7 resultados para Cinnamon-vented piha

em Deakin Research Online - Australia


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The pathogen Phytophthora cinnamomi causes extensive 'dieback' of Australian native vegetation. This study investigated the distribution of infection in an area of significant sclerophyll vegetation in Australia. It aimed to determine the relationship of infection to site variables and to develop a predictive model of infection. Site variables recorded at 50 study sites included aspect, slope, altitude, proximity to road and road characteristics, soil profile characteristics and vegetation attributes. Soil and plant tissues were assayed for the presence of the pathogen. A geographical information systyem (GIS) was employed to provide accurate estimations of spatial variables and develop a predictive model for the distribution of P. cinnamomi. The pathogen was isolated from 76% of the study sites. Of the 17 site variables initially investigated during the study a logistic regression model identified only two, elevation and sun-index, as significant in determining the probability of infection. The presence of P. cinnamomi infection was negatively associated with elevation and positively associated with sun-index. The model predicted that up to 74% of the study area (11 875 ha) had a high probability of being affected by P. cinnamomi. However, the present areas of infection were small, providing an opportunity for management to minimize spread into highly susceptible uninvaded areas.

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Phytophthora cinnamomi (Cinnamon fungus) is a pathogenic soil fungus which infects plant communities along the south-eastern coast of Australia, and the south-western corner of Western Australia. The symptoms of this disease include chlorosis, death of branches (ie. ‘dieback’), retarded growth and the eventual death of infected plants. This leads to devastating effects upon plant communities by altering both the structural and floristic characteristics of these communities. Small mammal species are dependent on specific features of their habitat such as vegetation structure and floristics. This thesis investigated alterations to the habitat of the insectivorous marsupial mouse, Antechinus stuartii, due to the presence of P. cinnamomi. The study was undertaken in an area of an open forest in the Brisbane Ranges, Victoria. Significant changes were found in both the floristic composition and structure of the vegetation at study sites infected with P, cinnamomi, compared to uninfected sites. The habitat utilization by A. stuartii of uninfected and infected vegetation was investigated using live trapping and radio-telemetric techniques. Capture rates were higher at sites uninfected by P. cinnamomi, and both male and females selected areas free from infection. Home range areas of males were significantly larger than those of females as assessed by telemetry. Both sexes spent a high proportion of time in areas dominated by Xanthorrhoea australis (Austral grass tree). There were significant relationships between the abundance of A. stuartii and the denseness of vegetation above 1 metre in height, and in particular, the proportion of cover afforded by X. australis. There were no significant differences in the cover of Eucalyptus spp. between uninfected and infected sites, but there were significantly more nest hollows in infected areas. The abundance of invertebrates was examined using pitfall traps. There were no significant differences in the abundance of the larger invertebrate taxa at infected and uninfected sites, but higher abundances of some micro-invertebrate groups in infected areas were recorded. The most likely factors considered to be influential in the habitat selection of A. stuartii were vegetation structure, and the presence of X. australis. To assess whether these factors were important the leaves of X. australis were removed with a brushcutter, to mimic the early effects of infection with P. cinnamomi. Animals did not respond to the alteration of vegetation structure in the short term (3-4 days). Longer-term experiments are required to assess the habitat utilization of A. stuartii at different periods following habitat manipulation. The implications of the presence of P. cinnamomi on the conservation of fauna are discussed. The destructive nature of the pathogen, and the slow rate of recovery from the disease, means that P. cinnamomi can be considered a threatening process to plant communities and the fauna that reside within that habitat. Future management of this disease within natural areas must therefore be cognisant of the potential of P. cinnamomi to significantly affect faunal as well as vegetative communities.

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The thesis proposes a theory of the "relevance" and "significance" of cultures to human beings and the world, and a methodology to measure these. It applies architecture (as a culture) as the generator of thought and as an experimental case. A case study applies the theory and methodology in practice and contains as its main material a history of ideas in contemporary architecture.

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Background: Complementary and alternative medicine (CAM) is common in patients with chronic disease such as diabetes mellitus. The primary objective of the study was to determine the overall prevalence and type of CAM use in individuals with diabetes mellitus (DM) in Western Sydney and to compare the prevalence and factors associated with CAM use with the literature.

