Literatura académica sobre el tema "Marsupial viruses in Australia"
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Artículos de revistas sobre el tema "Marsupial viruses in Australia"
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Hernández, Leonardo H. Almeida, Thito Y. Bezerra da Paz, Sandro Patroca da Silva, Fábio S. da Silva, Bruno C. Veloso de Barros, Bruno T. Diniz Nunes, Lívia M. Neves Casseb, Daniele B. Almeida Medeiros, Pedro F. da Costa Vasconcelos y Ana C. Ribeiro Cruz. "First Genomic Evidence of a Henipa-like Virus in Brazil". Viruses 14, n.º 10 (30 de septiembre de 2022): 2167. http://dx.doi.org/10.3390/v14102167.
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The viral genus Henipavirus includes two highly virulent zoonotic viruses of serious public health concern. Hendra henipavirus and Nipah henipavirus outbreaks are restricted to Australia and Southeast Asia, respectively. The Henipavirus genus comprises mostly bat-borne viruses, but exceptions have already been described as novel viruses with rodents and shrews as reservoir animals. In the Americas, scarce evidence supports the circulation of these viruses. In this communication, we report a novel henipa-like virus from opossums (Marmosa demerarae) from a forest fragment area in the Peixe-Boi municipality, Brazil, after which the virus was named the Peixe-Boi virus (PBV). The application of next-generation sequencing and metagenomic approach led us to discover the original evidence of a henipa-like virus genome in Brazil and South America and the original description of a henipa-like virus in marsupial species. These findings emphasize the importance of further studies to characterize PBV and clarify its ecology, impact on public health, and its relationship with didelphid marsupials and henipaviruses.
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Antonsson, Annika y Nigel A. J. McMillan. "Papillomavirus in healthy skin of Australian animals". Journal of General Virology 87, n.º 11 (1 de noviembre de 2006): 3195–200. http://dx.doi.org/10.1099/vir.0.82195-0.
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Papillomaviruses are a group of ubiquitous viruses that are often found in normal skin of humans, as well as a range of different vertebrates. In this study, swab samples collected from the healthy skin of 225 Australian animals from 54 species were analysed for the presence of papillomavirus DNA with the general skin papillomavirus primer pair FAP59/FAP64. A total of five putative and potential new animal papillomavirus types were identified from three different animal species. The papillomaviruses were detected in one monotreme and two marsupial species: three from koalas, and one each from an Eastern grey kangaroo and an echidna. The papillomavirus prevalence in the three species was 14 % (10/72) in koalas, 20 % (1/5) in echidnas and 4 % (1/23) in Eastern grey kangaroos. Phylogenetic analysis was performed on the putative koala papillomavirus type that could be cloned and it appears in the phylogenetic tree as a novel putative papillomavirus genus. The data extend the range of species infected by papillomaviruses to the most primitive mammals: the monotremes and the marsupials.
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J. Foley, William. "Marsupial Nutrition". Pacific Conservation Biology 5, n.º 3 (1999): 240. http://dx.doi.org/10.1071/pc99240a.
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In the early 1980s advances in marsupial biology could no longer be encapsulated in a single volume such as Hugh Tyndale-Biscoe's "Life of Marsupials" and Cambridge University Press commissioned a series of monographs covering a range of different topics in marsupial biology. As it was, only three of that series were realized and among them was the ptedecessor to this book "Digestive Physiology and Nutrition of Marsupials" published in 1982. "Marsupial Nutrition" is a considerably expanded and comprehensive review of studies of nutrition and digestive physiology of Australasian and South American marsupials. In Australia, many ecologists view the limited nutrient status of our soils and vegetation as a fundamental limit to animal populations. This book explains firstly how Australian marsupials have responded to those limitations and secondly asks whether these responses are common amongst marsupials living in New Guinea and South America.
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Rothschild, Bruce M. y Ralph E. Molnar. "Osteoarthritis in fossil marsupial populations of Australia". Annals of the Carnegie Museum 57 (15 de septiembre de 1988): 155–58. http://dx.doi.org/10.5962/p.226657.
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Price, Gilbert J., Kyle J. Ferguson, Gregory E. Webb, Yue-xing Feng, Pennilyn Higgins, Ai Duc Nguyen, Jian-xin Zhao, Renaud Joannes-Boyau y Julien Louys. "Seasonal migration of marsupial megafauna in Pleistocene Sahul (Australia–New Guinea)". Proceedings of the Royal Society B: Biological Sciences 284, n.º 1863 (27 de septiembre de 2017): 20170785. http://dx.doi.org/10.1098/rspb.2017.0785.
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Seasonal two-way migration is an ecological phenomenon observed in a wide range of large-bodied placental mammals, but is conspicuously absent in all modern marsupials. Most extant marsupials are typically smaller in body size in comparison to their migratory placental cousins, possibly limiting their potential to undertake long-distance seasonal migrations. But what about earlier, now-extinct giant marsupial megafauna? Here we present new geochemical analyses which show that the largest of the extinct marsupial herbivores, the enormous wombat-like Diprotodon optatum , undertook seasonal, two-way latitudinal migration in eastern Sahul (Pleistocene Australia–New Guinea). Our data infer that this giant marsupial had the potential to perform round-trip journeys of as much as 200 km annually, which is reminiscent of modern East African mammal migrations. These findings provide, to our knowledge, the first evidence for repetitive seasonal migration in any metatherian (including marsupials), living or extinct, and point to an ecological phenomenon absent from the continent since the Late Pleistocene.
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Archer, Michael, Robin Beck, Miranda Gott, Suzanne Hand, Henk Godthelp y Karen Black. "Australia's first fossil marsupial mole (Notoryctemorphia) resolves controversies about their evolution and palaeoenvironmental origins". Proceedings of the Royal Society B: Biological Sciences 278, n.º 1711 (3 de noviembre de 2010): 1498–506. http://dx.doi.org/10.1098/rspb.2010.1943.
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Fossils of a marsupial mole (Marsupialia, Notoryctemorphia, Notoryctidae) are described from early Miocene deposits in the Riversleigh World Heritage Area, northwestern Queensland, Australia. These represent the first unequivocal fossil record of the order Notoryctemorphia, the two living species of which are among the world's most specialized and bizarre mammals, but which are also convergent on certain fossorial placental mammals (most notably chrysochlorid golden moles). The fossil remains are genuinely ‘transitional', documenting an intermediate stage in the acquisition of a number of specializations and showing that one of these—the dental morphology known as zalambdodonty—was acquired via a different evolutionary pathway than in placentals. They, thus, document a clear case of evolutionary convergence (rather than parallelism) between only distantly related and geographically isolated mammalian lineages—marsupial moles on the island continent of Australia and placental moles on most other, at least intermittently connected continents. In contrast to earlier presumptions about a relationship between the highly specialized body form of the blind, earless, burrowing marsupial moles and desert habitats, it is now clear that archaic burrowing marsupial moles were adapted to and probably originated in wet forest palaeoenvironments, preadapting them to movement through drier soils in the xeric environments of Australia that developed during the Neogene.
