63 resultados para Australia. Dept. of Defence


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A detailed pollen record from the Ocean Drilling Program Site 820 core, located on the upper part of the continental slope off the coast of northeast Queensland, was constructed to compare with the existing pollen record from Lynch's Crater on the adjacent Atherton Tableland and allow the production of a regional picture of vegetation and environmental change through the last glacial cycle. Some broad similarities in patterns of vegetation change are revealed, despite the differences between sites and their pollen catchments, which can be related largely to global climate and sea-level changes. The original estimated time scale of the Lynch's Crater record is largely confirmed from comparison with the more thoroughly dated ODP record. Conversely, the Lynch's Crater pollen record has assisted in dating problematic parts of the ODP record. In contrast to Lynch's Crater, which reveals a sharp and sustained reduction in drier araucarian forest around 38,000 yrs BP, considered to have been the result of burning by Aboriginal people, the ODP record indicates, most likely, a stepwise reduction, dating from 140,000 yrs BP or beyond. The earliest reduction shows lack of a clear connection between Araucaria decline and increased burning and suggests that people may not have been involved at this stage. However, a further decline in araucarian forest, possibly around 45,000 yrs BP, which has a more substantial environmental impact and is not related to a time of major climate change, is likely, at least partially, the result of human burning. The suggestion, from the ODP core oxygen isotope record, of a regional sea-surface temperature increase of around 4 degrees C between about 400,000 and 250,000 yrs BP, may have had some influence on the overall decline in Araucaria and its replacement by sclerophyll vegetation. (C) 2000 Elsevier Science B.V. All rights reserved.

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Objective: This study reports the prevalence and correlates of ICD-10 alcohol- and drug-use disorders in the National Survey of Mental Health and Wellbeing (NSMHWB) and discusses their implications for treatment. Method: The NSMHWB was a nationally representative household survey of 10 641 Australian adults that assessed participants for symptoms of the most prevalent ICD-10 and DSM-IV mental disorders, including alcohol- and drug-use disorders. Results: In the past 12 months 6.5% of Australian adults met criteria for an ICD-10 alcohol-use disorder and 2.2% had another ICD-10 drug-use disorder. Men were at higher risk than women of developing alcohol- and drug-use disorders and the prevalence of both disorders decreased with increasing age. There were high rates of comorbidity between alcohol- and other drug-use disorders and mental disorders and low rates of treatment seeking. Conclusions: Alcohol-use disorders are a major mental health and public health issue in Australia. Drug-use disorders are less common than alcohol-use disorders, but still affect a substantial minority of Australian adults. Treatment seeking among persons with alcohol- and other drug-use disorders is low. A range of public health strategies (including improved specialist treatment services) are needed to reduce the prevalence of these disorders.

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Australia’s transition to the 21st century has been marked by an extended period of economic prosperity unmatched for several decades, but one in which a series of question marks are being raised in three principal areas: in relation to the environment, the social well-being of the population, and the future path of economic development. The first concern, which is of primary interest in this report, relates to the physical environment of cities and their surrounding regions, and the range of pressures exerted by population and human activity. The report begins by noting the increasing divergence of the prime indicator of national economic performance—gross domestic product (GDP)—from the Genuine Progress Indicator (GPI). GPI is a new experimental measure of sustainable development that accommodates factors currently unaccounted for in GDP, such as income distribution, value of household work, cost of unemployment, and various other social and environmental costs. The divergence of these two indicators in recent decades suggests that Australia’s growth has been heavily dependent on the draw-down of the nation’s stocks of capital assets (its infrastructure), its human and social capital, and its natural capital (Hamilton 1997).

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The virulence spectrum of 112 isolates of Phytophthora clandestina collected from 56 sites in four subterranean clover-growing states in southern Australia was determined using differential cultivars of subterranean clover. Five races were detected, with race 0 in all states except New South Wales, race 1 in all states, race 2 only in Victoria, race 3 only in New South Wales, and race 4 in Victoria and Western Australia. The level of genotypic diversity among the different P. clandestina populations was investigated using five RAPD primers. Among 30 bands amplified, only two were polymorphic. This enabled identification of four multilocus RAPD genotypes. Three of the four genotypes occurred in all four states. Races 2 and 3 occurred with RAPD genotypes 1 and 2 only whereas races 0 and 1 occurred in all four multilocus RAPD genotypes. These results indicate that the pathogenicity spectrum of P. clandestina can change rapidly.

