On using a pyroclastic deposit as a manned lunar base site

Hawke et al. (1990) suggest that ilmenite found in Apollo 17-type pyroclastic glass may provide feedstock for the hydrogen reduction of ilmenite process for producing lunar oxygen. They also suggest that the ilmenite may help retain solar wind hydrogen and helium which can be extracted for use at a lunar outpost or even transported back to Earth for fusion fuel in the case of helium-3. Therefore, they suggest that ilmenite-rich material may be the best candidate. Here, researchers propose a somewhat different approach. They propose that the pyroclastic glass can be reduced directly to produce oxygen and one or more metals. Sulfur would be another important byproduct of the processing. This process would eliminate the need for having specific minerals such as ilmenite or for doing any mineral concentration. The bulk pyroclastic would provide the feedstock. Some recent experiments at the Johnson Space Center suggest that an iron-rich composition would be the most suitable for this direct feedstock reduction and that the titanium content may not be important. Also, the lunar pyroclastic deposits would be extremely useful in constructing and supporting a lunar base

Estimating Lunar Pyroclastic Deposit Depth from Imaging Radar Data: Applications to Lunar Resource Assessment

Lunar pyroclastic deposits represent one of the primary anticipated sources of raw materials for future human settlements. These deposits are fine-grained volcanic debris layers produced by explosive volcanism contemporaneous with the early stage of mare infilling. There are several large regional pyroclastic units on the Moon (for example, the Aristarchus Plateau, Rima Bode, and Sulpicius Gallus formations), and numerous localized examples, which often occur as dark-halo deposits around endogenic craters (such as in the floor of Alphonsus Crater). Several regional pyroclastic deposits were studied with spectral reflectance techniques: the Aristarchus Plateau materials were found to be a relatively homogeneous blanket of iron-rich glasses. One such deposit was sampled at the Apollo 17 landing site, and was found to have ferrous oxide and titanium dioxide contents of 12 percent and 5 percent, respectively. While the areal extent of these deposits is relatively well defined from orbital photographs, their depths have been constrained only by a few studies of partially filled impact craters and by imaging radar data. A model for radar backscatter from mantled units applicable to both 70-cm and 12.6-cm wavelength radar data is presented. Depth estimates from such radar observations may be useful in planning future utilization of lunar pyroclastic deposits

Dynamics and Gravitational Wave Signature of Collapsar Formation

We perform 3+1 general relativistic simulations of rotating core collapse in the context of the collapsar model for long gamma-ray bursts. We employ a realistic progenitor, rotation based on results of stellar evolution calculations, and a simplified equation of state. Our simulations track self-consistently collapse, bounce, the postbounce phase, black hole formation, and the subsequent early hyperaccretion phase. We extract gravitational waves from the spacetime curvature and identify a unique gravitational wave signature associated with the early phase of collapsar formation

The effects of estradiol on mood and behavior in human female adolescents: a systematic review

Mood disorders and health risk behaviors increase in adolescence. Puberty is considered to contribute to these events. However, the precise impact of pubertal hormone changes to the emergence of mood disorders and risk behaviors is relatively unclear. It is important that inappropriate attribution is not made. Our aim was to determine what is known about the effect of endogenous estradiol on human adolescent girls’ mood and behavior. The databases searched were MEDLINE, Embase, PsycINFO, Education Resources Information Center (ERIC), Pre-MEDLINE, Web of Science, and Scopus for all dates to October 2014. For inclusion, contemporaneous hormone and mood or behavioral assessment was required. Data were extracted following a template created by the authors. Fourteen studies met our inclusion criteria. There was some consistency in findings for mood and estradiol levels, with associations between estradiol and depression and emotional tone and risk taking. Results were less consistent for studies assessing other mood and behavioural outcomes. Most studies were cross-sectional in design; assay methodologies used in older studies may lack the precision to detect early pubertal hormone levels. Conclusion: Three longitudinal and several cross-sectional studies indicate potential associations between estradiol and certain mood or affective states, especially depression and mood variability though there are insufficient data to confirm that the rise in estradiol during puberty is causative. We believe that it is important for health professionals to take care when attributing adolescent psychopathology to puberty hormones, as the current data supporting these assertions are limited.Australian National Health and Medical Research Council (NHMRC

Calculating the mass fraction of primordial black holes

We reinspect the calculation for the mass fraction of primordial black holes (PBHs) which are formed from primordial perturbations, finding that performing the calculation using the comoving curvature perturbation c in the standard way vastly overestimates the number of PBHs, by many orders of magnitude. This is because PBHs form shortly after horizon entry, meaning modes significantly larger than the PBH are unobservable and should not affect whether a PBH forms or not - this important effect is not taken into account by smoothing the distribution in the standard fashion. We discuss alternative methods and argue that the density contrast, Δ, should be used instead as super-horizon modes are damped by a factor k2. We make a comparison between using a Press-Schechter approach and peaks theory, finding that the two are in close agreement in the region of interest. We also investigate the effect of varying the spectral index, and the running of the spectral index, on the abundance of primordial black holes

Foot health of Aboriginal and Torres Strait Islander Peoples in regional and rural NSW, Australia

