The post-harvest physiology of sugarbeet (Beta vulgaris) roots was studied during controlled atmosphere (CA) storage at 35° and 50°F. Zero, 3, 6 and 10% carbon dioxide and 5% oxygen concentrations were employed to investigate the most beneficial concentrations of gases. Under the experimental conditions beets were stored successfully for 200 days. The maximum beneficial effects of CA were observed under 6% carbon dioxide and 5% oxygen at 35°F. Regardless of storage temperatures , sucrose retention was highest in the beets stored under CA, compared to conventional refrigeration (CR). Other beneficial effects include less hydrolysis of sucrose to reducing sugars and a decrease in raffinose accumulation. Fungal growth and sprouting were also inhibited significantly, under CA. In the second phase of the studies, investigations were conducted on sugarbeets to study the effects of different levels of nitrogen fertilizer on the optimum CA storage at 40°F. Regardless of the level of nitrogen fertilization, the beets stored under CA demonstrated beneficial effects as described earlier. In addition, respiration, measured on the whole beets, and amino nitrogen content of the beets were lower in the CA-stored beets than those stored under CR. Accumulation of citric acid and succinic acid was significant in the CA-stored beets.

It is of crucial importance to identify and disseminate effective treatments for paediatric obsessive-compulsive disorder (OCD). OCD is time-consuming and distressing, and can substantially disable functioning at school, at home, and with peers (Piacentini, 2003). Children who do not receive treatment are at risk of psychological difficulties in adulthood, including continued OCD, clinical anxiety and depression, personality disorders, and social maladjustment (Wewetzer et al., 2001). Two-thirds of adult cases of OCD develop in childhood, and adults with OCD have lower employment, poorer academic achievement, and lower marital rates compared to non-OCD adults (Hollander et al., 1996; Koran, 2000; Lensi et al., 1996; Steketee, 1993). The distressing nature of OCD in childhood, accompanying psychosocial impairment and risk of future psychopathology, underscore the need to identify effective treatments. The primary aim of this thesis was to expand knowledge of evidence-based treatments for paediatric OCD. A mixed-methodology approach was employed to examine key issues in this area. The first study used meta-analytic methodology to determine the evidence supporting available treatments for paediatric OCD. An extensive literature search revealed over 100 published reports of treatments, encompassing a broad array of theoretical approaches and treatment strategies. Examples of treatments used for paediatric OCD included psychodynamic therapy, pharmacotherapy, cognitive-behavioural therapy (CBT), hypnosis, family therapy, immunotherapy, and homeopathy. / Study 1 comprised the first known meta-analysis of randomised, controlled treatment trials (RCTs) for paediatric OCD. Included studies were limited to RCTs as they are the most scientifically valid means for determining treatment efficacy and provide a more accurate estimate of treatment effect by removing error variance associated with confounding variables. The literature search identified 13 RCTs containing 10 pharmacotherapy to control comparisons (N = 1016) and 5 CBT to control comparisons (N = 161). Random effects modelling yielded statistically significant pooled effect size (ES) estimates for pharmacotherapy (ES = 0.48, 95% CI = 0.36 to 0.61, p < .00001) and CBT (ES = 1.45, 95% CI = 0.68 to 2.22, p =.002). The results support the efficacy of CBT and pharmacotherapy, and confirm these approaches as the only two evidence-based treatments for paediatric OCD. Implications and suggestions for future research are discussed. The effectiveness of CBT provided impetus to further examine this treatment. Group CBT is an understudied treatment modality among children with OCD. It was hypothesised that group CBT would possess efficacy because of the effectiveness of individual CBT for children with OCD, the demonstrated effectiveness of group CBT among adults with OCD, the practical and therapeutic advantages afforded by a group treatment approach, and the embeddedness of the approach in robust psychological theory. The aim of the second study was to evaluate the efficacy of group CBT. The study comprised the largest known conducted randomised, placebo-controlled trial of group CBT for paediatric OCD. / Twenty-two children and adolescents with a primary diagnosis of OCD were randomly assigned to a 12-week program of group CBT or a credible psychological placebo. Children were assessed at baseline, end of treatment, and at 1 month follow-up. Outcome measures included the Children’s Yale-Brown Obsessive-Compulsive Scale, global measures of OCD severity, Children’s Depression Inventory, and parent- and child-rated measures of psychosocial functioning. An intention-to-treat analysis revealed that children in the group CBT condition had statistically significantly lower levels of symptomatology at posttreatment and follow-up compared to children in the placebo condition. Analysis of clinical significance showed that 91% of children that received CBT were ‘recovered’ or ‘improved’ at follow-up, whereas 73% of children in the placebo condition were ‘unchanged’. Effect size analysis using Cohen’s d derived an effect of 1.14 and 1.20 at posttreatment and follow-up, respectively. These effects are comparable to results from studies of individual CBT. This study supported group CBT as an effective treatment modality for paediatric OCD and demonstrated that the effect extends beyond placebo and nonspecific treatment factors. In addition to treatment efficacy, the inherent worth of a treatment lies in its adoption by the relevant clinical population. Children with OCD are known to be secretive and embarrassed about symptoms, and there is often a long delay between onset of symptoms and treatment-seeking (Simonds & Elliot, 2001). An important observation during the course of conducting the RCT was that a high rate (39%) of eligible families declined participation. / This led to the question, "What barriers prevent participation in group CBT for paediatric OCD?" Qualitative methodology was employed to address this research question. Eligible families that had declined participation in the RCT were contacted and invited to participate in semi-structured interviews that explored reasons for non-participation and positive and negative perceptions of group CBT. The average time between non-participation and interview was 1.33 years (SD = 3 months). Data were collected from nine families and thematic analysis methodology was utilised to identify emergent themes. Failure to participate was predicted by practical and attitudinal barriers. Practical barriers included a lack of time, distance, severity of OCD symptoms, financial, and child physical health. Attitudinal barriers included child embarrassment about OCD symptoms, child belief that therapy would be ineffective, fear of the social aspect of the group, lack of previous success with psychology, lack of trust in strangers, parental concern about the structure of the group, denial of a problem, and ‘not being ready for it’. Attitudinal barriers more frequently predicted treatment non-participation. Positive and negative perceptions of this treatment modality were informative. Parents showed no differences in preference for individual or group CBT. An important finding was that 56% of the children had not received treatment since parental expression of interest in the group CBT program. Application of the findings to methods that promote service utilisation is discussed.

