Antibiotic usage is on the rise in industrialized countries and as a result the prevalence of autoimmune and atopic diseases has risen. The use of antibiotics is connected to a depletion of the microflora located within the gastrointestinal tract. The microflora contains a variety of different bacterial species, including some that are probiotic species, Lactobacilli and Bifidobacteria, which have a beneficial effect on the host. Probiotic species of bacteria are important for immune function due to their ability to regulate oral tolerance, a state of unresponsiveness to antigens that have been introduced orally to the host. The goal of this study was to assess the effect of broad spectrum antibiotic treatment on the probiotic species Lactobacilli and the resulting effect on the induction of oral tolerization to the antigen ovalbumin. / Department of Biology

Access to abstract restricted until May 2014 / Access to thesis restricted until May 2014 / Department of Biology

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To test the hypothesis that red-osier dogwood cuttings from a more stressful edaphic environment (dry site) would have a greater salinity tolerance compared with cuttings from a less stressful environment (moist site) a greenhouse experiment was designed. Cuttings collected from three sites in southeastern Manitoba varying in edaphic conditions (moisture) were exposed to 0, 25, 50, or 100 mM NaCl in hydroponics. After four weeks of treatment, physiological parameters were measured. No differences in salinity tolerance were observed between the sites; nevertheless, this study supported previous results suggesting that red-osier dogwood can limit the transport of Na+ from the root to the shoot. To determine the presence of barriers to ion movement, the roots of red-osier dogwood exposed to NaCl were sectioned and observed using brightfield and fluorescence techniques. A modified outer cortical layer was observed suggesting the presence of an exodermis, which would be an additional barrier to Na+ and Cl- movement. Furthermore, the maturation of the endodermis and exodermis occurring closer to the root tip could also contribute to limiting the transport of Na+ to the shoot.

Master of Philosophy (MPhil) / Background: Physical deconditioning is often associated with chronic pain and is believed to be a result of gradual movement inhibition and reduction of physical activities. It is common for chronic pain sufferers to present with limited muscle extensibility and poor tolerance to physical movement. Exercises are therefore prescribed to assist in regaining muscle extensibility, strength, fitness and endurance. Of particular interest is stretch, a type of exercise aimed at increasing muscle extensibility. Stretch is commonly prescribed as part of physical rehabilitation in pain management programs, yet little is known of its effectiveness in the chronic pain population. Aim: The aim of this randomised controlled trial was to investigate the effects of a three-week stretch program on muscle extensibility and stretch tolerance in patients with chronic musculoskeletal pain. Methods: Thirty adults with pain persisting for at least three months and limited hamstring muscle extensibility were recruited from patients enrolled in a multidisciplinary pain management program at a Sydney Hospital. A within-subject design was used, with one leg of each participant randomly allocated to an experimental (stretch) condition and the other to a control (no stretch) condition. The hamstring muscles of the experimental leg were stretched for one minute a day over a three-week period, whilst the hamstring muscles of the control leg were not stretched during this time. This intervention was embedded within a pain management program and supervised by physiotherapists. Primary outcome measures were muscle extensibility and stretch tolerance, reflected by passive hip flexion angles produced with standardised and non-standardised torques, respectively. Initial measures were taken prior to the first stretch on day one and final measures were taken one to two days after the last stretch. A blinded assessor was used for all testing. Results: After three weeks of intervention, stretch did not increase muscle extensibility (mean between-group difference in hip flexion was 1 degree; 95% CI -2 to 4 degrees) but did improve stretch tolerance (mean between-group difference in hip flexion was 8 degrees; 95% CI 5 to 10 degrees). Conclusion: Three weeks of stretch increases tolerance to the discomfort associated with stretch but does not change muscle extensibility in patients with chronic musculoskeletal pain. This study provides support for the ongoing incorporation of stretch in pain management programs, where stretch may be conceptualised as a graded exposure to movement and assisting in the restoration of normal activity and function.