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Murray Valley encephalitis (MVE) virus is a mosquito-borne flavivirus causing severe encephalitis with a resultant high morbidity and mortality. In the period 1989-1993. we undertook a cross-sectional and longitudinal studs by annually screening members of a small remote Aboriginal community in northwestern Australia for MVE virus antibodies. Of the estimated 250-300 people in the community. 249 were tested, and 52.6% had positive serology to MVE. The proportion testing positive increased with increasing age group. and males were slightly more likely to be positive than females. During the study period. a high proportion of the population seroconverted to MVE: the clinical/subclinical ratio seems to be lower than previously reported. Although MVE is mostly asymptomatic, the devastating consequences of clinical illness indicate that advice should be provided regarding the avoidance of mosquito bites. Our longitudinal study showed that the risk of seroconversion was similar for each age group. not just the young.

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As a component of archaeological investigations on the central Queensland coast, a series of five marine shell specimens live-collected between A.D. 1904 and A.D. 1929 and 11 shell/ charcoal paired samples from archaeological contexts were radiocarbon dated to determine local DeltaR values. The object of the study was to assess the potential influence of localized variation in marine reservoir effect in accurately determining the age of marine and estuarine shell from archaeological deposits in the area. Results indicate that the routinely applied DeltaR value of -5 +/- 35 for northeast Australia is erroneously calculated. The determined values suggest a minor revision to Reimer and Reimer's (2000) recommended value for northeast Australia from DeltaR = +11 +/- 5 to + 12 +/- 7, and specifically for central Queensland to DeltaR = +10 +/- 7, for near-shore open marine environments. In contrast, data obtained from estuarine shell/charcoal pairs demonstrate a general lack of consistency, suggesting estuary-specific patterns of variation in terrestrial carbon input and exchange with the open ocean. Preliminary data indicate that in some estuaries, at some time periods, a DeltaR value of more than - 155 +/- 55 may be appropriate, In estuarine contexts in central Queensland, a localized estuary-specific correction factor is recommended to account for geographical and temporal variation in C-14 activity. (C) 2002 Wiley Periodicals.

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We undertook annual surveys of flavivirus virus activity in the community of Billiluna of Western Australia in the southeast Kimberley region between 1989 and 2001. Culex annulirostris was the dominant mosquito species, particularly in years of above average rains and flooding. Murray Valley encephalitis (MVE) virus was isolated in 8 of the 13 years of the study from seven mosquito species, but more than 90% of the isolates were from Cx. annulirostris. The results suggest that MVE virus is epizootic in the region, with activity only apparent in years with average or above average rainfall and increased numbers of Cx. annulirostris. High levels of MVE virus activity and associated human cases were detected only once (in 1993) during the survey period. Activity of MVE virus could only be partially correlated with wet season rainfall and flooding, suggesting that a number of other factors must also be considered to accurately predict MVE virus activity at such communities.