Master of Science / Haematopoietic stem cell transplantation (HSCT) is a complicated and high-risk procedure used to cure disease or stop the spread of disease in a range of cancers. HSCT carries a high incidence of mortality and is associated with distressing short and long-term side effects. In addition, patients remain at risk of recurrence or mortality years after transplantation. Therefore, patients undergoing HSCT have been found to experience significant emotional and psychosocial distress because of the trauma associated with treatment. The literature suggests that about 50% of HSCT patients will experience clinical levels of distress. Carers and family members play an important role in caring for these ill patients in the short and long-term. Major role changes and financial stressors are experienced in many families, adding to the burden of care. However, very little is known about the rates of psychopathology in carers of HSCT patients. Due to the arduous nature of HSCT, psycho-educational programmes have been developed by major transplant centres and hospitals in order to provide HSCT patients and their families with information on the treatment process, side effects, risks, and long-term outcomes. Research on patient education in oncology has shown that providing patients and carers with information about their illness and treatment reduces anxiety and distress. To date, there have been no empirical evaluations to support the use of education programmes for HSCT patients. While it could be assumed that information would be helpful in reducing anxiety and depression in HSCT as it is in oncology generally, the information provided to these patients is usually more confronting and therefore, may be less reassuring. Thus, it is not known whether providing patients with education about HSCT reduces patient and carer distress or whether it might actually increase adverse outcomes. The aim of the present study was to evaluate the rates and correlates of distress in carers and patients and examine the effect of a psychoeducation programme for patients undergoing HSCT and their carers on knowledge, distress, information satisfaction, social support and caregiver burden. A randomised control trial was conducted to provide empirical data in relation to the latter aim. The following hypotheses were proposed. Firstly, it was hypothesised that patients and carers who received the education programme would have higher levels of knowledge, not evidenced in a group waiting to receive the programme. Secondly, it was hypothesised that the education program would not lead to increased anxiety and depressive symptoms. Thirdly, patients who know more about their condition would be the least distressed. As predicted, this study found high levels of distress, particularly in carers. Higher patient distress was related to having more concern about one’s illness and experiencing more symptoms. Education was effective in increasing patient and carer knowledge. Importantly there were no adverse effects of knowledge and greater patient knowledge following the education program was associated with less distress, although there was no direct effect of education on distress. Future research should aim to identify what aspects of the education program are helpful to patients. Finally, support interventions such as CBT are needed to help patients and carers, in particular, cope with the high levels of distress inherent in the HSCT experience.

