Atomic Beam Research

Contains research objectives and reports on five research projects

Nuclear Magnetic Resonance and Hyperfine Structure

Contains reports on four research projects

Hurricane impacts on the Caribbean coastal/marine environment : using scientific assessment to plan for the future

The passage of Hurricane Hugo through the eastern Caribbean provided a unique opportunity for multidisciplinary study of (1) the effects of severe storms on tropical coastal and marine ecosystems, and (2) the physical and biological responses of those ecosystems to intense storm-induced changes. In addition to its direct value as basic science, this study can be used to facilitate development of improved coastal and marine resource management capabilities.Funding was provided by the Andrew W. Mellon Foundation to the Coastal Research Center of the Woods Hole Oceanographic Institution (WHOI) and the NOAA National Sea Grant College Program Offce, Department of Commerce, under Grant No. NA86-AA-D-90

Containing COVID: the establishment and management of a COVID-19 ward in an adult psychiatric hospital

BACKGROUND: As the coronavirus disease 2019 (COVID-19) epidemic in the UK emerged and escalated, clinicians working in mental health in-patient facilities faced unique medical, psychiatric and staffing challenges in managing and containing the impact of the virus and, in the context of legislation, enforcing social distancing. AIMS: To describe (a) the steps taken by one mental health hospital to establish a COVID-19 isolation ward for adult psychiatric in-patients and (b) how staff addressed the challenges that emerged over the period March to June 2020. METHOD: A descriptive study detailing the processes involved in changing the role of the ward and the measures taken to address the various challenges that arose. Brief clinical cases of two patients are included for illustrative purposes. RESULTS: We describe the achievements, lessons learned and outcomes of the process of repurposing a mental health triage ward into a COVID-19 isolation facility, including the impact on staff. Flexibility, rapid problem-solving and close teamwork were essential. Some of the changes made will be sustained on the ward in our primary role as a triage ward. CONCLUSIONS: Although the challenges faced were difficult, the legacy they have left is that of a range of improvements in patient care and the working environment

Study of Video Assisted BSS for Convolutive Mixtures

In this paper we present an overview of recent research in the area of audio-visual blind source separation (BSS), together with new results of our work that highlight the advantage of including visual information into a BSS algorithm. In our work the visual information is combined with audio information to form joint audio-visual feature vectors. The audio-visual coherence is then modelled using statistical models. The outputs of these models are used within a frequency domain BSS algorithm to control the step size. Experimental results verify the improvement of the audio-visual method compared to audio only BSS. We also discuss visual feature extraction techniques, along with several recently published methods for audio-visual BSS, and conclude with suggestions for future research

The Slottsmøya marine reptile Lagerstätte: depositional environments, taphonomy and diagenesis

The Late Jurassic Slottsmøya Member Lagerstätte on Spitsbergen offers a unique opportunity to study the relationships between vertebrate fossil preservation, invertebrate occurrences and depositional environment. In this study, 21 plesiosaurian and 17 ichthyosaur specimens are described with respect to articulation, landing mode, preservation, and possible predation and scavenging. The stratigraphic distribution of marine reptiles in the Slottsmøya Member is analysed, and a correlation between high total organic content, low oxygen levels, few benthic invertebrates and optimal reptile preservation is observed. A new model for 3D preservation of vertebrates in highly compacted organic shales is explained

A copper isotope investigation of methane cycling in Late Archaean sediments

This research was supported by NERC award NE/L002590/1 to the IAPETUS DTP, and by NERC Standard Grant NE/J023485/2 to A.L.Z. The initiation of Cu isotope analysis at the University of St Andrews was aided significantly by a Carnegie Trust Research Incentive Grant awarded to P.S.S.The rise of oxygenic photosynthesis arguably represents the most important evolutionary step in Earth history. Recent studies, however, suggest that Earth’s pre-oxidative atmosphere was also heavily influenced by biological feedbacks. Most notably, recent geochemical records propose the existence of a hydrocarbon haze which periodically formed in response to enhanced biospheric methane fluxes. Copper isotopes provide a potential proxy for biological methane cycling; Cu is a bioessential trace metal and a key element in the aerobic oxidation of methane to carbon dioxide (methanotrophy). In addition, Cu isotopes are fractionated during biological uptake. Here, we present a high-resolution Cu isotope record measured in a suite of shales and carbonates from core GKF01, through the ~2.6–2.5 Ga Campbellrand-Malmani carbonate platform. Our data show a 0.85‰ range in Cu isotope composition and a negative excursion that predates the onset of a haze event. We interpret this excursion as representing a period of enhanced aerobic methane oxidation before the onset of the Great Oxidation Event. This places valuable time constraints on the evolution of this metabolism and firmly establishing Cu isotopes as a biomarker in Late Archaean rocks.PostprintPeer reviewe

Sulfur isotopes of hydrothermal vent fossils and insights into microbial sulfur cycling within a lower Paleozoic (Ordovician‐early Silurian) vent community

This study was supported by a UK Natural Environment Research Council grant (NERC; number NE/R000670/1 to AG). MG is also grateful for support from an Ifremer Postdoctoral Fellowship. Alvinella samples were collected with the help of a NERC Small Grant (number NE/C000714/1 to CTSL). S isotopic analyses were undertaken under NERC Facility awards IP-1755-1117 and IMF672/1118.Symbioses between metazoans and microbes involved in sulfur cycling are integral to the ability of animals to thrive within deep‐sea hydrothermal vent environments; the development of such interactions is regarded as a key adaptation in enabling animals to successfully colonize vents. Microbes often colonize the surfaces of vent animals and, remarkably, these associations can also be observed intricately preserved by pyrite in the fossil record of vent environments, stretching back to the lower Paleozoic (Ordovician‐early Silurian). In non‐vent environments, sulfur isotopes are often employed to investigate the metabolic strategies of both modern and fossil organisms, as certain metabolic pathways of microbes, notably sulfate reduction, can produce large sulfur isotope fractionations. However, the sulfur isotopes of vent fossils, both ancient and recently mineralized, have seldom been explored, and it is not known if the pyrite‐preserved vent organisms might also preserve potential signatures of their metabolisms. Here, we use high‐resolution secondary ion mass spectrometry (SIMS) to investigate the sulfur isotopes of pyrites from recently mineralized and Ordovician‐early Silurian tubeworm fossils with associated microbial fossils. Our results demonstrate that pyrites containing microbial fossils consistently have significantly more negative δ34S values compared with nearby non‐fossiliferous pyrites, and thus represent the first indication that the presence of microbial sulfur‐cycling communities active at the time of pyrite formation influenced the sulfur isotope signatures of pyrite at hydrothermal vents. The observed depletions in δ34S are generally small in magnitude and are perhaps best explained by sulfur isotope fractionation through a combination of sulfur‐cycling processes carried out by vent microbes. These results highlight the potential for using sulfur isotopes to explore biological functional relationships within fossil vent communities, and to enhance understanding of how microbial and animal life has co‐evolved to colonize vents throughout geological time.Publisher PDFPeer reviewe

Nuclear Magnetic Resonance and Hyperfine Structure

Contains reports on two research projects