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Aims: To (i) assess the population mortality rates of cocaine‐related deaths in Australia, 2000 to 2021; (ii) determine the circumstances of death and case characteristics; and (iii) determine their toxicological profile. Design: Retrospective study of cocaine‐related deaths in Australia, 2000 to 2021, retrieved from the National Coronial Information System. Setting: Australia‐wide. Cases A total of 884 cases, mean age = 33.8 (SD, 10.0) years and 86.5% (n = 765) male. Measurements Information was collected on characteristics, manner of death and toxicology. Only cases in which the presence of blood cocaine and/or metabolites were included. Findings Population rates did not significantly increase during 2001–2011 (annual percentage change [APC] = 1.5; CI, −3.2, 6.5), but from 2012, there was a marked acceleration (APC = 20.0, 95% CI, 15.5, 25.3). Circumstances of death were unintentional drug toxicity (70.7%, n = 625), intentional self‐harm (17.8%, n = 157), traumatic accident (11.5%, n = 102). The proportion of cases constituted by unintentional toxicity declined across the study period (APC = −2.6; CI, −3.1, −2.1). There was a substantial decline in the proportion of cases with a history of injecting drug use (APC = −5.7; CI, −6.5, −4.9) and with a history of substance use problems (APC = −3.2; CI, −3.9, −2.5). Both cocaine (0.100 vs 0.050 mg/L, P < 0.001) and benzoylecgonine (0.590 vs 0.240 mg/L, P < 0.001) concentrations were higher amongst toxicity cases than in cases of death from traumatic injury. Cocaethylene was present in 26.4% (n = 233), levamisole in 18.6% (n = 164) and lignocaine in 11.5% (n = 102). Psychoactive drugs in addition to cocaine were present in 92.9% (n = 821), most commonly opioids (50.5%, n = 446), alcohol (47.1%, n = 416), hypnosedatives (43.2%, n = 382) and psychostimulants (30.3%, n = 268). There was a steady decline in the proportion of opioid positive cases (APC = −5.4; CI, −6.3, −4.5). Conclusions: There was a large increase in cocaine‐related deaths across Australia from 2000 to 2021. This was accompanied by changes in case profiles, with histories of injecting drug use and substance use problems, as well as recent opioid use, becoming less prominent. [ABSTRACT FROM AUTHOR]

The utility of speleothems as environmental and geological archives has greatly expanded with recent advances in geochronology. Here we reevaluate their ability to constrain late Cenozoic uplift in karst terranes. Using combined U-Th and U-Pb speleothem chronologies for the Buchan karst along the passive margin of southeastern Australia, we calculate a maximum uplift rate of 76 ± 7 m m.y.-1 maintained over the past 3.5 m.y. The timing and extent of this process is consistent with independent constraints on Neogene uplift in Australia, possibly in response to increased plate-boundary strain with New Zealand. Speleothem chronologies provide highly precise age control on individual events and the potential for near-continuous records across long periods of geological time, complementing and expanding upon existing uplift proxies. [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]

The article discusses a 2019 retrospective study on the use of a central venous access device (CVAD) for care of patients with inherited bleeding disorders in Australia. Topics covered include the greater issues suffered by non-infectious complications of CVAD, the higher infectious complication rate, and current inhibitors' increase of infection risk. Also noted is the projected change in CVAD use via extended half-life (EHL) products and non-factor replacement strategies.