The increased work of breathing associated with intense cycling has been identified as a factor that may negatively affect cycling performance. The aerodynamic position, abnormal respiratory mechanics either at rest or during exercise, and the development of a tachypnoeic breathing pattern are factors known to increase the work of breathing. Breathing pattern retraining aims to decrease the work of breathing by delaying the onset of dynamic hyperinflation and the recruitment of accessory breathing muscles. To date no studies have investigated the performance, physiological and perceptual consequences of manipulating breathing pattern in trained cyclists. Purpose: The aim of the present study was to investigate the effect of breathing pattern retraining on 20-km time trial performance and respiratory and metabolic measures in competitive cyclists. Method: Twenty-four competitive male cyclists (age 37.7 ± 8.6 years, mean ± SD; peak 4.34 ± 0.47 L·min-1) were match paired on 20-km time trial performance and assigned at random to either an intervention group (breathing pattern retraining; N = 12) or control group (N = 12). 20-km time trial performance, pulmonary function and the physiological and perceptual response during a maximal incremental cycle step test were assessed pre- and post-intervention. The intervention group underwent four weeks of specific breathing pattern retraining using exercises designed to reduce dynamic hyperinflation and optimise respiratory mechanics. The control group attended the laboratory once a week during this period and performed a 10 minute sub-maximal ride wearing a biofeedback breathing harness. The control group was led to believe the purpose for their participation was to investigate the effect that maximal exercise had on breathing pattern, and to test the reliability of the breathing harness. There was no attempt to modify the breathing pattern of the control group. Data were analysed using an MS Excel spreadsheet designed for statistical analysis. The uncertainty in the effect was expressed as 90% confidence limits and a smallest worthwhile effect of 1.0% was assumed. Results: The intervention group showed substantial improvements in 20-km time trial performance (-1.5 ± 1.1%) and incremental power (3.2 ± 3%). Additionally, breathing frequency (-13.2 ± 8.9%; -9.5 ± 8.4%), tidal volume (10.6 ± 8.5%; 9.4 ± 7.6%), inspiratory time (10.1 ± 8%; 9.4 ± 7.7%), breathing RPE (-30 ± 33.9%; -24.7 ± 28.1%) and leg RPE (-27.9 ± 38.5%; -24.7 ± 28.2%) were all positively affected at lactate threshold and lactate turn point. No positive changes were observed in the control group for 20-km time trial performance (0.0 ± 1.0%), incremental power (-1.4 ± 3.5%), breathing frequency (-1.6 ± 8.0%; -2.0 ± 7.9%), tidal volume (0.9 ± 7.2%; 2.9 ± 9.4%), breathing RPE (16.1 ± 50.2%, 24.8 ± 43%) or leg RPE (13.4 ± 39.6%; 19.9 ± 43.2%) . Conclusion: These results provide evidence of the performance enhancing effect of four weeks of breathing pattern retraining in cyclists. Furthermore, they suggest breathing pattern can be retrained to exhibit a controlled pattern, without a tachypnoeic shift, during high intensity cycling. Additionally, these results indicate breathing pattern retraining attenuates the respiratory and peripheral perceived effort during incremental exercise. Key words: Breathing pattern disorders, retraining, blood stealing, cycling, performance, power output, respiratory mechanics, perceived exertion, 20km-TT