Background: Foot health of Aboriginal and Torres Strait Islander Australians' has not been established. Additionally, studies have shown that there is a lack of engagement of this population with general preventive foot care services. The aim of this study was to establish foot health in Aboriginal and Torres Strait Islander people attending two recently developed, culturally safe podiatry services in rural and regional New South Wales (NSW), Australia. Secondarily the relationship between self-perceived foot health and some medical and demographic characteristics was investigated. Methods: This descriptive cross-sectional study included participants attending the culturally safe foot health care services managed by the University of Newcastle on the Central Coast or in Wellington, both located in NSW, Australia. At the consultation, participants completed the Foot Health Status Questionnaire (FHSQ) with the assistance of an Aboriginal health care worker, underwent basic vascular and neurological screening, and podiatric treatment. Results: A total of 111 Aboriginal and Torres Strait Islander Australians (48 from the Central Coast, and 63 from Wellington) were included. FHSQ scores for pain (75.7 ± 26.8), function (80.2 ± 25.2), footwear (53.9 ± 33.4), and general foot health (62.0 ± 30.9) were generally good, but below the optimal score of 100. The presence of diabetes (n = 39 of 111 participants or 35.1%) was associated with lower levels of self-perceived foot function (r = - 0.20, n = 107, p = 0.04). Conclusion: We found that community-based foot health care services that are culturally safe are utilised by Aboriginal and Torres Strait Islander Peoples not currently at high risk of foot complications. This supports the use of culturally safe foot care services to improve engagement with preventative foot care. Future research should continue to be driven by Aboriginal and Torres Strait Islander Peoples and investigate ways to implement additional screening measures and undertake prospective evaluation of the impact of such services on health related outcomes in these communities. © 2020 The Author(s)

Impact Melt in Small Lunar Highlands Craters

Impact-melt deposits are a typical characteristic of complex impact craters, occurring as thick pools on the crater floor, ponds on wall terraces, veneers on the walls, and flows outside and inside the rim. Studies of the distribution of impact melt suggested that such deposits are rare to absent in and around small (km to sub-km), simple impact craters. noted that the smallest lunar crater observed with impact melt was approximately 750 m in diameter. Similarly, theoretical models suggest that the amount of melt formed is a tiny fraction (<1%) of the total crater volume and thus significant deposits would not be expected for small lunar craters. LRO LROC images show that impact-melt deposits can be recognized associated with many simple craters to diameters down to approximately 200 m. The melt forms pools on the crater floor, veneer on the crater walls or ejecta outside the crater. Such melt deposits are relatively rare, and can be recognized only in some fresh craters. These observations indicate that identifiable quantities of impact melt can be produced in small impacts and the presence of such deposits shows that the material can be aggregated into recognizable deposits. Further, the present of such melt indicates that small craters could be reliably radiometrically dated helping to constrain the recent impact flux

Signatures of non-gaussianity in the isocurvature modes of primordial black hole dark matter

Primordial black holes (PBHs) are black holes which may have formed very early on during the radiation dominated era in the early universe. We present here a method by which the large scale perturbations in the density of primordial black holes may be used to place tight constraints on non-gaussianity if PBHs account for dark matter (DM). The presence of local-type non-gaussianity is known to have a significant effect on the abundance of primordial black holes, and modal coupling from the observed CMB scale modes can significantly alter the number density of PBHs that form within different regions of the universe, which appear as DM isocurvature modes. Using the recent \emph{Planck} constraints on isocurvature perturbations, we show that PBHs are excluded as DM candidates for even very small local-type non-gaussianity, $|f_{NL}|\approx0.001$ and remarkably the constraint on $g_{NL}$ is almost as strong. Even small non-gaussianity is excluded if DM is composed of PBHs. If local non-Gaussianity is ever detected on CMB scales, the constraints on the fraction of the universe collapsing into PBHs (which are massive enough to have not yet evaporated) will become much tighter.Comment: 23 pages, 11 figures. V2: minor corrections and changes, matches published versio

Release of the national scheme's Aboriginal and Torres Strait Islander health and cultural safety strategy 2020-2025; the impacts for podiatry in Australia : a commentary

Background Developing since colonisation, Australia's healthcare system has dismissed an ongoing and successful First Nations health paradigm in place for 60,000 years. From Captain James Cook documenting 'very old' First Nations Peoples being 'far more happier than we Europeans' and Governor Arthur Phillip naming Manly in admiration of the physical health of Gadigal men of the Eora Nation, to anthropologist Daisy Bates' observation of First Nations Peoples living 'into their eighties' and having a higher life expectancy than Europeans; our healthcare system's shameful cultural safety deficit has allowed for an Aboriginal and Torres Strait Islander child born in Australia today to expect to live 9 years less than a non-Indigenous child. Disproportionately negative healthcare outcomes including early onset diabetes-related foot disease and high rates of lower limb amputation in Aboriginal and Torres Strait Islander Peoples contribute to this gross inequity. Main body In 2020, the Australian Health Practitioner Regulation Authority released the National Scheme's Aboriginal and Torres Strait Islander Health and Cultural Safety Strategy 2020-2025 - empowering all registered health practitioners within Australia to provide health care to Aboriginal and Torres Strait Islander Peoples that is inclusive, respectful and safe, as judged by the recipient of care. This recently released strategy is critically important to the podiatry profession in Australia. As clinicians, researchers and educators we have a collective responsibility to engage with this strategy of cultural safety. This commentary defines cultural safety for podiatry and outlines the components of the strategy in the context of our profession. Discussion considers the impact of the strategy on podiatry. It identifies mechanisms for podiatrists in all settings to facilitate safer practice, thereby advancing healthcare to produce more equitable outcomes. Conclusion Aboriginal and Torres Strait Islander Peoples access health services more frequently and have better health outcomes where provision of care is culturally safe. By engaging with the National Scheme's Aboriginal and Torres Strait Islander Health and Cultural Safety Strategy, all registered podiatrists in Australia can contribute to achieving equity in health outcomes for Aboriginal and Torres Strait Islander Peoples