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Arena, Derrick A., Michael Archer, Henk Godthelp, Suzanne J. Hand y Scott Hocknull. "Hammer-toothed ‘marsupial skinks' from the Australian Cenozoic". Proceedings of the Royal Society B: Biological Sciences 278, n.º 1724 (20 de abril de 2011): 3529–33. http://dx.doi.org/10.1098/rspb.2011.0486.
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Extinct species of Malleodectes gen. nov. from Middle to Late Miocene deposits of the Riversleigh World Heritage Area, northwestern Queensland, Australia are enigmatic, highly specialized, probably snail-eating marsupials. Dentally, they closely resemble a bizarre group of living heterodont, wet forest scincid lizards from Australia ( Cyclodomorphus ) that may well have outcompeted them as snail-eaters when the closed forests of central Australia began to decline. Although there are scincids known from the same Miocene deposits at Riversleigh, these are relatively plesiomorphic, generalized feeders. This appears to be the most striking example known of dental convergence and possible competition between a mammal and a lizard, which in the long run worked out better for the lizards.
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Turnbull, William D., Ernest L. Lundelius y Richard H. Tedford. "A Pleistocene marsupial fauna from Limeburner's Point, Victoria, Australia". Beagle : Records of the Museums and Art Galleries of the Northern Territory 9, n.º 1 (diciembre de 1992): 143–71. http://dx.doi.org/10.5962/p.263123.
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Tedford, Richard, Rod Wells y Gavin Prideaux. "Pliocene and earlier Pleistocene marsupial evolution in southeastern Australia". Alcheringa: An Australasian Journal of Palaeontology 31 (2006): 313–22. http://dx.doi.org/10.1080/03115510608619589.
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TEDFORD, RICHARD H., ROD T. WELLS y GAVIN J. PRIDEAUX. "Pliocene and earlier Pleistocene marsupial evolution in southeastern Australia". Alcheringa: An Australasian Journal of Palaeontology 30, sup1 (enero de 2006): 313–22. http://dx.doi.org/10.1080/03115510609506870.
Texto completoTesis sobre el tema "Marsupial viruses in Australia"
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Walia, Charanjiv Singh, University of Western Sydney, of Science Technology and Environment College y of Science Food and Horticulture School. "Development of a method for the identification of novel viruses in marsupials with the polymerase chain reaction (PCR)". THESIS_CSTE_SFH_Walia_C.xml, 2002. http://handle.uws.edu.au:8081/1959.7/815.
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Four main types of viruses capable of causing systemic and gastrointestinal infections, namely Coronavirus, Rotavirus, Parvovirus or Morbillivirus (Tennant et al, 1991) have been investigated in marsupials. A pilot study to develop and optimise the methodology was undertaken using Canine Coronavirus and the study was then extended to marsupials and other target viruses.In the marsupial portion of the study, a fragment of the correct size for the amplification of pol gene, 409 bp, was obtained from two different faecal samples from tammar wallaby (from Macquarie Fauna Park) and one western grey kangaroo (from Taronga Zoo). The results from tests are studied and compared. It is suggested that future further investigation should be directed at: 1/. Applying the protocols in this body of work to the testing of faecal samples from animals that have been diagnosed as positive with other diagnostic protocols. 2/. Examining more faecal samples from animals that present with active diarrhoeaMaster of Science (Hons)
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Walia, Charanjiv Singh. "Development of a method for the identification of novel viruses in marsupials with the polymerase chain reaction (PCR)". Thesis, View thesis View thesis View thesis, 2002. http://handle.uws.edu.au:8081/1959.7/815.
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Four main types of viruses capable of causing systemic and gastrointestinal infections, namely Coronavirus, Rotavirus, Parvovirus or Morbillivirus (Tennant et al, 1991) have been investigated in marsupials. A pilot study to develop and optimise the methodology was undertaken using Canine Coronavirus and the study was then extended to marsupials and other target viruses.In the marsupial portion of the study, a fragment of the correct size for the amplification of pol gene, 409 bp, was obtained from two different faecal samples from tammar wallaby (from Macquarie Fauna Park) and one western grey kangaroo (from Taronga Zoo). The results from tests are studied and compared. It is suggested that future further investigation should be directed at: 1/. Applying the protocols in this body of work to the testing of faecal samples from animals that have been diagnosed as positive with other diagnostic protocols. 2/. Examining more faecal samples from animals that present with active diarrhoea
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Mutton, Thomas Y. "Evolutionary biology of the Australian carnivorous marsupial genus Antechinus". Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/104321/6/Thomas_Mutton_Thesis.pdf.
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Antechinus is an Australian genus of small carnivorous marsupials. Since 2012, the number of described species in the genus has increased by 50% from ten to fifteen. The systematic relationships of these new species and others in the genus have not been well resolved and a broad phylogeographic study of the genus is lacking. Moreover, little ecological information is known about these new species. Therefore, the present thesis examined the evolutionary biology of Antechinus in two complimentary components. The first component aimed to resolve the systematics and phylogeography of the genus Antechinus. The second component, at a finer spatiotemporal scale, aimed to improve understanding of the autecology, habitat use and risk of extinction within the group, with a focus on the recently named buff-footed antechinus, A. mysticus and a partially sympatric congener, A. subtropicus.
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Taylor, Brendan Dominic. "Use and effectiveness of engineered road crossing-structures for wildlife in eastern Australia". Thesis, Griffith University, 2010. http://hdl.handle.net/10072/365203.
