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Electrical power sources used in outer planet missions are a key enabling technology for data acquisition and communications. State–of-the-art power sources generate electricity from alpha decay of 238Pu via thermoelectric conversion. However, production of 238Pu requires specialist facilities including a nuclear reactor, a source of 237Np for target irradiation and hotcells to chemically separate neptunium and plutonium within the irradiated targets. These specialist facilities are expensive to build and operate, so naturally, a more economical alternative is attractive to the industry. Within Europe 241Am is considered a promising alternative heat source for radioisotope thermoelectric generators (RTGs) and radioisotope heating units (RHUs). As a daughter product of 241Pu decay, 241Am exists in 1000 kgs quantities within the UK civil plutonium stockpile. A chemical separation process is required to extract the 241Am in a pure form and this paper describes the AMPPEX process (Americium and Plutonium Purification by Extraction), successfully developed over the past five years to isolate 241Am in high yield (> 99%) and to a high purity (> 99%). The process starts by dissolving plutonium dioxide in nitric acid with the aid of a silver(II) catalyst, which is generated electrochemically. The solution is then conditioned and fed to a PUREX type solvent extraction process, where the plutonium is separated from the americium and silver. The plutonium is converted back to plutonium dioxide and the americium is fed forward to a second solvent extraction step. Here the americium is selectively extracted leaving the silver in the aqueous phase. The americium is stripped from the solvent and recovered from solution as americium oxalate, which is calcined to give americium dioxide as the final product. This paper will describe the development of the separation process over a series of six solvent extraction separation trials using centrifugal contactors. The material produced (~ 4g 241Am) was used to make ceramic pellets to establish the behaviour of americium oxide material under high temperature (1450°C) sintering conditions. The chemical separation process is now demonstrated at concentrations expected on the full scale facility taking this process to TRL 4-5.

Summary: Deprivation predicts increased hip fracture risk. Over 14 years, hip fracture incidence increased among men with persisting inequalities. Among women, inequalities in incidence were less pronounced; whilst incidence decreased overall, this improvement was seen marginally less in women from the most deprived areas. Hip fracture prevention programmes have not reduced inequalities. Purpose: Deprivation is associated with increased hip fracture risk. We examined the effect of area-level deprivation on hip fracture incidence in England over 14 years to determine whether inequalities have changed over time. Methods: We used English Hospital Episodes Statistics (2001/2002-2014/2015) to identify hip fractures in adults aged 50+ years and mid-year population estimates (2001-2014) from the Office for National Statistics. The Index of Multiple Deprivation measured local area deprivation. We calculated age-adjusted incidence rate ratios (IRR) for hip fracture, stratified by gender and deprivation quintiles. Results: Over 14 years, we identified 747,369 hospital admissions with an index hip fracture; the number increased from 50,640 in 2001 to 55,092 in 2014; the proportion of men increased from 22.2% to 29.6%. Whereas incidence rates decreased in women (annual reduction 1.1%), they increased in men (annual increase 0.6%) (interaction p < 0.001). Incidence was higher in more deprived areas, particularly among men: IRR most vs. least deprived quintile 1.50 [95% CI 1.48, 1.52] in men, 1.17 [1.16, 1.18] in women. Age-standardised incidence increased for men across all deprivation quintiles from 2001 to 2014. Among women, incidence fell more among those least compared to most deprived (year by deprivation interaction p < 0.001). Conclusions: Deprivation is a stronger relative predictor of hip fracture incidence in men than in women. However, given their higher hip fracture incidence, the absolute burden of deprivation on hip fractures is greater in women. Despite public health efforts to prevent hip fractures, the health inequality gap for hip fracture incidence has not narrowed for men, and marginally widened among women. [ABSTRACT FROM AUTHOR]

Summary: In this study, we report that self-perception of fracture risk captures some aspect of fracture risk not currently measured using conventional fracture prediction tools and is associated with improved medication uptake. It suggests that adequate appreciation of fracture risk may be beneficial and lead to greater healthcare engagement and treatment. Introduction: This study aimed to assess how well self-perception of fracture risk, and fracture risk as estimated by the fracture prediction tool FRAX, related to fracture incidence and uptake and persistence of anti-osteoporosis medication among women participating in the Global Longitudinal study of Osteoporosis in Women (GLOW). Methods: GLOW is an international cohort study involving 723 physician practices across 10 countries in Europe, North America and Australia. Aged ≥ 55 years, 60,393 women completed baseline questionnaires detailing medical history, including co-morbidities, fractures and self-perceived fracture risk (SPR). Annual follow-up included self-reported incident fractures and anti-osteoporosis medication (AOM) use. We calculated FRAX risk without bone mineral density measurement. Results: Of the 39,241 women with at least 1 year of follow-up data, 2132 (5.4%) sustained an incident major osteoporotic fracture over 5 years of follow-up. Within each SPR category, risk of fracture increased as the FRAX categorisation of risk increased. In GLOW, only 11% of women with a lower baseline SPR were taking AOM at baseline, compared with 46% of women with a higher SPR. AOM use tended to increase in the years after a reported fracture. However, women with a lower SPR who were fractured still reported lower AOM rates than women with or without a fracture but had a higher SPR. Conclusions: These results suggest that SPR captures some aspect of fracture risk not currently measured using conventional fracture prediction tools and is also associated with improved medication uptake. [ABSTRACT FROM AUTHOR]