-HIV). In over one-third of the PTSD cases, the disorder had an onset greater than 6 months after initial HIV infection diagnosis. PTSD-HIV was associated with other psychiatric diagnoses, particularly the development of first episodes of major depression after HIV infection diagnosis. PTSD-HIV was significantly associated with a pre-HIV history of PTSD from other causes, and other pre-HIV psychiatric disorders and neuroticism scores, indicating a similarity with findings in studies of PTSD from other causes. The findings from this preliminary study suggest that a PTSD response to HIV diagnosis has clinical validity and requires further investigation in this population and other medically ill groups. The results support the inclusion of the diagnosis of life-threatening illness as a traumatic incident that may lead to a posttraumatic stress disorder, which is consistent with the DSM-IV criteria.

Anisotropy of spin relaxation of water protons in cartilage and tendon

Transverse spin relaxation rates of water protons in articular cartilage and tendon depend on the orientation of the tissue relative to the applied static magnetic field. This complicates the interpretation of magnetic resonance images of these tissues. At the same time, relaxation data can provide information about their organisation and microstructure. We present a theoretical analysis of the anisotropy of spin relaxation of water protons observed in fully hydrated cartilage. We demonstrate that the anisotropy of transverse relaxation is due almost entirely to intramolecular dipolar coupling modulated by a specific mode of slow molecular motion: the diffusion of water molecules in the hydration shell of a collagen fibre around the fibre, such that the molecular director remains perpendicular to the fibre. The theoretical anisotropy arising from this mechanism follows the “magic-angle” dependence observed in magnetic-resonance measurements of cartilage and tendon and is in good agreement with the available experimental results. We discuss the implications of the theoretical findings for MRI of ordered collagenous tissues.

Improvements in sustainable energy and water practice in the food processing industry : an in depth analysis of the manufacture of Ghee at the Butter Producers' Cooperative Federation Limited, Brisbane

This thesis is a documented energy audit and long term study of energy and water reduction in a ghee factory. Global production of ghee exceeds 4 million tonnes annually. The factory in this study refines dairy products by non-traditional centrifugal separation and produces 99.9% pure, canned, crystallised Anhydrous Milk Fat (Ghee). Ghee is traditionally made by batch processing methods. The traditional method is less efficient, than centrifugal separation. An in depth systematic investigation was conducted of each item of major equipment including; ammonia refrigeration, a steam boiler, canning equipment, pumps, heat exchangers and compressed air were all fine-tuned. Continuous monitoring of electrical usage showed that not every initiative worked, others had pay back periods of less than a year. In 1994-95 energy consumption was 6,582GJ and in 2003-04 it was 5,552GJ down 16% for a similar output. A significant reduction in water usage was achieved by reducing the airflow in the refrigeration evaporative condensers to match the refrigeration load. Water usage has fallen 68% from18ML in 1994-95 to 5.78ML in 2003-04. The methods reported in this thesis could be applied to other industries, which have similar equipment, and other ghee manufacturers.

Emerging urban futures, land, water, infrastructure

This paper will examine the intersection of design research and problem‐based teaching through the process and outcomes of a four year long ARC funded research project: the Emerging Futures Project. Sustainability is central to the project; in its overall content as well as in the broad aim of determining better outcomes for urban consolidation.   

Does occupational stress really matter? A study of psychological climate and stress on job satisfaction in Thailand

This study explored the prediction of psychological climate and stresses on job satisfaction in non U.S. setting. A total of 450 surveys were sent to 11 organisations in Thailand and employees were asked to fill out the survey. The first hypothesis that positive psychological climate dimensions predicted lower level of stresses among Thai employees was partially accepted. Further regression analysis tested second hypothesis that positive psychological climate dimensions and low level of stresses predict job satisfaction among Thai employees. Contrary to expectation, only stress variables predicted job satisfaction. Thai culture influence was discussed.

Clypeotheca, a new skeletal structure in scleractinian corals : a potential stress indicator

Physiological responses to environmental stress are increasingly well studied in scleractinian corals. This work reports a new stress-related skeletal structure we term clypeotheca. Clypeotheca was observed in several livecollected common reef-building coral genera and a two to three kya subfossil specimen from Heron Reef, Great Barrier Reef and consists of an epitheca-like skeletal wall that seals over the surface of parts of the corallum in areas of stress or damage. It appears to form from a coordinated process wherein neighboring polyps and adjoining coenosarc seal themselves off from the surrounding environment as they contract and die. Clypeotheca forms from inward skeletal centripetal growth at the edges of corallites and by the merging of flange-like outgrowths that surround individual spines over the surface of the coenosteum. Microstructurally, the merged flanges are similar to upsidedown dissepiments and true epitheca. Clypeotheca is interpreted primarily as a response to stress that may help protect the colony from invasion of unhealthy tissues by parasites or disease by retracting tissues in areas that have become unhealthy for the polyps. Identification of skeletal responses of corals to environmental stress may enable the frequency of certain types of environmental stress to be documented in past environments. Such data may be important for understanding the nature of reef dynamics through intervals of climate change and for monitoring the effects of possible anthropogenic stress in modern coral reef habitats.