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Roads are primary agents of habitat fragmentation and transform landscapes on a global scale. Roads remove habitat and create barriers or filters to the movement of many wildlife species. Moreover, roads disrupt population processes by breaking up continuous populations into smaller, isolated subpopulations or metapopulations, which can suffer genetic drift and become more vulnerable to stochastic processes. Consequently, understanding and mitigating the impact of roads on wildlife has attracted increasing international interest in recent decades. Foremost in efforts to re-connect wildlife populations severed by roads has been the installation of crossing-structures. These are engineered structures designed to provide the opportunity for animals to safely cross either over the road (e.g. land-bridges, rope or wooden canopy-bridges) or under the road (e.g. underpasses, culverts, ecopipes). Crossing-structures enhance the permeability of roads to animal movement thereby improving the ‘functional connectivity’ of the surrounding landscape, or the degree to which the inter-fragment landscape (matrix) facilitates movement. Crossing-structures have thus become a common feature of new road projects in developed countries. Research into the efficacy of crossing-structures is very much in its infancy and has largely focused on assessing whether structures are being used by different wildlife species. As a consequence, we know very little about higher order questions pertaining to population processes, particularly whether the viability of local populations is enhanced by the deployment of crossing-structures. Furthermore, the deployment of crossing-structures has largely focused on terrestrial vertebrates and scant attention has been directed at mitigating road impacts on arboreal mammals, particularly gliding mammals (gliders). This thesis endeavours to address some of these information gaps by presenting the results of a number of investigations into wildlife use of road crossing-structures located in subtropical, eastern Australia. The topics of investigation include: i) glider use of wooden poles on a road land-bridge; ii) home-ranges of gliders residing near road crossing-structures; iii) modelling the effect of connecting habitat patches across road-gaps on glider metapopulation viability; and, vi) determining the effect of road widening on bandicoot use of highway underpasses. They represent the first studies of their kind to investigate such topics. The Australian squirrel glider Petaurus norfolcensis (Marsupialia: Diprotodontia) is a gliding marsupial distributed along the eastern seaboard of Australia. It is listed as threatened in the southern part of its geographic range due to habitat fragmentation. I investigated whether 7-m high wooden poles installed on a land-bridge could enable squirrel gliders to cross a road canopy-gap at two locations in Brisbane, the capital city of Queensland. This represented the first attempt in the world to facilitate road crossing by a gliding mammal in this way. At one location no road crossing was revealed from trapping over a 3-year period. Radio-tracking over 8 months revealed 3 occasions when animals whose home-ranges were aligned along the road had crossed the road. Hair-sampling devices revealed use of the poles at one location during 15 of 20 sampling sessions over a 3-year period, and at the second location during 6 of 6 sampling sessions over a 6-month period. Detection of hair on all poles during some sessions at both locations suggests complete crossings could occur. These observations suggest that wooden poles can be used to facilitate road-crossing by gliding mammals. Obtaining information on the use of novel road-crossing technologies such as gliding poles is a necessary first step to understanding their efficacy. However, the ultimate test of a crossing-structure’s effectiveness is in establishing to what extent has it alleviated the barrier effect of the road and prevented the extirpation of local populations. Accordingly, I utilised the population modelling program VORTEX to assess the viability of a metapopulation of squirrel gliders and Australia’s largest gliding marsupial, the greater glider (Petauroides volans), occurring in forest remnants in the fastest urbanising region of Australia. Population studies were conducted over two years within two of these forest remnants (one small, one large) connected across a major road by a land-bridge with gliding poles and rope canopy-bridges. Whereas I obtained direct evidence of squirrel glider use of the land-bridge poles, it is currently unknown whether greater gliders will use the crossing structures but available tree height and spacing do not allow a glide crossing and fences with metal flashing prevent access to the road by terrestrial and arboreal mammals. My modelling revealed that even a relatively low rate of dispersal facilitated by these structures would substantially reduce the probability of extirpation of the smaller subpopulation for both glider species. This rate of dispersal is plausible given the small distance involved (~50 m). The inclusion of wildfire as a catastrophe in my model suggests that these two remnants may encounter an undesirable level of extinction risk. This can be reduced to an acceptable level by including inter-patch movement via dispersal among other forest remnants. However, this requires connection to a very large remnant 8 km away, through a set of smaller remnants that straddle two motorways. These motorways create discontinuities in forest cover that are beyond the gliding ability of both these species and will require the deployment of crossing-structures to allow inter-patch movement. Whereas our knowledge of wildlife use of road crossing-structures has grown considerably in recent years, little is known about the effect that road widening may have on patterns of use by target fauna. To address this, I investigated the effect that duplicating a highway had on bandicoot (Marsupialia: Peramelemorphia) use of underpasses at Brunswick Heads in north east New South Wales (NSW). This study represented one of the first of its kind in Australia and spanned the period of pre and post-construction over an eight year period. Evidence from trapping data showed that individuals of the two bandicoot species present at the study site (i.e. Isoodon macrourus and Perameles nasuta) incorporated both sides of the road corridor into their home ranges and that the majority of movements were likely associated with foraging. The trapping data also demonstrated spatial overlap between and within sexes and congeners suggesting that underpasses were functionally available to resident animals and were each being used by multiple individuals. Despite this, gaining clear insights on the effect that road-widening had on underpass use by bandicoots was confounded by drought, loss of high quality habitat, a decline in bandicoot abundance, the presence of foxes and different design characteristics of new underpasses. Further surveys are required at Brunswick Heads to elucidate this issue. The results of my investigations on bandicoot and glider use of road crossing-structures provide strong support for the need to manage road impacts on wildlife at multiple scales. At the patch or site-level, a number of enhancements are required to improve the functionality of the investigated crossing-structures and to make the study sites more amenable to the target species. At the landscape-level, management needs to focus on improving functional connectivity in the surrounding landscape to strengthen the viability of local metapopulations. This will require the combination of habitat restoration works, wildfire control and the deployment of crossing structures where large roads and motorways breach forest cover. In the case of gliders, the deployment of crossing-structures can be achieved rapidly and cost-effectively by installing gliding poles along motorway edges and in median strips at locations where forest cover is breached. Future research at these study sites needs to continue for much longer periods (i.e. 5-10 years) and incorporate genetic techniques. This will assist in improving our understanding of the isolation effects of road barriers and whether or not gene flow is restored by the installation of crossing-structures. This should be routinely combined with viability assessments (e.g. PVA) to determine how populations are affected by roads and whether they might benefit from crossing structures. Research is also required to provide insights to dispersal behaviour, particularly for gliders, and the likely use of road-crossing structures. Loss of habitat and habitat connections is continuing in my study landscapes and this is likely to have dire consequences for wildlife if land managers are unable to retain appropriate habitat cover with corridors and install effective wildlife road crossing-structures where large roads bisect wildlife habitat.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Williams, Catherine F. (Catherine Felicia). "Studies on the Australian bluetongue viruses / by Catherine F. Williams". Thesis, The University of Sydney, 1994. https://hdl.handle.net/2123/27530.
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Bluetongue disease is an infectious, noncontagious, arthropod-borne disease transmitted by certain species of midges belonging to the genus Culicoides. The causative agent, bluetongue virus (BTV), is a member of the Reoviridae family and orbivirus genus. Although mostly affecting sheep, other ruminants including wildlife can be infected.
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au, M. Banazis@murdoch edu y Michael Banazis. "Development of tools for surveillance of Coxiella burnetii in domestic ruminants and Australian marsupials and their waste". Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090707.114918.
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The aim of this study was to develop improved methods to detect viable Coxiella burnetii in wastes from livestock production. The impetus for this work arose because there is a significant risk of infection for humans attributed to contact with waste products from the livestock production industry. This situation is further compounded by the lack of suitable tools to detect viable C. burnetii in these wastes. In addition, effective disinfection strategies for livestock wastes are also required to reduce the risk of infection with C. burnetii for individuals that come into contact with these waste products.
A quantitative real-time PCR system (qPCR) with high sensitivity and specificity was developed to detect the C. burnetii in environmental samples associated with domestic ruminants and native Australian marsupials. Different detection chemistries and procedures were evaluated based on their sensitivity, specificity and reproducibility. Overall it was found that the TaqMan PCR targeting the IS1111a locus provided the most sensitive and reproducible test. The Geneworks PowerSoil(tm) DNA isolation kit provided the best compromise between reproducibility and recovery of DNA from livestock wastes. When combined, the IS1111a TaqMan qPCR and Geneworks PowerSoil DNA Extraction Kit provided a test which was capable of detecting as few as two C. burnetii genome equivalents in 0.2g of soil or faeces.
