Stimulating exploration by government-sponsored regional geoscience surveys

The island of Ireland is one of the most attractive places for mineral exploration and development, according to a recent global review. The Republic of Ireland is a major European producer of lead-zinc and historically of copper, lead-silver and alluvial gold. Northern Ireland has one gold mine in production, a second gold prospect at an advanced stage of exploration, and one salt mine. In the past lead, iron and coal mining have all been prominent. Other minerals that are or have in the past been mined in the island include bauxite, barite, gypsum, coal and high-grade aggregates. In Northern Ireland, prospecting in recent years has been stimulated by the Tellus Project, managed by the Geological Survey of Northern Ireland. Between 2004 and 2007 this government-funded initiative completed soil and stream geochemical samples surveys and a low-level airborne geophysical survey of Northern Ireland, an area of 13,800 km2. Within 12 months of the data launch in 2007 the area of Northern Ireland licensed for exploration increased from 15% to 70% and the subsequent private sector investment in exploration now exceeds £32 million. Targets include gold, platinum group elements and base metals. The project is a good example of how regional geo-science surveys can stimulate exploration activity and inward investment. Historically the principal focus of prospecting in Northern Ireland has been the area of vein gold deposits in Neoproterozoic rocks of County Tyrone, centred on the deposits at Curraghinalt and Cavanacaw. Here, the airborne magnetic and electromagnetic results delineate significant associated structures. Arsenic in soils and stream sediments has been the principal geochemical pathfinder historically and the new sampling and analyses for multiple trace elements provide improved coverage at a better detection limit. Cross-border soil geochemical anomalies also characterise the area around the vein deposits in South Armagh and County Monaghan, in Ordovician/Silurian rocks. The geochemistry survey has revealed more widely distributed gold anomalies in stream sediments in other areas and mapped significant anomalies in platinum group elements over the Antrim basalts. Here again, the airborne magnetic and electromagnetic imagery reveal new structural information, particularly in those areas obscured by glacial deposits and peat. Following this success, the airborne geophysics and geochemistry surveys have been extended over 12,300 km2 of the six border counties of the Republic of Ireland (Donegal, Sligo, Leitrim, Cavan, Monaghan and Louth) under the cross-border ‘Tellus Border’ project, financed by the INTERREG IVA programme of the European Regional Development Fund. This new survey work is jointly managed by the Geological Survey of Northern Ireland and the Geological Survey of Ireland. The integrated geophysical and geochemical results of Tellus and Tellus Border surveys are being released throughout 2013 and have prompted further interest in mineral prospectivity as well as environmental research into soils, surface and groundwater, radioactivity and ecology. The project has stimulated joint data collection with the private sector. In 2012 the airborne survey was extended in eastern Co. Mayo and north Co. Roscommon in collaboration with a mining company, which has made the data publicly available. Another company has already taken out four licences on the basis of Tellus Border geochemical results released in February 2013. These data reveal the continuation of a trend established on adjoining licenses held in Northern Ireland. New fire-assay gold analyses of the Tellus Border stream sediment samples will be released in 2013. Together the merged Tellus and Tellus Border geochemical and geophysical data are expected to promote further investment in this cross-border region

Evaluation of different cell disruption processes on encysted cells of Haematococcus pluvialis: effects on astaxanthin recovery and implications for bio-availability

Although Haematococcus pluvialis is one of the most importantnatural sources of the carotenoid astaxanthin as a pigmentor for theaquaculture industry, the thick sporopollenin cell wall in the cysts hindersastaxanthin extraction and its subsequent bio-availability to fish. A rangeof physical and chemical processes were tested to promote the disruptionof the encysted cells. The efficacy of these processes was evaluated interms of astaxanthin recovery, which was assessed by determining theextent of leaching of astaxanthin into an organic solvent. The processestested were: autoclave 30 min, 121 °C, 1 atm; HCl 0.1 M, 15min and 30 min; NaOH 0.1 M, 15 min and 30 min; enzymatictreatment with a mixture of 0.1% protease K and 0.5% driselase in aphosphate buffer, pH 5.8, 30 °C, for one hour; spray drying, inlet180 °C, outlet 115 °C; and mechanical disruption, with acell homogeniser developed for this purpose. The mechanical(homogenisation) and autoclave treatments were the most effective in termsof extraction and availability

Batch fabrication of micro-coils for MR spectroscopy on silicon

Published versio

Direct health costs of inflammatory polyarthritis 10 years after disease onset:Results from the Norfolk Arthritis Register

Objectives: To explore the change in direct medical costs associated with inflammatory polyarthritis (IP) 10 to 15 years after its onset. Methods: Patients from the Norfolk Arthritis Register who had previously participated in a health economic study in 1999 were traced 10 years later and invited to participate in a further prospective questionnaire-based study. The study was designed to identify direct medical costs and changes in health status over a 6-month period using previously validated questionnaires as the primary source of data. Results: A representative sample of 101 patients with IP from the 1999 cohort provided complete data over the 6-month period. The mean disease duration was 14 years (SD 2.1, median 13.6, interquartile range 12.6–15.4). The mean direct medical cost per patient over the 6-month period was £1496 for IP (inflated for 2013 prices). This compared with £582 (95% CI £355–£964) inflated to 2013 prices per patient with IP 10 years earlier in their disease. The increased cost was largely associated with the use of biologics in the rheumatoid arthritis subgroup of patients (51% of total costs incurred). Other direct cost components included primary care costs (11%), hospital outpatient (19%), day care (12%), and inpatient stay (4%). Conclusion: The direct healthcare costs associated with IP have more than doubled with increasing disease duration, largely as a result of the use of biologics. The results showed a shift in the direct health costs from inpatient to outpatient service use

