• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2931
  • 637
  • 74
  • 32
  • 32
  • 32
  • 32
  • 32
  • 32
  • 30
  • 29
  • 12
  • 10
  • 8
  • 8
  • Tagged with
  • 4668
  • 980
  • 657
  • 375
  • 358
  • 332
  • 321
  • 289
  • 276
  • 275
  • 256
  • 236
  • 230
  • 230
  • 229
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Histamine ??? a naturally occurring settlement cue for larvae of the Australian sea urchin Holopneustes purpurascens

Swanson, Rebecca, School of Biological, Earth & Environmental Sciences, UNSW January 2006 (has links)
The importance of chemical cues in triggering the settlement of marine invertebrate larvae has long been recognised but very few such cues have been definitively identified. Larvae of the Australian sea urchin Holopneustes purpurascens, which lives enmeshed in the fronds of macroalgae, are induced to settle by a water-soluble cue produced by the host alga Delisea pulchra. This cue was previously identified as a floridoside-isethionic acid complex. I present evidence in this thesis which supports histamine as the true settlement cue for larval H. purpurascens. The settlement cue was isolated from the polar extract of D. pulchra by bioassay-guided cation-exchange chromatography and identified as histamine using nuclear magnetic resonance spectroscopy. Algal derived and synthetic histamine at ~5 ??M induced rapid settlement in 80???100 % of larval H. purpurascens. In the first study of its kind for any marine invertebrate, variation in the distribution of new recruits was compared with quantitative variation in the distribution of histamine in the habitat. More than 90 % of new recruits were found on either the foliose red alga D. pulchra or on coralline turf algae. These algae induced &gt90 % settlement of larvae in laboratory assays after 24 h. D. pulchra contained far higher levels of histamine than all other algae, however, the coralline algae lacked measurable histamine. Seawater collected in situ adjacent to D. pulchra induced up to 16 % settlement of older larvae and contained the highest concentration of histamine (~5 nM). With the exception of coralline algae, variation in settlement and recruitment was consistent with the variation among species histamine contents. Initial results supported a biofilm derived settlement cue from coralline algae. I also showed that older H. purpurascens larvae settle in response to lower concentrations of histamine than younger larvae and required less exposure to histamine (10 ??M) in order to initiate irreversible metamorphosis. Histamine induced settlement of two other echinoids with non-feeding larvae. Histamine did not induce settlement of feeding larvae of two echinoids or settlement of non-feeding larvae of asteroids. Histamine may be a general settlement cue for echinoids with direct development.
322

The relationship between evidence and policy: a tracer study of promoting health equity through early childhood intervention in Australia

Bowen, Shelley, Public Health & Community Medicine, Faculty of Medicine, UNSW January 2007 (has links)
This thesis describes what counts as evidence and what constitutes an evidence-informed approach to health policy development, particularly policy with an equity focus. While health policy is increasingly aiming to be ???evidence-based???, a narrow conceptualisation of this can neglect the importance of the powerful and dynamic context of public policy-making. An evidence-informed approach recognises and works with a broader range of contextual influences. The aim of this thesis was to extend and deepen understanding of how evidence informs policy that promotes health equity, through a tracer study of policy development in Australia. The objectives of the research were to examine influential types of evidence, their role and function; to investigate the context, processes and relationships that contributed to evidence informed health policy, and to gain a deeper understanding of how health equity, and evidence on equity, was conceptualised and considered in the policy process. Two Australian state government policy initiatives in the area of early childhood intervention were investigated through interviews with key policy actors in both states, and media, political and policy documentary analyses. A theory-informed framework was developed from the literature to guide this research. This thesis has led to the development of a number of theoretical models, insights and working principles to guide evidence-informed policy development. The models emerge from a conceptual framework that describes how clusters of information (contextual, expert opinion, scientific studies, policy audit, and economic) combine with a number of policy conditions (necessity, opportunity, capacity, relationships, actors and processes) to become a ???case for policy???. What follows seems to be several primary insights to the types of evidence that inform health policy; the identification of an ???adopt, adapt, apply??? phase in policy-making; and the existence of an ???equity policy gap??? ??? exposing the rare translation of equity principles into policy action. Findings from this study call for recognition of research as only one information source in policy development. The successful integration of research and policy is more likely if research evidence is seen within, and as a part of, a more complex policy development system.
323

The payout phase of a defined contribution retirement income arrangement: the role of annuities.

