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The present study investigated the causal predominance of cognition on anxiety, depression, paranoia, phobia and somatic concern over three time waves of self reported data measured every six months over one year, of 145 cases experiencing their first episodes of psychosis. In turn the symptoms of anxiety, depression, paranoia, phobia and somatic concern were examined for their cross-influential effects on cognition. Cognition was examined under a causal predominance hypothesis as the lead symptom because of its influence recognised in the literature under the neurodevelopmental hypothesis. These longitudinal effects were examined using structural equation modelling. Prior to this investigation, the research was able to demonstrate a stable 6-factor measurement model with these symptoms between two independent samples of early psychosis cases that met guidelines of treatment under the Australian national early psychosis treatment guidelines. This measurement model demonstrated good internal reliability and construct validity. Most symptoms over each time wave had a "domino effect" where the symptom prior to the next wave of assessment had an influence. This is known as a mediation effect. Somatic concern and depression demonstrated a "snow ball" or direct effect where the extent of the condition at time one influenced directly the condition at time three. Structural models, which examined the cross-influential effect between cognition and the other symptoms, demonstrated an effect between paranoia and cognition. This effect demonstrated that paranoia at Time 2 (i.e., 6 months after stabilisation of symptoms), had a crossinfluential effect on cognition at Time 3 (ie, 12 months after stabilisation of symptoms). / It was argued that poor thinking styles that lead to distortion in feelings of mistrust evident in the paranoia symptom, in turn led to deterioration in cognition. Other symptoms did not demonstrate a cross influential effect. Previous research suggesting that symptoms act independently of each other over time supports the results of independence of the other symptoms. Further research was suggested by linking different levels of psychosis research of the aetiological factors (e.g. genetic factors), neuropathology (e.g., reduced synapse density) and phenomenology (e.g., positive and negative symptoms) into an integrative framework. It was suggested that structural equation modelling as exemplified in the thesis could be used as a technique to examine how these differing levels could be investigated under a unified theory of psychosis based upon the neurodevelopmental hypothesis.

The production of reactive oxygen species by mitochondria is implicated in mitochondrial dysfunction associated with a range of diseases and ageing. In addition, reactive oxygen species produced by mitochondria are involved in redox signalling pathways that modulate a number of cell processes. Mitochondria targeted antioxidants comprised of an antioxidant moiety linked to a lipophilic triphenylphosphonium cation have recently been used to decrease oxidative damage to mitochondria and to investigate the involvement of mitochondrial reactive oxygen species in redox signalling. These lipophilic cations are selectively accumulated by mitochondria within cells due to the mitochondria membrane potential. This thesis presents the synthesis and characterization of mitochondria targeted membrane uncoupler, cyclic nitroxide and alkyl thionitrite derivatives, all of which had the potential to influence reactive oxygen species. The biological analysis of these compounds is also presented. A triphenylphosphonium derivative of the membrane uncoupler 2,4-dinitrophenol (DNP) was anticipated to act as a self regulating protonophore. The DNP moiety would influence the scale of the membrane potential while the triphenylphosphonium cation would respond to the membrane potential. These two factors would combine so that as the membrane potential was dissipated by the uncoupler, the phosphonium cation would be released from the mitochondria and the effect of the uncoupler would thereby be nullified until the membrane potential had increased again. The compound was prepared by nitration of 3-(4-hydroxyphenyl)propyl triphenylphosphonium bromide. An untargeted derivative was also prepared by nitration of 3-(4-hydroxyphenyl)-1-propanol. Unfortunately, while this compound had appropriate acidity and lipophilicity to act as a membrane uncoupler, and did enter mitochondria in response to the membrane potential, it did not act as an uncoupler. A chemically stable targeted cyclic nitroxide based on Tempol was prepared following literature procedure, although other synthetic routes were also trialled. This compound was shown to concentrate in mitochondria in response to the membrane potential, was reduced by ubiquinol of the coenzyme Q pool, acted as a superoxide dismutase mimetic, and protected membranes against lipid peroxidation. A mitochondria targeted thionitrite or nitric oxide (NO) donor was anticipated to exhibit an effect on respiration at low oxygen concentrations as the released NO interacted with aspects of the respiratory chain. The alkyl thionitrites were synthesised from appropriate thiol precursors, several of which were prepared. Two targeted alkyl thionitrites were prepared with primary or tertiary carbon arrays next to the thionitrite functionality. Another targeted thionitrite, based on S-nitroso-N-acetylpenicillamine (SNAP), was also prepared. These compounds were difficult to characterise because of issues surrounding their stability. However, modified high resolution positive ion electrospray mass spectrometry in combination with HPLC and NMR was used to identify the compounds and to gauge the purity of the samples. Initial biological investigations verified that the primary alkylthionitrite derivative accumulated in mitochondria, released NO, and had an effect on respiration at low oxygen concentrations.