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Almost half of the 4822 described beeflies in the world belong to the subfamily Anthracinae, with most of the diversity found in three cosmopolitan tribes: Villini, Anthracini, and Exoprosopini. The Australian Exoprosopini previously contained three genera, Ligyra Newman, Pseudopenthes Roberts and Exoprosopa Macquart. Pseudopenthes is an Australian endemic, with two species including Ps. hesperis, sp. nov. from Western Australia. Two new species of the exoprosopine Atrichochira Hesse, Atr. commoni, sp. nov. and Atr. paramonovi, sp. nov., are also described from Australia, extending the generic distribution from Africa. Cladistic analysis clarified the phylogenetic relationships between the recognised groups of the Exoprosopini and determined generic limits on a world scale. Inclusion of 18 Australian exoprosopines placed the Australian species in the context of the world fauna. The Exoprosopini contains six large groups. The basal group I contains species previously included in Exoprosopa to which the name Defilippia Lioy is applied. Group II contains Heteralonia Rondani, Atrichochira, Micomitra Bowden, Pseudopenthes, and Diatropomma Bowden. Colossoptera Hull is newly synonymised with Heteralonia. Group III is a paraphyletic assemblage of Pterobates Bezzi and Exoprosopa including the Australian Ex. sylvana ( Fabricius). Ligyra is paraphyletic, forming two well-separated clades. The African clade is described as Euligyra Lambkin, gen. nov., which, together with Litorhina Bezzi and Hyperalonia Rondani, form group IV. The Australian group V is true Ligyra. The remaining monophyletic lineage of exoprosopines, group VI, the Balaana-group of genera, shows evidence of an evolutionary radiation of beeflies in semi-arid Australia. Phylogenetic analysis of all 42 species of the Balaana-group of genera formed a basis for delimiting genera. Seven new genera are described by Lambkin & Yeates: Balaana, Kapua, Larrpana, Munjua, Muwarna, Palirika and Wurda. Four non-Australian species belong to Balaana. Thirty two new Australian species are described: Bal. abscondita, Bal. bicuspis, Bal. centrosa, Bal. gigantea, Bal. kingcascadensis, K. corusca, K. irwini, K. westralica, Lar. collessi, Lar. zwicki, Mun. erugata, Mun. lepidokingi, Mun. paralutea, Mun. trigona, Muw. vitreilinearis, Pa. anaxios, Pa. basilikos, Pa. blackdownensis, Pa. bouchardi, Pa. cyanea, Pa. danielsi, Pa. decora, Pa. viridula, Pa. whyalla, W. emu, W. impatientis, W. montebelloensis, W. norrisi, W. patrellia, W. skevingtoni, W. windorah, and W. wyperfeldensis. The following new combinations are proposed: from Colossoptera: Heteralonia latipennis (Brunetti); from Exoprosopa: Bal. grandis (Pallas), Bal. efflatounbeyi (Paramonov), Bal. latelimbata ( Bigot), Bal. obliquebifasciata ( Macquart), Bal. tamerlan (Portschinsky), Bal. onusta ( Walker), Def. busiris (Jaennicke), Def. efflatouni ( Bezzi), Def. eritreae (Greathead), Def. gentilis ( Bezzi), Def. luteicosta ( Bezzi), Def. minos (Meigen), Def. nigrifimbriata ( Hesse), Def. rubescens ( Bezzi), K. adelaidica ( Macquart), Lar. dimidiatipennis ( Bowden), Muw. stellifera ( Walker), and Pa. marginicollis ( Gray); from Ligyra: Eu. enderleini ( Paramonov), Eu. mars ( Bezzi), Eu. monacha (Klug), Eu. paris ( Bezzi), Eu. sisyphus ( Fabricius), and Eu. venus (Karsch).

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Rare earth element and yttrium (REE+Y) concentrations were determined in 49 Late Devonian reefal carbonates from the Lennard Shelf, Canning Basin, Western Australia. Shale-normalized (SN) REE+Y patterns of the Late Devonian samples display features consistent with the geochemistry of well-oxygenated, shallow seawater. A variety of different ancient limestone components, including microbialites, some skeletal carbonates (stromatoporoids), and cements, record seawater-like REE+Y signatures. Contamination associated with phosphate, Fe-oxides and shale was tested quantitatively, and can be discounted as the source of the REE+Y patterns. Co-occurring carbonate components that presumably precipitated from the same seawater have different relative REE concentrations, but consistent REE+Y patterns. Clean Devonian early marine cements (n = 3) display REE+Y signatures most like that of modern open ocean seawater and the highest Y/Ho ratios (e.g., 59) and greatest light REE (LREE) depletion (average Nd-SN/Yb-SN = 0.413, SD = 0.076). However, synsedimentary cements have the lowest REE concentrations (e.g., 405 ppb). Non-contaminated Devonian microbialite samples containing a mixture of the calcimicrobe Renalcis and micritic thrombolite aggregates in early marine cement (n = 11) have the highest relative REE concentrations of tested carbonates (average total REE = 11.3 ppm). Stromatoporoid skeletons, unlike modern corals, algae and molluscs, also contain well-developed, seawater-like REE patterns. Samples from an estuarine fringing reef have very different REE+Y patterns with LREE enrichment (Nd-SN/Yb-SN > 1), possibly reflecting inclusion of estuarine colloidal material that contained preferentially scavenged LREE from a nearby riverine input source. Hence, Devonian limestones provide a proxy for marine REE geochemistry and allow the differentiation of co-occurring water masses on the ancient Lennard Shelf. Although appropriate partition coefficients for quantification of Devonian seawater REE concentrations from out data are unknown, hypothetical Devonian Canning Basin seawater REE patterns were obtained with coefficients derived from modern natural proxies and experimental values. Resulting Devonian seawater patterns are slightly enriched in LREE compared to most modem seawaters and suggest higher overall REE concentrations, but are very similar to seawaters from regions with high terrigenous inputs. Our results suggest that most limestones should record important aspects of the REE geochemistry of the waters in which they precipitated, provided they are relatively free of terrigenous contamination and major diagenetic alteration from fluids with high, non-seawater-like REE contents. Hence, we expect that many other ancient limestones will serve as seawater REE proxies, and thereby provide information on paleoceanography, paleogeography and geochemical evolution of the oceans. Copyright (C) 2004 Elsevier Ltd.