e+e−e^{+}e^{-} pairs from a nuclear transition signaling an elusive light neutral boson

Electron-positron pairs have been observed in the 10.95-MeV $0^-\to0^+$ decay in $^{16}$O. The branching ratio of the e$^+$e$^-$ pairs compared to the 3.84-MeV $0^-\to2^+$ $\gamma$ decay of the level is deduced to be $20(5)\times10^{-5}$. This magnetic monopole (M0) transition cannot proceed by $\gamma$-ray decay and is, to first order, forbidden for internal pair creation. However, the transition may also proceed by the emission of a light neutral $0^{-}$ or $1^{+}$ boson. Indeed, we do observe a sharp peak in the $e^{+}e^{-}$ angular correlation with all the characteristics belonging to the intermediate emission of such a boson with an invariant mass of 8.5(5) MeV/c$^2$. It may play a role in the current quest for light dark matter in the universe.Comment: 6 page

Prioritisation of weed species relevant to Australian livestock industries for biological control

Classical biological control is the only realistic option for managing many of the most serious weeds affecting livestock industries in Australia. This project developed and applied a framework, based on a matrix assessment system, to prioritise biocontrol efforts using new agents against 79 weed taxa. These taxa were identified in a concurrent project as priorities for Research, Development and Extension to address weed problems of Australian livestock industries. The framework considered the current and potential impacts of the weeds versus prospects for biocontrol. The latter combined assessments of feasibility of undertaking a biocontrol program that would yield host-specific agents, and the likelihood that agents would be successful in mitigating the impacts of the weeds once released in Australia. Each categorisation was supported with a written rationale that explained the ranking assigned and captured uncertainties. Key investment areas for future actions to address biocontrol knowledge gaps for each weed were identified. Twenty-one weeds with the highest combined rankings for biocontrol prospects and current and/or potential impacts were shortlisted as priority taxa for future investment. Results provide the best available information for funding agencies responsible for RD&E for livestock industries to make investment decisions across their weed biocontrol portfolio

Pentecostal intimacies: women and intimate citizenship in the ministry of repentance and holiness in Kenya

This article explores the intersections of gender, sexuality and citizenship in the context of one prominent neo-Pentecostal movement in Kenya, the Ministry of Repentance and Holiness (MRH) led by the charismatic Prophet David Owuor. Employing the concept of intimate citizenship, the article analyses, first, how MRH engages in a contestation of intimate citizenship in the contemporary Kenyan public sphere, especially in relation to women’s bodies. Second, it examines how MRH simultaneously configures, through a range of highly intimate beliefs, practices and techniques, an alternative form of intimate citizenship defined by moral purity and concerned with a political project of moral regeneration. Coining the notion of ‘Pentecostal intimacies’, the article provides insight into the reasons why so many people, especially women, are attracted to MRH, and hence it interrogates the liberal frame in which intimate citizenship is usually conceptualised

Phenotypic Divergence During the Invasion of \u3cem\u3ePhyla Canescens\u3c/em\u3e in Australia and France: Evidence for Selection-Driven Evolution

Rapid adaptive evolution has been advocated as a mechanism that promotes invasion. Demonstrating adaptive evolution in invasive species requires rigorous analysis of phenotypic shifts driven by selection. Here, we document selection-driven evolution of Phyla canescens, an Argentine weed, in two invaded regions (Australia and France). Invasive populations possessed similar or higher diversity than native populations, and displayed mixed lineages from different sources, suggesting that genetic bottlenecks in both countries might have been alleviated by multiple introductions. Compared to native populations, Australian populations displayed more investment in sexual reproduction, whereas French populations possessed enhanced vegetative reproduction and growth. We partitioned evolutionary forces (selection vs. stochastic events) using two independent methods. Results of both analyses suggest that the pattern of molecular and phenotypic variability among regions was consistent with selection-driven evolution, rather than stochastic events. Our findings indicate that selection has shaped the evolution of P. canescens in two different invaded regions

A multi-detector array for high energy nuclear e+e- pair spectrosocopy

A multi-detector array has been constructed for the simultaneous measurement of energy- and angular correlation of electron-positron pairs produced in internal pair conversion (IPC) of nuclear transitions up to 18 MeV. The response functions of the individual detectors have been measured with mono-energetic beams of electrons. Experimental results obtained with 1.6 MeV protons on targets containing $^{11}$B and $^{19}$F show clear IPC over a wide angular range. A comparison with GEANT simulations demonstrates that angular correlations of $e^+e^-$ pairs of transitions in the energy range between 6 and 18 MeV can be determined with sufficient resolution and efficiency to search for deviations from IPC due to the creation and subsequent decay into $e^+e^-$ of a hypothetical short-lived neutral boson.Comment: 20 pages, 8 figure

Isotopic analysis of faunal material from South Uist, Western Isles, Scotland

This paper reports on the results from stable isotope analysis of faunal bone collagen from a number of Iron Age and later sites on the island of South Uist, in the Western Isles, Scotland. This preliminary investigation into the isotopic signatures of the fauna is part of a larger project to model the interaction between humans, animals, and the broader environment in the Western Isles. The results demonstrate that the island fauna data fall within the range of expected results for the UK, with the terrestrial herbivorous diets of cattle and sheep confi rmed. The isotopic composition for pigs suggests that some of these animals had an omnivorous diet, whilst a single red deer value might be suggestive of the consumption of marine foods, such as by grazing on seaweed. However, further analysis is needed in order to verify this anomalous isotopic ratio