Coxiella burnetii has been shown to display extreme resistance to environmental exposure. Therefore, assessment of the viability of the organism in environmental matrices is more useful for risk assessment programs than detection of DNA alone. A quantitative reverse transcriptase PCR was developed that was able to detect viable C. burnetii cells in soil. The sensitivity of the assay was enhanced by heat-treating the soil samples prior to extraction of RNA.
The factor most often associated with transfer of C. burnetii to humans is exposure to livestock or their waste. Therefore, decontamination of waste from livestock production industries is a key factor in preventing outbreaks of Q fever. A system was developed to determine the efficacy of various disinfectant treatments against the environmental pathogen C. burnetii. Treatments evaluated included sodium hypochlorite, ozone, ultraviolet light, peracetic acid (PAA), and Virkon S®. Sodium hypochlorite at a concentration of 0.1 mM reduced the infectivity of C. burnetii by over 92% while treatment with the same sodium hypochlorite concentration in wastewater showed significantly reduced efficacy. Despite this reduced potency, sodium hypochlorite is still useful for control of C. burnetii in the liquid waste of animal production.
Commercially available ELISA and CFT assays exist for ruminants but there are no immunological tests available for detecting C. burnetii in marsupials even though Australian marsupials are known to be susceptible to C. burnetii. An indirect ELISA for detecting anti-Coxiella antibodies in kangaroos was developed. Paired serum and faecal samples were taken from 379 ruminants from Western Australia and the serum was tested with a commercially available ELISA and the complement fixation test while the faeces was tested using the qPCR developed during this study. Paired serum and faecal samples were taken from 343 kangaroos from WA and were tested with the antibody-ELISA developed during this study and by qPCR. A very low prevalence of anti-Coxiella antibodies was observed in the ruminants sampled and results from immunological tests correlated poorly with qPCR data. The development of an ELISA for use with kangaroo serum was problematic because of the lack of reference sera from animals known to be infected with C. burnetii. Despite this results from the ELISA developed suggested that the apparent seroprevalence in the WA animals surveyed was approximately 34%. Results from testing kangaroo faeces with the qPCR correlated poorly with the results from the antibody-ELISA. These data suggest that kangaroos may be a significant reservoir of C. burnetii in Western Australia and due to cohabitation of kangaroos and domestic ruminants, may provide a link between the wildlife and domestic cycles of C. burnetii.
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Smith, Steven. "The Application of Molecular Genetics to Species Recovery Programs: Case Studies of Two Marsupial Reintroductions in Australia". Thesis, Griffith University, 2007. http://hdl.handle.net/10072/365972.
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An increasing number of endangered species have reached the threshold prompting management decisions to commence captive breeding and reintroduction. Such intervention is costly and requires a substantial investment of resources that might otherwise be spent on alternate conservation options. It is important, therefore, that such measures make use of all available information to ensure the success of the reintroduction effort, not just in the short-term but also well into the future. The diverse range of elements to be considered include habitat factors, number and sex ratio of founders, number of populations to establish, source populations to use, timing of releases and the need to supplement the populations. All of these factors can benefit through input from molecular genetic data to improve the quality of information used in decision making. Levels of genetic variation are strongly correlated with population fitness and their potential for long-term persistence. For this thesis I examined levels of genetic diversity at neutral and functional regions of the genome for two endangered species of Australian marsupials: the western barred bandicoot, Perameles bougainville; and Queensland populations of the greater bilby, Macrotis lagotis.
These two species are under threat from similar processes: habitat destruction and modification for agriculture; predation by foxes and feral cats; changes to traditional fire regimes and competition with introduced pest species. Since European settlement, P. bougainville has become extinct on the mainland and now exists on just two islands in Shark Bay, Western Australia. Macrotis lagotis has suffered a range contraction of over 80% and the Queensland population has become disjointed from other populations to the west. Reintroduction efforts are under way for both species but, until now, the projects have not made use of molecular genetic data to inform their management decisions. I have used marker systems from nuclear microsatellite DNA, mitochondrial control region DNA and the functionally important major histocompatability complex (MHC) to assess levels of genetic diversity in natural, captive and reintroduced populations of both species. DNA was sourced from ear-tissue for P. bougainville and from ear-tissue and faecal pellets for M. lagotis.
The levels of microsatellite diversity for the two natural populations of P. bougainville (Bernier Island: HE = 0.27± 0.1, A = 1.8± 0.3; Dorre Island: HE = 0.31± 0.1, A = 2.2± 0.4) were low compared to other marsupials and significantly lower than that recorded for the natural Queensland population of M. lagotis (Astrebla Downs: HE = 0.76 ± 0.03, A = 4.31 ± 0.3). In all cases, the diversity of captive and reintroduced populations was reduced relative to their source populations except for the Dryandra captive population of P. bougainville (HE = 0.54± 0.1, A = 2.69± 0.2) which was founded following a mixed breeding strategy using individuals sourced from both natural island populations. Distribution of mtDNA haplotypes among geographical regions indicated that, for each species, populations could be combined in captive breeding programs without compromising distinct evolutionary lineages. Design of MHC assays proved difficult for M. lagotis, but for P. bougainville two separate MHC class II alleles were identified. These two alleles were fixed across all individuals in all populations suggesting that they may represent two paralogous loci in P. bougainville and that MHC diversity is unusually low for this species.
I have recommended that the recovery programs for both species be expanded to incorporate regular monitoring of molecular data to ensure that genetic diversity is retained and maximised in all populations. Where possible, the natural populations should be maintained as “pure lines” to increase overall species genetic diversity but the captive and reintroduced populations should make use of supplementary individuals from a mixture of sources to maximise variation and thus the adaptive potential of these populations in the novel environments to which they are being introduced.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Faculty of Science, Environment, Engineering and Technology
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McCarthy, Marilyn Rae. "Speaking the unspeakable : the themes, issues and concerns of seven HIV/AIDS educators in South Australia /". full text, 1993. https://www.library.health.sa.gov.au/Portals/0/speaking-the-unspeakable-the-themes-1993.pdf.
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Thesis (M. Ed.)--University of South Australia, 1993."Report of a thesis submitted for a masters in Education, Human Resource Studies August 1993"--Cover. Includes bibliographical references (leaf 178-188).
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Ellis, Trevor Maxwell. "Studies of caprine arthritis-encephalitis viruses, associated diseases and their control in Western Australia". Thesis, Ellis, Trevor Maxwell (1986) Studies of caprine arthritis-encephalitis viruses, associated diseases and their control in Western Australia. PhD thesis, Murdoch University, 1986. https://researchrepository.murdoch.edu.au/id/eprint/53421/.
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The clinical signs and pathology of chronic arthritis-synovitis and chronic interstitial pneumonia in goats in Western Australia were described.
Retroviruses were isolated by explant culture techniques from synovial membrane of joints with arthritis, lung tissue of goats with chronic interstitial pneumonia and lung tissue of goats with arthritis but no pneumonic lesions. Similar viruses were also recovered from peripheral blood leucocytes, alveolar macrophages and cells centrifuged from colostrum of goats with arthritis, or arthritis and chronic interstitial pneumonia, by co-cultivation of these cells with normal goat synovial membrane (GSM) cells.