The X-ray nebula around the Seyfert 2 galaxy NGC4388

We report on X-ray emission from the Seyfert 2 galaxy NGC4388 observed with the Chandra X-ray Observatory. A hard X-ray peak is found at the position of the active nucleus suggested by optical and radio observations. Extended soft X-ray emission correlates well with the ionization cone found in optical line emission. A large soft X-ray extension is found up to 16 kpc to the north of the galaxy. Photoionized gas with low ionization parameters (xi<3) appears to be the likely explanation of this emission. The same ionized gas clouds could be responsible for the optical [OIII] emission. Fe K line emission from cold material is found to be extended by a few kpc.Comment: 12 pages, one colour figure included, MNRAS in pres

Large variation in the Rubisco kinetics of diatoms reveals diversity among their carbon-concentrating mechanisms

While marine phytoplankton rival plants in their contribution to global primary productivity, our understanding of their photosynthesis remains rudimentary. In particular, the kinetic diversity of the CO₂-fixing enzyme, Rubisco, in phytoplankton remains unknown. Here we quantify the maximum rates of carboxylation (Kcatᶜ), oxygenation (Kcatᵒ), Michaelis constants (K m) for CO₂ (K C) and O₂ (K O), and specificity for CO₂ over O₂ (SC/O) for Form I Rubisco from 11 diatom species. Diatom Rubisco shows greater variation in KC (23-68 μM), SC/O (57-116mol mol⁻¹), and KO (413-2032 μM) relative to plant and algal Rubisco. The broad range of KC values mostly exceed those of C₄ plant Rubisco, suggesting that the strength of the carbon-concentrating mechanism (CCM) in diatoms is more diverse, and more effective than previously predicted. The measured k cat c for each diatom Rubisco showed less variation (2.1-3.7s⁻¹), thus averting the canonical trade-off typically observed between KC and kcatᶜ for plant Form I Rubisco. Uniquely, a negative relationship between KC and cellular Rubisco content was found, suggesting variation among diatom species in how they allocate their limited cellular resources between Rubisco synthesis and their CCM. The activation status of Rubisco in each diatom was low, indicating a requirement for Rubisco activase. This work highlights the need to better understand the correlative natural diversity between the Rubisco kinetics and CCM of diatoms and the underpinning mechanistic differences in catalytic chemistry among the Form I Rubisco superfamily

Determining Reheating Temperature at Colliders with Axino or Gravitino Dark Matter

After a period of inflationary expansion, the Universe reheated and reached full thermal equilibrium at the reheating temperature T_R. In this work we point out that, in the context of effective low-energy supersymmetric models, LHC measurements may allow one to determine T_R as a function of the mass of the dark matter particle assumed to be either an axino or a gravitino. An upper bound on their mass may also be derived.Comment: 19 pages, some improvements, JHEP versio

Divergence Cancellation and Loop Corrections in String Field Theory on a Plane Wave Background

We investigate the one-loop energy shift E to certain two-impurity string states in light-cone string field theory on a plane wave background. We find that there exist logarithmic divergences in the sums over intermediate mode numbers which cancel between the cubic Hamiltonian and quartic ``contact term''. Analyzing the impurity non-conserving channel we find that the non-perturbative, order g_2^2 sqrt(lambda') contribution to E/mu predicted in hep-th/0211220 is in fact an artifact of these logarithmic divergences and vanishes with them, leaving an order g_2^2 lambda' contribution. Exploiting the supersymmetry algebra, we present a form for the energy shift which appears to be manifestly convergent and free of non-perturbative terms. We use this form to argue that E/mu receives order g_2^2 lambda' contributions at every order in intermediate state impurities.Comment: 27 pages; added references, acknowledgments, missing normalization in equations 2.3 - 2.8, also cleaned up notation, and added a few footnote

Oral contraceptive use and anterior cruciate ligament injury: comparison of active comparator new user cohort and case-control study designs

Background: This study further investigates a protective association between oral contraceptive (OC) use and anterior cruciate ligament (ACL) injury noted in prior case-control studies. Methods: Active comparator new user cohort analysis of women aged 13–45 years in the United States from the IBM MarketScan Commercial Claims and Encounters database who newly-initiated low-dose OCs (exposed) or underwent intrauterine device (IUD) insertion (comparison group) from 2000 to 2014. Women were followed for ACL injury starting 90 days after OC initiation or IUD insertion until OC or IUD discontinuation or end of continuous enrollment. Adjusted hazard ratios (adjHR) and 95% confidence intervals (CI) were estimated controlling for age. Secondary analysis replicated previously-published case-control studies assessing “ever” versus “never” OC use over 1- and 5-year periods among women who underwent ACL reconstruction compared to age-matched controls. Results: In the cohort analysis, 2,370,286 women initiated OCs and 621,798 underwent IUD insertion. There were 3571 (0.15%) ACL injuries during an average 370.6 days of continuous OC use and 1620 (0.26%) during an average 590.5 days of IUD use. No difference in risk of ACL injury was observed between OC initiators and IUD users (adjHR = 0.95; 95%CI 0.89, 1.01). The case-control analysis replicated the slight protective association observed in prior studies over a 5-year period (OR = 0.90; 95%CI 0.85, 0.94). Conclusions: This cohort study suggests no association between OC use and ACL injury, while the case-control study suggested bias from uncontrolled confounding and selection factors may have influenced previous findings that suggested a protective association between OC use and ACL injury