This research focuses on studying the microstructure of alloy 909, its susceptibility to oxidation at elevated temperatures (~700°C) and substrate coatings compatibility with high velocity oxy fuel (HVOF) sprayed oxidation resistance coatings. The characterization work involved in studying the microstructure of Incoloy 909 at three heat treated conditions namely solution treated condition (ST), commercially recommended solution heat treated and aged condition (STA), and solution treated and over aged condition (STOA) using optical microscopy, analytical scanning electron microscopy, and analytical transmission electron microscopy. The oxidation susceptibility were investigated at elevated temperatures of bare and coated alloy 909 substrates by subjecting test materials to isothermal and thermal cycle testing. The microstructure of alloy 909 in the ST condition showed only the presence of blocky Laves phase. The Laves phase in this alloy is a well known for its grain pinning effect that prevents excessive grain growth. In the STA condition, the microstructure revealed the presence of fine gamma prime, intergranular and intragranular Laves phase and occasionally gamma prime precipitates orienting in a platelet form ready to transition into the epsilon phase. In the STOA condition, the microstructure consisted of Laves phase in inter and intragranular locations, and a copious amount of Widmanstatten type epsilon phase. Incoloy 909 was observed to form oxide scales in both isothermal and cyclic thermal exposures, the oxide scale consisted of distinct outer and inner scales in the micrographs. The comparison base alloy (alloyl 718) used in this study surprisingly did not show any visible presence of oxide scale after 1000 hour exposure at ~700°C. Three coatings (CoNiCrAlY, 718 , and NiAl) were sprayed on alloy 909 and alloy 718 test coupons using the HVOF process to investigate the compatibility of the coatings with the substrate. The test results points out that all the coatings were compatible with 718 substrate and only one coating (NiAl) was found compatible with the Alloy 909 substrate, indicating that the coatings that are compatible with one substrate may not be compatible with another alloy within the same family of alloys.