The physico-chemical characteristics of the isolated retroviruses were similar to those previously reported for caprine arthritis encephalitis virus (CAEV) which was initially isolated from joint lesions of goats in the USA. These similarities included cultural and morphological characteristics, the presence of RNA-dependent DNA polymerase in the virion, a buoyant density of 1.15 g/ml, similarities in protein composition and antigenic relationship to maedi-visna virus. One property distinguishing the local virus isolates from those described in the USA was the mechanism of virus-induced cell fusion. CAEV-induced cell fusion was previously reported to require de novo synthesis of viral protein in infected cells. Local isolates of CAEV induced cell fusion of GSM cells before progeny virus was detected and de novo synthesis of virus coded proteins was not required.
The physico-chemical characteristics of CAEV isolates from lungs of goats with chronic interstitial pneumonia and joints of ii goats with chronic arthritis were indistinguishable. Inoculation of CAEV-free goats with viruses isolated from either type of lesion induced arthritis-synovitis lesions which were similar to those in goats with naturally-occurring disease. None of the isolates from either lung or joint tissue induced interstitial pneumonia in experimentally infected goats, although there was evidence which suggested that lungworms or other granuloma-inducing processes interacted with CAEV to produce chronic interstitial pneumonia.
Enzyme linked immunosorbent assays (ELISA), agarose gel immunodiffusion (AGIO) and serum neutralisation tests were developed to detect CAEV-antibody in goats. Goats with antibody to CAEV were persistently infected with CAEV. Serological surveys of goats in Western Australia indicated a high prevalence of infection in dairy goats and a low prevalence in Angora goats. There was no evidence of CAEV infection in feral goats.
All CAEV isolates shared common ELISA and AGIO antigens but antigenic heterogeneity was demonstrated using serum neutralisation tests. Antigenic variation of CAEV was shown to occur during persistent infection of goats although the significance of this variation in the pathogenesis of CAEV-induced lesions appeared to be minimal.
Ingestion of colostrum and milk from infected does was shown to be a major method of transmission of CAEV, although the virus was also transmitted between older goats during prolonged close contact or mating. This information was used to devise a programme which was successfully used to eradicate CAEV infection from a herd with a high prevalence of CAEV infection.
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Razali, Karina National Centre in HIV Epidemiology & Clinical Research Faculty of Medicine UNSW. "Estimates and projections of HIV and Hepatitis C virus in Australia and the Asia-Pacific region". Publisher:University of New South Wales. National Centre in HIV Epidemiology & Clinical Research, 2008. http://handle.unsw.edu.au/1959.4/41095.
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The use of mathematical models in studying disease epidemics can be diverse, from the focused study of the role of a single determinant of the epidemic, or to the overall estimation of morbidity and mortality. In using simple deterministic models, a balance is struck between biological and social complexities, and the high data input demands of mathematical models. This thesis aims to apply the use of deterministic mathematical models to the studies of HIV and hepatitis C epidemiology in the Asia-Pacific region. In Australia, about 85% of reported HIV cases are among homosexual men. Casual homosexual partnerships made up 40% of incident HIV cases in 1995 increasing to 65% in 2004. In the state of New South Wales, it was estimated that over 7,500 people were living with HIV/AIDS in 2005, increasing to over 10,000 by 2016 with existing levels of intervention. Intervention measures were estimated to have prevented some 44,500 cases, the majority being among injecting drug users through the Needle and Syringe Programmes. Models for the HIV epidemics in developing countries were also developed incorporating multiple routes of HIV transmission. For Papua New Guinea, it was estimated 64,000 people were living with HIV/AIDS in 2005, rising to over 500,000 by 2025 with current levels of intervention. High levels of interventions, in particular increased condom use, will be required to achieve a stabilisation or reduction in HIV prevalence. In East Timor, the HIV epidemic is still in the early stages with 138 people estimated to be living with HIV/AIDS, rising to 5,000 by 2025 with minimal intervention. For HCV, models of the epidemic in Australia showed HCV incidence peaking in 1999, followed by a decline reaching 9,700 incident cases in 2005. Of 197,000 estimated chronic HCV cases in 2005, 58% had stage F 0/1 liver disease, 15% F 2/3 liver disease, and 2% HCV-related cirrhosis. Models estimated 210 and 105 people developed HCV-related liver failure and hepatocellular carcinoma, respectively. Comparisons of modelled HCV long-term sequelae projections with linkage data showed relatively good agreement, despite discrepancies in liver-related deaths. To decrease the number of chronic HCV, at least a tripling of treatment coverage would be required. These models provide estimates of the current levels of epidemics as well as projections of future scenarios under different intervention strategies, which have an important role in the planning of strategies, as well as assessment of previous epidemic conditions.
Libros sobre el tema "Marsupial viruses in Australia"
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Western Australia. Communicable Disease Control Branch. HIV/AIDS & sexually transmitted infections: Education & prevention plan for Western Australia. Shenton Park, W.A: Communicable Disease Control Branch, Dept. of Health, 2002.
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HIV, AIDS and Society Conference (3rd 1995 Sydney, N.S.W.). HIV, AIDS and society 1995: Social science, from theory to practice : proceedings of the 3rd HIV, AIDS and Society Conference, Macquarie University, Sydney, Australia, 11-12 July, 1995. Sydney: National Centre in HIV Social Research, Macquarie University, 1995.
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Lithgow, John y Jack E. Davis. Marsupial Sue Presents "The Runaway Pancake". Simon & Schuster Books for Young Readers, 2008.
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Lock, Marianne y Chris Daniels. Koala: A First Field Guide to the Cuddly Marsupial from Australia. Priddy Books, 2023.
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Lock, Marianne, Chris Daniels y Neon Squid. Koala: A First Field Guide to the Cuddly Marsupial from Australia. St. Martin's Press, 2023.
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Glen, Alistair y Christopher Dickman, eds. Carnivores of Australia. CSIRO Publishing, 2014. http://dx.doi.org/10.1071/9780643103177.
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The Australian continent provides a unique perspective on the evolution and ecology of carnivorous animals. In earlier ages, Australia provided the arena for a spectacular radiation of marsupial and reptilian predators. The causes of their extinctions are still the subject of debate. Since European settlement, Australia has seen the extinction of one large marsupial predator (the thylacine), another (the Tasmanian devil) is in danger of imminent extinction, and still others have suffered dramatic declines. By contrast, two recently-introduced predators, the fox and cat, have been spectacularly successful, with devastating impacts on the Australian fauna.
Carnivores of Australia: Past, Present and Future explores Australia's unique predator communities from pre-historic, historic and current perspectives. It covers mammalian, reptilian and avian carnivores, both native and introduced to Australia. It also examines the debate surrounding how best to manage predators to protect livestock and native biodiversity.
Wildlife managers, academics and postgraduate students will benefit from the most up-to-date synthesis by leading researchers and managers in the field of carnivore biology. By emphasising Australian carnivores as exemplars of flesh-eaters in other parts of the world, this book will be an important reference for researchers, wildlife managers and students worldwide.