Introduction: Embolic agents are used to block blood flow of hypervascular tumours, ultimately resulting in target tissue necrosis. However, this therapy is limited by the formation of new blood vessels within the tumour, a process known as angiogenesis. Targeting angiogenesis led to the discovery of anti-angiogenic factors, large molecular weight proteins that can block the angiogenic process. The aim of this research is development of poly (vinyl alcohol) (PVA) aqueous solutions that cross-link in situ to form a hydrogel that functions as an embolic agent for delivery of macromolecular drugs. Methods: PVA (14 kDa, 83% hydrolysed), functionalised by 7 acrylamide groups per chain, was used to prepare 10, 15, and 20wt% non-degradable hydrogels, cured by UV or redox initiation. Structural properties were characterised and the release of FITCDextran (20kDa) was quantified. Degradable networks were then prepared by attaching to PVA (83% and 98 % hydrolysed) ester linkages with an acrylate end group. The effect on degradation profiles was assessed by varying parameters such as macromer concentration, cross-linking density, polymer backbone and curing method. To further enhance the technology, radiopaque degradable PVA was synthesised, and degradation profiles were determined. Cell growth inhibition of modified PVA and degradable products were also investigated. Results: Redox initiation resulted in non-degradable PVA networks of well-controlled structural properties. Increasing the solid content from 10 to 20wt% prolonged the release time from few hours to ~ 2 days but had no effect on the percent release, with only a maximum release of 65% achieved. Ester attachment to the PVA allowed flexibility in designing networks of variable swelling behaviors and degradation times allowing ease of tailoring for specific clinical requirements. Synthesis of radiopaque degradable PVA hydrogels was successful without affecting the polymer solubility in water or its ability to polymerize by redox. This suggested that this novel hydrogel is a potential liquid embolic with enhanced X-ray visibility. Degradable products had negligible cytotoxicity. Conclusion: Novel non-degradable and radiopaque degradable PVA hydrogels cured by redox initiation were developed in this research. The developed PVA hydrogels showed characteristics in vitro that are desirable for the in vivo application as release systems for anti-angiogenic factors.

The central question posed in this thesis is why has the Queensland model of workers' compensation been so enduring? The legislation remained largely intact from 1916 until 2001, with the exception of the years from 1996 to 1998. This was so despite the fact the central feature of a state-controlled monopoly that underpinned this model was always potentially divisive in line with the variances between liberal-conservative traditions and social-democratic ideals that subsisted in broader political culture. In addressing this question of longevity, this thesis explores the capacity of an initially contentious piece of legislation to draw strong support from former opponents, and the argument is put forward that it is best explained through the development and operation of a policy community that fostered a shared set of core values relative to broad workers' compensation policy preferences. These core values were compulsory state monopoly, no fault insurance and full access to common law. Thus, the longevity of the legislation is attributed to the continued support by key stakeholders of these core values. The thesis also demonstrates that policy community relations deteriorated during the 1990s as governments responded to broader political pressures precipitated by reform agendas. Inconsistencies in core values and policy outcomes for each stakeholder emerged as governments attempted to assert unprecedented control over the direction of workers' compensation in order to meet broader political goals. The legislation was threatened as relations within the policy community proved unsustainable when existing core values were contested.

Christian Parent Controlled (CPC) Schools, which commenced in the 1960s, are a relatively small, but growing component of the non-government schooling sector in Australia. In 2001, they enrolled over 22 000 students in 85 schools. Very little research has been conducted on the values and practices of CPC schools and while these schools frequently assert that they promote explicitly Christian values, their foundational values have not previously been identified or recorded. This research identifies the key foundational values which are characteristic of these schools and examines the extent to which these values continue to influence the prevailing practices of these schools. Consideration is given to the implications of the relationship between foundational values and prevailing practices for the identity, development and leadership of CPC schools in Australia. The ability of these schools to articulate their foundational values and consider their prevailing practices in the light of these values should enhance their ability to understand their heritage, assess their current situation and plan their future. The research found that in general, prevailing practices in these schools give faithful expression to the foundational values; however, the research also identified a number of areas where CPC schools struggle to engage consistently with these values. As a result of this study, recommendations are proposed to assist national and school-based leadership in their strategic planning for the maintenance of these values and the future of these schools.

Background: Physiological studies have shown that many preterm infants and infants with chronic lung disease may suffer chronic hypoxaemia, which possibly leads to poor growth and development. Anecdotal reports indicate that there is a drive to increase the oxygen saturation target range to a higher level in these infants due primarily to perceived benefits derived from clinical experience and from uncontrolled observational studies of babies discharged on home oxygen. Objective The BOOST (Benefits Of Oxygen Saturation Targeting) trial is the first randomised trial to assess the long-term benefits and harms of two different oxygen saturation target ranges. Methods: BOOST was a multicentre, double blinded, randomised controlled trial that enrolled 358 infants born at less than 30 weeks� gestation who remained oxygen-dependent at 32 weeks postmenstrual age. They were randomly assigned to target either a functional oxygen saturation range of 91-94% (standard or control group) or 95-98% (higher or treatment group). The primary outcomes were growth and neurodevelopmental measures at 12 months corrected age. Secondary outcomes included length of hospital stay, retinopathy of prematurity, health service utilisation, parental stress, and infant temperament. Results: Prognostic baseline characteristics did not differ between the two groups. Mean birth weight and gestational age of enrolled infants was 917g and 26.5 weeks respectively. The rate of antenatal corticosteroid use was 83%.