We develop a framework for finding robust solutions of constraint programs. Our approach is based on the notion of fault tolerance. We formalise this concept within constraint programming, extend it in several dimensions and introduce some algorithms to find robust solutions efficiently. When applying constraint programming to real world problems we often face uncertainty. Whilst reactive methods merely deal with the consequences of an unexpected change, taking a more proactive approach may guarantee a certain level of robustness. We propose to apply the fault tolerance framework, introduced in [Ginsberg 98], to constraint programming: A robust solution is one such that a small perturbation only requires a small response. We identify, define and classify a number of abstract problems related to stability within constraint satisfaction or optimisation. We propose some efficient and effective algorithms for solving these problems. We then extend this framework by allowing the repairs and perturbations themselves to be constrained. Finally, we assess the practicality of this framework on constraint satisfaction and scheduling problems.

Identifying a genetic basis for the tolerance to salinity exhibited by the resilient moss, Physcomitrella patens, could provide valuable information for use in the selection or modification of salinity tolerance in crop plants. The overall aim of the work described in this thesis was to identify, express and functionally characterise the protein products of two putative salinity tolerance genes from Physcomitrella, namely PpMdhar and PpENA1. The characterisation of PpMdhar and PpENA1 represents a two-pronged approach into investigating the salinity tolerance of Physcomitrella at the biochemical and transport level, respectively. The enzymes encoded by PpMdhars, monodehydroascorbate reductases (MDHARs), are central to the ascorbate-glutathione cycle, and recycle monodehydroascorbate molecules into the antioxidant, ascorbate. Hence, MDHARs play a part in maintaining the capacity of plant cells to remove toxic reactive oxygen species. Given that the production of reactive oxygen species is greatly increased in plants under salt stress, and that Physcomitrella is tolerant of high salt, MDHAR enzymes were expressed to determine whether they exhibit increased enzymic activity when compared with MDHARs from higher plants. The protein encoded by PpENA1 is Na⁺ transporting ATPase, which actively transports toxic Na⁺ ions across the cell membranes, and thereby minimizes the level of Na⁺ that accumulates in the cytoplasm. Thus, in contrast to the mechanism by which MDHARs may help Physcomitrella deal with the secondary effects of high salt, the PpENA1 protein could enable the moss to actively exclude Na⁺ ions, and thereby avoid cellular toxicity. A link between salinity and the transcription of PpMdhar and PpENA1 is reported here, and the function of each gene is investigated. A comprehensive characterisation of the enzymic action of expressed PpMDHAR enzymes is described, demonstrating that the biochemical mechanisms used by Physcomitrella in dealing with salt-induced reactive oxygen species are likely to be conserved with vascular plants. The physiological effects of the expression of PpENA1 are investigated via complementation experiments in yeast, and the membrane location of the protein is determined. The Na⁺ binding-sites of PpENA1 are predicted using homology modelling and amino acid residues crucial for Na⁺ transport are tested experimentally via site-directed mutagenesis. Finally, the introduction of a new, functional Na⁺ binding-site into an inactivated form of the PpENA1 protein demonstrates that a degree of control is possible over the Na⁺ binding-sites in PpENA1. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1337385 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