Winner of a 2015 Whitley Awards Certificate of Commendation for Zoological Text.
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Butcher, Barry y Barry W. Butcher. Of Vets, Viruses and Vaccines: The Story of CSIRO's. CSIRO Publishing, 2000.
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Patent, Dorothy Hinshaw. Saving the Tasmanian Devil: How Science Is Helping the World's Largest Marsupial Carnivore Survive. Houghton Mifflin Harcourt Publishing Company, 2019.
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Butcher, Barry W. Of Vets, Viruses and Vaccines: The Story of the Animal Health Research Laboratory, Parkville. CSIRO Publishing, 2000.
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Steiger, Diego. Koala Hiding Calendar 2022: Annual Calendar for Animal Lovers and Fans of the Cute Marsupial from Australia. Independently Published, 2021.
Buscar texto completoCapítulos de libros sobre el tema "Marsupial viruses in Australia"
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Poon, Myra, William D. Rawlinson y Maria E. Craig. "Diabetes and Viruses in Australia and the Asia-Pacific Region". En Diabetes and Viruses, 207–17. New York, NY: Springer New York, 2012. http://dx.doi.org/10.1007/978-1-4614-4051-2_21.
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Kerr, Peter J., Robyn N. Hall y Tanja Strive. "Viruses for Landscape-Scale Therapy: Biological of in Australia". En Methods in Molecular Biology, 1–23. New York, NY: Springer US, 2020. http://dx.doi.org/10.1007/978-1-0716-1012-1_1.
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Mackenzie, John S., Michael Poidinger, Michael D. Lindsay, Roy A. Hall y Leanne M. Sammels. "Molecular Epidemiology and Evolution of Mosquito-Borne Flaviviruses and Alphaviruses Enzootic in Australia". En Molecular Evolution of Viruses — Past and Present, 153–65. Boston, MA: Springer US, 1996. http://dx.doi.org/10.1007/978-1-4613-1407-3_14.
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Belcher, Chris. "The largest surviving marsupial carnivore on mainland Australia: the Tiger or Spotted-tailed QuollDasyurus maculatus, a nationally threatened, forest-dependent species". En Conservation of Australia's Forest Fauna, 612–23. P.O. Box 20, Mosman NSW 2088: Royal Zoological Society of New South Wales, 2004. http://dx.doi.org/10.7882/fs.2004.034.
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Solé, Ricard y Santiago F. Elena. "Epidemics". En Viruses as Complex Adaptive Systems, 120–48. Princeton University Press, 2018. http://dx.doi.org/10.23943/princeton/9780691158846.003.0005.
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It has been argued that epidemics have played a major role in human history. For example, the arrival of the British in Australia triggered a deadly wave of smallpox infections, with the estimated death of half of the indigenous Australians. The same virus wiped out the population of Easter Island, and measles eliminated a third of the inhabitants of Fiji. New threats have also emerged as human populations explode and pressure on ecosystems crosses sustainability thresholds. In order to understand how to deal with epidemics and eradicate them, there is a need to first understand how they spread. This chapter begins with a discussion of epidemic modeling, specifically the SIS model. It then covers the SIS model in space and graphs, modeling HIV-1 transmission, and halting viruses in scale-free networks.
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Pierotti, Raymond y Brandy R. Fogg. "“Dingo Makes Us Human”". En The First Domestication. Yale University Press, 2017. http://dx.doi.org/10.12987/yale/9780300226164.003.0007.
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This chapter examines the distinctive situation in Australia, where Homo sapiens and dingoes coexisted for several thousand years. These two species were the only large placental mammals on a continent dominated by marsupial mammals and large reptiles. The dingo group represents a unique branch of canid domestication; they live independently, either wild or semi-wild, but also associate with humans, including hunting and even sleeping with them. Dingoes demonstrate that it is possible for an animal previously domesticated to live and reproduce successfully without humans. The relationship between dingoes and the Aboriginals provides a model for investigating the process of domestication in canids, strongly suggesting that domestication is a multistep and potentially reversible process. It also reveals how a canid can exist in a situation where it may or may not choose to live with humans, functioning well in either case.
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Ibrahim, Chourouk, Salah Hammami, Eya Ghanmi y Abdennaceur Hassen. "Emerging Human Coronaviruses (SARS-CoV-2) in the Environment Associated with Outbreaks Viral Pandemics". En Wastewater Treatment [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.103886.
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In December 2019, there was a cluster of pneumonia cases in Wuhan, a city of about 11 million people in Hubei Province. The World Health Organization (WHO), qualified CoVid-19 as an emerging infectious disease on March 11, 2020, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which spreads around the world. Coronaviruses are also included in the list of viruses likely to be found in raw sewage, as are other viruses belonging to the Picornaviridae family. SRAS-CoV-2 has been detected in wastewater worldwide such as the USA, France, Netherlands, Australia, and Italy according to the National Research Institute for Public Health and the Environment. In addition, the SARS-CoV-2 could infect many animals since it has been noticed in pigs, domestic and wild birds, bats, rodents, dogs, cats, tigers, cattle. Therefore, the SARS-CoV-2 molecular characterization in the environment, particularly in wastewater and animals, appeared to be a novel approach to monitor the outbreaks of viral pandemics. This review will be focused on the description of some virological characteristics of these emerging viruses, the different human and zoonotic coronaviruses, the sources of contamination of wastewater by coronaviruses and their potential procedures of disinfection from wastewater.
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"Anogenital warts". En Oxford Handbook of Genitourinary Medicine, HIV, and Sexual Health, editado por Laura Mitchell, Bridie Howe, D. Ashley Price, Babiker Elawad y K. Nathan Sankar, 291–304. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780198783497.003.0023.
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Warts are caused by human papilloma viruses (HPV) and remain one of the most common STIs, accounting for 16% of new diagnoses in UK GUM clinics in 2015. Introduction of the quadrivalent HPV vaccine for girls has seen a steady decline of warts in young women and heterosexual men. Currently in the UK, HPV vaccination is offered to men who have sex with men <46 years old who access sexual health clinics, but national guidelines recommend routine vaccination to all boys as well as girls. Some countries such as Australia have already introduced vaccination for girls and boys, and there is hope that the UK will follow suite. This chapter details epidemiology, natural history, diagnosis, and principles of management of anogenital warts, including management in pregnancy and
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van Santen, Rutger, Djan Khoe y Bram Vermeer. "Preparing for Pandemics". En 2030. Oxford University Press, 2010. http://dx.doi.org/10.1093/oso/9780195377170.003.0030.