Doyle, Suzanne, Economics, Australian School of Business, UNSW January 2008 (has links)
This thesis explores the economic issues associated with the payout phase where a defined contribution (DC) retirement arrangement is adopted. In particular, the role of annuities in providing a retirement income is examined as well as insurance they provide against retirement risks such as inflation, longevity and rate of return volatility. A comprehensive money’s worth calculation based on a Australian population cohort mortality table shows that overall, Australian nominal and inflation indexed life annuities provide relatively good value for money. Although relative to annuities sold in the US and the UK they do suffer from relatively high adverse selection costs, which could in turn reduce demand. In addition, the presence of a government provided safety net pension could also result in low demand for annuities. These two issues suggest that government intervention may be warranted to ensure retirees have access to affordable private insurance to protect their retirement benefit. This could take the form of mandating an annuity purchase at retirement. However, which annuity should be mandated is not well understood. This is an important question as there are many alternative annuity designs, each providing different degrees of retirement risk protection to an individual. This thesis uses numerical simulations to empirically analyse the costs and benefits of mandating alternative annuities from both an individual and government’s perspectives to determine optimal annuity design. A model is used to estimate the value of payouts over time from various types of annuities across a range of retirement benefits. A means tested safety net pension is assumed to exist. Two stochastic variables — inflation and the risky rate of return, are simultaneously used to show how the annuity payouts react to theses changes, highlighting the insurance features of various annuities. Consumer preferences for the various annuities are estimated based on tolerance to risk. The variable annuity dominates the utility rankings under two conditions: -- when the relative risk aversion is low and a safety net payment isn’t available, and when the relative risk aversion is high and a safety net payment is made. Otherwise the CPI indexed annuity has the highest ranking. Sensitivity analysis shows that the results presented here are robust to a number of alternative assumptions about the key variables.
324

Troubling spaces: The politics of ???New??? community-based guerrilla performance in Australia

Caines, Rebecca , English, Media, & Performing Arts, Faculty of Arts & Social Sciences, UNSW January 2008 (has links)
This thesis examines the politics of twenty-first century ???guerrilla??? performance. It historicises site-specific, political performance by examining ???guerrilla??? art forms from the 1960s to the present. It argues that recent community-based, site-specific performance events can be seen as a ???new??? type of guerrilla work, as they utilise techniques which challenge public space, authorship and control without resorting to traditional guerrilla forms of didactic street protest. The author establishes two main political tactics of the community-based guerrilla artist. The first is the utilisation of a problematised definition of ???community??? and the second is an understanding of physical, conceptual and experiential ???space??? as open to intervention. Community-based performance and site-specific art practices are investigated and space and community are placed into critical theoretical frameworks using post-structural and spatiality theory. The author then argues that post-structured communities which are based on an ethics of difference can trouble and create site, conceptual space and place (site/concept/place) through contemporary guerrilla performance events. Three examples of community-based guerrilla performance in Australia are examined. The first case study explores Western Sydney based Urban Theatre Projects and their 1997 performance event TrackWork. The second focuses on community-based hip-hop artist Morganics and his facilitation of two hip-hop tracks Down River and The Block in 2001. The third considers US theatre director Peter Sellars??? problematic curation of the 2002 Adelaide Festival of the Arts. In all three case studies, guerrilla artists are shown working with post-structured communities to challenge and trouble site/concept/place in order to improve the lives of their participants and audiences. This thesis proposes new post-structural frameworks for the powerful presence of community and site in performance events, thus contributing to performance and cultural studies and to the emerging field of community-based performance scholarship.
325

The glittering city: moving the moving image

Yamani, Jamil, Art, College of Fine Arts, UNSW January 2007 (has links)
The project aims to produce an immersive video installation titled 'The Glittering City???. This project investigates contemporary cultural issues within the context of critical/specific geographical sites. These locations are the Australian coastal border, and a refugee camp near the Kenyan/Sudanese border, known as Kakuma. 'The Glittering City'is an installation that incorporates elements of video, sculpture, sound and electronics in a kinetic 2 channel immersive video and (multi-channel) audio installation. The key aims for the project are to raise awareness of the issues facing refugees and asylum seekers in relation to their sense of home. In order to accomplish this aim the research will extend upon prior research into embedded video sculptures. A subset of the key aim is to seek funding for the project. The installation is the third and final work from a trilogy of works that explores the themes journey, arrival and departure, respectively. The Glittering City is contextualised within four key areas inherent within the research practice. These key elements are 1. hybrid documentary art, 2. expanded cinema, 3. Technology and art, 4. culture and identity. Key outcomes of the research are the production and installation of The Glittering City at Campbelltown Arts Centre, May 2007. An educational program also took place at the Centre to raise awareness of the themes the installation poses. The production of a catalogue for The Glittering City is an important device for disseminating the core concepts. For the costs of making the multi-channel production, the project successfully sought grant funding from Arts NSW. This resulted in a grant through their Western Sydney I Artists' Fellowship program. The Glittering City used further funding from the Campbelltown Arts Centre to cover catalogue production, invitation design, mail out and installation costs.
326

