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Few rocks or minerals display a blue hue; this is especially true for natural glasses. As glasses are already uncommon compared to crystalline rocks due to their instability, the rarity of blue glass makes a fulgurite found in Marquette Michigan worthy of further examination. We study the morphology and the chemical and structural characteristics of the blue fulgurite using Raman spectroscopy, X-Ray Fluorescence analysis, Election Microprobe Analysis, and Transmission Election Microscopy. We use the experimental results to compare the fulgurite with another blue natural glass, zhanmanshinite, an impact glass named after an exposed impact crater in Kazakhstan, and to evaluate the support for several hypotheses of the origin of the blue color in the fulgurite.

Planetary habitability is in part governed by nutrient availability, including the availability of the element phosphorus. The nutrient phosphorus plays roles in various necessary biochemical functions, and its biogeochemical cycling has been proposed to be extremely slow due to a strong coupling to the rock cycle via mineral weathering. Here we show a route to P liberation from water-rock reactions that are thought to be common throughout the Solar System. We report the speciation of phosphorus in serpentinite rocks to include the ion phosphite (HPO32- with P3+) and show that reduction of phosphate to phosphite is predicted from thermodynamic models of serpentinization. As a result, as olivine in ultramafic rocks alters to serpentine minerals, phosphorus as soluble phosphite should be released under low redox conditions, liberating this key nutrient for life. Thus, this element may be accessible to developing life where water is in direct contact with ultramafic rock, providing a source of this nutrient to potentially habitable worlds.

usc Introduction: We conducted a detailed analysis of trends in new HIV diagnoses in Australia by country of birth, to understand any changes in epidemiology, relationship to migration patterns and implications for public health programs. Methods: Poisson regression analyses were performed, comparing the age-standardised HIV diagnosis rates per 100,000 estimated resident population between 2006–2010 and 2011–2015 by region of birth, with stratification by exposure (male-to-male sex, heterosexual sex–males and females). Correlation between the number of permanent and long-term arrivals was also explored using linear regression models. Results: Between 2006 and 2015, there were 6,741 new HIV diagnoses attributed to male-to-male sex and 2,093 attributed to heterosexual sex, with the proportion of diagnoses attributed to male-to-male sex who were Australian-born decreasing from 72.5% to 66.5%. Compared with 2006–2010, the average annual HIV diagnosis rate per 100,000 in 2011–15 attributed to male-to-male sex was significantly higher in men born in South-East Asia (summary rate ratio (SRR) = 1.37, p = 0.001), North-East Asia (SRR = 2.18, p

The Nambour Skin Cancer and Actinic Eye Disease Prevention Trial (the Nambour Trial) is a field trial conducted in an unselected adult population in Australia. Using a randomized 2 x 2 factorial design, the principal aim is to evaluate whether regular use of high-protection sunscreen and/or dietary supplementation with beta-carotene (30 mg daily) can alter the incidence rates of basal cell carcinomas and squamous cell carcinomas of the skin over a minimum follow-up time of 4.5 years. Changes in the incidence of solar keratoses and actinic eye disease and the rate of photoaging after intervention will also be investigated. In 1992, 1626 participants between the ages of 25 and 75 years were enrolled, all of whom had been randomly selected from residents of the southeastern Queensland township of Nambour for an earlier skin cancer prevalence survey. This paper describes the background to the trial and its design, with respect to evaluation of effects on actinic skin disease, and documents the baseline characteristics of participants recruited into the Nambour Trial.

Background An increase in the notification rate of gonorrhoea was observed in the national surveillance system. In Australia, gonorrhoea is relatively rare, apart from among some populations of Aboriginal people and men who have sex with men. Methods: Data about gonorrhoea cases reported between 2007 and 2012 from all Australian jurisdictions were extracted from the National Notifiable Diseases Surveillance System. Analyses were undertaken of the time trends in counts and rates, according to jurisdiction, gender, Aboriginal and Torres Strait Islander status, diagnosis method and sexual orientation. Results: The largest increase in notifications between 2007 and 2012 was observed in both men and women in New South Wales (2.9- and 3.7-fold greater in 2012 than 2007, respectively) and Victoria (2.4- and 2.7-fold greater in 2012 than 2007, respectively), men in the Australian Capital Territory and women in Queensland. The highest notification rates remained in Indigenous people in the Northern Territory and Western Australia, and particularly in women, although rates may have decreased over the study period. Changes in age and sex distribution, antimicrobial resistance and patterns of exposure and acquisition were negligible. Conclusions: There is an ongoing gonorrhoea epidemic affecting Aboriginal and Torres Strait Islander people in Australia, but the increases in notifications have occurred primarily in non-Aboriginal populations in the larger jurisdictions. Interpretation of these surveillance data, especially in relation to changes in population subgroups, would be enhanced by laboratory testing data. Further efforts are needed to decrease infection rates in populations at highest risk.

Summary Background The use of sunscreens on the skin can prevent sunburn but whether long-term use can prevent skin cancer is not known. Also, there is evidence that oral betacarotene supplementation lowers skin-cancer rates in animals, but there is limited evidence of its effect in human beings. Methods In a community-based randomised trial with a 2 by 2 factorial design, individuals were assigned to four treatment groups: daily application of a sun protection factor 15-plus sunscreen to the head, neck, arms, and hands, and betacarotene supplementation (30 mg per day); sunscreen plus placebo tablets; betacarotene only; or placebo only. Participants were 1621 residents of Nambour in southeast Queensland, Australia. The endpoints after 4·5 years of follow-up were the incidence of basal-cell and squamous-cell carcinomas both in terms of people treated for newly diagnosed disease and in terms of the numbers of tumours that occurred. Analysis of the effect of sunscreen was based only on skin cancers that developed on sites of daily application. All analyses were by intention to treat. Findings 1383 participants underwent full skin examination by a dermatologist in the follow-up period. 250 of them developed 758 new skin cancers during the follow-up period. There were no significant differences in the incidence of first new skin cancers between groups randomly assigned daily sunscreen and no daily sunscreen (basal-cell carcinoma 2588 vs 2509 per 100 000; rate ratio 1·03 [95% CI 0·73–1·46]; squamous-cell carcinoma 876 vs 996 per 100 000; rate ratio 0·88 [0·50–1·56]). Similarly, there was no significant difference between the betacarotene and placebo groups in incidence of either cancer (basal-cell carcinoma 3954 vs 3806 per 100 000; 1·04 [0·73–1·27]; squamous-cell carcinoma 1508 vs 1146 per 100 000; 1·35 [0·84–2·19]). In terms of the number of tumours, there was no effect on incidence of basal-cell carcinoma by sunscreen use or by betacarotene but the incidence of squamous-cell carcinoma was significantly lower in the sunscreen group than in the no daily sunscreen group (1115 vs 1832 per 100 000; 0·61 [0·46–0·81]). Interpretation There was no harmful effect of daily use of sunscreen in this medium-term study. Cutaneous squamous-cell carcinoma, but not basal-cell carcinoma seems to be amenable to prevention through the routine use of sunscreen by adults for 4·5 years. There was no beneficial or harmful effect on the rates of either type of skin cancer, as a result of betacarotene supplementation.