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The Australian lungfish, Neoceratodus forsteri (Krefft 1870), is the sole extant member of the Ceratodontidae within the Dipnoi, a small order of sarcopterygian (lobe-finned) fishes, that is thought to be the earliest branching species of extant lungfishes, having changed little over the last 100 million years. To extend studies on anatomical adaptations associated with the fish-tetrapod transition, the ultrastructure of the cornea and iris is investigated using light and electron (transmission and scanning) microscopy to investigate structure-function relationships and compare these to other vertebrate corneas (other fishes and tetrapods). In contrast to previous studies, the cornea is found to have only three main components, comprising an epithelium with its basement membrane, a stroma with a Bowman's layer and an endothelium, and is not split into a dermal (secondary) spectacle and a scleral cornea. The epithelial cells are large, relatively low in density and similar to many species of non-aquatic tetrapods and uniquely possess numerous surface canals that contain and release mucous granules onto the corneal surface to avoid desiccation. A Bowman's layer is present and, in association with extensive branching and anastomosing of the collagen fibrils, may be an adaptation for the inhibition of swelling and/or splitting of the stroma during its amphibious lifestyle. The dorsal region of the stroma possesses aggregations of pigment granules that act as a yellow, short wavelength-absorbing filter during bright light conditions. Desçemet's membrane is absent and replaced by an incomplete basement membrane overlying a monocellular endothelium. The iris is pigmented, well-developed, vascularised and contractile containing reflective crystals anteriorly. Based upon its ultrastructure and functional adaptations, the cornea of N. forsteri is more similar to amphibians than to other bony fishes and is well-adapted for an amphibious lifestyle., (© 2023 The Authors. Journal of Morphology published by Wiley Periodicals LLC.)

Abstract: Background/Objectives: This study documents the perspectives of Australian dermatologists on the adequacy of teaching and training in skin of colour (SOC), and their confidence in diagnosing and treating common medical, surgical and cosmetic issues in SOC and to gauge their desire for further training in this area. Methods: Surveys were distributed to Australasian Dermatologists during their annual scientific meeting in Melbourne, Australia in 2014. Completed surveys from dermatologists nationwide were collected and evaluated. Altogether 270 surveys were distributed. Results: In total, 140 surveys were completed and returned. Four surveys were excluded as they were completed by dermatologists who were not practicing in Australia. Thus, 136 surveys were deemed appropriate for analysis. While 75% of participants were confident in managing common medical issues in SOC 85% were not confident in managing common cosmetic issues in SOC and 75% were not confident performing procedures on SOC. Over 80% stated they would have liked more teaching in SOC during their training and over 50% of those surveyed believe they had enough time to undertake further training in this area. Conclusion: We propose here the first analysis of issues relating to SOC dermatology among Australian dermatologists in the context of the changing patient demographic in the country. The findings of this survey clearly demonstrate there is a need and desire for more training in medical, cosmetic and procedural aspects of SOC dermatology and that most of the Australian dermatologists surveyed have the desire and time to undertake such training. [ABSTRACT FROM AUTHOR]

Abstract: The Canning Stock Route Project (Rock Art and Jukurrpa) has yielded the first radiocarbon dates for rock paintings in the Western Desert of Australia. We report on the results of a large-scale project to directly-date both charcoal and inorganic-pigmented pictographs using plasma oxidation combined with accelerator mass spectrometry. This project has yielded the largest number of art dates from any region in the world: one site alone has produced 12 art dates (from 30 collected samples). Our work advances the testing of the dating method through the systematic use of replicates and explores the methodological implications of dating very small samples (10–40 μg carbon). Thirty-six radiocarbon age determinations range from 3000 years ago to Modern. The results contribute to an understanding of art production in the Australian arid zone during a period of extreme cultural dynamism. We have demonstrated for the first time that significant late Holocene changes in discard rates of artefacts and technological organization of the extractive technologies of implements such seed-grinders is matched by a very high level of stylistic heterogeneity in the art – which has been systematically dated within and between dialect groups. [Copyright &y& Elsevier]

The green alga Botryococcus braunii produces abundant hydrocarbons, in the form of drop-in biodiesel, which promoted interest in the species as a renewable fuel. However, despite the observation of dense populations in the wild, Botryococcus grows very slowly in culture, severely limiting its potential for development as a bioresource. Undertaking a biodiscovery program, we found new strains of Botryococcus in locations ranging from tropical to temperate Australia and from both fresh and brackish waters. As part of the ecophysiological characterisation of this new biodiversity, lipid and pigment compositions were studied for six new strains from six different locations. The strains were inoculated in either freshwater or brackish (salinity of 4)-based medium and maintained over 150 days. The growth of cultures was studied continuously, while lipid and pigment composition were analysed at final harvest on day 150. No significant differences in growth rate between fresh and brackish media were observed. Some strains were more tolerable of brackish conditions than others with a link between salinity tolerance and original location. The use of lower salinity (4 ppt) had a minimal effect on lipid composition, with only two of the six strains showing a different hydrocarbon profile in comparison to the other strains; pigment composition showed only minor variations for fresh and brackish water cultures, although the concentrations varied significantly with the freshwater cultures containing higher pigment concentrations. [ABSTRACT FROM AUTHOR]

Purpose: We compared early age-related macular degeneration (AMD) lesion characteristics between white Australians and Singaporean Asians., Methods: Participants of the Blue Mountains Eye Study (BMES; whites, n = 3508) and the Singapore Epidemiology of Eye Disease Study (SEED; Malay, n = 3280, Indian, n = 3400, and Chinese, n = 3353) underwent examinations, including retinal photography. The AMD lesions were assessed following the Wisconsin AMD grading protocol by the same photographic grader. Prevalence and characteristics of early AMD lesions were compared between the BMES and the SEED. The associations between ethnicity and early AMD lesion types were analyzed using logistic regression models adjusting for age, sex, smoking status, lipids, and genetic polymorphisms associated with AMD., Results: After age-standardization to the BMES population, the prevalence of distinct soft drusen was significantly higher in Singaporeans compared to Australians (23.9%, 95% confidence interval [CI] 22.9-25.0 vs. 6.2%, 95% CI 5.3-7.0), with an adjusted odds ratio (OR) of 4.6 (95% CI 3.4-6.0). In contrast, the prevalence of indistinct soft or reticular drusen was significantly lower in Singaporeans compared to Australians (6.5%, 95% CI 5.9-7.1 vs. 8.3%, 95% CI 7.4-9.3, with nonsignificant adjusted OR of 1.2, 95% CI 0.8-1.7). Soft drusen of any type were present frequently at the inner and outer macula (within a zone ≥500 to <3000 μm radius from the foveal center) among Singaporeans, while among Australians soft drusen were present more frequently at the central macula (<500 μm radius)., Conclusions: Singaporean Asians had a milder spectrum of early AMD lesions and lesion characteristics (predominantly distinct soft drusen and noncentral location) compared to white Australians., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)