Engineered mineralogical interfaces as radionuclide repositories

Effective capture of fugitive actinides and daughter radionuclides constitutes a major remediation challenge at legacy or nuclear accident sites globally. The ability of double-layered, anionic clay minerals known as hydrotalcites (HTC) to contemporaneously sequester a range of contaminants from solution offers a unique remedy. However, HTC do not provide a robust repository for actinide isolation over the long term. In this study, we formed HTC by in-situ precipitation in a barren lixiviant from a uranium mine and thermally transformed the resulting radionuclide-laden, nanoscale HTC. Atomic-scale forensic examination of the amorphized/recrystallised product reveals segregation of U to nanometre-wide mineral interfaces and the local formation of interface-hosted mineral grains. This U-phase is enriched in rare earth elements, a geochemical analogue of actinides such as Np and Pu, and represents a previously unreported radionuclide interfacial segregation. U-rich phases associated with the mineral interfaces record a U concentration factor of ~ 50,000 relative to the original solute demonstrating high extraction and concentration efficiencies. In addition, the co-existing host mineral suite of periclase, spinel-, and olivine-group minerals that equate to a lower mantle, high P–T mineral assemblage have geochemical and geotechnical properties suitable for disposal in a nuclear waste repository. Our results record the efficient sequestering of radionuclides from contaminated water and this novel, broad-spectrum, nanoscale HTC capture and concentration process constitutes a rapid solute decontamination pathway and solids containment option in perpetuity

An efficient strategy for evaluating new non-invasive screening tests for colorectal cancer: the guiding principles.

New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers. A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles. Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test's ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase III prospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IV studies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence. New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact

Molecular Genetic Contributions to Social Deprivation and Household Income in UK Biobank

SummaryIndividuals with lower socio-economic status (SES) are at increased risk of physical and mental illnesses and tend to die at an earlier age [1–3]. Explanations for the association between SES and health typically focus on factors that are environmental in origin [4]. However, common SNPs have been found collectively to explain around 18% of the phenotypic variance of an area-based social deprivation measure of SES [5]. Molecular genetic studies have also shown that common physical and psychiatric diseases are partly heritable [6]. It is possible that phenotypic associations between SES and health arise partly due to a shared genetic etiology. We conducted a genome-wide association study (GWAS) on social deprivation and on household income using 112,151 participants of UK Biobank. We find that common SNPs explain 21% of the variation in social deprivation and 11% of household income. Two independent loci attained genome-wide significance for household income, with the most significant SNP in each of these loci being rs187848990 on chromosome 2 and rs8100891 on chromosome 19. Genes in the regions of these SNPs have been associated with intellectual disabilities, schizophrenia, and synaptic plasticity. Extensive genetic correlations were found between both measures of SES and illnesses, anthropometric variables, psychiatric disorders, and cognitive ability. These findings suggest that some SNPs associated with SES are involved in the brain and central nervous system. The genetic associations with SES obviously do not reflect direct causal effects and are probably mediated via other partly heritable variables, including cognitive ability, personality, and health

Perceived stimulus complexity and food preference development

The importance of perceived complexity, a 'collative property' as defined by [Berlyne, D. E. (1967). Arousal and reinforcement. In Nebraska symposium on motivation (pp. 1-110). University of Nebraska Press], to the dynamic development of preference was investigated. Eighty-six female and 82 male subjects rated their liking for and various collative properties of seven very similar orange drinks that differed only in perceived complexity as a result of adding small quantities of other flavours. This was done before and after giving each subject extended experience of one of the drinks, each being used equally often for this purpose. As predicted by the theory of [Dember, W. N., & Earl, R. W. (1957). Analysis of exploratory, manipulatory and curiosity behavior. Psychological Review, 64 (2), 91-96] exposure to a stimulus with a slightly higher complexity than an individual subject's optimally preferred level of perceived complexity, caused an upwards shift in that level, whereas exposure to a less complex stimulus had no such effect. Changes in the appreciation of the drinks predicted by the theory were also observed