Master of Philosophy (MPhil) / Background: Physical deconditioning is often associated with chronic pain and is believed to be a result of gradual movement inhibition and reduction of physical activities. It is common for chronic pain sufferers to present with limited muscle extensibility and poor tolerance to physical movement. Exercises are therefore prescribed to assist in regaining muscle extensibility, strength, fitness and endurance. Of particular interest is stretch, a type of exercise aimed at increasing muscle extensibility. Stretch is commonly prescribed as part of physical rehabilitation in pain management programs, yet little is known of its effectiveness in the chronic pain population. Aim: The aim of this randomised controlled trial was to investigate the effects of a three-week stretch program on muscle extensibility and stretch tolerance in patients with chronic musculoskeletal pain. Methods: Thirty adults with pain persisting for at least three months and limited hamstring muscle extensibility were recruited from patients enrolled in a multidisciplinary pain management program at a Sydney Hospital. A within-subject design was used, with one leg of each participant randomly allocated to an experimental (stretch) condition and the other to a control (no stretch) condition. The hamstring muscles of the experimental leg were stretched for one minute a day over a three-week period, whilst the hamstring muscles of the control leg were not stretched during this time. This intervention was embedded within a pain management program and supervised by physiotherapists. Primary outcome measures were muscle extensibility and stretch tolerance, reflected by passive hip flexion angles produced with standardised and non-standardised torques, respectively. Initial measures were taken prior to the first stretch on day one and final measures were taken one to two days after the last stretch. A blinded assessor was used for all testing. Results: After three weeks of intervention, stretch did not increase muscle extensibility (mean between-group difference in hip flexion was 1 degree; 95% CI -2 to 4 degrees) but did improve stretch tolerance (mean between-group difference in hip flexion was 8 degrees; 95% CI 5 to 10 degrees). Conclusion: Three weeks of stretch increases tolerance to the discomfort associated with stretch but does not change muscle extensibility in patients with chronic musculoskeletal pain. This study provides support for the ongoing incorporation of stretch in pain management programs, where stretch may be conceptualised as a graded exposure to movement and assisting in the restoration of normal activity and function.

Identifying a genetic basis for the tolerance to salinity exhibited by the resilient moss, Physcomitrella patens, could provide valuable information for use in the selection or modification of salinity tolerance in crop plants. The overall aim of the work described in this thesis was to identify, express and functionally characterise the protein products of two putative salinity tolerance genes from Physcomitrella, namely PpMdhar and PpENA1. The characterisation of PpMdhar and PpENA1 represents a two-pronged approach into investigating the salinity tolerance of Physcomitrella at the biochemical and transport level, respectively. The enzymes encoded by PpMdhars, monodehydroascorbate reductases (MDHARs), are central to the ascorbate-glutathione cycle, and recycle monodehydroascorbate molecules into the antioxidant, ascorbate. Hence, MDHARs play a part in maintaining the capacity of plant cells to remove toxic reactive oxygen species. Given that the production of reactive oxygen species is greatly increased in plants under salt stress, and that Physcomitrella is tolerant of high salt, MDHAR enzymes were expressed to determine whether they exhibit increased enzymic activity when compared with MDHARs from higher plants. The protein encoded by PpENA1 is Na⁺ transporting ATPase, which actively transports toxic Na⁺ ions across the cell membranes, and thereby minimizes the level of Na⁺ that accumulates in the cytoplasm. Thus, in contrast to the mechanism by which MDHARs may help Physcomitrella deal with the secondary effects of high salt, the PpENA1 protein could enable the moss to actively exclude Na⁺ ions, and thereby avoid cellular toxicity. A link between salinity and the transcription of PpMdhar and PpENA1 is reported here, and the function of each gene is investigated. A comprehensive characterisation of the enzymic action of expressed PpMDHAR enzymes is described, demonstrating that the biochemical mechanisms used by Physcomitrella in dealing with salt-induced reactive oxygen species are likely to be conserved with vascular plants. The physiological effects of the expression of PpENA1 are investigated via complementation experiments in yeast, and the membrane location of the protein is determined. The Na⁺ binding-sites of PpENA1 are predicted using homology modelling and amino acid residues crucial for Na⁺ transport are tested experimentally via site-directed mutagenesis. Finally, the introduction of a new, functional Na⁺ binding-site into an inactivated form of the PpENA1 protein demonstrates that a degree of control is possible over the Na⁺ binding-sites in PpENA1. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1337385 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture, Food and Wine, 2008

Thesis (Ph. D.)--University of Wyoming, 2005. / Title from PDF title page (viewed on March 4, 2008). Includes bibliographical references (p. 95-102).