Molecular Relatedness, Paternity and Male Alliances in Bottlenose Dolphins (Tursiops sp.) in Shark Bay, Western Australia

Kr??tzen, Michael Christian, School of Biological, Earth & Environmental Sciences, UNSW January 2002 (has links)
Male bottlenose dolphins (Tursiops sp.) in Shark Bay, WA, form several levels of alliances. Determining the relationship between paternity, relatedness and alliance membership is crucial in seeking evolutionary adaptive explanations for alliance formation. Previous behavioural data have revealed a social system whose complexity is unparalleled outside humans. Pairs or trios of male dolphins cooperate as stable first-order (1? alliances to sequester and control reproductive females. Two 1?alliances sometimes cooperate as small second-order (2? alliances to attack other 1?alliances or defend against attacks. Some males choose a different strategy by forming large superalliances of approximately fourteen individuals to attack 1?and 2?alliances. Kinship appears to play a role in the structuring of male alliances, but its importance differs with the alliance type. Relatedness analyses showed that on average, males in 1?and 2?alliances are strongly related, while members of the superalliance are not. Further, the strength of the association of partners within the superalliance was not correlated with their genetic relatedness. Thus, within one sex, it appears that there may be more than one simultaneous mode of group formation and its evolution. There was also an association between alliance behaviour and reproductive success as predicted by some theories of group formation. I assigned nine paternities to six out of 107 mature males. Males with alliance partners were significantly more successful in fathering offspring than males without partners. Compared to non-allied males, the chance of obtaining a paternity was significantly higher for members of 1?alliances, and reproductive success was significantly skewed among 1?alliance members. Assessment of kinship and relatedness required a number of technical developments and some preliminary data. I first refined a biopsy system in order to obtain tissue samples from free-ranging dolphins with minimum behavioural effects irrespective of age-group or gender. Then I carried out population genetics analyses, which demonstrated that there was only weak population structure within Shark Bay. Microsatellites showed a weak pattern of isolation by distance, and eight haplotypes of the mitochondrial DNA control region suggested weak female philopatry. The high number of migrants between locations allowed all samples from East Shark Bay to be pooled for subsequent analyses.
327

Phylogeography, population history and conservation genetics of the endangered green and golden bell frog (Litoria aurea)