Abstract Introduction. The biopsychosocial model has developed over the last forty years since Melzac and Wall first stated the need to broaden the biomedical view of pain mechanisms. The biopsychosocial concept is now central in contemporary understanding of human health and functioning in general, and pain in particular. An extensive biopsychosocial literature on low back pain has emerged since the paradigm shift of nearly thirty years ago, and has been reflected in evidence-based clinical practice guidelines on musculoskeletal pain. The estimation of prognosis from an episode of low back pain is particularly important to clinicians, patients, employers and third party payers. The instruments currently available however, quantify prognostic factors from a biomedical perspective, rather than the contemporary biopsychosocial model. The successful development of the biopsychosocial instrument, reported in this thesis, fills this gap in measurement, and affirms the hypothesis advanced that it is feasible to develop a valid and reliable multidimensional index to estimate prognosis from a range of biopsychosocial variables, in low back pain. The thesis describes; • A review of pain mediation/modulation • A review of the literature on the biopsychosocial model to identify a range of variables for investigation • Consideration of different outcome measures as the gold standard criterion measure • The development of the BPIP, a novel biopsychosocial instrument designed for eventual clinical use, as a means of considering non specific low back pain from a biopsychosocial perspective, and informing prognosis in patients who do not have diagnosable levels of psychopathology Methods. The Biopsychosocial Index of Prognosis (BPIP) was developed from a content map derived from the International Classification of Functioning, Health and Disease (ICF) for use in non specific low back pain of variable duration. A prototype BPIP instrument was drafted, and a peer review process resulted in item reduction. The prototype BPIP instrument was then subjected to a twenty four hour test-retest assessment of stability, prior to assessment of the prototype BPIP’s validity and internal consistency. Questionnaire packs containing the prototype BPIP instrument, a range of other measurement instruments, an informed consent form and an instruction sheet were then issued. The data were captured at baseline, six weeks, and again at twelve weeks. Recruitment of respondents was originally intended to capture a homogeneous cohort drawn from general (medical) practice. Recruitment difficulties however resulted in two distinct cohorts, a larger Australian cohort (n = 91) and a smaller New Zealand cohort (n = 27). The larger Australian group was utilised as an elucidation cohort, and the smaller New Zealand cohort was treated as a small prospective validation of the BPIP. Item reduction was undertaken and resulted in an ordinal scale for correlation with the Roland and Morris Disability Index, the criterion measure. The resulting twenty four item BPIP scale was tested for internal consistency in both the Australian and New Zealand cohorts. The baseline data from the Australian elucidation cohort were then assessed for concurrent, predictive and construct validity against the twelve week data from The Roland and Morris Disability Index (RDQ), the selected criterion measure. The New Zealand cohort was treated as a small prospective validation of the BPIP scale, with the baseline data from the BPIP correlated with the change score from the baseline to twelve weeks, of the RDQ. Analysis was undertaken using the SPSS statistical package. Results. Correlation analysis of the baseline BPIP Australian data with the twelve week RDQ Australian data resulted in reducing the prototype scale to questions which correlated at or above 0.3, a total of twenty four questions were retained. Reliability coefficients for internal consistency of the twenty four item BPIP scale were: The Australian cohort, Cronbach’s Alpha = 0.8736. The New Zealand cohort, Cronbach’s Alpha = 0.8628. A further review of the correlation analysis of the baseline BPIP Australian data with twelve week RDQ Australian data for items that correlated at or above 0.4 resulted in further item reduction of the BPIP to twelve questions. Following this further item reduction, reliability coefficients for internal consistency were: The Australian cohort, Cronbach’s Alpha = 0.875. The New Zealand cohort, Cronbach’s Alpha = 0.776. Regression analysis of the Australian cohort based on the twelve item scale demonstrated that 61.7% of the variance in the RDQ score at twelve weeks was accounted for by the BPIP scale, with p = 0.0005. Regression analysis of the change score of the RDQ with the twelve item BPIP in the New Zealand cohort demonstrated that 78.2% of the variance in RDQ scores was accounted for by the BPIP scale, with p = 0.006. Forty five point five percent of the Australian cohort improved by more than 30%, (the proposed minimal clinically important difference of the RDQ), whilst 76.9% of the New Zealand cohort improved more than thirty percent. In a post hoc analysis of the Orebro data, the longer 25 item questionnaire accounted for 97.8% of the variance in the New Zealand cohort. Conclusion. The initial hypothesis that it would be feasible to develop a valid and reliable multidimensional instrument from a range of biopsychosocial variables into a valid instrument for estimating the prognosis of an episode of low back pain is supported by the results. The utility of a biopsychosocial instrument for routine clinical use lies in the potential to predict prognosis. As low back pain is typically a recurrent problem, information on both prognosis for recovery from episodes, and the likelihood of recurrences would be helpful to both clinician and patient. For the patient, a well communicated prognosis helps assure the patient about their future, reduces uncertainty about their pain, and establishes treatment goals within the domain of informed consent. From the clinician’s perspective, a prognostic approach shifts the focus from the pain history to future outcomes and provides a context for considering how risks of future pain and dysfunction may be reduced. The BPIP scale is a biopsychosocial, prognostic instrument, which accounts for a high degree of the variance in the RDQ scores in both cohorts. Pain amelioration and functional improvement are the two key aspects of prognosis which the BPIP has been demonstrated to be both valid and reliable in predicting at the clinically important three month time point from baseline assessment. The BPIP has been demonstrated in these cohorts, to provide a reliable estimate of prognosis from a biopsychosocial perspective. The reliability of the shortened BPIP scale remained acceptable, and allowed for the scale to be contained on a single A4 page, potentially increasing the clinical utility of the instrument. When BPIP score fails to change over time, psychosocial screening and intervention may be indicated. Future work will include further validation in other subgroups and clinical environments, identification of cut points for BPIP scores, and the performance of comparative studies of the relative value of different purported prognostic indices. The BPIP is the first instrument developed to specifically to estimate prognosis from an episode of low back pain, in primary care, within the contemporary biopsychosocial model.

