460 resultados para South Australia


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Diseases in natural ecosystems are often assumed to be less severe than those observed in domestic cropping systems due to the extensive biodiversity exhibited in wild vegetation communities. In Australia, it is this natural biodiversity that is now under threat from Phytophthora cinnamomi. The soilborne Oomycete causes severe decline of native vegetation communities in south-western Victoria, Australia, disrupting the ecological balance of native forest and heathland communities. While the effect of disease caused by P. cinnamomi on native vegetation communities in Victoria has been extensively investigated, little work has focused on the Anglesea healthlands in south-western Victoria. Nothing is known about the population structure of P. cinnamomi at Anglesea. This project was divided into two main components to investigate fundamental issues affecting the management of P. cinnamomi in the Anglesea heathlands. The first component examined the phenotypic characteristics of P. cinnamomi isolates sampled from the population at Anglesea, and compared these with isolates from other regions in Victoria, and also from Western Australia. The second component of the project investigated the effect of the fungicide phosphonate on the host response following infection by P. cinnamomi. Following soil sampling in the Anglesea heathlands, a collection of P, cinnamomi isolates was established. Morphological and physiological traits of each isolate were examined. All isolates were found to be of the A2 mating type. Variation was demonstrated among isolates in the following characteristics: radial growth rate on various nutrient media, sporangial production, and sporangial dimensions. Oogonial dimensions did not differ significantly between isolates. Morphological and physiological variation was rarely dependant on isolate origin. To examine the genetic diversity among isolates and to determine whether phenotypic variation observed was genetically based, Random Amplified Polymorphic DNA (RAPD) analyses were conducted. No significant variation was observed among isolates based on an analysis of molecular variance (AMQVA). The results are discussed in relation to population biology, and the effect of genetic variation on population structure and population dynamics. X australis, an arborescent monocotyledon indigenous to Australia, is highly susceptible to infection by P. cinnamomi. It forms an important component of the heathland vegetation community, providing habitat for native flora and fauna, A cell suspension culture system was developed to investigate the effect of the fungicide phosphonate on the host-pathogen interaction between X. australis and P. cinnamomi. This allowed the interaction between the host and the pathogen to be examined at a cellular level. Subsequently, histological studies using X. australis seedlings were undertaken to support the cellular study. Observations in the cell culture system correlated well with those in the plant. The anatomical structure of X australis roots was examined to assist in the interpretation of results of histopathological studies. The infection of single cells and roots of X. australis, and the effect of phosphonate on the interaction are described. Phosphonate application prior to inoculation with P. cinnamomi reduced the infection of cells in culture and of cells in planta. In particular, phosphonate was found to stimulate the production of phenolic material in roots of X australis seedlings and in cells in suspension cultures. In phosphonate-treated roots of X australis seedlings, the deposition of electron dense material, possibly lignin or cellulose, was observed following infection with P. cinnamomi. It is proposed that this is a significant consequence of the stimulation of plant defence pathways by the fungicide. Results of the study are discussed in terms of the implications of the findings on management of the Anglesea heathlands in Victoria, taking into account variation in pathogen morphology, pathogenicity and genotype. The mode of action of phosphonate in the plant is discussed in relation to plant physiology and biochemistry.

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Looking out from a vantage point across a large tract of forest gives a superficial impression of uniformity: the crowns of canopy trees follow the folds and contours of the landscape to provide a continuous cover of wooded vegetation. But this visual appearance belies the truth: forested landscapes are far from uniform. On closer examination, they comprise a complex mosaic of different vegetation types and and stands of different age-classes, differing structural features, and modified to a varying extent by human land-uses. Forests have a critical role in the conservation of biodiversity throughout the world (Peterken 1996; Laurance and Bierregard 1997; Lindenmayer and Franklin 2002) and a key feature contributing to their conservation value is the response of forest biota to the heterogeneity inherent in forested landscapes (Lindenmayer et al. 2006). Consequently, an understanding of the implications of landscape structure for the maintainance of species and ecological processes is an important foundation for forest management and biodiversity conservation.

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This research examined the ecological, morphometric and genetic variability of the Little Penguin (Eudyptula minor) between seven colonies in south-eastern Australia. Significant differences in breeding ecology and morphology were noted for birds between colonies. However, most colonies were genetically homogeneous with respect to each other, with the exception of the Kangaroo Island colony.

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This study examines several specific fields of activity of Australia and Japan in the areas of security, production, finance, development assistance, information, education and regional organization. Using the concept of structural power, it observes the sources of Australian and Japanese strenght in the region, the growing imbalance in the bilateral Australia-Japan relationship, and also the coexistence of affinities and differences in the development opportunities opened to the South Pacific Island Countries.