Burns, Emma Louise, School of Biological, Earth & Environmental Sciences, UNSW January 2004 (has links)
The green and golden bell frog (Litoria aurea) is an Australian hylid, which was once common with a relatively continuous distribution. Historically, this distribution extended from northern New South Wales (NSW), as far as Ballina, to East Gippsland in Victoria; with inland populations as far west as Bathurst and Tumut. Today the species is reported to have disappeared from 80% of its former range and remaining populations are mostly fragmented and typically restricted to the coastline, extending from Yuraygir National Park (northern NSW) to East Gippsland. In this thesis, I report a comprehensive study designed to identify the phylogeographic and conservation genetic parameters of L. aurea. In doing so, I also investigate evolutionary relationships within the ???bell frog??? species group. In this study, microsatellite and mitochondrial DNA (mtDNA) markers are employed. The development of species-specific microsatellite markers and the collection of samples was a substantial component of the study. These markers and samples should prove useful for future studies of L. aurea and perhaps more generally the ???bell frogs???. Initially, a large-scale assessment of genetic structure and diversity in L. aurea using microsatellite markers was undertaken. Twenty-one locations were sampled from throughout the species range covering 1000 kilometres of the east coast of Australia. Levels of allelic diversity and heterozygosity were high (uncorrected mean alleles/locus and HE: 4.8-8.8 and 0.43-0.8 respectively) compared to other amphibian species and significant differences among sampled sites were recorded. Despite recent population declines, no sites displayed a genetic signature indicative of a population bottleneck. Significant genetic structuring (overall FST = 0.172) was detected throughout the species range, but was relatively low compared to previous amphibian studies that used microsatellites. In addition, some areas sampled within continuous habitat showed evidence of weak genetic structuring (data subset FST = 0.034). Next, relationships among extant bell frogs (Litoria aurea species-group) were investigated, using mitochondrial ND4 nucleotide sequence data. Analyses supported a clade comprised of the temperate members of the species-group, L. aurea, L. cyclorhyncha, L. moorei, and L. raniformis but failed to support the inclusion of the tropical bell frog L. dahlii in this group. Relationships among the four members of the bell frog clade correlated with geographical distribution: the south-western Australian bell frogs (L. cyclorhyncha, L. moorei) and the south-eastern Australian bell frogs (L. aurea, L. raniformis) were reciprocally monophyletic. Results also indicated that divergence of these two lineages occurred during the late Miocene, which was consistent with results of previous studies and with more general assertions that much of the major differentiation and radiation of the Australian biota predated the Quaternary. Following this, intraspecific phylogeography of L. aurea using two mitochondrial genes COI and ND4 was investigated. I examined extant populations from throughout the species??? range, sequencing 263 individuals from twenty-six locations. Recent evolutionary history, as well as the current population structure of L. aurea, was inferred from the resulting pattern of genetic variation amongst haplotypes, in conjunction with demographic and population analyses. Results indicated that there were no phylogeographic divisions within L. aurea, despite a general consensus that amphibians are highly structured. However, I did still detect significant structure amongst extant populations (FST = 0.385). Overall, patterns of haplotype relatedness, high haplotypic diversity (mean h = 0.547) relative to low nucleotide diversity (mean Pi= 0.003), and mismatch distribution analysis supported a Pleistocene expansion hypothesis with continued restricted dispersal and gene flow. Taken together, the results of this thesis indicate that L. aurea is a species with relatively weak population and phylogeographic structure compared to other amphibians. The data provide no support for the existence of distinct evolutionary lineages within L. aurea, implying that there are no historically isolated populations that should be viewed as separate evolutionarily significant units. Nevertheless, remaining populations are still significantly structured but not all populations are genetically distinct. Low phylogeographic structure, coupled with evidence for recent gene flow among many sites would permit ???well managed??? intervention to mediate gene flow amongst currently isolated populations, and I provide some guidelines for the implementation of such conservation strategies. However, there is no evidence to suggest that supplementation through artificial immigration is at this time necessary given current levels of genetic variation within populations. In the short-term, conservation management in L. aurea should focus on the protection of local populations and habitat to promote population connectivity to ensure processes that maintain adaptive diversity and evolutionary potential are conserved. Preservation of the species??? natural range and the maintenance of dense networks of suitable habitat, in conjunction with maximising local carrying capacity and reproductive output, as well as minimising known threats, are key to securing the long-term persistence of the green and golden bell frog.
328

The balance of power in Second World War Australia :the deliberative role of Coles and Wilson in the House of Representatives from 1940

Hayman, Christopher Charles Douglas, School of Politics & International Relations, UNSW January 2005 (has links)
The problem being investigated is the historical situation relating to two independent MPs holding the balance of power in the Australian House of Representatives in 1940 and 1941. The two MPs, Arthur Coles and Alex Wilson, supported the conservative Menzies and Fadden governments before shifting their support (on October 3 1941) to the Labor Party led by Curtin. The procedure followed is the examination, in the form of a historical narrative, of primary evidence in private papers (such as Coles???s), analysis of Hansard (CPD), local and metropolitan newspapers. Also examined are references to the two independents in secondary literature. The key focus of interest will be the idea that chance or serendipity played a major role in achieving all the key outcomes which many Australians (and historians like Hasluck) often otherwise depict as the triumph of good sense within a supposedly non-problematic twoparty political system which self-selected the best possible leadership during time of war. Coles took over the seat of a popular Cabinet minister who had died in an air disaster. Coles???s and Wilson???s holding the balance of power was another extreme aberration, as no House of Representatives from 1906 to 1940, and none since, has not had either of the two party blocs (Labor and anti-Labor) without a majority. Hasluck, the most influential historian of Australian politics during the 1939-1945 war, viewed the fact of Coles???s and Wilson???s serendipity as evidence, in itself, of their wider historical, ideological and political irrelevance. The general results obtained by pursuing a critical historical narrative approach is that a strong counter-argument has been developed that suggests that Hasluck (and wider historical memory) has insufficiently valued as historical factors Coles???s and Wilson???s ideological aims. Coles was a representative of business progressivism and Wilson of agrarian socialism. The major conclusion reached is that Coles???s and Wilson???s wider aims led them to adopt the tactic of timing their shift to Labor so as to maximize their ideological influence on the Labor administration that would result whenever they decided to exercise their entirely serendipitously attained balance of power.
329