Power consumption is a critical design issue in embedded processors. As part of our low power processor design project, this thesis work aims to reduce power consumption on two typical processor components: Register File (RF), and Arithmetic and Logic Unit (ALU). Register File is one of the most power hungry components in the processor, consuming about 20% of the processor power. The ALU is the working horse in the processor, responsible for almost all basic computing operations. Although ALU does not consume as high power as the register file, we observe that it can be power intensive in terms of power dissipation per silicon area unit and may result in a thermal hot spot in the processor. Existing approaches to reduce power on the register file and ALU are effective. However, most of them either entail extensive hardware design efforts, or require a significant amount of work on post-compilation software code modification. The approaches proposed in this thesis avoid such problems. We only customize the internal structure of the processor components and keep the components’ interface to other system parts intact, so that the customization to a component is transparent to its external hardware design and no modification/alteration to other hardware components or to the software code is required. This customization strategy is well suitable to our whole low power processor design project and can be applied to any customization of an existing system for a given application. We have applied our customization approaches to a set of benchmarks in a variety of application domains. Our experimental results show that the power savings on register file are in a range from 18.8% to 45.5%, an average of 29.7% register file power can be saved. For the arithmetic and logic unit, the power savings are from 43.5% to 49.6% and the average saving is 46.9% as compared to the original designs. We also combine the customization of both the ALU and the register file. With the customizing of the ALU and the register file simultaneously, the processor power consumption can be reduced from 3.9% to 10.1%; on average, 6.44% processor power can be saved. Most importantly, the power saving achievement is at the cost of neither hardware complexity nor processor performance, and the implementation is extremely straightforward and can be easily incorporated into a processor design environment, such as ASIPMeister (a design tool, to automatically generate a VHDL model for application specificinstruction set processors) used in our research.

Background and Aim: The applicability of internationally-accepted infection control guidelines in rural Indonesia is questionable due to differences in resources availability and local contexts. Infection control barriers specific to rural Indonesia therefore need to be identified to assist in developing targeted infection control programs that are resource- and context-appropriate at the institutional, regional and national levels. Methods: This mixed methods study of ten healthcare facilities (hospitals and clinics, public and private) in a rural Indonesian district, all with severely limited resources, explored clinical practices in four areas: intravenous therapy, antibiotic usage, instrument reprocessing and hand hygiene. The quantitative methods used included univariate, multivariate and survival analyses of primary and secondary clinical data. The qualitative methods included a grounded theory analysis of observations, short and in-depth interviews and focus group discussion data. These two components of the study were synthesised to ascertain the magnitude and underlying factors of healthcare-associated infection risks and barriers to infection control programs. Findings: Inappropriate clinical practices caused excessive and unrecognised risks of primary bloodstream infection, surgical site infection, blood borne virus infection, and the development and spread of multi-resistant bacteria. The four diverse clinical practice areas exhibited common and interwoven underlying factors, which were: healthcare workers?? inadequate clinical knowledge, a lack of managerial support, and cultural beliefs shared by the healthcare workers and community members that prevailed over evidence-based knowledge. Non-clinical factors from inside and outside the healthcare facilities were inter-related and cannot be separated from the ensuing clinical practice inadequacies. An analytical framework that categorises infection control barriers into clinical and non-clinical domains as well as internal and external factors is therefore proposed to ensure a comprehensive infection control program design. Conclusion: The current clinically-focused infection control programs are likely to have limited and temporary results in rural Indonesia due to barriers being in the main non-clinical in origin. An effective and sustainable infection control program needs to concurrently address basic clinical practice improvements and the underlying managerial, attitudinal and cultural barriers. This public health aspect of infection control is often neglected yet crucial for the success of any infection control program in rural Indonesia.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (M.Sc.) -- University of Adelaide, Dept. of Pharmacology, 1984. / Typescript (photocopy).

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaf 31). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Sydney, 2005. / Title from title screen (viewed 19 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Heart Research Institute, Faculty of Medicine. Degree awarded 2005; thesis submitted 2004. Includes bibliographical references. Also available in print form.

Zugl.: Ulm, Univ., Diss., 2008

Thesis (M.U.P.)--University of Michigan, Dept. of Urban Planning. / Also issued in print.