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The first draft of this chapter was written before the pandemic alert for the 2009 flu was launched. Since then, terms such as swine flu, Mexican flu, or H1N1 were constantly in the headlines. We witnessed the first really worldwide outbreak of a new influenza strain. Events went faster than we foresaw in our original text. We had started the chapter with an imaginary scenario of an outbreak in 2013 not in Mexico but in the East Java, Indonesia, city of Malang. It was not really meant as a prediction but merely a little story to show the consequences of an outbreak. We wanted to show how disruptive the outbreak of a new disease might be. We described all the things that we are now familiar with: doctors who aren’t particularly worried in the beginning; people that live close to their animals and pick up viruses; patients in hospitals with high fever and severe cough; pharmaceutical companies anxious to peddle expensive vaccines. Then we invented some struggle between the Indonesian authorities and the World Health Organization (WHO) about blood samples. That reflects the reluctance of developing nations to cooperate in the production of vaccines they can never afford. In our story, the rest of the world ignored this imaginary outbreak and was oblivious to the rising death toll and the diplomatic wrangling. That’s just like the start of the 2009 flu that probably haunted Mexican villages for many weeks unreported. In our story, the silence was broken when two nurses died in Perth, Australia. The media seized on the story immediately with yelling headlines. In the week that followed, dozens of new cases were reported in Indonesia, Australia, and Singapore, together with the first suspected case in New York. Then there follows all the health humdrum that we are now so familiar with. The WHO has got hold of the flu virus and is preparing to produce a new vaccine. However, the epidemic spreads like an oil slick with the virus striking one major city after another. Antivirals change hands over the Internet for huge sums despite doctors’ warnings that the drugs only work if administered within a few hours of infection.
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Woodcock, Leone E. y San Murugesan. "Gender Differences in Ethics Perceptions in Information Technology". En Information Security and Ethics, 3433–41. IGI Global, 2008. http://dx.doi.org/10.4018/978-1-59904-937-3.ch230.
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Greater emphasis is now placed on ethics in information technology (IT) which covers a broad range of issues such as privacy, honesty, trustworthiness, software reliability, data storage, the environment, security breaches, hacking, viruses, and acknowledging the intellectual property of others. Further, legal aspects tend to overlap ethics perceptions. For example, issues such as copying computer programs, music CDs, images, or videos are more than just ethical problems; they also pose legal problems. The ethical dimensions also extend to issues such as computer crime and fraud, information theft, and unauthorized information dissemination. These ethical issues are becoming more complex as continuing advances in IT present many new ethical situations and fresh dilemmas. Developments such as the Internet, electronic commerce, and wireless/mobile communications present a new set of ethical issues and challenge current of codes of ethics, copyright laws, and their authors. In addition, computer users’ ethical standards may also vary from one situation to another (Wikipedia, 2005). What is ethical is subjective, and more so in the areas of IT. Perceptions of ethics in IT vary to a degree from individual to individual. Further, there seems to be significant differences in the perception of ethics among males and females. According to Adam (2000), male and female judgment is most often influenced by their personal values and whether an action is considered legal. Woodcock (2002) conducted a study on ethical perceptions among 405 male and female students from universities, technical colleges, and schools in North-Eastern Australia and found significant differences in some ethical situations between males and females. This article presents common issues and dilemmas that confront IT professionals, students, and the general community. In particular, it presents gender differences in perceptions of ethics and legalities in IT and highlights the different ethical perceptions of male and female students. These insights are particularly significant as the ethical beliefs and perceptions that students have may influence their ethical behaviors during their working careers.
Actas de conferencias sobre el tema "Marsupial viruses in Australia"
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Seidl, S. "SCREENING PROCEDURES TO PREVENT TRANSMISSION OF HEPATITIS B, NON-A,NON-B, AND AIDS BY BLOOD TRANSFUSION". En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644753.
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Although the number of infectious agents capable of being transmitted through blood and blood products is vast, only a few cause problems in recipients of a magnitude which warrants the need for screening tests. The most important agents are Hepatitis B Virus (HBV), Hepatitis non-A,non-B (HNANB) - agents causing posttransfusion hepatitis (PTH) and the human immundeficiency viruses (HIV) responsible for transfusion associated AIDS (TAA).PTH: Prospective studies in open-heart-surgery patients demonstrated a high prevalence (8-17%) *in Spain, Italy, the United States and Israel whereas low percentages (2-5%) were observed in Australia, Finland and West-Germany. Among haemophiliacs acute and chronic hepatitis is a rather frequent complication. Serologic markers of HBV infection have been observed in the majority of patients. Since HBsAg screening has been introduced most cases of PTH (>90%) are due to infection with HNANB-agents. For this type of hepatitis no specific assay exists. It has been suggested that surrogate tests (ALT, anti-HBc screening) might serve as interim screening measure. In prospective studies in the USA a correlation has been observed between donor ALT and recipient hepatitis, but not more than 30% of PTH can be prevented at a loss of 1,5 to 3,0% of the donor population. Similar data have been reported when blood donors were screened for anti-HBc. There was a significantly higher incidence of PTH in recipients receiving at least one unit of anti HBc positive blood. This was recently confirmed in a study in which patients received blood with ALT-levels below 30 IU/ml. The incidence of HNANB was 2,1% after transfusion with anti HBc negative blood whereas 10,1% developed HNANB when anti HB positive blood was transfused (P=< 0.0001). However, these two markers (ALT, anti HBc) do not identify the same NANB carrier population. - ALT screening and testing for anti-HBc have been recently instituted in the USA as “surrogate tests” for detecting HNANB carriers.TAA: Among the total number of AIDS cases there ist a small percentage caused by transfusion of blood and blood products. In the USA approximately 2% of TAA have been reported, 1 % of AIDS patients are haemophiliacs but the majority of haemophiliacs are HIV-antibody positive. According to a survey of the Council of Europe (March 1986) the percentages of HIV positive European haemophiliacs varies between 4 to 8% (Belgium, Norway) and 30 to 60% in other European countries. The number of TAA-cases is around 1%, AIDS among European haemophiliacs has been observed up to 5% of the total AIDS cases. - Screening for HIV antibodies in blood donors was introduced in most European countries and the USA in early summer 1985, but several thousands of recipients of HIV positive blood (issued before) are now virus carriers. This has been confirmed in “look back” programmes: A substantial number of recipient (50 to 90%) has been found to be HIV positive.-A major disadvantage of the HIV antibody test is the fact that antibodies appear several weeks after infection. The gap between infection and detecting HIV antibodies may be reduced by an antigen test, which recognizes the HIV infection as early as two weeks after infection. - The recent detection of HIV 2 implies the necessity of developing tests for the identification of variants of HIV.
Informes sobre el tema "Marsupial viruses in Australia"
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Levin, Ilan, John Thomas, Moshe Lapidot, Desmond McGrath y Denis Persley. Resistance to Tomato yellow leaf curl virus (TYLCV) in tomato: molecular mapping and introgression of resistance to Australian genotypes. United States Department of Agriculture, octubre de 2010. http://dx.doi.org/10.32747/2010.7613888.bard.