Sliding mode control (SMC) has been successfully applied to many practical control problems due to its attractive features such as invariance to matched uncertainties. The characteristic feature of a continuous-time SMC system is that sliding mode occurs on a prescribed manifold, where switching control is employed to maintain the state on the surface. When a sliding mode is realized, the system exhibits some superior robustness properties with respect to external matched uncertainties. However, the realization of the ideal sliding mode requires switching with an infinite frequency. Control algorithms are now commonly implemented in digital electronics due to the increasingly affordable microprocessor hardware although the essential conceptual framework of the feedback design still remains to be in the continuous-time domain. Discrete sliding mode control has been extensively studied to address some basic questions associated with the sliding mode control of discrete-time systems with relatively low switching frequencies. However, the complex dynamical behaviours due to discretization in continuous-time SMC systems have not yet been fully explored. In this thesis, the discretization behaviours of SMC systems are investigated. In particular, one of the most frequently used discretization schemes for digital controller implementation, the zero-order-holder discretization, is studied. First, single-input SMC systems are discretized, stability and boundary conditions of the digitized SMC systems are derived. Furthermore, some inherent dynamical properties such as periodic phenomenon, of the discretized SMC systems are studied. We also explored the discretization behaviours of the disturbed SMC systems. Their steady-state behaviours are discussed using a symbolic dynamics approach under the constant and periodic matched uncertainties. Next, discretized high-order SMC systems and sliding mode based observers are explored using the same analysis method. At last, the thesis investigates discretization effects on the SMC systems with multiple inputs. Some conditions are first derived for ensuring the

Preventive care for the elderly originated with a study in Great Britain in 1964 that reported a large number of unmet health needs in the elderly and advocated early intervention. Subsequent randomised controlled trials (RCT) used a broad assessment of health including bio-medical, functional, psychological and social /environmental components but inconsistently demonstrated improved outcome for the elderly. 'Health checks' were introduced for all patients in British general practice in 1990. European and American models of care evolved similarly and justify a multidisciplinary team assessment, thorough training of assessment staff and medical supervision of recommendations. Two literature reviews published in 2000 have not reported sound evidence in favour of health assessments. Medicare funding of health assessments for the Australians aged 75 years and over was introduced in November 1999. A protocol for conducting 75+ Health Assessment (75+ HA) was developed and a pilot study was conducted in Yarrawonga in 1995 to initiate Australian research of this model of care. A RCT in the Adelaide Western Division of General Practice tested this model of care. The intervention group (n=50) had two 75+ HA one year apart. The control group (n=50) was left to usual care and had a 75+ HA one year later. Demographic data and the Short Form-36 were used to ensure both groups were comparable. Primary outcome measures did not demonstrate statistically significant reduction in problems nor mortality in the intervention (75+ HA) group compared to the control group. Significant improvements in secondary outcome measures in the intervention group were in self-rated health, depression score and decreased numbers reporting falls. 75+ HAs have been widely taken up by Australian general practitioners. It is no longer possible to conduct a RCT due to the inability to find a legitimate control group. Recommendations arising form this literature review and RCT include; evaluation studies of 75+ HA, concentration on a functional model of health and that nurses or allied health professionals should conduct the assessment in the elderly person's home. A consistent framework for analysis of 75+ HA is proposed. The elderly can be conceived to occupy one of 3 cohorts defined by their function state: No impairment of Activities of Daily Living (ADL), Impairment of Instrumental ADL only or Impairment of Basic ADL. The elderly without ADL impairment have not been demonstrated to benefit from 75+ HA and should be left to access the acute care stream of health services. The most disabled elderly with Basic ADL impairment have not consistently been shown to benefit from 75+ HA probably because they need a more intense level of community care. They should have Care Plans renewed regularly, as tested in the Australian Coordinated Care Trials. The cohort with Instrumental ADL impairment only seems most likely to benefit from annual 75+ HA. An evaluation of screening the elderly for Instrumental and Basic ADL impairment and providing appropriate services for each cohort is recommended. / Thesis (M.D.)--Department of General Practice, 2001.