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Epidemiological trends for major causes of death and disability, such as stroke, may be monitored using administrative data to guide public health initiatives and service delivery. We calculated admissions rates for ischaemic stroke, intracerebral haemorrhage and subarachnoid haemorrhage between 1 January 2005 and December 31st, 2013 and rates of 30-day mortality and 365-day mortality in 30-day survivors to 31 December 2014 for patients aged 15 years or older from New South Wales, Australia. Annual Average Percentage Change in rates was estimated using negative binomial regression. Of 81,703 eligible admissions, 64,047 (78.4%) were ischaemic strokes and 13,302 (16.3%) and 4,778 (5.8%) were intracerebral and subarachnoid haemorrhages, respectively. Intracerebral haemorrhage admissions significantly declined by an average of 2.2% annually (95% Confidence Interval = −3.5% to −0.9%) (p < 0.001). Thirty-day mortality rates significantly declined for ischaemic stroke (Average Percentage Change −2.9%, 95% Confidence Interval = −5.2% to −1.0%) (p = 0.004) and subarachnoid haemorrhage (Average Percentage Change = −2.6%, 95% Confidence Interval = −4.8% to −0.2%) (p = 0.04). Mortality at 365-days amongst 30-day survivors of ischaemic stroke and intracerebral haemorrhage was stable over time and increased in subarachnoid haemorrhage (Annual Percentage Change 6.2%, 95% Confidence Interval = −0.1% to 12.8%), although not significantly (p = 0.05). Improved prevention may have underpinned declining intracerebral haemorrhage rates while survival gains suggest that innovations in care are being successfully translated. Mortality in patients surviving the acute period is unchanged and may be increasing for subarachnoid haemorrhage warranting investment in post-discharge care and secondary prevention. [ABSTRACT FROM AUTHOR]

Higher stocking rates of lambing ewes have been associated with poorer ewe-lamb behaviour and lamb survival. This study tested the hypothesis that increasing the mob size and stocking rate of lambing ewes on commercial farms will reduce the survival of their lambs. Data were collected from 66 producers in Australia for Experiment one and 22 producers in New Zealand for Experiment two. Survival of single- and twin-born lambs decreased by 1.4% and 3.5% per extra 100 ewes in the mob, regardless of breed, in Experiment one. The survival of Merino lambs in Experiment two decreased by 0.9% per extra 100 ewes in the mob, regardless of birth type. Increasing stocking rate by 1 ewe/ha also decreased lamb survival by 0.7% in Experiment one. However, this was not evident in Experiment two. These findings highlight the scope to optimise ewe mob size and stocking rate at lambing to improve lamb survival. [ABSTRACT FROM AUTHOR]

Much of our current understanding of song originates from studies of species living in seasonal environments, where breeding seasons are short and highly synchronised at the population level. By comparison, the form and function of song are less well understood in aseasonal environments, where breeding cycles are less predictable. We examined song rates of male and female Chirruping Wedgebills (Psophodes cristatus), a passerine endemic to the arid regions of inland, south-eastern Australia, across a 4 month period of breeding activity. Our results show that both males and females sing, and provide evidence of duetting. The song rate of male Wedgebills was highest in the early morning and during breeding and was substantially higher than the song rate of female Wedgebills. Over the course of the day, bouts of male singing were two orders of magnitude longer than females. By contrast, female song rate was independent of the time of day or reproductive phase. Females more often sang in tandem with their partners than expected by chance and duets occurred at a relatively low rate, independently of breeding phase. We discuss the possibility that male and female song and duets serve different functions. [ABSTRACT FROM AUTHOR]

We study the influence of a mortality trade-off in a nonlocal reaction-diffusion-mutation equation that we introduce to model the invasion of cane toads in Australia. This model is built off of one that has attracted attention recently, in which the population of toads is structured by a phenotypical trait that governs the spatial diffusion. We are concerned with the case when the diffusivity can take unbounded values and the mortality trade-off depends only on the trait variable. Depending on the rate of increase of the penalization term, we obtain the rate of spreading of the population. We identify two regimes, an acceleration regime when the penalization is weak and a linear spreading regime when the penalization is strong. While the development of the model comes from biological principles, the bulk of the article is dedicated to the mathematical analysis of the model, which is very technical. The upper and lower bounds are proved via the Li-Yau estimates of the fundamental solution of the heat equation with potential on Riemannian manifolds and a moving ball technique, respectively, and the traveling waves by a Leray-Schauder fixed point argument. We also present a simple method for a priori bounds. [ABSTRACT FROM AUTHOR]