Overlapping in Japanese conversation: communication styles of Japanese long-term residents of Australia in terms of Japanese socio-cultural/gender norms

Iida, Sumiko, Modern Language Studies, UNSW January 2005 (has links)
This study analyses overlaps in naturally occurring multi-party conversations among Japanese long-term residents of Australia, to investigate how Australian culture influences their Japanese communication style. One of the study???s interests is how their gendered communication styles appear in Australian English culture. Japanese gendered communication styles have been discussed in the literature, for example that males interrupt females more than vice versa; active participation by males versus passive participation by females in mixed-gender conversations; self-oriented topic initiation by males versus other-oriented topic initiation by females etc. These styles were assumed to be rarely observed in their L1 communication styles in Australia, where English, in which gendered language is less distinctive than Japanese, is spoken, and gender-free society has been more emphasised and practiced than in Japan. Among conversations recorded by the two informants, three multi-party conversations per informant (i.e. six in total) were selected, in which over 2000 overlaps are observed. The study first established a framework of functional overlap classification in terms of the ownership of the conversational floor. Then, based on this frame, all overlaps were classified into a number of functional categories, and were analysed qualitatively as well as quantitatively. The results showed little differences in the Japanese communication styles of the long-term residents of Australia from the Japanese communication styles which have been discussed in the literature, such as frequent use of aizuchi and other cooperative overlaps at and other than at Transition Relevance Places. As for gendered communication style, at least socio-cultural norms between traditional Japanese husband and wife are observed in the informants??? communication style. Although a number of variables that surround the informants need to be considered, the results may suggest that Japanese socio-cultural norms are, at this stage, more stable and they maintain the communication style of the Japanese long-term residents of foreign culture in their first language communication more strongly than was expected. However, different trends may be observed in future.
330

Taxonomy and ecology of predatory marine flatworms (Platyhelminthes: Polycladida) in Botany Bay, New South Wales, Australia

Lee, Ka-Man, School of Biological, Earth & Environmental Sciences, UNSW January 2006 (has links)
Marine flatworms are important mobile predators on hard substrate, however little is known about their life history. I recorded seven species of flatworms in Botany Bay and described a new species of flatworm Imogine lateotentare sp. nov. It is distinguished from other species in the same genus by having small, transparent and inconspicuous tentacles and continuous bands of numerous frontal and cerebral eyes. This new flatworm species was found closely associated with the barnacle Balanus variegatus (Darwin, 1854) on which it fed. Marine flatworms provide elaborate parental care to their offspring but its significance has not been experimentally confirmed. I provided quantitative measurements of the significance of parental care behaviour in Echinoplana celerrima and Stylochus pygmaeus under controlled laboratory conditions. I also examined the changes in reproductive behaviour of E. celerrima and the hatching success of their eggs when exposed to three putative flatworm egg predators. Brooding behaviour of neither species of flatworm enhanced the hatching success of their eggs and exposure of E. celerrima to the potential egg predators did not affect the timing of hatching or hatching success of its eggs. However, E. celerrima spent more time guarding their eggs when exposed to the potential egg predators. Brooding may be an innate behaviour in marine flatworms but it is not essential to their reproductive success. Marine flatworms are closely associated with sessile organisms and these assemblages are common in bays and estuaries which are subject to anthropogenic inputs from various sources. Impacts of pollutants are known for many flatworm prey species but little is known about the effects on the flatworm themselves. I examined the influence of sublethal concentrations of copper ranging from 0 to 50 ??g L-1 on the predatory and reproductive behaviour of Stylochus pygmaeus. These worms were more sensitive to low levels of copper pollution than their barnacle preys. Response of flatworms to physical stimulation, number of egg batches laid and hatching success were greatly reduced at higher copper concentrations. In areas polluted by heavy metals, flatworm populations will be affected at lower concentrations than their barnacle prey and which may alter sessile invertebrate community structure.

Page generated in 0.063 seconds