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Tomato yellow leaf curl virus (TYLCV) is one of the most devastating viruses of cultivated tomatoes. Although first identified in the Mediterranean region, it is now distributed world-wide. Sequence analysis of the virus by the Australian group has shown that the virus is now present in Australia. Despite the importance of the disease and extensive research on the virus, very little is known about the resistance genes (loci) that determine host resistance and susceptibility to the virus. A symptom-less resistant line, TY-172, was developed at the Volcani Center which has shown the highest resistance level among all tested varieties. Preliminary results show that TY-172 is a good candidate to confer resistance to both TYLCV and to Tomato leaf curl virus (ToLCV) in Queensland conditions. Furthermore, Segregation analysis has previously indicated that the resistance is determined by 2-3 genes. In this proposal we aimed to substantiate that TY-172 can contribute to resistance breeding against TYLCV in Queensland, to develop DNA markers to advance such resistance breeding in both Israel and Queensland, and to exploit these markers for resistant breeding in Australian and Israeli lines. To map quantitative trait loci (QTLs) controlling TYLCVresistance in TY172, appropriate segregating populations were analyzed using 69 polymorphic DNA markers spanning the entire tomato genome. Results show that TYLCV resistance in TY172 is controlled by a previously unknown major QTL, originating from the resistant line, and four additional minor QTLs. The major QTL, termed Ty-5, maps to chromosome 4 and accounts for 39.7-to-46.6% of the variation in symptom severity among segregating plants (LOD score: 33-to-35). The minor QTLs, originated either from the resistant or susceptible parents, were mapped to chromosomes 1, 7, 9 and 11, and contributed 12% to the variation in symptom severity in addition to Ty-5. Further analysis of parental lines as well as large F₁, BC₁F₁, F₂ and BC₁F₂ populations originating from crosses carried out, in reciprocal manner, between TY172 and the susceptible processing line M-82 (LA3475) during spring-summer 2010, indicated that: (1) the minor QTLs we have previously identified are in effect not reproducible, (2)Ty-5 alone can yield highly resistant plants with practically no extra-chromosomal effects, and (3) the narrow-sense heritability estimate of resistance levels, attributed to additive factors responsive to selection, does not significantly deviate from 1. All of these results point to Ty-5 as the sole resistance locus in TY172 thus significantly increasing the likelihood of its successful molecular dissection. The DNA markers developed during the course of this study were transferred together with the TY172 genotype to Queensland. TY172 was crossed to a panel of Australian genotypes and the resulting populations were subjected to segregation analysis. Results showed that resistant locus, Ty-5, is highly reproducible in the Australian conditions as well. The Australian group was also able to make improvements to the marker assays by re-designing primer pairs to provide more robust PCR fragments. The Ty-5 locus has now been introgressed into elite Australian germplasm and selection for TYLCV resistance has begun. Cumulatively, our results show that Ty-5 can be effectively used, together with the TY172 genotype to expedite TYLCV resistance breeding and improve our understanding of the genetics that underline the response of tomato to TYLCV. Contributions to agriculture include: (1) the development of tools for more efficient resistance breeding, allowing the incorporation of resistance to local tomato varieties in Australia, Israel and elsewhere; and (2) establish a solid framework for a future attempt to clone the genes that encode such resistance. The latter will enable to decipher the resistance mechanisms that could be applied to other geminiviruses in tomato and possibly in other plant species.
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Klement, Eyal, Elizabeth Howerth, William C. Wilson, David Stallknecht, Danny Mead, Hagai Yadin, Itamar Lensky y Nadav Galon. Exploration of the Epidemiology of a Newly Emerging Cattle-Epizootic Hemorrhagic Disease Virus in Israel. United States Department of Agriculture, enero de 2012. http://dx.doi.org/10.32747/2012.7697118.bard.
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In September 2006 an outbreak of 'Bluetongue like' disease struck the cattle herds in Israel. Over 100 dairy and beef cattle herds were affected. Epizootic hemorrhagic disease virus (EHDV) (an Orbivirusclosely related to bluetongue virus (BTV)), was isolated from samples collected from several herds during the outbreaks. Following are the aims of the study and summary of the results: which up until now were published in 6 articles in peer-reviewed journals. Three more articles are still under preparation: 1. To identify the origin of the virus: The virus identified was fully sequenced and compared with the sequences available in the GenBank. It appeared that while gene segment L2 was clustered with EHDV-7 isolated in Australia, most of the other segments were clustered with EHDV-6 isolates from South-Africa and Bahrain. This may suggest that the strain which affected Israel on 2006 may have been related to similar outbreaks which occurred in north-Africa at the same year and could also be a result of reassortment with an Australian strain (Wilson et al. article in preparation). Analysis of the serological results from Israel demonstrated that cows and calves were similarly positive as opposed to BTV for which seropositivity in cows was significantly higher than in calves. This finding also supports the hypothesis that the 2006 EHD outbreak in Israel was an incursive event and the virus was not present in Israel before this outbreak (Kedmi et al. Veterinary Journal, 2011) 2. To identify the vectors of this virus: In the US, Culicoides sonorensis was found as an efficient vector of EHDV as the virus was transmitted by midges fed on infected white tailed deer (WTD; Odocoileusvirginianus) to susceptible WTD (Ruder et al. Parasites and Vectors, 2012). We also examined the effect of temperature on replication of EHDV-7 in C. sonorensis and demonstrated that the time to detection of potentially competent midges decreased with increasing temperature (Ruder et al. in preparation). Although multiple attempts were made, we failed to evaluate wild-caught Culicoidesinsignisas a potential vector for EHDV-7; however, our finding that C. sonorensis is a competent vector is far more significant because this species is widespread in the U.S. As for Israeli Culicoides spp. the main species caught near farms affected during the outbreaks were C. imicolaand C. oxystoma. The vector competence studies performed in Israel were in a smaller scale than in the US due to lack of a laboratory colony of these species and due to lack of facilities to infect animals with vector borne diseases. However, we found both species to be susceptible for infection by EHDV. For C. oxystoma, 1/3 of the Culicoidesinfected were positive 11 days post feeding. 3. To identify the host and environmental factors influencing the level of exposure to EHDV, its spread and its associated morbidity: Analysis of the cattle morbidity in Israel showed that the disease resulted in an average loss of over 200 kg milk per cow in herds affected during September 2006 and 1.42% excess mortality in heavily infected herds (Kedmi et al. Journal of Dairy Science, 2010). Outbreak investigation showed that winds played a significant role in virus spread during the 2006 outbreak (Kedmi et al. Preventive Veterinary Medicine, 2010). Further studies showed that both sheep (Kedmi et al. Veterinary Microbiology, 2011) and wild ruminants did not play a significant role in virus spread in Israel (Kedmi et al. article in preparation). Clinical studies in WTD showed that this species is highly susceptibile to EHDV-7 infection and disease (Ruder et al. Journal of Wildlife Diseases, 2012). Experimental infection of Holstein cattle (cows and calves) yielded subclinical viremia (Ruder et al. in preparation). The findings of this study, which resulted in 6 articles, published in peer reviewed journals and 4 more articles which are in preparation, contributed to the dairy industry in Israel by defining the main factors associated with disease spread and assessment of disease impact. In the US, we demonstrated that sufficient conditions exist for potential virus establishment if EHDV-7 were introduced. The significant knowledge gained through this study will enable better decision making regarding prevention and control measures for EHDV and similar viruses, such as BTV.