Methods: A multicenter cross-sectional study was undertaken using a self-completed questionnaire distributed to patients with DM attending a public hospital and specialist endocrinology clinics in the region. The type of DM and pattern of CAM utilisation were analyzed.

Results: Sixty nine people responded to the questionnaire: age range of 18-75 years during a twelve week collection period. Overall, 32 respondents with diabetes were using some form of CAM, resulting in a utilisation rate of 46.3%. Twenty of the 32 CAM users used CAM specifically to treat their diabetes accounting for 28.9% of the respondent sample population. Multivitamins (40%), cinnamon, Co-enzyme q10 and prayer were the most frequently used CAM modalities. There was no significant difference between males and females, age range, income or diabetes complications between CAM and non-CAM users. (p values each > 0.05) The factor most significantly associated with CAM usage was being born overseas (p = 0.044).

Conclusions: Almost half the respondents (46.3%) used CAM: 28% used CAM specifically to treat their diabetes. Individuals born overseas were significantly more likely to use CAM than those born in Australia. Other factors such as age, gender, wealth and duration of living with diabetes were not associated with higher rate of CAM usage.

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The study focuses on developing novel probiotic yogurts containing spices with acceptable sensory properties, therapeutic levels of probiotics and with beneficial antioxidant capacity. Eight types of yogurts with added spice oleoresins (cardamom, cinnamon and nutmeg) and probiotics [Lactobacillus acidophilus strain 5(LA5), or Bifidobacterium animalisssp.Lactis (Bb12)] were produced. Two successive consumer sensory taste panels (n = 54) using a nine point hedonic scale were conducted to evaluate the acceptability of the yogurts. Viable counts of probiotics and antioxidant capacity of yogurt samples at 1, 7, 14 and 28 days of storage at 4 °C were monitored. The probiotic-yogurt products containing spices showed good sensory properties, with the best results obtained with cardamom oleoresin (with LA5 or Bb12). The presence of spice oleoresins (cardamom, nutmeg and cinnamon) did not affect the probiotic population (LA5or Bb12) in yogurt during 4 weeks of refrigerated storage. The antioxidant capacity (with LA5or Bb12) over the storage period was also maintained.

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Glutathione (GSH) has a crucial role in cellular signaling and antioxidant defenses either by reacting directly with reactive oxygen or nitrogen species or by acting as an essential cofactor for GSH S-transferases and glutathione peroxidases. GSH acting in concert with its dependent enzymes, known as the glutathione system, is responsible for the detoxification of reactive oxygen and nitrogen species (ROS/RNS) and electrophiles produced by xenobiotics. Adequate levels of GSH are essential for the optimal functioning of the immune system in general and T cell activation and differentiation in particular. GSH is a ubiquitous regulator of the cell cycle per se. GSH also has crucial functions in the brain as an antioxidant, neuromodulator, neurotransmitter, and enabler of neuron survival. Depletion of GSH leads to exacerbation of damage by oxidative and nitrosative stress; hypernitrosylation; increased levels of proinflammatory mediators and inflammatory potential; dysfunctions of intracellular signaling networks, e.g., p53, nuclear factor-κB, and Janus kinases; decreased cell proliferation and DNA synthesis; inactivation of complex I of the electron transport chain; activation of cytochrome c and the apoptotic machinery; blockade of the methionine cycle; and compromised epigenetic regulation of gene expression. As such, GSH depletion has marked consequences for the homeostatic control of the immune system, oxidative and nitrosative stress (O&NS) pathways, regulation of energy production, and mitochondrial survival as well. GSH depletion and concomitant increase in O&NS and mitochondrial dysfunctions play a role in the pathophysiology of diverse neuroimmune disorders, including depression, myalgic encephalomyelitis/chronic fatigue syndrome and Parkinson’s disease, suggesting that depleted GSH is an integral part of these diseases. Therapeutical interventions that aim to increase GSH concentrations in vivo include N-acetyl cysteine; Nrf-2 activation via hyperbaric oxygen therapy; dimethyl fumarate; phytochemicals, including curcumin, resveratrol, and cinnamon; and folate supplementation.