852 resultados para Ross, John


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During 1996-1998 60,619 mosquitoes were collected around Cairns, Australia and processed for Alphavirus isolation. Thirty-three isolates of Ross River (RR) virus were made from 9 species, Aedes imprimens, Aedes kochi, Aedes notoscriptus, Aedes vigilax, Culex annulirostris, Culex gelidus, Mansonia septempunctata, Verrallina (formerly Aedes) carmenti, and Verrallina lineatus. Attempts to isolate RR virus from 121 Aedes aegypti were unsuccessful. Twenty six (79%) of the isolates came from within 1 km of a colony of spectacled flying-foxes, Pteropus conspicillatus. The minimum infection rate for these mosquitoes was 1.0 compared with 0.2 per 1,000 for mosquitoes trapped at all other sites. Ross River virus has not previously been isolated from Ae. imprimens, Cx. gelidus, Ma. septempunctata, Ve. carmenti, or Ve. lineatus. This is also the first isolation of an arbovirus from Cx. gelidus in Australia. In conclusion, the vector status of Ve. carmenti, Ae. aegypti and Mn. septempunctata warrants further study. This study also provides evidence that P. conspicillatus may be a reservoir host.

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The flavivirus Japanese encephalitis (JE) virus has recently emerged in the Australasian region. To investigate the involvement of infections with related enzootic flaviviruses, namely Murray Valley encephalitis (MVE) virus and Kunjin (KUN) virus, on immunity of pigs to JE virus and to provide a basis for interpretation of serologic data, experimental infections were conducted with combinations of these viruses. Antibody responses to primary and secondary infections were evaluated using panels of monoclonal antibody-based blocking enzyme-link-ed immuno-sorbent assays and microtiter scrum neutralization tests (mSNTs). Identification of the primary infecting virus was possible only using the mSNTs. Following challenge, unequivocal diagnosis was impossible due to variation in immune responses between animals and broadened and/or anamnestic responses. Viremia for JE virus was readily detected in pigs following primary infection, but was not detected following prior exposure to MVE or KUN viruses. Boosted levels of existing cross-neutralizing antibodies to JE virus suggested a role for this response in suppressing JE viremia.

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Stable isotope analyses of marine bivalve growth increment samples have been used to estimate early Oligocene (29.4 - 31.2) Ma and early Miocene (24.0 Ma) seafloor palaeotemperatures from the southwestern continental margin of the Ross Sea. Measured δ18O values average +2.5‰ in the early Miocene and range between +1.26 to +3.24‰ in the early Oligocene. The results show that palaeoceanographic conditions in McMurdo Sound during the mid-Cenozoic were significantly different from those of today. The minimum estimated spring through late summer seasonal temperature range was 3°C during the early Miocene and between 1 and 5°C during the early Oligocene. This compares to the equivalent modern day range of

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Hailed as an 'unruly masterpiece', John Romeril's The Floating World is one of the few 'new wave' Australian plays representing Australians and their Asian 'others' to be restaged periodically since its premiere in 1974. Paying particular attention to production of the play that have used Japanese theatre forms such as kabuki and bunraku, this article focuses primarily on the ways in which the significations of race have been interpreted by the critical establishment. The fascinating stage history of The Floating World is treated as a barometer of Australian theatre's response to the challenge of representing cultural conflict, during a period marked by public debate about the desirability, and inevitability, of Australia's political, economic and cultural 'enmeshment' with Asia.

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Brushtail possums, Trichosurus vulpecula Kerr, were experimentally infected with Ross River (RR) or Barmah Forest (BF) virus by Aedes vigilax (Skuse) mosquitoes. Eight of 10 animals exposed to RR virus developed neutralizing antibody, and 3 possums developed high viremia for < 48 hr after infection, sufficient to infect recipient mosquitoes. Two of 10 animals exposed to BF virus developed neutralizing antibody. Both infected possums maintained detectable neutralizing antibody to BF for at least 45 days after infection (log neutralization index > 2.0 at 45 days). Eight possums did not develop neutralizing antibody to BF despite exposure to infected mosquitoes. These results suggest that T. vulpecula may potentially act as a reservoir species for RR in urban areas. However, T. vulpecula infected with BF do not develop viremia sufficient to infect mosquitoes and are unlikely to be important hosts for BF.