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The Hopkins River drains grazing farmland for most of its length. Nutrients and phytoplankton populations in the Hopkins Estuary are strongly affected by the hydrodynamic cycle. The findings of this research show that nutrient and chlorophyll a levels in the Hopkins Estuary are high enough to indicate that future algal problems may occur and that management of nutrients entering its catchment and improvement of river banks are of high importance.

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Bird life occurring along the Murray River was distinctly different from surrounding much drier vegetation. It was found that the presence of the Murray River, with it's associated moist Red Gum forests, provide a corridor whereby birds typically of cool climates can expand their range and occur in an arid landscape.

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Zoophycos composite ichnofabrics (ZCI) comprising two or more suites of the same form of Zoophycos are widespread and densely distributed in Early and Middle Permian (Cisuralian–Guadalupian) neritic limestones (Qixia and Maokou Formations) of palaeotropical origin in the Laibin area, Guangxi, South China. Similar ZCI also occur in neritic greywackes of glaciomarine origin from the Middle Permian (Guadalupian) Westley Park Sandstone Member (Broughton Formation) in the southern Sydney Basin, southeastern Australia. Zoophycos from both regions consists of planar spreite with major and minor lamellae and a cylindrical tunnel interpreted as a marginal tube and ⁄ or axial shaft. The cylindrical tunnel is herein considered to be an essential component of Zoophycos, and thus can be used to define and characterize the morphological variability of Zoophycos. It is suggested that the variation of spreite and major and minor lamellae originated from the different morphologies and migration manners of the cylindrical tunnel. The shallowest, shallow, middle and deepest Zoophycos tiers have been distinguished in ZCI on the basis of cross-cutting relationships, the soft-sediment deformation and the contrast in colour between Zoophycos and its host rock. The multiple tiers may represent the substrate consistency spectrum from a softground through a stiffground to a firmground.The different Zoophycos tiers may have been constructed by tracemakers of either different or the same taxonomic affinities in response to the gradual accretion and lithification of sediment layers on the seafloor. The tracemakers appeared to be very sensitive to neither climate nor lithology. The width of the planar spreiten of Zoophycos decreases slightly with the depth of tiering in ZCI

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This paper explores the palaeoclimatic significance of a fossil plant and insect record from Yarra Creek, on King Island, between Tasmania and the Australian mainland. The record dates, based upon a thermoluminescence chronology and other evidence, to Marine Isotope Stage 5 (MIS 5); the exact timing is impossible to ascertain given the resolution of the thermoluminescence results and the presence of an unconformity in the dated section. The presence of a cool-temperate rainforest flora, outside its modern range, and other independent evidence, suggest the sequence may represent the last interglacial (MIS 5e) rather than a later MIS 5 substage. Using coexistence methods that compare modern climatic ranges of the taxa in the assemblage we reconstruct independent beetle and plant based annual and seasonal temperate and precipitation parameters. The results imply the assemblage was deposited under a wetter summer climate and suggest conditions of enhanced temperature seasonality. It is probable that enhanced temperature seasonality is a methodological artefact reflecting the rarity of extremely equable climates (like King Island) in modern climate space. This would indicate a limitation of most methods of palaeoclimatic reconstruction that rely on modern datasets – it is only possible to reconstruct past climates as being within the range of values in that currently exist in modern climate space.

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The South African and Australian law regarding directors' duty of care, ski ll and diligence were influenced considerably by English precedent of the late 1800s and early 19005. Originally both jurisdictions adopted a conservative approach towards directors' duty of care, skill and diligence. This resulted in very low standards of care, skill and diligence expected of directors. In Australia, the standards of care and diligence expected of directors changed drastically with the case of Daniels v Anderson, where objective standards were used to determine a breach of directors' duty of care and diligence, and when objective standards of care and diligence were introduced in Australian corporations legislation. In this article it is submitted that if the opportunity arose for a South African court to consider whether a director is in breach of his or her common law duty of care, skill and diligence, the form of fault that will be required will be negligence as judged against the standards of a reasonable person. This means that in actual fact objective standards of care and diligence are expected of directors in South Africa. Although section 76(3) of the South African Companies Act 71 of 2008 does not introduce purely objective standards of care, skill and diligence, the section is defended in this article. It is pointed out that encouraging emerging entrepreneurs to become directors of South African companies provides justification for keeping subjective elements as part of the test to determine whether a director was in breach of his or her statutory duty of care, skill and diligence.

