Search

BLUETONGUE VIRUS SEROTYPE 16 DETECTION IN NSW: In coastal New South Wales (NSW), bluetongue virus (BTV) serotypes 1 and 21 are endemic and transmitted in most years without evidence of disease. However, serotype 16 (BTV-16) infection was detected for the first time in NSW in November 2016 in cattle undergoing testing for export. Retrospective testing of blood samples collected from sentinel cattle as part of the National Arbovirus Monitoring Program (NAMP) established that the first detected transmission of BTV-16 in NSW occurred in April 2016 in sentinel cattle on the NSW North Coast. Subsequently, until 2022, BTV-16 has been transmitted in most years and was the predominant serotype in the 2018-2019 transmission season. The data available suggests that BTV-16 may have become endemic in NSW. EXPERIMENTAL STUDIES: During experimental infection studies with BTV-16, all sheep were febrile, with the peak of viremia occurring 6-10 days after inoculation. There was nasal and oral hyperaemia in most sheep with several animals developing a nasal discharge and nasal oedema. All sheep developed coronitis of varying severity, with most also developing haemorrhages along the coronary band. There was a high incidence of haemorrhage in the pulmonary artery, epicardial petechiae, extensive pericardial haemorrhages and moderate body cavity effusions including pericardial effusions. CONCLUSION: Overall, experimental pathogenicity findings suggest moderate disease may occur in sheep in the field. These findings, when combined with climatic variability that could result in an expansion of the range of Culicoides brevitarsis into major sheep-producing areas of the state, suggest that there is an increasing risk of bluetongue disease in NSW.

Since their discovery in 2014, reptile nidoviruses (also known as serpentoviruses) have emerged as significant pathogens worldwide. They are known for causing severe and often fatal respiratory disease in various captive snake species, especially pythons. Related viruses have been detected in other reptiles with and without respiratory disease, including captive and wild populations of lizards, and wild populations of freshwater turtles. There are many opportunities to better understand the viral diversity, species susceptibility, and clinical presentation in different species in this relatively new field of research. In captive snake collections, reptile nidoviruses can spread quickly and be associated with high morbidity and mortality, yet the potential disease risk to wild reptile populations remains largely unknown, despite reptile species declining on a global scale. Experimental studies or investigations of disease outbreaks in wild reptile populations are scarce, leaving the available literature limited mostly to exploring findings of naturally infected animals in captivity. Further studies into the pathogenesis of different reptile nidoviruses in a variety of reptile species is required to explore the complexity of disease and routes of transmission. This review focuses on the biology of these viruses, hosts and geographic distribution, clinical signs and pathology, laboratory diagnosis and management of reptile nidovirus infections to better understand nidovirus infections in reptiles.

As attention is being focused increasingly towards minimising carbon emissions and enhancing the possibly of material recycling in the construction industry, traditional composite systems are recognised as being problematic on several counts. Composite action between the conventional concrete slab and steel beam is provided typically by stud shear connectors welded to the top flange of the steel beam, and the demolition of such members requires a considerable amount of time and energy, as well as being environmentally intrusive and creating much waste. In addition, existing composite systems mostly utilise conventional concrete made from ordinary Portland cement whose production is attributed to a large portion of carbon emissions worldwide. As an alternative, it is proposed that precast concrete slabs be attached to a steel frame with semi-rigid bolted connections using high-strength friction grip bolts as the elements to provide the shear connection. Moreover, the use of geopolymer concrete in the casting of the slabs eliminates the use of ordinary Portland cement entirely. The paper reports tests undertaken on full-scale beams and on full-scale joints in this sustainable and deconstructable system. This study shows that both the joints and beams demonstrate very significant ductility, with large rotations, deformations and interface slips being developed and sustained during the testing.

Bentonite is one of the most important materials in Plastic concretes due to causes to fill voids of concretes. Plastic concrete is well known as a suitable material for building earth dam cut off due to low permeability, high deformability and enough strength to withstand applied stresses. In this study, we have investigated the effect of the ratio of mixing materials (mixture proportions) and cement as well as the materials' quality such as the type of bentonite on marsh, compressive strength and modulus elasticity of plastic concrete. The results of this study showed that by decreasing the ratio of term activity, compressive strength will be reduced due to increasing free water in case of the stability of other parameters. However, the effect of cement has direct effect on mechanical properties of plastic concrete.

Creosoted timbers are often destroyed in a few years by the marine crustacean wood borer, Limnoria tripunctata. Previous investigators have speculated that the ability of this animal to survive in creosote is afforded by hydrocarbon-metabolizing bacteria present on the wood surface, in the borer tunnels, or in the digestive tracts of the animals. This report evaluates the behavioral responses of two separate populations of L. tripunctata to creosoted wood. The health of the organisms was judged by measuring the production of fecal pellets and by percent survival. A creosote-naive (never exposed to creosote) population of L. tripunctata exhibited 95% survival and produced numerous fecal pellets when exposed to untreated wood. Its survival on wood from an aged creosoted dolphin (dolphin wood) was slightly less, but numerous fecal pellets were produced by Day 2, indicating that this population began boring immediately. This rapid adaptation to the dolphin wood could be attributed to a decrease in the effectiveness of the residual creosote left in the surface layer of the wood. When this wood was sterilized, survival dropped to 80% and fecal pellet production fell below normal; when it was first scraped to expose a new surface, survival declined to 17% on unsterilized wood and 3% on sterilized wood. Fecal pellets were also scarce, indicating the undesirability of this wood to these laboratory-reared animals.