1 v. (various pagings) : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (D. Sc.)--University of Adelaide, Dept. of Pathology, 1993

1 v. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1992

Thesis (Ph. D.)--University of California, San Diego and San Diego State University, 2007. / Includes bibliographical references (p. 129-140).

Studies were conducted in 2005 and 2006 at Baxter Orchard, Great Smoky Mountains National Park, Tennessee to optimize survival of Sasajiscymnus tsugae (St) (Sasaji and McClure) released as eggs on eastern hemlock, Tsuga canadensis (L.) Carriere, for biological control of Adelges tsugae (HWA) Annand. Studies investigated annual abundance and seasonality of HWA lifestages, weekly field and laboratory survival of St, and survival of St egg cohorts of various ages and densities. HWA was determined to be bivoltine on eastern hemlock in Tennessee with an aestivation period between July and October. Lifestages preferred as food by St were present from February through June with peak abundance ca. late March. Weekly survival of St placed in the field and laboratory as eggs was investigated. Less than 10% of St eggs placed in the field between 8 February to 22 March survived because of freezing field temperatures. Survival rose to 30-40% on 30 March and persisted at that level until 7 June, when survival decreased below 10% due to scarcity of food. Studies were conducted to investigate the effect of St egg density on survival of St. Four densities of St eggs (50, 100, 150, and 200 eggs/container) were placed in the field and laboratory. In the laboratory, survival was higher for lower densities of St eggs, implying cannibalism increases with density. Three egg age classes (0-2, 3-5, and 6-8 days old) were used to test the effect of St egg age on survival. St in field cages showed poor survival, likely due to freezing temperatures. However, the oldest (6-8 day) age class showed significantly greater survival in the field than the younger age classes. The two oldest age classes showed significantly greater survival than the youngest (0-2 day) age class in the laboratory. Results of multiple studies over two years support the release of St eggs to enhance biological control efforts against HWA. Studies showed St established as eggs in the field could successfully develop into adults. Survival of St from egg releases is highest when St eggs are released between late March and May, in low densities, and in older age classes.

In recent years, a large commercial grower of African violets (Saintpaulia ionantha Wendl.) in middle Tennessee has experienced epidemics of Corynespora leaf spot caused by Corynespora cassiicola (Berk. & Curt.) Wei (Alan Windham, personal communication). Symptoms of Corynespora leaf spot include rapidly expanding circular lesions on the surface of the leaves and petioles. The disease occurs in propagation material and mature plants of S. ionantha which result in thousands of plants being discarded daily. The objectives of this research were to: 1) determine if irrigation methods affected disease severity, 2) to determine if fungicidal spray intervals could be extended beyond the recommended two week interval, and 3) to determine if leaf age affects the susceptibility of S. ionantha to C. cassiicola. Three irrigation treatments (drip, mist, and ebb & flow) were evaluated for their effect on disease severity of C. cassiicola. Over a seven week period, plants were observed for the presence of lesions on leaves and petioles. This experiment was repeated four times with four to six replications per repetition. Disease severity was not significantly different in the three irrigation treatments in reducing the spread of C. cassiicola. Three fungicides (propiconazole, thiophanate-methyl, chlorothalonil) and a water control were applied to symptomatic S. ionantha. Leaves were collected for eight weeks. Overall, leaves sprayed with the thiophanate-methyl treatment produced the lowest amount of sporulation and isolate growth, but no treatment was effective in inhibiting the growth of C. cassiicola in S. ionantha tissue. The effect of leaf age on disease susceptibility was evaluated using three stages of S. ionantha leaves: juvenile, mature, and senescing. Lesion size was larger on juvenile and senescing leaves than on mature leaves.