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Since the 1980s a wave of demutualisations have occurred across a range of industries from stock exchanges to building societies, savings and loans associations and insurers. In both Australia and South Africa this has had a marked effect on the life insurance markets which had been dominated by mutual life insurers for 150 years. This paper adopts a case study approach to analyse the key drivers of organisational change. It examines the experiences of the Australian Mutual Provident (Australia’s oldest and largest life insurance mutual) and Sanlam (the second largest mutual life office in South Africa) as they proceeded down the path to demutualisation. It suggests a complex array of factors combined to place pressure on the existing mutual structures.

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Recent corporate collapses around the world show that there are no national boundaries for these occurrences. Australian corporate collapses including HIH Insurance, One.Tel, Ansett Australia and Harris Scarfe have raised public expectations of investigation of the causes of collapses (Mirshekary, Yaftian & Cross, 2005). The main reason for the collapse of HIH was mismanagement, with an emphasis more on the directors’ personal qualities such as integrity, honesty and morality rather than tougher legislation and rules. Accounting students are our future business leaders. The teaching of ethics in the classroom to multicultural groups of students provides an opportunity to facilitate the sharing of knowledge, and to increase interaction and debate around different approaches to ethics among students from different countries.
This study uses previous literature to explain the attitudes of accounting students towards academic and business/accounting ethics at an Australian university which is a multi-campus institution undertaking programs and activities at regional, national, international levels and by distance education.
This study reports the results of cross-cultural investigations of students’ ethical perceptions on moral values, academic and accounting/business vignettes, given that all students share the same learning opportunities, knowledge of ethics and interaction with their peers and lecturers. The results indicate no significant differences in responses between the students from Australia, South Asia and East Asia.

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In Australia, numerous small mammal species have suffered extinction or severe declines in distribution and abundance following European settlement. The extent of these declines from forested areas of south-eastern Australia, however, remains poorly understood. In this paper we use sub-fossil deposits of the sooty owl (Tyto tenebricosa tenebricosa) as a tool for understanding the diversity of the small mammal palaeocommunity. These results are compared to the contemporary sooty owl diet from the same geographical region to investigate the degree of small mammal decline following European settlement. Of 28 mammal species detected in sub-fossil deposits and considered prey items of the sooty owl at the time of European settlement, only 10 species were detected in the contemporary sooty owl diet. Numerous small mammal species have not only recently suffered severe declines in distribution and abundance but have also recently undergone niche contraction, as they occupied a greater diversity of regions and habitats at the time of European settlement. For some species our understanding of their true ecological niche and ecological potential is therefore limited. The species that underwent the greatest declines occupied open habitat types or were terrestrial. The severity of decline is also likely to have resulted in severe disruption of ecosystem functions, with wide scale ecosystem consequences. There is an urgent need to improve small mammal conservation, to maintain crucial ecosystem functions performed by small mammals. It is recommended that broad-scale exotic predator control programs are conducted which may also provide suitable conditions for the re-introduction of locally extinct species.


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This article compares how two alliance partners of the United States — Australia and the Republic of Korea — are adjusting to the transition from the Cold War order in the Asia-Pacific to a new, as yet undefined regional order. As states occupying positions of privilege in the U.S.-led Cold War order, these two middle powers have engaged with the ASEAN grouping, the putative driver of the coming order, while maintaining traditional alliance commitments to the United States. This article focuses on proposals for the building of formal institutions and also other policies which can influence the formation of regional order, such as economic integration through the pursuit of free trade agreements. In examining an Asian and a non-Asian state, the article also considers how identity shapes attitudes to region and order.

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Aim: To examine prescription medication hoarding and borrowing or sharing (PMHBS) behaviours in older people, particularly which medications are subject to these behaviours and the circumstances that enable these behaviours.

Methods: A mixed methods triangulation design, using consecutive qualitative (focus groups) and quantitative (survey) methodologies in a convenience sample of people older than 65 years, living independently in the Illawarra region (New South Wales).

Results: Focus group participants (n= 28) acknowledged PMHBS behaviours were widespread; however, very few survey respondents (n= 226) admitted to engaging in these behaviours. Main findings in the study were enablers for these behaviours: the prescription medication is considered the same as that prescribed previously; and self-medicating for pain relief.

Conclusions:
The prevalence of PMHBS behaviours in this study was low, although it was acknowledged such behaviours occurred in the wider community. Sharing strong pain medication and the same prescription medication appeared to be acceptable in this population.